NOTES:
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Paper 2 . 1 . 2 . 1 Tapped Delay Line Channel Models at 5.3 GHz in Indoor Environments
Paper 2 . 1 . 2 . 2 Spatial and Temporal Characteristics of 60 GHz Indoor Channels
Paper 2 . 1 . 2 . 3 Experimental Investigations of Correlation Properties of MIMO Radio Channels for Indoor Picocell Scenario
Paper 2 . 1 . 2 . 4 Indoor and Outdoor Measurements of Space, Polarization, and Angle Diversity for Cellular Base Station in Urban Environments
Paper 2 . 1 . 2 . 5 Simple and Accurate Path Loss Modeling at 5 GHz in Indoor Environments with Corridors
Paper 2 . 1 . 3 . 1 Impact of Human Shadowing on Temporal Variation of Broadband Indoor Radio Channel Characteristics and System Performance
Paper 2 . 1 . 3 . 2 Pedestrian-Induced Fading for Indoor Channels at 2.45, 5.7 and 62 GHz
Paper 2 . 1 . 3 . 3 Monte Carlo Simulation of Delay and Angle Spread in Different Building Environments
Paper 2 . 1 . 3 . 4 Detailed Radio Imaging of Buildings at 2.4 GHz
Paper 2 . 1 . 3 . 5 The Bluetooth Channel
Paper 2 . 1 . 4 . 1 Closed-loop Transmit Diversity Techniques for Multi-element Transceivers
Paper 2 . 1 . 4 . 2 Performance of Downlink Nulling in Combined Packet/Circuit Switched Systems
Paper 2 . 1 . 4 . 3 A Study of Polarization Diversity Using an Electromagnetic Spatio-Temporal Channel Model
Paper 2 . 1 . 4 . 4 Link-Optimal BLAST Processing with Multiple-Access Interference
Paper 2 . 1 . 4 . 5 Space-Time Coding for UMTS Performance Evaluation in Combination with Convolutional and Turbo Coding
Paper 2 . 2 . 2 . 1 Space Hopping Scheme Under Short Range Rician Multipath Fading Environment
Paper 2 . 2 . 2 . 2 Coherent Interference Suppression with an Adaptive Array Using Spatial Affine Projection Algorithm
Paper 2 . 2 . 2 . 3 Investigation of the Trade-off Characteristics of Beamforming Performance in DS-CDMA System
Paper 2 . 2 . 2 . 4 Downlink Capacity of Multirate DS-CDMA with Antenna Array and SIR Based Power Control in Multicell Environment
Paper 2 . 2 . 2 . 5 Non-stationary Interference Exciser in Smart Antenna Systems Using an Adaptive Gabor Expansion
Paper 2 . 2 . 3 . 1 An Adaptive Array Antenna for CDMA2000 System
Paper 2 . 2 . 3 . 2 Phase and Amplitude Calibration of a PCS Wideband Antenna Array
Paper 2 . 2 . 3 . 3 Capacity Enhancement Based on Using Adaptive Antenna Arrays Optimized for Trunking Efficiency
Paper 2 . 2 . 3 . 4 Optimum Element Arrangement of Adaptive Base Station Antennas for SDMA in Circular Cell
Paper 2 . 2 . 3 . 5 Adaptive Antennas in WCDMA Systems; Link Level Simulation Results
Paper 2 . 2 . 4 . 1 Match Filter Bound Analysis Used to Evaluate Range Increase Provided by an Adaptive Antenna Array
Paper 2 . 2 . 4 . 2 FDD DS-CDMA Downlink Beamforming by Modifying Oplink Beamforming Weights
Paper 2 . 2 . 4 . 3 Hybrid Adaptive Algorithm Based on Temporal Update and Spatial Spectrum Estimation for Adaptive Array Antenna
Paper 2 . 2 . 4 . 4 Soft Handoffs in Code Division Multiple Access Systems with Smart Antenna Arrays
Paper 2 . 2 . 4 . 5 Semi-blind Method for Adaptive Transmit Antenna Array for CDMA Systems
Paper 2 . 3 . 2 . 1 Joint Design of Adaptive Channel Coding and Multiple Access Control for Integrated Voice and Data Services in a Cellular Wireless Network|with Contention Queue
Paper 2 . 3 . 2 . 2 A Novel Multiuser Transmission Scheme Requiring No Channel Estimation and No Equalization at the Mobile Stations for the Downlink of TD-CDMA Operations in the TDD Mode
Paper 2 . 3 . 2 . 3 Multichannel CSMA with Signal Power-Based Channel Selection for Multihop Wireless Networks
Paper 2 . 3 . 2 . 4 A MAC Algorithm for Energy-limited Ad-hoc Networks
Paper 2 . 3 . 2 . 5 Extending Earliest-Due-Date Scheduling Algorithms for Wireless Networks with Location-Dependent Errors
Paper 2 . 3 . 3 . 1 A Queuing Priority Channel Access Protocol for Voice/Data Integration on the Air Interface of Microcellular Mobile Radio Networks
Paper 2 . 3 . 3 . 2 Demand Assignment Multiple Access Protocols for Wireless ATM Networks
Paper 2 . 3 . 3 . 3 Wavelet Packet Function Based RAKE /Adaptive Multichannel DFE Equalization for WPMA System over Frequency Selective Rayleigh Fading Channels
Paper 2 . 3 . 3 . 4 QoS Guarantees for Third Generation (3G) CDMA Systems via Admission and Flow Control
Paper 2 . 3 . 3 . 5 An OFDM Based Multicarrier MFSK System
Paper 2 . 3 . 4 . 1 An Iterative Approach to the Power Control Problem in Wireless Networks for Integrated Services
Paper 2 . 3 . 4 . 2 Spatial Multi-user Access OFDM with Antenna Diversity and Power Allocation
Paper 2 . 3 . 4 . 3 A Fast Cell Search Algorithm Using Code Block CPM in Asynchronous W-CDMA System
Paper 2 . 3 . 4 . 4 Weighted Fair Queueing for Data Service in a Multimedia CDMA System
Paper 2 . 3 . 4 . 5 Peak-to-Average Ratio Suppression Schemes in DFT Based OFDM
Paper 2 . 4 . 2 . 1 Optimal Turbo Decoding Metric Generation in a Pilot Assisted Coherent Wireless Communication System
Paper 2 . 4 . 2 . 2 Pilot-aided Adaptive Chip Equalizer Receiver for Interference Suppression in DS-CDMA Forward Link
Paper 2 . 4 . 2 . 3 Effects of Adaptive Equalization on the Performance of Broadband Wireless Communications in Fading Channels
Paper 2 . 4 . 2 . 4 Nonlinear Adaptive Blind Interference Cancellation for CDMA Systems
Paper 2 . 4 . 2 . 5 Implementation of an Experimental 384 kb/s Radio Link For High-Speed Internet Access
Paper 2 . 4 . 3 . 1 A Decoding Algorithm for I-Q Space-Time Coded Systems in Fading Environments
Paper 2 . 4 . 3 . 2 Efficient Evaluation of Error Probabilities for Systems with Intersymbol Interference an Gaussian Noise
Paper 2 . 4 . 3 . 3 Low-Complexity Channel Estimation for WCDMA Random Access
Paper 2 . 4 . 3 . 4 Proposal of OFDM System with Data Repetition
Paper 2 . 4 . 3 . 5 Stationary Schemes for Optimal Transmission over Fading Channels with Delay Constraint
Paper 2 . 4 . 4 . 1 A Blind Diversity Reception Based on Eigenfilter Approach for Mobile Communications
Paper 2 . 4 . 4 . 2 C/I Balancing under Limited Power Dynamics for JD-CDMA
Paper 2 . 4 . 4 . 3 WCDMA Initial Cell Search
Paper 2 . 4 . 4 . 4 Adaptive QAM Modulations with Complex Spreading for High-speed Mobile Multimedia Communications
Paper 2 . 4 . 4 . 5 Selection or the Most Efficient Shortened Reed Solomon Codes from a Neural Network Database
Paper 2 . 5 . 2 . 1 Joint Maximum Likelihood Approach in Overloaded Array Processing
Paper 2 . 5 . 2 . 2 Reduced Complexity of Multi-Code DS-CDMA Receiver Using a COF Only for a Pilot Channel
Paper 2 . 5 . 2 . 3 Signal Space Whitening MLSE with Multibeam Adaptive Array
Paper 2 . 5 . 2 . 4 Turbo MAP Decoder Design for IS-2000 System
Paper 2 . 5 . 2 . 5 Joint Decoding and Channel Estimation for Space-Time Codes
Paper 2 . 5 . 3 . 1 Antenna Diversity Combining Schemes for W-CDMA in Fading Multipath Channels
Paper 2 . 5 . 3 . 2 Interference Cancellation Using the Gibbs Sampler
Paper 2 . 5 . 3 . 3 Accurate Noise Estimates in Multicarrier Systems
Paper 2 . 5 . 3 . 4 An Improved Decision Feedback Receiver for CDMA IS-95 Reverse Link
Paper 2 . 5 . 3 . 5 On the Effect of Correlation in Multislot Link Layer Analysis for GPRS
Paper 2 . 5 . 4 . 1 A Block Coded Modulation Method for Variable-rate Data Transmission
Paper 2 . 5 . 4 . 2 Modeling Interference Diversity in GSM Networks
Paper 2 . 5 . 4 . 3 Adaptive Acquisition for DS-SS Systems with Antenna Diversity
Paper 2 . 5 . 4 . 4 Space-Time Bit-Interleaved Coded Modulation with an Iterative Decoding Strategy
Paper 2 . 5 . 4 . 5 UEP of Progressive Images in Wireless Channels
Paper 2 . 6 . 2 . 1 Power Control in a Multicell CDMA Data System Using Pricing
Paper 2 . 6 . 2 . 2 Performance of Link Adaptation in GPRS Network Simulations
Paper 2 . 6 . 2 . 3 Performance of Coded Higher Order Modulation Schemes and Hybrid ARQ for Next Generation Cellular Systems
Paper 2 . 6 . 2 . 4 Equalization and Multi-user Detection in Frequency Selective Channels for Space Time Block Coding Based Transmit Diversity (STTD)
Paper 2 . 6 . 2 . 5 Cutoff Rate Analysis of Pilot Assisted CDMA System with Power Control
Paper 2 . 6 . 3 . 1 Effects of Mobile Speed on System Performance, Results from Orange/Fujitsu UMTS Field Trials in UK
Paper 2 . 6 . 3 . 2 Transmission Delay Control for Single Frequency OFDM Multi-Base Stations in a Cell Using Position Information
Paper 2 . 6 . 3 . 3 Measurement Assessment for Link Quality Estimation in 3G Wireless Communication Networks
Paper 2 . 6 . 3 . 4 Data Fusion Based on Neural Network for the Mobile Subscriber Location
Paper 2 . 6 . 3 . 5 New Generation Features for Tactical Wireless Communication Networks
Paper 2 . 6 . 4 . 1 An Equal-Strength/Power-Suspended Power Control Scheme for a Cellular DS/CDMA System
Paper 2 . 6 . 4 . 2 Outage Performance Considerations in Cellular Systems: A Comparative Review
Paper 2 . 6 . 4 . 3 Quality of Service Management for Mixed Services in WCDMA
Paper 2 . 6 . 4 . 4 Joint Power Control, Base Station Assignment and Sectorization for CDMA Cellular Systems
Paper 2 . 6 . 4 . 5 Design of Cyclically Permutable Codes for PN Code Acquisition in WCDMA TDD Mode
Paper 2 . 7 . 2 . 1 Effect of Phase Noise on RF Communication Signals
Paper 2 . 7 . 2 . 2 Forward Link Capacity Based on Interference Characteristics in CDMA Systems
Paper 2 . 7 . 2 . 3 Traffic Modeling and Performance Analysis for Dual-Band Systems
Paper 2 . 7 . 2 . 4 Performance of Optimum Transmitter Power Control in WCDMA Cellular Mobile Systems
Paper 2 . 7 . 2 . 5 Mobile Location Method for Non-Line-of-Sight Situation
Paper 2 . 7 . 3 . 1 A New Hybrid MAP/MLSE Soft-output Adaptive Equalizer for TDMA-based Land Mobile Cellular Links
Paper 2 . 7 . 3 . 2 On the Achievable Network Capacity of the CDMA2000-1X System With and Without Transmit Diversity
Paper 2 . 7 . 3 . 3 CDMA Capacity on Pathloss and Power Control
Paper 2 . 7 . 3 . 4 Handoff Rerouting Scheme for Multimedia Connections in ATM-based Mobile Networks
Paper 2 . 7 . 3 . 5 Combinations of Power Controls for CDMA2000 Wireless Communications Systems
Paper 2 . 7 . 4 . 1 Power Control with Time Delay Compensation
Paper 2 . 7 . 4 . 2 Mobile Communications beyond Third Generation
Paper 2 . 7 . 4 . 3 Investigation of 3rd Generation Mobile Communication RACH Transmission
Paper 2 . 7 . 4 . 4 A Markov-Based Model for Performance Evaluation in Multimedia CDMA Wireless Transmission
Paper 2 . 7 . 4 . 5 Scheduling Strategies for Downlink Packet Transmission in W-CDMA UMTS
Paper 2 . 8 . 3 . 3 Some Results on Channel Capacity When Using Multiple Antennas
Paper 2 . 8 . 3 . 4 Comparison of Indoor Propagation Channel Characteristics at 893MHz and 37.2GHz
Paper 2 . 8 . 3 . 5 Wide Band Indoor Radio Channel Measurements at 5.8 GHz
Paper 2 . 8 . 3 . 6 Performance Evaluation of Space-Time Block Coding Using a Realistic Mobile Radio Channel Model
Paper 2 . 8 . 3 . 7 Combined Pilot Aided and Decision Directed Channel Estimation for the RAKE Receiver
Paper 2 . 8 . 3 . 9 Evaluation of Space-time Turbo-codes for Third Generation Systems
Paper 2 . 8 . 3 . 10 Spatial Domain Interference Canceler Using Multistage Adaptive Array with Precise Timing Estimation
Paper 2 . 8 . 3 . 15 Characterisation of Cross Polarisation Discrimination in Forest Environments
Paper 2 . 8 . 3 . 16 In-Network Evaluation of Mobile Handset Performance
Paper 2 . 8 . 3 . 17 The Fading Characteristics in the Microcellular Environments Using Deterministic Prediction Model
Paper 2 . 8 . 3 . 18 Statistical Characteristics of Pedestrian-Induced Fading
Paper 2 . 8 . 3 . 21 Prediction of Fading Signal in a Multipath Environment
Paper 2 . 8 . 3 . 24 An Antenna Array Receiver Using Channel Estimation In a DS/CDMA System with M-ary Orthogonal Modulation
Paper 2 . 8 . 3 . 26 Efficient Simulation of Fading Channels within a Packet Simulator
Paper 2 . 8 . 3 . 27 Subspace-Based Blind Joint Detection of Fading, Asynchronous Cochannel TDMA Signals
Paper 2 . 8 . 3 . 28 Multiple-Input Multiple-Output (MIMO) Radio Channel Measurements
Paper 2 . 8 . 3 . 30
Comparison of the Electromagnetic Properties of Building Materials at 5.8 GHz and 62.4
GHz
Paper 3 . 1 . 1 . 1
PCS Band Angle of Arrival Measurements Using a 4 Element Linear Array
Paper 3 . 1 . 1 . 2
Isolation and Analysis of the Log-Normal Shadowing Component
Paper 3 . 1 . 1 . 3
Finite Sample Estimates for Mobile Channels
Paper 3 . 1 . 1 . 4
Direction Dispersion and Space Selectivity in the Mobile Radio Channel
Paper 3 . 1 . 1 . 5
Radio Network Planning with Neural Networks
Paper 3 . 1 . 2 . 1
Water Enhancement for Macro amd Microcells
Paper 3 . 1 . 2 . 2
Joint Estimation of the Space-time Distributed Signal Parameters
Paper 3 . 1 . 2 . 3
Spatio-Temporal Characteristics at Base Station with Microwave Urban Propagation
Paper 3 . 1 . 2 . 4
A Multiple Input/Multiple Output Channel Model for Simulation of TX and RX Diversity
Wireless Systems
Paper 3 . 1 . 2 . 5
A Path Loss Model with Height Variation in Residential Areas Based on Experimental and
Theoretical Studies Using a 5G/2G Dual Band Antenna
Paper 3 . 1 . 3 . 1
Wideband Channel Sounding at 5.1 GHz for Angular and Polarisation Diversity on Hiperlan
Diversity
Paper 3 . 1 . 3 . 2
Radiation Phantoms for Handheld Phones
Paper 3 . 1 . 3 . 3
Mobile Radio Prediction Model Considering Long Term Fading in Urban Microcellular
Environment
Paper 3 . 1 . 3 . 4
An Analysis of Fading Mechanisms for Fixed Antennas
Paper 3 . 1 . 3 . 5
The Eta-mu Distribution: A General Fading Distribution
Paper 3 . 1 . 4 . 1
Application of RBF Neural Networks to the Prediction of Propagation Loss over Irregular
Terrain
Paper 3 . 1 . 4 . 2
Radio Propagation in Urban Small Cells Environment at 2 GHz: Experimental
Spatio-temporal Characterization and Spatial Wideband Channel Model
Paper 3 . 1 . 4 . 3
A Stochastic Multiple-Input-Multiple-Output Radio Channel Model for Evaluation of
Space-Time Coding Algorithms
Paper 3 . 1 . 4 . 4
Prediction of Path Loss in Environments with High Rised Buildings
Paper 3 . 1 . 4 . 5
Mathematical Models for Radiosignals Dynamic Range Prediction
Paper 3 . 2 . 1 . 1
Dynamic QoS Control for Wireless ATM Networks
Paper 3 . 2 . 1 . 2
QoS Constrained Resource Allocation for Multimedia Wireless Networks
Paper 3 . 2 . 1 . 3
Mobility Management and Routing Algorithms for Soft Handoff in Wireless Mobile Data
Network Using MGCP
Paper 3 . 2 . 1 . 4
A Framework for Mathematical Modeling of 2-tier Hierarchical Mobile Ad-Hoc Networks
Paper 3 . 2 . 1 . 5
Performance Evaluation of Hybrid OFDM/CDMA/SFH Approach for Wireless Multimedia
Paper 3 . 2 . 2 . 1
Soft Reservation Multiple Access with Priority Assignment(SRMA/PA): A Novel MAC
Protocol for QoS-Guaranteed Integrated Services in Mobile Ad-Hoc Networks
Paper 3 . 2 . 2 . 2
HOLPRO: A New Rate Scheduling Algorithm for CDMA Downlink Networks
Paper 3 . 2 . 2 . 3
Link Layer Buffer Size Distributions for FTP and HTTP/1.0 Applications in an IS-2000
System
Paper 3 . 2 . 2 . 4
Mobile IP Based DECT Multimedia Architecture for IMT-2000
Paper 3 . 2 . 2 . 5
Multimedia Mobile Terminal P-link Station with TDMA-TDD Technology
Paper 3 . 2 . 3 . 1
An Enhanced Reliable Multicast Protocol for Wireless Environments
Paper 3 . 2 . 3 . 2
Application of Erasure-only Decoded Reed-Solomon Codes in Cell Recovery for Congested
ATM Networks
Paper 3 . 2 . 3 . 3
On-Demand Associativity-Based Multicast Routing for Ad Hoc Mobile Networks
Paper 3 . 2 . 3 . 4
Optimum Rate and Power Adaptation for Multirate CDMA
Paper 3 . 2 . 3 . 5
Quality of Service Control over GPRS Data Network
Paper 3 . 2 . 4 . 1
IEEE 802.11 and ETSI Hiperlan Type 1: Performance Comparison under Influence of a
Burst-Noise Channel
Paper 3 . 2 . 4 . 2
TCP over Asymmetric CDMA Radio Links
Paper 3 . 2 . 4 . 3
Block Codes with Soft-decision Trellis Decoding in Compressed Image Transmission over
Rayleigh Fading Channel
Paper 3 . 2 . 4 . 4
Evaluation of Mobile Ad Hoc Networking Techniques in a Cellular Network
Paper 3 . 2 . 4 . 5
Erlang Capacity of CDMA Systems with Adaptive Arrays
Paper 3 . 3 . 1 . 1
Performance of TCP/IP over IS-2000 Based CDMA Radio Links
Paper 3 . 3 . 1 . 2
Performance of Multicarrier CDMA with MSK Modulation and One-bit Differential Detection
in a Multipath Fading Channel
Paper 3 . 3 . 1 . 3
Performance of Space-Time Multi-user Detection in Synchronous DS-CDMA Systems with FEC
Coding
Paper 3 . 3 . 1 . 4
Intelligent Call Admission Control for Differentiated QoS Provisionings in Wideband
CDMA Cellular Systems
Paper 3 . 3 . 1 . 5
Dynamic 3G Network Selection for Increasing the Competition in the Mobile
Communications Market
Paper 3 . 3 . 2 . 1
Efficient Water-filling Algorithms for Gaussian Multiaccess Channel with ISI
Paper 3 . 3 . 2 . 2
Dynamic Time-Division-Duplex Wireless Local Loop
Paper 3 . 3 . 2 . 3
Admission Control for Future Multi-Service Wideband Direct-Sequence CDMA (WCDMA) System
Paper 3 . 3 . 2 . 4
Analysis of the Uplink of an Asynchronous Multi-user DMT OFDMA System
Paper 3 . 3 . 2 . 5
Radio Link Performance and Traffic Capacity of Indoor Wireless Systems Integrated with
Outdoor Cellular
Paper 3 . 3 . 3 . 1
Admission Control in Wireless Systems with Heterogeneous Traffic and Overlay Cell
Structure
Paper 3 . 3 . 3 . 2
An Improved Channel Inversion Based Adaptive OFDM System in the Presence of Channel
Errors and Rapid Time Variations
Paper 3 . 3 . 3 . 3
Integrated Air Interface Access Schemes for Broadband Wireless Communications
Paper 3 . 3 . 3 . 4
A Modified Hopfield Neural Network Algorithm for Cellular Radio Channel Assignment
Paper 3 . 3 . 3 . 5
A Novel FHSS Multiple-Access System Using M-ary Orthogonal Walsh Modulation
Paper 3 . 3 . 4 . 1
Quality of Service and Grade of Service Optimisation with Distributed Dynamic Channel
Allocation Schemes Based on Hopfield Neural Network Algorithms
Paper 3 . 3 . 4 . 2
High-rate OFDM Codes for Peak Envelope Power Reduction and Error Correction
Paper 3 . 3 . 4 . 3
Trunking Efficiency and Load Balance for Multiple-Carrier CDMA Systems
Paper 3 . 3 . 4 . 4
Spatial CDMA - A Distributed Multiple Antenna Access Method for Broadband Wireless
Communication
Paper 3 . 3 . 4 . 5
Theoretical Analysis of the Pilot Tones Assisted COFDM System over Fast Multipath
Fading Channels
Paper 3 . 4 . 1 . 1
Pre-equalization of MIMO Wireless Channels with Delay Spread
Paper 3 . 4 . 1 . 2
Combining Turbo-Code and Co-channel Interference Cancellation
Paper 3 . 4 . 1 . 3
Adaptive Successive Interference Cancellation for the IS-95 Uplink
Paper 3 . 4 . 1 . 4
Initial Characterisation of Multiple-Input Multiple-Output (MIMO) Channels for
Space-Time Communication
Paper 3 . 4 . 1 . 5
Application of RS-coded MPSK Modulation Scenarios to Compressed Image Communication in
Mobile Fading Channel
Paper 3 . 4 . 2 . 1
Parallel Decoding of Turbo Codes Using Soft Output T-Algorithms.
Paper 3 . 4 . 2 . 2
Amplitude and Phase Estimation Considerations for Asynchronous CDMA with
Superorthogonal Codes and Successive Interference Cancellation
Paper 3 . 4 . 2 . 3
RAKE Receiver with Adaptive Interference Cancellers for a DS-CDMA System in Multipath
Fading
Paper 3 . 4 . 2 . 4
Joint Equalization and Decoding of Trellis Coded Signals Using the Generalized Viterbi
Algorithm
Paper 3 . 4 . 2 . 5
Performance of HD-Parallel Interference Cancellation in DS-CDMA System
Paper 3 . 4 . 3 . 1
Reducing the Error Floor in Turbo Codes by Using Non-Binary Constituent Encoders
Paper 3 . 4 . 3 . 2
A New Efficient Decision-Aided ISI Canceler for Mobile Communication Systems
Paper 3 . 4 . 3 . 3
New TCM Codes for AWGN and ISI Channel by Matched Symbol-Mapping Method
Paper 3 . 4 . 3 . 4
Interference Suppression Receiver with Adaptive Antenna Array for Code Division
Multiple Access Communication Systems
Paper 3 . 4 . 3 . 5
A New Space-time Minimum Variance Receiver for CDMA Systems and its Performance
Analysis
Paper 3 . 4 . 4 . 1
Combined DA/DD/NDA Channel Estimation Techniques for Downlink WCDMA
Paper 3 . 4 . 4 . 2
Evaluation of the MAP Decoding for the Turbo Codes of IMT-2000
Paper 3 . 4 . 4 . 3
A Spreading Sequence Allocation Procedure for MC-CDMA Transmission Systems
Paper 3 . 4 . 4 . 4
Improved Viterbi Decoder Metrics for Two-Stage Detectors in DS-CDMA
Paper 3 . 4 . 4 . 5
Iterative Super-Exponential-Estimator for Fast Blind Channel Identification of Mobile
Radio Fading Channels
Paper 3 . 5 . 1 . 1
Performance of TCM Schemes over Equalized Channels
Paper 3 . 5 . 1 . 2
Optimal Adaptive Precoding for Frequency-Selective Nagakami-m Fading Channels
Paper 3 . 5 . 1 . 3
Blind Adaptive Multiuser Detection for Multirate CDMA
Paper 3 . 5 . 1 . 4
Soft-Output M-Algorithm for the Concatenation of Detecting and Decoding
Paper 3 . 5 . 1 . 5
Demodulation of D2PSK with a DPSK Detector and Improved Error Performance in AWGN
Paper 3 . 5 . 2 . 1
A Method to Improve the Transmission Performance under Slow to Fast Fading Environment
Paper 3 . 5 . 2 . 2
Performance Evaluation of a Direct Conversion Radio for Tri-Band GSM and GPRS
Paper 3 . 5 . 2 . 3
Evaluation of Link-level Performance Improvements by Using Smart Antennas for the
TD-CDMA Based UTRA TDD Mobile Radio System
Paper 3 . 5 . 2 . 4
A Fast Selective-Direction MMSE Timing Recovery Algorithm
Paper 3 . 5 . 2 . 5
Iterative Channel Estimation and Decoding with Product Codes in Multicarrier Systems
Paper 3 . 5 . 3 . 1
Coding of PPM Based Modulation Techniques to Improve the Performance of Infrared WLAN's
Paper 3 . 5 . 3 . 2
Optimal Sequences to Suppress the Multiuser Interference for CDMA Systems
Paper 3 . 5 . 3 . 3
Turbo Decoding in a Rayleigh Fading Channel with Estimated Channel-State Information
Paper 3 . 5 . 3 . 4
A Searcher for the Synchronization Channel of WCDMA
Paper 3 . 5 . 3 . 5
Reduced-Complexity MAP Equalizer for Dispersive Channels
Paper 3 . 5 . 4 . 1
Mobile Radio Multi-Link Analysis
Paper 3 . 5 . 4 . 2
An Effective CIC (Co-channel Interference Canceller) Scheme for Multi-rate CDMA
Paper 3 . 5 . 4 . 3
A Novel Coherent Demodulation for M-QAM OFDM Signal Operating in the Burst Mode
Paper 3 . 5 . 4 . 4
A Novel Symbol Frame and Carrier Frequency Synchronization for Burst Mode OFDM Signal
Paper 3 . 5 . 4 . 5
Performance of an Experimental 384 kb/s 1900 MHz OFDM Radio Link in a Wide-Area
High-Mobility Environment
Paper 3 . 6 . 1 . 1
Transmission of Embedded VBR Multimode Encoded Speech on UMTS Common Packet Channels
Paper 3 . 6 . 1 . 2
A Connection Admission Control Using Transient Outage Probability in CDMA Systems
Paper 3 . 6 . 1 . 3
Classification and Characterisation of Mobile Broadband Services
Paper 3 . 6 . 1 . 4
A Cost Effective Paging Scheme for IMT-2000 Systems
Paper 3 . 6 . 2 . 1
Hardware-Fitted Modeling and Simulation of QoS of VoIP Over a Wireless LAN
Paper 3 . 6 . 2 . 2
Uplink Capacity of Multirate Multicell CDMA Wireless Local Loop System with Narrowbeam
Antenna and SIR Based Power Control
Paper 3 . 6 . 2 . 3
Diversity Combining of a Fast Varying, Correlated Multipath Fading Channel for
Direct-Sequence Spread-Spectrum Systems
Paper 3 . 6 . 2 . 4
A Cellular Architecture for Supporting Geocast Services
Paper 3 . 6 . 2 . 5
Design and Implementation of an Experimental Wireless Terminal
Paper 3 . 6 . 3 . 1
Soft Handover Gain in WCDMA
Paper 3 . 6 . 3 . 2
Voice/Data Transmissions in Common Packet Channel of 3GPP
Paper 3 . 6 . 3 . 3
Performance Analysis of Group Handoff in Fiber-Optic Cellular System
Paper 3 . 6 . 3 . 4
On the Rake Receiver Performance
Paper 3 . 6 . 3 . 5
Dealing with Location Uncertainty in Mobile Networks Using Contextual Temporal Fuzzy
Cognitive Maps
Paper 3 . 6 . 4 . 1
The Rough Road to IMT-2000 RTT Standard
Paper 3 . 6 . 4 . 2
Link Performance Evaluation of EGPRS in LA and IR Modes
Paper 3 . 6 . 4 . 3
Performance Evaluation of Cellular Mobile Systems with Successive Co-Channel
Interference Cancellation
Paper 3 . 6 . 4 . 4
A New Type of Multiuser Detector for CDMA Mobile Communication
Paper 3 . 6 . 4 . 5
Adjustment Loop Transmit Power Control During Soft Handover in CDMA Cellular Systems
Paper 3 . 7 . 1 . 1
Optimizing Antenna Parameters for Sectorized W-CDMA Networks
Paper 3 . 7 . 1 . 2
An Exclusive Intergroup Handoff Algorithm in Fiber-Optic Microcell/Picocell Radio
System
Paper 3 . 7 . 1 . 3
Enhanced Soft Handover Algorithms for UMTS System
Paper 3 . 7 . 1 . 4
Automatic Base Station Placement And Dimensioning for Mobile Network Planning
Paper 3 . 7 . 1 . 5
Impact of Mobile-Originated Short Message Service on the Digital Control Channel of
TDMA Systems
Paper 3 . 7 . 2 . 1
Sigmoid-Basis Nonlinear Power Control Algorithm for Mobile Radio Systems
Paper 3 . 7 . 2 . 2
Modification of Maximum Power Handoff with Timer (MPHT) Algorithm in Cellular Mobile
Communications
Paper 3 . 7 . 2 . 3
New Handoff Initiation Algorithm
(Optimum Combination of Hysteresis & Threshold Based Methods)
Paper 3 . 7 . 2 . 4
Iterative Equalization and Decoding with Channel Shortening Filters for Space-Time
Paper 3 . 7 . 2 . 5
Mobile Stations Location with Heterogeneous Data
Paper 3 . 7 . 3 . 1
Simulation Results of a Typical GSM Pico-cell System
Paper 3 . 7 . 3 . 2
Novel Strategy for Call Admission Control
Paper 3 . 7 . 3 . 3
Performance Analysis of GSM Traffic Channel Capacity With(out) High Speed Circuit
Switched Data
Paper 3 . 7 . 3 . 4
Performance Evaluation of an AAL2 Link Transmission Scheme for Voice and Data Packets
in BS-BSC Links
Paper 3 . 7 . 3 . 5
Suppress Multi-Access Interference Detector Based on Software Radio
Paper 3 . 7 . 4 . 1
Capacity Simulations and Analysis of CDMA2000 Packet Data Services
Paper 3 . 7 . 4 . 2
Effects of Code Acquisition Design Parameters in the IMT-2000 System
Paper 3 . 7 . 4 . 3
Optimization of Fixed Network Design in Cellular Systems Using Local Search Algorithms
Paper 3 . 7 . 4 . 4
A Formal Approach to Modeling and Performance Analysis of Shared Channels
Paper 3 . 7 . 4 . 5
A New Method to Solve the Dropped Call in CDMA Cellular System
Paper 3 . 8 . 1 . 1
Up-link Performance of the DQRUMA MAC Protocol in a Realistic Indoor Environment for
W-ATM Networks.
Paper 3 . 8 . 1 . 12
Mutual Coupling and Scattering Effects on Cellular CDMA Systems Using Smart Antennas
Paper 3 . 8 . 1 . 15
Field Test Results for Beam and Null Simultaneous Steering S/T-Equalizer in Broadband
Mobile Communication Environment
Paper 3 . 8 . 1 . 17
Validation of Handset Antenna Test Methods
Paper 3 . 8 . 1 . 18
Sensitivity Analysis of Compact Antenna Arrays in Correlated Nakagami Fading Channels
Paper 3 . 8 . 1 . 19
Measurements of Wideband Multi-element Transmit - Receive Diversity Channels in the
UMTS-band
Paper 3 . 8 . 1 . 20
A Pre-FFT Equalizer Design for Application to HIPERLAN/2
Paper 3 . 8 . 1 . 22
Spreading Sequence Sets with Zero Correlation Zone for Quasi-Synchronous CDMA
Communication Systems
Paper 3 . 8 . 1 . 23
Tracking of Time-Frequency Misalignments in 2D-Pilot-Symbol-Aided Coherent OFDM Systems
Paper 3 . 8 . 1 . 24
On Optimum Stochastic Rate/Power Control: Solution by a Primal-Dual Algorithm
Paper 3 . 8 . 3 . 1
Channel Assignment in Cellular Networks without Channel Separation Constraints
Paper 3 . 8 . 3 . 2
The System Performance Analysis of Link Adaptation in Hiperlan/2
Paper 3 . 8 . 3 . 3
CLR Performance of VBR Traffic in Wireless ATM Access Networks
Paper 3 . 8 . 3 . 4
An Optimum Rate/Power Allocation Scheme for Downlink in Hybrid CDMA/TDMA Cellular
System
Paper 3 . 8 . 3 . 5
Applying Splitting Algorithms to Channel Allocation Problems-Parameter Selection
Paper 3 . 8 . 3 . 6
A Multiple Access/Self Interference Canceller Receiver for DS-CDMA Multiuser Detection
over Fading Channels
Paper 3 . 8 . 3 . 7
A Prioritized Random Access with Discriminative Power Ramping Step Size
Paper 3 . 8 . 3 . 8
An Adaptive Two-Stage Decorrelator for DS/CDMA Systems
Paper 3 . 8 . 3 . 9
Hierarchical Cell Structures with Adaptive Radio Resource Management
Paper 3 . 8 . 3 . 10
Capacity Comparison of Packet Options in CDMA2000 with Various Power Control Methods
Paper 3 . 8 . 3 . 12
Exploring Adaptive Turbo Coded Modulation for Flat Fading Channels
Paper 3 . 8 . 3 . 13
Dedicated Priority Function SEG for TD-CDMA Cellular System
Paper 3 . 8 . 3 . 15
Mobile Assisted Handoff Based on Euclidean Distance Metric
Paper 3 . 8 . 3 . 17
An OFDM System with Reduced Non-linear Effect
Paper 3 . 8 . 3 . 18
Throughput Enhancement in TDMA Through Carrier Interference Pulse Shaping
Paper 3 . 8 . 3 . 19
Hybrid Type-II ARQ/AMS Supported by Channel Predictive Scheduling in a Multi-User
Scenario
Paper 3 . 8 . 3 . 20
Performance Analysis of Fixed Cell Assignment in Broadband Wireless Networks
Paper 3 . 8 . 3 . 21
An Investigation on Capacity Versus Guard-Bands for the TDD Mode in UMTS
Paper 3 . 8 . 3 . 22
Fair Resource Management in Diverse Cellular Systems
Paper 3 . 8 . 3 . 23
A New Estimation Scheme for Frequency and Timing Offsets in OFDM Systems
Paper 3 . 8 . 3 . 26
Improving the Transmission Efficiency in the Mobile Communication Systems Using Turbo
Codes
Paper 3 . 8 . 3 . 27
Comparison of Fading Channel Capacity Under Different CSI Assumptions
Paper 3 . 8 . 3 . 28
Comparison of the Level Crossing Rate and Average Fade Duration of Rayleigh, Rice, and
Nakagami Fading Models with Mobile Channel Data
Paper 3 . 8 . 3 . 29
Considering Downlink Intermodulation Distortion in Switched Multibeam Antennas for
Cellular Radio Systems
Paper 3 . 8 . 3 . 30
Simulation of Error Process on Mobile Radio Channels Based on Chaos Equations
Paper 4 . 1 . 1 . 1
Building Shielding Loss Measurements and Modelling at the 5 GHz Band in Office Building
Areas
Paper 4 . 1 . 1 . 2
Engineering Aspects and Performance Evaluation of a Multi-Service Low Earth Orbit
Mobile Satellite Communication System
Paper 4 . 1 . 1 . 3
Improving Subscriber Position Location Using a Hybrid Satellite-assisted and
Network-based Technique
Paper 4 . 1 . 1 . 4
Error Control for Ka-Band Land Mobile Satellite Communications Systems
Paper 4 . 1 . 1 . 5
Wideband Wave Propagation Measurements for Local Multipoint Distribution Systems (LMDS)
at 26 GHz
Paper 4 . 1 . 2 . 1
Role of PAF in a Multi-satellite CDMA Based LEO Satellite System
Paper 4 . 1 . 2 . 2
Location-aware Long-lived Route Selection in Wireless Ad Hoc Networks
Paper 4 . 1 . 2 . 3
Bayesian Bootstrap Filtering for Multiple Mobile Position Determination Using LEO
Satellites
Paper 4 . 1 . 2 . 4
Adaptive Dynamic Channel Allocation Scheme for Spotbeam Handover in LEO Satellite
Networks
Paper 4 . 1 . 2 . 5
Performance Evaluation of Intersegment Handover Procedures in UMTS Scenario
Paper 4 . 1 . 3 . 1
Bluetooth-based Wireless Connectivity in an Automotive Environment
Paper 4 . 1 . 3 . 2
A New Approach to the Geometry of TOA Location
Paper 4 . 1 . 3 . 3
Wireless Communication System Architecture and Physical Layer Design for Airport
Surface Management
Paper 4 . 1 . 3 . 4
Enhancing Authentication Mechanism with Mobile Agent in Mobile Communication System
Paper 4 . 1 . 3 . 5
Security Architecture for Wireless Residential Networks
Paper 4 . 1 . 4 . 1
On Performance of Switching Techniques for Integrated Services in CDMA Wireless Systems
Paper 4 . 1 . 4 . 2
A Power-Saving Multicast Routing Scheme in 2-tier Hierarchical Mobile Ad-Hoc Networks
Paper 4 . 1 . 4 . 3
An Expert System Architecture for the Design of Local Area Networks
Paper 4 . 1 . 4 . 4
Performance Analysis of Handoff Scheme in Integrated Voice/Data Wireless Networks
Paper 4 . 1 . 4 . 5
Delay Performance Analysis of Voice Traffic in a Cellular Wireless ATM Network
Paper 4 . 2 . 1 . 1
Interfacing to the On-Board Diagnostic System
Paper 4 . 2 . 1 . 2
Vehicular Information BROadcasting Relay (VIBROR) Protocol for Inter-Vehicle
Communications
Paper 4 . 2 . 1 . 3
Distributed Antenna System for Mass Transit Communications
Paper 4 . 2 . 1 . 4
An Anti-Car-Collision System Using GPS and 5.8GHz Inter-Vehicle Communication at an
Off-Sight Intersection
Paper 4 . 2 . 1 . 5
Technical Evaluation of an Electronic Millimeter Wave Pre-View Mirror
Paper 4 . 2 . 2 . 1
Real-Time Low Cost Passive Imaging System for Automotive Applications
Paper 4 . 2 . 2 . 2
Positioning Emergency Calls Along Roads and Motorways Using a GSM Dedicated Cellular
Radio Network
Paper 4 . 2 . 2 . 3
On-board Dynamics Failure Detection of the Two-motor-driven Electric Vehicle System
Paper 4 . 2 . 2 . 4
Hybrid OFDM for Future DSRC Applications
Paper 4 . 2 . 3 . 1
Evaluation of GPS Availability for Train Positioning Along a Railway Line
Paper 4 . 2 . 3 . 2
Comparison of Current Solutions for the Provision of Voice Services to Passengers on
High Speed Trains
Paper 4 . 2 . 3 . 3
Metro-North Railroad Telecommunications Infrastructure Project
Paper 4 . 2 . 3 . 4
Potential Use of Near, Mid and Far Infrared Laser Diodes in Automotive LIDAR
Applications.
Paper 4 . 2 . 3 . 5
Modeling of Hybrid Electric Vehicles Using Gyrator Theory: Application to Design
Paper 4 . 2 . 4 . 1
Modeling and Control of a Hybrid Electric Vehicle
Paper 4 . 2 . 4 . 2
The Multisensor Tracking System with the Airborne Sensor to Mitigate the Effect of
Cross-Range Errors
Paper 4 . 2 . 4 . 3
Mobile Location Estimation in Cellular Networks Using Fuzzy Logic
Paper 4 . 3 . 1 . 1
Capacity Enhancement Using Intelligent Relaying for Future Personal Communication
Systems
Paper 4 . 3 . 1 . 2
Adaptive Transmission Rate Control Scheme for ABR Services in the CBR and ABR Services
Integrated DS/CDMA Systems
Paper 4 . 3 . 1 . 3
Telegeoinformatics for Efficient Resource Allocation and Protocol Development in
Wireless Networks
Paper 4 . 3 . 1 . 4
Packet Scheduling in SDMA Based Wireless Networks
Paper 4 . 3 . 1 . 5
Uplink Acquisition of Synchronisation Parameters in MC-CDMA Systems
Paper 4 . 3 . 2 . 1
DRMA with Multiple Slots Reservation and Retransmission Algorithm Using Exponential
Backoff Scheme
Paper 4 . 3 . 2 . 2
Capture with Delay and Power Randomization in Spread-Spectrum CDMA Slotted ALOHA
System
Paper 4 . 3 . 2 . 3
Maximum Packing Channel Assignment Algorithm in Multi-Rate Traffic Microcellular
Networks
Paper 4 . 3 . 2 . 4
Predictive Adaptive Loading for Hiperlan II
Paper 4 . 3 . 2 . 5
A Radio Channel Emulator for WCDMA, Based on the Hidden Markov Model (HMM)
Paper 4 . 3 . 3 . 1
The Impact of Front End LNA on Cellular System
Paper 4 . 3 . 3 . 2
Performance Comparison of the Radio Link Protocols of IEEE802.11a and HIPERLAN/2
Paper 4 . 3 . 3 . 3
Adaptive Traffic Control Scheme in Hierarchically Structured CDMA Cellular Systems
Paper 4 . 3 . 3 . 4
Interference-Plus-Noise Covariance Matrix Estimation for Adaptive Space-time Processing
of DS/CDMA Signals
Paper 4 . 3 . 3 . 5
An Iterative Heuristic Algorithm for Applied Channel Assignment
Paper 4 . 3 . 4 . 1
Forward Link Capacity of Coherent DS-CDMA and MC-CDMA Broadband Packet Wireless Access
in a Multi-cell Environment
Paper 4 . 3 . 4 . 2
A Power Control and Scheduling Concept for EGPRS
Paper 4 . 3 . 4 . 3
Cellular Coverage for Efficient Transmission Performance in MBS
Paper 4 . 3 . 4 . 4
Sensitivity of Performance of SARP and HARP to Traffic Loading Variations in a
Hierarchical Cellular System under Non-uniform Traffic Distribution
Paper 4 . 3 . 4 . 5
Uplink and Downlink Capacity Evaluations of a Multi-tier CDMA Mobile Network Employing
Directional Handset Antennas
Paper 4 . 4 . 1 . 1
MAP Equalization for DQPSK in Multi-pass Demodulation
Paper 4 . 4 . 1 . 2
Achieving Flexibility in a Viterbi Decoder DSP Coprocessor
Paper 4 . 4 . 1 . 3
Analysis of Internal Data Width Requirements for SISO Decoding Modules
Paper 4 . 4 . 1 . 4
Iterative Channel Estimation for EGPRS
Paper 4 . 4 . 1 . 5
Blind Multiuser Detection in Multipath CDMA Channels with Unknown Correlated Noise
Paper 4 . 4 . 2 . 1
Error Performance Analysis of Space-Time Codes
Paper 4 . 4 . 2 . 2
A Fixed Point Approach to Wideband Amplifier Compensation for IS-2000
Paper 4 . 4 . 2 . 3
Frame Synchronization of Turbo Coded Systems Using a List-Synchronization Technique
Paper 4 . 4 . 2 . 4
Subspace Based Multiuser Detector Algorithms
Paper 4 . 4 . 2 . 5
Performance Analysis of a Narrowband Two-Signal Receiver Based on Joint Detection
Paper 4 . 4 . 3 . 1
Two-Dimensional Code Acquisition in Fixed Multipath Channels
Paper 4 . 4 . 3 . 2
Performance of Soft-Output Space-Time Equalization for EGPRS
Paper 4 . 4 . 3 . 3
Generalized RAKE Reception for Cancelling Interference from Multiple Base Stations
Paper 4 . 4 . 3 . 4
Multiuser-Macrodiversity Detection in Rayleigh Fading Channels
Paper 4 . 4 . 3 . 5
Generalized Principal Ratio Combining for Space-Time Codes in Slowly Fading Channels
Paper 4 . 4 . 4 . 1
Improved Single-User Detector for WCDMA Systems Based on Griffiths' Algorithm
Paper 4 . 4 . 4 . 2
Multiuser Detection with Partial Information for Asynchronous CDMA-Based Radio Networks
Paper 4 . 4 . 4 . 3
On the Potential of Multimode Antenna Diversity
Paper 4 . 4 . 4 . 4
Highly Efficient Large-Domain Moment-Method Analysis and CAD of Radio-Frequency
Antennas Mounted on or Situated in Vehicles
Paper 4 . 4 . 4 . 5
Channel Precoding for pi/4-DQPSK and MSK over Frequency-Selective Slow Fading Channels
Paper 4 . 5 . 1 . 1
Combined Temporal and Spatial Filter Structures for CDMA Systems
Paper 4 . 5 . 1 . 2
Iterative Demodulation and Decoding of Differential Space-time Block Codes
Paper 4 . 5 . 1 . 3
Interference Cancellation with Permutation Trellis Codes
Paper 4 . 5 . 1 . 4
DS Code Acquisition in Slowly Fading Multi-path Channel
Paper 4 . 5 . 1 . 5
Capacity and Quality Enhancement for ANSI-136 Downlink Using Interference Cancellation
and Beamforming
Paper 4 . 5 . 2 . 1
Bit Error Probability of M-ary Quadrature Amplitude Modulation
Paper 4 . 5 . 2 . 2
The Capacity Analysis of SSB/BPSK-DS/CDMA with Successive Interference Canceller
Paper 4 . 5 . 2 . 3
Performance of a Residue Number System Based DS-CDMA System over Bursty Communication
Channels
Paper 4 . 5 . 2 . 4
A Self-calibration Algorithm for an Asynchronous CDMA-Based Antenna Array
Paper 4 . 5 . 2 . 5
Multiuser Detection for Multi-Rate CDMA in Multi-Path Fading Channels
Paper 4 . 5 . 3 . 1
An Efficient Carrier Frequency Offset Estimation Scheme for OFDM System
Paper 4 . 5 . 3 . 2
A Re-Investigation of Scalar Quantization for Mobile Speech Transmission
Paper 4 . 5 . 3 . 3
Joint Channel Tracking of Co-channel Signals for IS-136 Mobiles
Paper 4 . 5 . 3 . 4
Space-Time-Block-Coded OFDM Systems with Transmit Beamformers for High-Speed Indoor
Wireless Communications
Paper 4 . 5 . 3 . 5
Variable Length Equalisers for Broadband Mobile Systems
Paper 4 . 5 . 4 . 1
Investigation of Two-Branch Transmit Diversity with Two-Branch Receive Diversity in
Micro Cellular Environments
Paper 4 . 5 . 4 . 2
Efficient Algorithm for Adjustment of Adaptive Predistorter in a Transmitter for OFDM
Signals
Paper 4 . 5 . 4 . 3
Full Exploitation of Diversity in Space-time MMSE Receivers
Paper 4 . 5 . 4 . 4
Iterative Detection for Rayleigh Space-Time Channels
Paper 4 . 5 . 4 . 5
PCC: Principal Components Combining for Dense Correlated Multipath Fading Environments
Paper 4 . 6 . 1 . 1
Call Admission Control Algorithm for CDMA Systems with Adaptive Antennas
Paper 4 . 6 . 1 . 2
Transmit Diversity Schemes for Broadband Mobile Communication Systems
Paper 4 . 6 . 1 . 3
An Adaptive VCT Based Handoff Scheme for Mobile Base Station in ATM Network
Paper 4 . 6 . 1 . 4
IN Service Management in IMT-2000 Network
Paper 4 . 6 . 1 . 5
Mobile Multimedia Platforms
Paper 4 . 6 . 2 . 1
Channel Based Adaptive Resource Allocation at the MAC Layer in UMTS TD-CDMA Systems
Paper 4 . 6 . 2 . 2
The NLOS Error Mitigation Techniques for Position Location Using IS-95 CDMA Networks
Paper 4 . 6 . 2 . 3
Performance of 64 kbit/s Data Transmision with the ARQ Protocol of the DECT Standard on
Fading Channels
Paper 4 . 6 . 2 . 4
Complexity-Performance Trade-offs in Turbo Codes for IMT-2000
Paper 4 . 6 . 2 . 5
A High Channel Efficiency Transceiver Based on Direct Access Frequency Synthesis
Technique
Paper 4 . 6 . 3 . 1
Adaptive Quantization for Third-Generation TDMA Transmitters
Paper 4 . 6 . 3 . 2
Automatic Base Station Selection and Configuration in Mobile Networks
Paper 4 . 6 . 3 . 3
Effects of Power Control Errors and Multipath Fading on BER in a Cellular CDMA System
Paper 4 . 6 . 3 . 4
Finding User Position Location Using the Doppler Information in Satellite CDMA Systems
Paper 4 . 6 . 3 . 5
An Integrated Approach for Performance Modeling and Evaluation of Soft Handoff in CDMA
Mobile Cellular Systems
Paper 4 . 6 . 4 . 1
Potential Physical Layer Enhancements for AMR Speech over EDGE
Paper 4 . 6 . 4 . 2
Uplink Capacity of FFF W-CDMA Mode in UMTS Networks for Mixed Services
Paper 4 . 6 . 4 . 3
A Traffic dispersion Strategy in Fiber-optic Multitier Cellular System
Paper 4 . 6 . 4 . 4
Channel Estimation Using Short Training Sequences
Paper 4 . 6 . 4 . 5
Joint Deployment of Macrocells and Microcells over Urban Areas with Spatially
Non-Uniform Traffic Distributions
Paper 4 . 7 . 1 . 1
Optimization of Power Management in a CDMA Radio Network
Paper 4 . 7 . 1 . 2
System Level Performance Evaluation of GPRS for Various Traffic Models
Paper 4 . 7 . 1 . 3
System Level Performance Evaluation of EGPRS in GSM Macro-Cell Einvironments
Paper 4 . 7 . 1 . 4
Performance Studies of Rate Matching for WCDMA Mobile Receiver
Paper 4 . 7 . 1 . 5
A Call Admission Algorithm with Optimal Power Allocation for Multi Class Traffic in
CDMA Systems
Paper 4 . 7 . 2 . 1
An Analysis of the 3-Stage Search Process in W-CDMA
Paper 4 . 7 . 2 . 2
Adaptive Path Selective Linear Multipath-Decorrelating Receiver for CDMA
Frequency-Selective Fading Channels
Paper 4 . 7 . 2 . 3
GPS-Based Message Broadcast for Adaptive Inter-Vehicle Communications
Paper 4 . 7 . 2 . 4
Multi-Cell WCDMA Signal Processing Simulation
Paper 4 . 7 . 2 . 5
Enhanced Capacity Management for 2nd and 3rd Generation Cellular Networks
Paper 4 . 7 . 3 . 1
Teletraffic Modelling and Performance Evaluation in Multilayer Cell Architecture
Paper 4 . 7 . 3 . 2
CDMA2000 Reverse Link: Design and System Performance
Paper 4 . 7 . 3 . 3
Performance Enhancements for the GSM/EDGE Radio Access Network
Paper 4 . 7 . 3 . 4
Performance Optimization of Single Frequency Broadcast Systems in FDD-CDMA Cellular
Bands for Wireless Multimedia Services
Paper 4 . 7 . 3 . 5
Voice Enabled Request and Response for Mobile Devices Supporting WAP Protocol
Paper 4 . 7 . 4 . 1
Effects of Fading Correlation on Multiple Antenna Reception Mobile OFDM Systems
Paper 4 . 7 . 4 . 2
A Novel Deregistration Strategy for Mobile Networks
Paper 4 . 7 . 4 . 3
The Performance of the M-ary DS/CDMA Cellular
System over Rayleigh-Fading Channel with a Hybrid
EGC-SC Scheme
Paper 4 . 7 . 4 . 4
Capacity Comparison of Turbo and Convolutional Codes in Multi-cell DS-CDMA Systems
Paper 4 . 7 . 4 . 5
Multi-antenna Wireless Base Stations in TD/CDMA Communications Systems
Paper 4 . 8 . 1 . 1
Effect of the Cell Size and the Path Loss Model on the GSM Erlang Capacity for
Microcellular Environments
Paper 4 . 8 . 1 . 2
Turbo-coded Error Control for Wireless ATM Networks
Paper 4 . 8 . 1 . 4
Blind Decision Feedback Equalizer with Tracking Ability in Severe Propagation
Conditions
Paper 4 . 8 . 1 . 6
A Suitable Set Partitioning Method For MTCM with Biorthogonal Symbol Sets
Paper 4 . 8 . 1 . 7
Postdetection Diversity Receiver for DAPSK Signal over the Rayleigh and Rician Fading
Channel
Paper 4 . 8 . 1 . 8
The Effect of Branch Correlation in Dual MRC, SC and SWC Diversity Systems for
Noncoherent MFSK over Nakagami-m Fading Channels
Paper 4 . 8 . 1 . 9
Multi-Channel (Blind) Equalization for TDMA Cellular Systems
Paper 4 . 8 . 1 . 10
Analysis of Iterative Decoding for Serial Concatenated Convolutional Codes
Paper 4 . 8 . 1 . 11
Multicarrier CDMA Systems with Transmit Diversity
Paper 4 . 8 . 1 . 12
The Adaptive Least Mean Square Algorithm Using Several Step Size for Multiuser
Detection
Paper 4 . 8 . 1 . 13
Space-Time Multistage Parallel Interference Cancellation for CDMA
Paper 4 . 8 . 1 . 14
Code Acquisition System Using Periodic Property of PN Code in Rayleigh Fading Channel
Paper 4 . 8 . 1 . 15
An Adaptive Channel Estimation Scheme for DS-CDMA Systems
Paper 4 . 8 . 1 . 16
Multi-user Detection Using CMA & The Cancellation Method In Fast-Fading Channels
Paper 4 . 8 . 1 . 17
Performance of Coherent Square M-QAM with Lth order Diversity in Nakagami-m Fading
Paper 4 . 8 . 1 . 18
The General Procedure For Designing a MTCM Scheme With Biorthogonal Symbol Sets
Paper 4 . 8 . 1 . 19
SDR-Based Digital Channelizer/De-Channelizer for Multiple CDMA Signals
Paper 4 . 8 . 1 . 20
A Fast Software Method of Decorrelating Multiuser Detector in W-CDMA System
Paper 4 . 8 . 1 . 21
Integrated Design of Adaptive Receivers and CDMA/PRMA Multimedia Medium Access Scheme
Paper 4 . 8 . 1 . 22
An Efficient Call Admission Control for QoS Provisioning in Wireless Networks
Paper 4 . 8 . 1 . 23
Determining Optimal Numbers of Traffic Channels in BS and Vocoders in MSC
Paper 4 . 8 . 1 . 24
Capacity Analysis of a UTRA-TDD System
Paper 4 . 8 . 1 . 25
Edge Compact Control/Data Bandwidth Dimensioning
Paper 4 . 8 . 1 . 26
Outage Probability of a Multicarrier DS/CDMA System with Adaptive Antenna Array
Paper 4 . 8 . 1 . 27
A New Adaptive Routing Scheme Based on the Traffic Characteristics in Mobile Ad-hoc
Networks
Paper 4 . 8 . 1 . 28
Blocking Performance Evaluation of Link between MSC's for CDMA Inter-MSC Soft Handoff
Paper 4 . 8 . 1 . 29
Design of Semi Blind Decision Feedback Equalizer with Short Training Sequence
Paper 4 . 8 . 1 . 30
Dynamic Rate Control Based on Interference and Transmission Power in 3GPP WCDMA System
Paper 4 . 8 . 3 . 1
Mobile Network Traffic Forecasting
Paper 4 . 8 . 3 . 2
A New Multimedia Network Architecture Using 3G CDMA2000
Paper 4 . 8 . 3 . 3
Effect of Various Threshold Settings on Soft
Handoff Performance in Various Propagation Environments
Paper 4 . 8 . 3 . 4
Simple Nonlinear GMSK Receiver for Multipath Environment
Paper 4 . 8 . 3 . 5
An Implementation Method of a Turbo-code Decoder Using a Block-wise MAP Algorithm
Paper 4 . 8 . 3 . 6
MAP-Algorithm with Fixed-Point Representation for Software Radios
Paper 4 . 8 . 3 . 7
Noise-reduced GMDF for Acoustic Echo Cancellation in Mobile Environments
Paper 4 . 8 . 3 . 9
Adaptive Dynamic Channel Allocation Scheme for Wireless Multimedia
Paper 4 . 8 . 3 . 10
Robust DFE for Limiter-Discriminator Based HIPERLAN Receivers
Paper 4 . 8 . 3 . 11
Hybrid Linear and Non-linear PIC for WCDMA
Paper 4 . 8 . 3 . 14
Signal-strength-based Cellular Location Using Dynamic Window-width and Double-averaging
Algorithm
Paper 4 . 8 . 3 . 15
Wireless Data Transmission for High-Speed Train Control
Paper 4 . 8 . 3 . 18
An Investigation of Inter-cell Interference in UTRA-TDD System
Paper 4 . 8 . 3 . 21
Techniques to Provide Coverage and Capcity in GSM Pico-cell Environment
Paper 4 . 8 . 3 . 22
Comparison of Indoor Geolocation Methods in DSSS and OFDM Wireless LAN Systems
Paper 4 . 8 . 3 . 23
Adaptive Antenna Algorithms for Multimedia Communications
Paper 4 . 8 . 3 . 26
Estimating the Gains of Adaptive Antenna Systems for GPRS and EDGE Data Services in
GSM Networks
Paper 4 . 8 . 3 . 29
Flexible Security and a New Structure for Electric Commerce on Software Radio
Paper 2.1.2.1
Tapped Delay Line Channel Models at 5.3 GHz in Indoor Environments
Based on more than 100,000 impulse responses collected in severval buildings in indoor environments, the tapped delay
line channel models are developed and the statistical characteristics for each tapped line is analysed in detail.Based
on the models, the wideband and narrowband channel transfer functions can also be calculated.The results would be useful
for the designing of RAKE receiver and indoor mobile communications systems at 5 GHz frequencies.
Paper 2.1.2.2
Spatial and Temporal Characteristics of 60 GHz Indoor Channels
This paper presents measurement results and models for 60 GHz channels.A total of 33 locations in eight different
environments are measured at Virginia Tech.Multipath components are resolved in time by using a sliding correlator with
10 ns resolution, and in space by spinning a directional antenna with $7^\circ$ half power beamwidth.Power delay
profiles (PDP) and power angle profiles (PAP) are measured in various indoor and short-range outdoor environments.PDP
records temporal power distribution over multipath time-of-arrival (TOA), and PAP records spatial power distribution
over multipath angle-of-arrival (AOA).Detailed multipath structure is retrieved from PDPs and PAPs, and compared with
site-specific environments.Results show strong correlation between the propagation environments and multipath
structure.From the recorded 8,848 wideband PDPs and 94 PAPs, received signal power, statistical TOA and AOA parameters
are estimated.The high resolution measurements provide great insights into millimeter-wave channel and basis for
advanced space-time channel modeling and ray tracing developments.The measured statistical TOA and AOA paramenters also
present pragmatic values for broadband wireless system design over 60 GHz short range channels.
Paper 2.1.2.3
Experimental Investigations of Correlation Properties of MIMO Radio Channels for
Indoor Picocell Scenario
Measurement results of the correlation properties of MIMO radio channels are presented.The intra/inter-correlation
between the antenna array elements is experimentally investigated for indoor picocell where Line-Of-Sight (LOS) and
Non-Line-Of-Sight (NLOS) is considered.At both end of the communication link, several antenna topologies will
investigated along with the use of polarization diversity in order to illustrates solutions to countermeasure the
fluctuation of the correlation matrix and thus aiming at a more robust system.
Paper 2.1.2.4
Indoor and Outdoor Measurements of Space, Polarization, and Angle Diversity for
Cellular Base Station in Urban Environments
Indoor and outdoor measurements of space, polarization, and angle diversity for a cellular base station operating in
urban environments were performed under the identical conditions.Measurements with three orientations of the mobile
unit antenna were performed at various locations and distances.Diversity gains for the three diversity antenna schemes
are compared, as well as signal level improvements for polarization and angle diversity compared to the reference
antenna.
Paper 2.1.2.5
Simple and Accurate Path Loss Modeling at 5 GHz in Indoor Environments with Corridors
In order to assess path loss characteristics in typical WLAN scenarios extensive measurements have been performed at 5.2
GHz (a frequency in the HIPERLAN type 2 band) in one modern office building and in a school built in 1950.Moreover, it
has been investigated if any simple model accurately could describe the measurement data.One simple modeling approach
turned out be remarkably accurate.The standard deviation of measured loss relative to this model is between 2 and 4 dB.
Paper 2.1.3.1
Impact of Human Shadowing on Temporal Variation of Broadband Indoor Radio Channel
Characteristics and System Performance
Results of a comprehensive campaign of measurement to study the effect of moving people on the temporal variation of 5GHz
indoor radio propagation characteristics are presented.The measurements consider the impact of various shadowing
conditions on the fundamental channel parameters such as received signal strength, RMS delay spread and K-Factor as well
as the effects on the quality of a digital transmission link in terms of Bit Error Rate for a multi-rate single carrier
QPSK modem.Impact of directional antennas at one or both ends of the link are also studied.It is shown that shadowing
significantly increases the short time variations of the channel characteristics, which subsequently impairs the
performance of the digital system operating under such conditions.The results provide much needed information for more
accurate modelling of practical indoor radio channels.
Paper 2.1.3.2
Pedestrian-Induced Fading for Indoor Channels at 2.45, 5.7 and 62 GHz.
At UHF and above, shadowing effects caused by the movement of personnel become significant in short-range indoor radio
channels.This paper examines pedestrian-induced fading characteristics at key frequencies within the microwave band;
consideration is given to the effects of wave obstruction by the human body - reflection, diffraction and transmission.
Fading profiles are reported for a point-to-point link in a 150 m-sq open-plan environment.Irrespective of frequency,
received power levels fluctuated by 33 dB and fading was flat with a bandwidth of less than 2 Hz.
Paper 2.1.3.3
Monte Carlo Simulation of Delay and Angle Spread in Different Building Environments
Advance radio system designs have been proposed that are intended to overcome or take advantage of the impairments of the
radio channel caused by multipath effects in urban environments.The design of such systems and their evaluation requires
knowledge of higher order channel statistics.For example, the design of smart antenna systems requires knowledge of the
delay spread and angle spread in the environment where the system is to function.The delay and angle spreads have been
measured at individual locations in a few cities.However, it is not clear if the measured results are widely applicable
to other building environments.To overcome this limitation, we have used the 3D ray tracing code, called the VPL method,
to simulate channel statistics.Our goal is to relate the variation of statistical properties of the radio channel to the
statistics of the building environment, and to the geometry of the radio link.Simulations have been run to find the
influence of the statistical parameters describing the building distribution and on delay and angular spreads.
Paper 2.1.3.4
Detailed radio imaging of buildings at 2.4 GHz
In the following study, we resolve a radio image reflected off a building to a resolution of 4-5 m, and identify
contributions to the channel impulse response with detailed geometrical features of the environment that correspond to
individual ray-optical interactions.We finally discuss briefly the validity of the common assumptions made by
ray-tracing tools in the light of these results.The radio imaging measurement system, used for measurements, was based
upon the vector network analyzer (VNA) technique in which the receive antennas were scanned over a volume to form a
synthetic aperture for multipath angle-of-arrival (AoA) determination.The frequency domain measurements were converted
into the delay domain using conventional fast Fourier transform techniques.The resulting CIRs were time gated and the
AoA as a function of delay was determined using robust matched filtering techniques.The measurements presented in this
paper used a centre frequency of 2.440 GHz with a bandwidth of 80 MHz giving multipath delay resolution on the order of
4-5 m.The synthetic aperture was configured to provide azimuth angular resolution of the order of 10o, and elevation
resolution of the order of 30 o.
Paper 2.1.3.5
The Bluetooth Channel
The Bluetooth channel is new in the sense that it is very short range and communication between relatively slowly moving
or stationary terminals.Channel measurements for typical Bluetooth channels have been made with a four channel
sounder.One end of the link is a two antenna card in a notebook used for transmit whereas the reciving terminal was a
small devise with two antennas which was placed in different orientations and even carried by a person.The results shows
that low correlations can be obtained between the two antennas.Furthermore that the coherence bandwidth is higher than
the total Bluetooth bandwidth in 20 to 50% of the time.This means that the frequency hopping included in the system does
only combat interference and not suppres multipath fading.
Paper 2.1.4.1
Closed-loop transmit diversity techniques for multi-element transceivers
The transmit diversity concept adopted for the FDD mode of the third generation WCDMA system in 3G standardization is
currently optimized for the case where there are two transmitting elements in the base station.Then, the open-loop mode
applies a space-time block code for two transmit antennas, and the closed-loop mode has two sub-modes which both use
feedback-based weight to approximate matched beamforming.In this paper we propose backward compatible generalizations to
the feedback modes which are applicable in the presence of an $M$-element array.Different concepts that reduce the
capacity of the feedback signaling are introduced.
Paper 2.1.4.2
Performance of Downlink Nulling in Combined Packet/Circuit Switched Systems
Downlink beamforming is the limiting factor in the application of adaptive antennas in cellular mobile communication
systems.Directing nulls of the antenna pattern to active mobiles in the downlink will be impossible in the case of
packet data transmission (e.g.GPRS/EDGE).But in the evolution of 2nd generation mobile communication systems packet
switched data transmission and circuit switched speech communication will be used in parallel.We will show by link level
simulations, that also in combined packet/circuit switched mobile communication systems smooth downlink interferer
nulling will lead to performance and capacity improvement.The interference suppression due to smooth nulling of the
circuit switched users outperform by far the loss in the antenna gain and therefore the interference increase for the
packet data users.
Paper 2.1.4.3
A Study of Polarization Diversity Using an Electromagnetic Spatio-Temporal Channel
Model
Future wireless systems will most likely use several types of diversity in order to meet the quality demands.To
accurately exploit different types of diversity, a detailed radio channel model is needed.An electromagnetic based
spatio-temporal channel model that includes many of the propagation phenomena encountered in practice is introduced.This
model will then be used to examine the polarization diversity gain for different antenna arrangements using a vector
RAKE receiver.The impact of the inclination of the mobile antenna will also be considered.
Paper 2.1.4.4
Link-Optimal BLAST Processing with Multiple-Access Interference
Recent information theory results have demonstrated the enormous capacity potential of wireless communication systems
with multiple transmit and receive antennas.To exploit this potential, a number of layered space-time (BLAST)
architectures have been proposed which transmit parallel data streams, simultaneously and in the same frequency band, in
a multiple-input multiple-output fashion.With sufficient multipath propagation, these different streams can be separated
at the receiver.Mostly, these space-time schemes have been studied only in the presence of spatially white noise.In
this letter, we present an architecture that is optimal, in the sense of maximizing the link spectral efficiency, in the
presence of spatially colored interference.We evaluate this new architecture and compare it, under various propagation
conditions, to other adaptive-antenna techniques with equal number of antennas.
Paper 2.1.4.5
Space-Time Coding for UMTS.Performance Evaluation in Combination with Convolutional
and Turbo Coding
Space-time codes provide both diversity and coding gain when using multiple transmit antennas to increase spectral
efficiency over wireless communications systems.Space-time block codes have already been included in the standardization
process of UMTS in conjunction with conventional channel codes (convolutional and turbo codes).We discuss different
decoding strategies when transmit diversity is combined with conventional channel codes, and present simulations results
for the TDD and FDD modes of UTRA.
Paper 2.2.2.1
Space Hopping Scheme Under Short Range Rician Multipath Fading Environment
An array antenna system reuires as the same number of RF circuit sections as that of antennas.This papere presents the
novel concept of Space Hopping which requires only one RF circuit and shows favorable BER characteristics for the array
antenna system.Also, we focus on the improvement of BER in the array antenna configuration under a short range Rician
distribution multi-path fading environment.A multipath simulation bench is studied and designed to evaluate the space
hopping performance.Several simulation are made to confirm the performance of the space hopping and obtain a good
configuration of the array antenna.
Paper 2.2.2.2
Coherent Interference Suppression with an Adaptive Array Using Spatial Affine
Projection Algorithm
Conventional adaptive beamforming methods exhibit signal cancellation phenomena when the interferers are highly
correlated with the desired signal.In this paper, we propose a new adaptive beamforming algorithm for multiple coherent
interference suppression, which utilizes the Affine Projection Algorithm in space domain (SAP).The proposed SAP
algorithm outperforms the existing time averaging algorithms with faster convergence and deeper nulls in the beam
pattern, because the projection of the SAP algorithm provides additional decorrelation comparing to simply subgrouping.
The computational complexity of the SAP algorithm is close to that of the other schemes using the NLMS adaptation
algorithm.
Paper 2.2.2.3
Investigation of the trade-off characteristics of beamforming performance in DS-CDMA
system
This paper presents the analytic derivations and the operation simulations of the SINR behavior when a linear array
antenna is accommodated into the cellular CDMA basestation with beamforming(BF) algorithms.The roles of the two major
performance-effecting design factors, i.e., the direction selectivity of an array antenna and the direction-of- arrival
(DOA) precision in BF algorithm, are investigated not only in view of the SINR itself but also in view of the BF
algorithm's robustness to the erroneous factors of spatial scattering of radio waves and DOA error.It is confirmed from
this study that there exists a trade-off characteristics between the SINR and the robustness with respect to the above
two design factors.The trade-off characteristics can be capitalized to obtain an economic means of BF implementation for
cellular CDMA system which does not severely deteriorate SINR performance while ensuring its robustness to the erroneous
factors.
Paper 2.2.2.4
Downlink capacity of multirate DS-CDMA with antenna array and SIR based power control
in multicell environment
Capacity is one of the most critical performance targets in the CDMA system and has been investigated widely in recent
years.To further improve the capacity, many effective approaches are introduced, such as the antenna array and SIR based
power control.Furthermore, the third generation CDMA network will be a multimedia multi-rate system.In this paper, a
theoretical model is developed to study the downlink capacity performance.Also from the numerical results, major system
parameters affecting the capacity will be analysed as well.
Paper 2.2.2.5
Non-stationary Interference Exciser in Smart Antenna Systems Using an Adaptive Gabor
Expansion
Since smart antenna systems which employ spread spectrum methods are sensitive to a time-correlated non-stationary
jammer, precise excision of the jammer noise is required.To remove this non-stationary jammer, we propose, in this
paper, a new adaptive Gabor noise exciser, which can track optimally the change of the time and frequency densities of
the jammer.To find the optimum time-frequency Gabor expansion for the received signal, we utilize the optimum
projection method.In the time-frequency Gabor domain, we remove the non-stationary jammer, and reconstruct the
jammer-free signal from the remining Gabor coefficients.This approach exhibits better performance than the
non-optimized Gabor transform exciser.
Paper 2.2.3.1
An Adaptive Array Antenna for cdma2000 System
In this paper, we present an inexpensive adaptive array antenna algorithm for a 3rd generation CDMA system, i.e.,
cdma2000.Our algorithm not only can track the desired user*s direction of arrival angle (DOA), but also can estimate
the fading phase.As a result, the channel estimation is not required in this paper.Furthermore, the phase distortion
due to the RF mixer in each sensor is compensated automatically by our algorithm.BER results of the proposed algorithm
are compared with the standard normalized least mean square (N-LMS) algorithm.The proposed algorithm shows better BER
results than the standard N-LMS algorithm.
Paper 2.2.3.2
Phase and Amplitude Calibration of a PCS Wideband Antenna Array
Current research efforts for next generation mobile systems are focusing heavily on advanced antenna arrays to improve
system capacity.To this end, algorithms are being developed which calculate complex weighting factors used for beam
shaping and steering.These algorithms require that the relative phase between receiver channels be stationary.However,
effects such as cable heating and oscillator phase noise can cause fluctuations.To compensate for relative phase
stability between receiver channels a reference channel can be used.This paper investigates parameters which determine
the phase stability of a system and the use of a reference channel.It also presents data collected using a multichannel
broadband receiver developed for advanced antenna algorithm testing.Phase data collected in the laboratory is
contrasted with field data using a remote reference at 1.92 GHz.Results are analyzed and compared with theory.
Paper 2.2.3.3
Capacity enhancement based on using adaptive antenna arrays optimized for trunking
efficiency
Analytical and simulation analysis is developed to study the impact on spectral efficiency when the adaptive antennas at
the base stations in a cellular network maximize trunking efficiency.In order to maximize trunking efficiency, the
adaptive antenna array is used to extend the coverage range over an omni directional antenna.The extension in range is
then used to optimize the base station to mobile assignment in order to minimize the number of mobiles blocked.Based on
simulation results an increase in system capacity by 2 to 4 times may be achieved using this approach.
Paper 2.2.3.4
Optimum element arrangement of adaptive base station antennas for SDMA in circular
cell
Space division multiple access (SDMA), which enableenables multiple users to use a communication channel by utilizing
adaptive base station antennas, is an attractive candidate for enlarging the channel capacity of mobile communication
systems.This paper derives the mathematical formula of an average squared spatial correlation (ASSC) that determines the
optimum element arrangement of the adaptive base station antennas for the SDMA, which discriminates between two users in
a circular zone.The optimum array configurations for a linear array and a circular array are clarified.As the
results, the optimum inter-element spacing for linear array appears at 0.4-wavelength and approximately 0.5-wavelength
intervals.The optimum spacing does not depend on the number of elements.The optimum array radius for the triangular
array (N = 3) appears at 0.2-wavelength and approximately 0.3-wavelength intervals.When the number of elements is
increased, the interval obtaining the minimum ASSC becomes long.The optimum radii are 0.96 and 1.27 wavelength for 4
and 8 element arrays, respectively when the array radius is less than 1.5 wavelength.
Paper 2.2.3.5
Adaptive Antennas in WCDMA systems; Link level simulation results
In this contribution, some results regarding a single cell WCDMA (UMTS-FDD) system is presented.A single cell equipped
with an adaptive antenna is studied.Simulation results of different up- and downlink algorithms are presented, where the
expected behavior of users within a cell plays an important role.These scenarios includes the most typical cases
expected to occur in macro cell environments.The scenarios includes typical urban, suburban and rural environments, and
also special cases are investigated, e.g., highways and hotspots such as shopping malls etc.
Paper 2.2.4.1
Match filter bound analysis used to evaluate range increase provided by an adaptive
antenna array
An analytical approach is developed for evaluating the expected range increase and variations in coverage range while
using an M-element adaptive antenna array at the BS.The analysis is based on the match filter bound on the bit error
rate probability for a frequency non-selective Rayleigh fading channel.Results for a ten element uniform linear array
indicate the range can be nearly doubled over a BS with only a single antenna.
Paper 2.2.4.2
FDD DS-CDMA downlink beamforming by modifying uplink beamforming weights
Two new algorithms are proposed for downlink beamforming in FDD DS-CDMA mobile radio by using uplink beamforming weights.
One is null constrained (NC) method, which constrains same null positions for both links' beam patterns; the other is
frequency calibrated (FC) method, which constrains same main beam's positions for both patterns.These algorithms are
simple in implementation and computation.Simulations have shown that the new algorithms can support much higher system
capacity than traditional DOA-based approaches.
Paper 2.2.4.3
Hybrid Adaptive Algorithm Based on Temporal Update and Spatial Spectrum Estimation for
Adaptive Array Antenna
Both classes of adaptive algorithm based on temporal update, e.g.LMS and spatial spectral estimation, e.g.DFT have
advantages and disadvantages relatively.In order to compensate for their problems with maintaining advantages, this
paper proposes and investigates an adaptive array antenna using combined DFT and LMS algorithm.The proposed combined
or hybrid algorithm can improve convergence speed of weight coefficients in temporal updating algorithm and accuracy of
weight coefficients in spatial spectral estimation algorithm.
Paper 2.2.4.4
Soft Handoffs in Code Division Multiple Access Systems with Smart Antenna Arrays
Soft Handoffs are an important part of Code Division Multiple Access (CDMA) systems.With the increasing interest in
smart antenna systems, the issue of soft handoff needs to be addressed for CDMA systems with smart antenna systems.This
paper presents an analysis of smart antenna coverage and soft handoffs in a CDMA system.This paper will also show
the relevance of soft handoffs on the system capacity.It is well known that smart antennas improve the capacity of a
CDMA system by reducing interference at the receiver.But the soft handoff region increases due to the non-uniform
receiver gain in smart antennas.These two issues combined with a limited number of forward link channels turns a CDMA
system from a reverse link limited system to a forward link limited system.However, with appropriate cell sector
orientation, the soft handoff region coverage can be optimized while maintaining an appropriate margin.This will then
optimize the soft handoff region size and t! he overall system capacity.It will be shown that cell sector orientation,
with smart antennas, closely approximates the Interleaved Narrow Beam Tri-sector Cell (INBTC) architecture.
Paper 2.2.4.5
Semi-blind method for adaptive transmit antenna array for CDMA systems
Down-link beamforming with transmit antenna array (TAA) can improve the performance of wireless communication systems.
Utilizing spatial properties of the wireless channel, we proposed semi-blind down-link beamforming method with TAA for
code division multiple access (CDMA) systems in this paper.In semi-blind method, feedback delay can cause performance
degradation in a time-varying fading channel environment.To overcome this difficulty, the prediction has been
considered.Furthermore, the performance of TAA has been analyzed with upper and lower bounds for the bit error
probability in a fading channel environment.
Paper 2.3.2.1
Joint Design of Adaptive Channel Coding and Multiple Access Control for Integrated
Voice and Data Services in a Cellular Wireless Network|With Contention Queue
A new MAC protocol employing a joint design of the multiple access control (MAC) layer and the physical layer is proposed
for cellular wireless systems with integrated voice and data services.This is a novel concept and is shown to achieve
very significant gains (in capacity, packet loss and delay) compared to existing protocols through the exploitation of
the synergy between the two protocol layers.
Paper 2.3.2.2
A novel multiuser transmission scheme requiring no channel estimation and no
equalization at the mobile stations for the downlink of TD-CDMA operations in the TDD
mode
In this paper, a novel multiuser technique is presented for directly determining the total transmitted signal of one base
station in order to serve a number of mobile stations (MSs).Each MS is assumed to use a single matched filter (MF) only,
which is matched to a MS specific spreading code.Based on the exact of approximate knowledge of the relevant channel
impulse responses, the transmitted signal is chosen this way, to compensate the influence of ISI and MAI at the location
of each MS.Consequently the MS specific data symbols can directly be taken from the outputs of the MFs without any
necessary equalization.This technique achievs two goals: First, no training sequences are used, thus significantly
increasing the data rate and simplifying the receiver structure at the MSs.Second, a single MF is used at each MS, thus
requiring no equalization.
Paper 2.3.2.3
Multichannel CSMA with Signal Power-Based Channel Selection for Multihop Wireless
Networks
A random access scheme suitable for multihop wireless networks is proposed that uses multiple channels and a dynamic
channel selection mechanism.Channel selection is based on local measurements of signal power on all the channels.A
protocol similar to CSMA/CA (carrier sense multiple access with collision avoidance) is adapted on the chosen channel.
The proposed scheme reduces the effect of interference, thereby reducing the probablity of packet collisions.Detailed
simulation results are presented showing the effectiveness of the scheme.
Paper 2.3.2.4
A MAC Algorithm for Energy-limited Ad-hoc Networks
An ad-hoc wireless network consists of mobile terminals forming a temporary network without any deployed infrastructure
or centralized administration.A general constraint common to many ad-hoc networks lies in the short lifetime of mobile
terminal batteries.Hence, energy efficient protocols are needed to reduce the effect of this constraint.In this paper,
we propose a MAC algorithm with high energy efficiency for CDMA-based ad-hoc wireless networks.A proposed MAC algorithm
is based on scheduling method that informs each terminal when to wake up from sleep mode or when to go to sleep for its
power saving.We perform a simulation to evaluate delay, fairness, through, and energy efficiency as metrics of our MAC
protocol.It can be used in multimedia classes, military operations, and robot cooperation in inland places.
Paper 2.3.2.5
Extending Earliest-Due-Date Scheduling Algorithms for Wireless Networks with
Location-Dependent Errors
Generalized processor sharing (GPS) and earliest-due-date (EDD) algorithms are two work conserving service disciplines
to provide bounded delay and fair scheduling on wired networks.Unfortunately, these algorithms can not be directly
applied to wireless networks due to the location-dependent errors in mobile environment.A number of previous studies
enhanced GPS-like algorithms to accommodate to the wireless environment.Unlike GPS-like algorithms which guarantee a
delay bound based on the weight that is tightly coupled to a reserved service rate, EDD and its extensions such as
delay-EDD and jitter-EDD policies allow for the separation of delay, delay-jitters and throughput guarantees for a
particular data flow.However, studies of EDD scheduling algorithms on wireless network are almost ignored.In this
paper, we explore EDD and delay-EDD policies, and present their extensions.The proposed algorithms can achieve short
term and long term fairness, and QoS guarantee! s on wireless networks.
Paper 2.3.3.1
A Queuing Priority Channel Access Protocol for Voice/Data Integration on the Air
Interface of Microcellular Mobile Radio Networks
The explosive growth in mobile communications market over the last decade demonstrates the enormous demand for
communications mobility.This demand is paralleled by a proliferation of tetherless portable computing devices and a
surge in data services usage.Therefore, we are faced with the challenge of incorporating data into networks that were
originally designed for voice.In order to jointly carry this extraordinary growth of a wide range of services over the
air interface of the mobile radio network, advanced microcellular technology with intelligent channel assignment
protocols should be adopted.Microcells are characterised by their massive capacity, low power requirements, equipment
miniaturisation, flexible deployment and high spectral efficiency.However, working with microcells results in an
unbounded handovers due to the high rate of microcell boundary crossing by active mobile stations (MSs).The current
paper introduces a new concept of dynamic length microcellular structure.The highway microcellular mobile radio network
is considered as a case study.The microcell length can be designed in order to be adaptable to the number of mobile
users in a microcell that is basically dependent on the prevailing vehicular traffic flow.It is, therefore, possible
to arrange for the network to accommodate all users roaming in its service area under any traffic situation.This can be
arranged by deploying redundant base stations (BSs) on the lamp posts and implementing vehicular traffic sensors along
the highway.The BSs are connected by a token passing bus local area network that is controlled by a base station
controller (BSC) or a mobile switching center (MSC).The output of the sensor is used as a controlling signal.The
controller determines the optimum microcell length according to the traffic flow and transmits a suitable supervisory
packet to the appropriate BSs in o! rder to switch on their transceivers with the convenient transmitted power.The
layout characteristics of the microcellular structure is addressed and the required cluster size as a function the
attainable carrier to interference ratio (CIR) is discussed.In addition, the paper proposes a queuing priority channel
assignment protocol suitable for the integration of voice and data traffic on the air interface of a microcellular
mobile radio network.As voice calls are time-critical and the interruption of a conversation is unbearable, the
strategy aims at minimising this phenomena.The access of a voice call attempt is handled on of a blocked calls cleared
basis.Data traffic, on the other hand, are served on a delay basis as the prompt delivery of data is not stringent.
Therefore, the strategy satisfies the service quality requirements for both voice and data traffic.A new voice call
attempt is allowed access to (Nc =N- Nh) channels out of the N channels assigned to the microcell.A handover voice
attempt can access all the N channels of the microcell.Should a voice handover is attempted while all of the N channels
being busy, the attempt is allowed to join a queue waiting for a channel in a first come first served basis.I! f the
waiting voice handover attempt cannot get a channel prior to link deterioration, the call is forced to terminate.In
contrary, an attempt to initiate a data session or to handover a data service when finding all the microcell channels
being busy, joins the queue and waits until either a channel becomes available or the MS moves out the current microcell
to the next microcell.With this approach, data traffic suffers no blocking but encounters queuing delay.A data
session, in this sense, may be interrupted and resumed many times during its lifetime.A methodology is developed for an
accurate teletraffic modelling of the network when adopting the strategy.The traffic model is based on more realistic
and sound concepts such as the evidently finite number of users roaming in a microcell as well as the impact of
vehicular traffic flow on the communication load.In addition, the effect of the hostile mobile radio channel on data
transmission is considered.The probability of a successful data transmission as well as the overall data rate due to
retransmission of erroneous packets are addressed.Handover traffic of both voice and data sources, handover priority,
Paper 2.3.3.2
Demand Assignment Multiple Access Protocols for Wireless ATM Networks
This paper describes Demand Assignment Multiple Access (DAMA) protocols and their application in wireless ATM networks.
Performance of diiferent DAMA protocols is evaluated and the results are compared by using simulation.
Paper 2.3.3.3
Wavelet Packet Function Based RAKE /Adaptive Multichannel DFE Equalization for WPMA
System over Frequency Selective Rayleigh Fading Channels
Wavelet Packet function based Multiple Access system (WPMA) is a multiple access method proposed to increase system
capacity several years ago.When such a system is applied to transfer messages over frequency selective/slowly fading
channels, significant Intersymbol Interference(ISI),as well as severe MAI,emerges to degrade the performance greatly.To
compensate for such impairments and improve system performance,we design a wavelet packet based RAKE(WP RAKE) to reduce
ISI and, a SISO/MISO, which follows the WP RAKE, to suppress MAI encountered.Theoretical analysis and simulation results
show that our proposed receiver is very effective in combatting frequency selectivity of a multipath channel while
having a relatively low complexity.
Paper 2.3.3.4
QoS Guarantees for Third Generation (3G) CDMA Systems via Admission and Flow Control
Third generation (3G) wireless systems introduce the new paradigm of ``anytime, anywhere, anytype'' wireless services.
Consequently, a variety of multimedia services are to be accommodated over wireless links.This implies coexistence of
various types of traffic with very different QoS requirements, such as different target bit error rates (BER), different
sensitivity to delay and different information rates.Using the framework provided by the cdma2000 standard proposal, we
propose an access control protocol to guarantee QoS requirements for both real time and non real time services.The
access control consists of an Admission Control and a Flow Control Algorithm.The system performance in terms of delay,
outage probability, data user throughput and total cell throughput are investigated for two types of data models: Poisson
arrivals for data packets and web traffic.Three different strategies for designing the flow control are analyzed and
compared.The impact of real time and non-real time traffic specifications on system capacity is investigated.
Paper 2.3.3.5
An OFDM Based Multicarrier MFSK System
This paper introduces a new multiple access scheme based on Multicarrier Multilevel Frequency Shift Keyeing (MC-MFSK).
This new approach alleviates some of the problems associated with the implementation of the conventional FH-MFSK
(Frequency-Hopped MFSK) system.The MC-MFSK scheme is a dual of the FH-MFSK scheme in that it transmits a symbol in
parallel over multiple sub-channels, whereas the FH-MFSK scheme does so serially.We discuss an OFDM (Orthogonal
Frequency Division Multiplexing) based design of the MC-MFSK Transceiver.We also calculate the spectral-efficiency of
the MC-MFSK system based on simulation results, and show that it is comparable to that of an FH-MFSK system.
Paper 2.3.4.1
An Iterative Approach to the Power Control Problem in Wireless Networks for Integrated
Services
This paper proposes two iterative algorithms for the uplink and downlink power control of a multi-service CDMA cellular
system.The main feature that these algorithms introduce in the process of power control is that they combine the
allocation (PA) as well as the correction of power in the system.Power Allocation is the process of allocating a certain
level of power that is close to the optimum required level, and as a result helps the power control process to approach
quickly the optimum levels.The PA part of our algorithms is concerned with the one-step power allocation so as to help
new links to enter the system and at the same time to help existing connections to maintain their QoS at a certain level.
The power correction part of our algorithms refers to the amendment of the allocated powers so as to further improve the
QoS.Both of the above tasks are carried out simultaneously acting at specific update moments of the system.The
proposed power control algorithms are decentralised in the sense that they can be implemented at the individual cell
sites and mobile stations based on local measurements and information, and without the need of co-ordination between the
different cells.Another characteristic of the proposed algorithms is that they are applicable in multi-service wireless
environments that support many different applications with different service requirements.Simulation results show that
independently of the initial power allocations our algorithms converge to the optimal values in a very small number of
iterations.Our algorithms favor the large changes on the values of powers when necessary therefore approaching the
optimal values quite fast, while thereafter the changes are very smooth in the neighborhood of the optimal values of the
powers and the corresponding SIRs.
Paper 2.3.4.2
Spatial Multi-user Access OFDM with Antenna Diversity and Power Allocation
Through the use of spatial diversity, wireless transmission system capacity can increase dramatically.However, in the
multiple-user environment, the system performance can be limited by co-channel interference.Beamforming is typically
used to suppress the interference, but it is not always able to process a multipath signal optimally, especially when the
paths from each user arrive in an alternating fashion, without losing antenna diversity.This paper describes a spatial
multi-user access scheme using singular value decomposition (MU-SVD), associated with OFDM in order to combat delay
spread.It is a spatial joint process for both transmitters and the receiver of all users without losing antenna
diversity and can outperform beamforming and space-time equalization in terms of interference cancellation and angle
resolution.MU-SVD with power allocation, which is expected to achieve a huge gain, is also being studied.
Paper 2.3.4.3
A Fast Cell Search Algorithm using Code Block CPM
in Asynchronous W-CDMA System.
Asynchronous mode W-CDMA system is known to be quite appropriate to the next generation mobile communication system,
especially in a heterogeneous cellular architecture.In this case, however, each base station needs to use different
spreading code for identification, so it is a demanding task for a mobile terminal to find the best cell site and get
an accurate code synchronization at the beginning of a communication.Since slow acquisition of a base station could
mean the failure of initiation, a fast cell search algorithm to accelerate the cell search process is essential.In this
paper, a new cell search algorithm based on the binary code position modulation within the code block is proposed.
Different cell sites are identified by different hopping code sequences, and each position modulation is performed by
the hopping code.The proposed algorithm is proved to make the cell search time in most places in a cell much shorter
than the previous algorithms, and to mak! e the receiver implementation simpler.
Paper 2.3.4.4
Weighted Fair Queueing for Data Service in a Multimedia CDMA system
In this paper, we proposed resource allocation scheme for data service in an integrated voice/data CDMA system.In this
scheme, delay-sensitive voice users are first allocated and residual resource will be allocated to data users.To
allocate data users with fair, we applied weighted fair queueing to CDMA system by considering wireless burst error
characteristics.As a result, we show that all data users under burst error channel have the same throughput.
Paper 2.3.4.5
Peak-to-Average Ratio Suppression Schemes in DFT Based OFDM
One of the most serious problems of Orthogonal Frequency Division Multiplexing (OFDM) is its high peak-to-average power
ratio (PAPR) which substantially degrades the efficiency of a power amplifier.PAPR suppression schemes for OFDM are
investigated in this paper.Coding schemes suppress the PAPR of an OFDM signal to a low level, but they cause
considerable spectral loss and do not work efficiently when the number of subcarriers is large.Phase rotation schemes
have very small spectral loss, but their suppression performance is not good.Clipping schemes suppress the PAPR
effectively, but they increase the sidelobes of the signal spectrum substantially.Amplitude limiting schemes suppress
the PAPR effectively without any spectral loss before pulse shaping, but will have an additional PAPR after pulse
shaping.However, the additional PAPR can be suppressed by using an adaptive peak suppression (APS) algorithm.Thus, a
limiter plus APS scheme is introduced for bandwidt! h efficient PAPR suppression of OFDM in this paper.It suppresses the
PAPR of 128-QPSK-OFDM from 12.7dB to 5.3dB with 1dB power loss at 0.001 symbol error rate (SER) in a white Gaussian
noise channel or 0.36dB power loss at 0.001 SER in a Rayleigh fading channel.The limiter plus APS scheme shows better
performance than the other schemes for DFT based BPSK or QPSK-OFDM when the number of sub-carrier is large (D>=32).
Paper 2.4.2.1
OPTIMAL TURBO DECODING METRIC GENERATION IN A PILOT ASSISTED COHERENT WIRELESS
COMMUNICATION SYSTEM
The exact expressions of the optimal metrics for Turbo decoding for pilot assisted coherent communication.It is shown
that for Rayleigh fading channel the optimal decoding metric, i.e., the log-likelihood ratio (LLR) of the coded bits can
be generated by forming the dot-product of the pilot-based channel estimate and the received signal sample of the coded
bits with proper scaling.It is shown that the receiver performance is rather sensetive to the scaling factor.Examples
are given to show the determination of such scaling factors for forward and reverse link receivers in a mobile
communicatoin system.Practical considerations for implementations of such receivers are discussed.
Paper 2.4.2.2
Pilot-aided Adaptive Chip Equalizer Receiver for Interference Suppression in DS-CDMA
Forward Link
In the forward link of DS-CDMA systems, employing orthogonal spreading codes and an aperiodic overlay scrambling code,
the multiuser interference is essentially caused by the multipath channel.By equalizing the channel effects, the
orthogo- nality between the different users is (partially) restored and at the same time the MUI is being suppressed.The
optimal chip equalizer receiver consists of a channel equalizer, followed by a single descrambler/despreader and a
decision device.However, adaptive implementations of the chip equalizer receiver, that can deal with fast fading
channels, are not straightforward, since no continuous training chip sequence is available.We propose a new pilot-aided
direct adaptive chip equalizer receiver, that exploits the presence of a pilot channel in forthcoming third generation
mobile cellular and satellite communication systems.Since the proposed receiver does not require explicit channel
estimation and since it is continuously updated at the symbol rate, it is well-suited for fast fading multipath channels.
An LMS or RLS symbol rate adaptation scheme has been obtained by simply reversing the order of the equalizer and the
descrambler/despreader for the updating part.Simulation results show that the proposed receiver outperforms the
conventional RAKE receiver, especially for heavily loaded systems.
Paper 2.4.2.3
Effects of adaptive equalization on the performance
of broadband wireless communications in fading channels.
Abstract: In this paper, we examine the effects of equalization techniques on the performance of broadband wireless
communications with CQPSK modulation.Although general in nature, this study is carried out in the context of its
application to high data rate wideband transmission at millimeter-wave frequencies.The performance results are based on
Monte-Carlo simulations with two power delay profile models: a one sided exponential model and a uniform model.
Simulations results show that the relative performance of linear and non-linear equalization techniques strongly depends
on the delay profile characteristics.
Paper 2.4.2.4
Nonlinear Adaptive Blind Interference Cancellation for CDMA Systems
In this paper we present a novel nonlinear blind adaptive interference cancellation (NL-BIC) scheme that applies an
optimization criterion which is using higher order statistics of the received baseband signal.The receiver may be viewed
as a blind equivalent to the centralized nonlinear successive interference cancellation (SIC) scheme.The structure of the
receiver is multidimensional comprising of vertical and horizontal stages, where the number of the vertical stages is
directly related to the performance of the receiver.The number of the horizontal stages corresponds to the number of
dominant interferers.Simulation results show that the NL-BIC scheme significantly outperforms the well known linear
multiuser detectors and is exceptionally efficient for the systems with strong and highly correlated interferers.
Paper 2.4.2.5
Implementation of an Experimental 384 kb/s Radio Link For High-Speed Internet Access
Investigations into wireless communications systems for Third Generation (3G) and beyond have dealt with a wide variety
of communications techniques.OFDM is a promising technique for high-speed wireless packet data communications in the
dispersive multipath RF channel.While idealized, computer simulations of such systems can provide valuable insight into
their operation, many impairments and system behaviors can only be studied effectively with a realistic, real-time
implementation.This paper describes one such experimental implementation of a radio link proposed for use as the
downlink for high-speed (384 kb/s and beyond) Internet access.
Paper 2.4.3.1
A Decoding Algorithm for I-Q Space-Time Coded Systems in Fading Environments.
Space-time (ST) cods have attracted the researchers because of their high transmission rate.Also, I-Q trellis codes are
known to have high coding gain in rapid fading channels.In this paper, the decoding problem of I-Q ST codes is
formulated and a suboptimal decoding algorithm is proposed to solve the problem.It is shown that the proposed algorithm
does not need additional computations and provides good performance.Results for I-Q ST codes using QPSK signal
constellation are presented.It is shown that the proposed algorithm provides gains up to 3 dB over conventional QPSK ST
codes designed in the literature.
Paper 2.4.3.2
Efficient Evaluation of Error Probabilities for Systems with Intersymbol Interference
an Gaussian Noise
A novel computationally efficient and very accurate method for the calculation of error probabilities in systems with
intersymbol interference an Gaussian noise is presented.We use an exponential expression in order to upper bound the
complementary probability distribution of the Gaussian noise component.This enables us to find a true and an approximate
upper bound for the probability of error by evaluating exponential moments of the intersymbol interference.The described
method is very accurate.In numerous examples, the relative errors between the true probability of error and the
approximations did not exceed 0.1% for systems with an open eye and 10% when the eye was closed.Additionally, the method
is very effective and easy to use, outperforming most published methods in both the number of computations required and
simplicity.
Paper 2.4.3.3
Low-Complexity Channel Estimation for WCDMA Random Access
This paper investigates various low-complexity channel estimation techniques that can be employed for the random access
channel of third-generation wideband CDMA (3G WCDMA) specified by 3GPP for IMT-2000/UMTS.The quality of channel
estimates is important for adjustments of tap weights of RAKE receivers in base stations.Schemes using slot-based as
well as symbol-based pilot-assisted channel estimates applying different kind of interpolation methods and post-filters
for interference and noise suppression are considered.Results of link level simulations for typical indoor and vehicular
fading channels are discussed and compared with the respective performance in case of ideal (undistorted) channel
weights.Analysis criterion is the frame error rate (FER) vs.average signal-to-noise-ratio E_b/N_0.It turns out that
symbol-based channel estimation can lead to significant improvements of 1-10dB compared to conventional approaches
without post-filter, especially for high speed scenarios (> 200km/h).A good choice for all random access deployment
scenarios is a non-causal forward-backward-multiplication-method (FBMM) filter employing modified polar interpolation.
Paper 2.4.3.4
Proposal of OFDM System with Data Repetition
This paper proposes a novel method for Orthogonal Frequency Division Multiplexing (OFDM) systems, which can keep the
user*fs objective performance even under very low signal-to-noise power ratio (SNR) and severe frequency selective
fading conditions, at the cost of a reduction in the information transmission speed.A salient feature of the proposed
method is that the demodulation with the coherent summation of the repeated data can be realized by down sampling on
received signal of which sampling interval is unsatisfied with the Sapling Theorem.In other words, the ratio of down
sampling is selected purposely at the receiver with larger than the sampling interval determined by the Sampling Theorem
where the repeated sub-carriers data in the frequency domain would fold coherently over the number of data repetition.
Paper 2.4.3.5
Stationary Schemes for Optimal Transmission over Fading Channels with Delay Constraint
We consider a block flat fading channel, where both the transmitter and receiver have perfect knowledge of the channel
gain of the current block, but have no knowledge of future blocks.We derive a stationary power control strategy by which
the transmitter can increase the outage capacity, given a time-window for processing.The new scheme is obtained by
casting the problem as an average reward problem, and solving it using dynamic programming.Significant SNR gains are
obtained using the new scheme.
Paper 2.4.4.1
A Blind Diversity Reception Based on Eigenfilter Approach for Mobile Communications
Diversity systems are very effective for greatly improving signal transmission performance in mobile radio
communications.Digital signal processing is now rapidly advancing and various techniques are available for radio signal
processing.This paper proposes a blind diversity reception utilizing the eigenfilter and describes its principle and
performance.Blind algorithms for the diversity based on the cyclostationarity have been discussed, and it proves that
the second order statistics are sufficient for adaptation of the diversity control.Those proposed methods were too
complicated to apply in the real-time digital signal processing systems in mobile communications.More simplified
algorithm is necessary for actual applications.This paper first derives a blind algorithm by considering the reception
diversity as one of the cyclostationarity problems.The derivation shows that the problem to maximize signal-to-noise
ratio under a constraint condition becomes the one to solve the eigenfilter (eigenvector).Power Method is employed to
evaluate the eigenvalue.Computer simulations show the characteristics of error convergence of eigenfilter in both
static and fading mobile radio environments, and average bit error rate performance.The simulation demonstrates that
the proposed blind diversity system is effective in the relatively fast fading environment such as fD less than 0.001.
Paper 2.4.4.2
C/I Balancing under limited power dynamics for JD-CDMA
The ever increasing demand for the mobile phone system has led to the development of various multiple access techniques
in order to obtain a large spectral efficiency.But spectral efficiency can only be quantified if the prescribed Quality
of Service (QoS) is met for the optimum reception of the information signal for a given bit error rate (BER).The QoS
criterion is governed by the carrier-to-interference (C/I) power at the mobile station (MS) for the downlink and at the
base station (BS) for the uplink.The power distribution at the BS or MS is based on the C/I required.It is proposed in
the literature [1] that centralized power control (CPC) at the BS would give the best power distribution for each MS to
reduce the co-channel interference, at the same time optimising the resource to improve the traffic capacity.The power
distribution so obtained by CPC is under the assumption of infinite power switching [2] which is not feasible in
practice.Moreover, FCC has ! an upper power limit of 200 W at the BS for the downlink and at higher power levels, the
dynamic switching capacity of the non-linear amplifier reduces.Hence, it is mandatory to obtain CPC under limited power
dynamics for the methodology to be adopted for implementation.In this paper, the downlink of Joint Detection-Code
Division Multiple Access (JD-CDMA), a 3G digital mobile communications system, is investigated with the CPC under
limited power dynamics of 20 dB (maximum to minimum ratio of power) as set by the service providers.Chiefly, two
algorithms have been presented in the paper to obtain C/I under limited power, classified as Hard Decision and Soft
Decision.A comparison of the two is also brought out to choose the best algorithm.The effect of different power ranges
of 30 dB and 40 dB is also investigated.Limiting of power causes the degradation in the performance as compared to the
one obtained under the assumption of unlimited power switching.Hence, any techn! ique to improve the performance under
the limited power constraint would be welcome.Following this, in this paper, a new technique of deletion of service to
the bad mobiles (DSBM) which are the major source of interference for the other MSs and require much more resource than
normal, is developed.
Paper 2.4.4.3
WCDMA Initial Cell Search
In WCDMA the cells are separated by different scrambling codes which means that the network can operate asynchronous.In
order to reduce the cell search time a three-step algorithm is given in the 3GPP specification.In the current work we
analyze the cell search algorithm analytically using flow-graph techiques.Furthermore, the analysis is extended to
cover the case of initial cell search, i.e.where the mobile station has no prior knowledge on where in the frequency
band WCDMA carriers can be found.The introduction of this extra dimension - frequency - in the cell search algorithm
obviously increases the search time.In this work, the search time is calculated for different lengths of the frequency
search list.
Paper 2.4.4.4
Adaptive QAM Modulations with Complex Spreading for High-speed Mobile Multimedia
Communications
An adaptive transmission scheme based on Quadrature Amplitude Modulation (QAM) schemes with complex spreading is
considered.The level of QAM is varied according to channel conditions.For the present study, the receiver measures the
received signal strength and an appropriate level of QAM is then determined for the next transmission.Each simulation
run has used 50,000 symbols under frequency nonselective fading channel.The results show that the spreading gain is
negligible.However, the average number of bits per symbol obtained is higher than 5 bits per symbol for all simulation
scenarios.Therefore, it is clear that the proposed adaptive transmission scheme provides very high throughput.
Paper 2.4.4.5
Selection or the Most Efficient Shrtened Reed Solomon Codes from a Neural Network
Database
We have already reported our result of designing an artificial neural network (NN) from which one can select the most
efficient unmodified RS code for a specific application.In this paper we report the continuation of our work, in
development of an artificial NN database for selection of shortened Reed-Solomon codes for a given application.To
simplify the NN design, RS codes constructed over GF(256) are considered exclusively.For software simulation of the NN a
student version of the MATLAB Neural Networks Toolbox is used.Shortened RS codes with code rate better than 0.5 are
considered exclusively.The resultant NN has five inputs, nine units in the hidden layer, and two units in the output
layer.The available inputs for this network are '%s' (the shortening percentage), 't', 'b1' (single burst error
correcting capability), 'b2' (double burst error correcting capability), and 'b3' (triple burst error correcting
capability).The outputs are the shortened n and k.The Levenberg-Marquardt learning algorithm is used to train the NN.
The NN was trained for 1500 epochs and ended with a sum squared error of 1.11594 x 10-3.The test data results show the
accuracy of selecting the correct code length and code dimension are 99.36% and 84.4% for unmodified and shortened codes,
respectively.It is shown that in cases that the NN does not come up with the most efficient code, it provides the second
best code.It is also demonstrated that the lack 100% success of selection of the optimum RS code is due to two factors;
the limitations of data used for training by the Neural Network Toolbox of MATLAB, and the fact that for certain RS codes
the burst error correcting capability is not increased by adding an extra redundant symbol.
Paper 2.5.2.1
Joint Maximum Likelihood Approach in Overloaded Array Processing
We demonstrate that, a non-linear maximum-likelihood detector that employs an enumeration technique, can jointly
demodulate multiple synchronous co-channel users impinging on an antenna array, where the number of co-channel
interferers exceeds the number of antenna array elements.
Paper 2.5.2.2
Reduced Complexity of Multi-Code DS-CDMA Receiver using a COF Only for a Pilot Channel
In this study, we propose a multi-code DS-CDMA receiver with reduced complexity.The proposed receiver uses a code
orthogonalizing filter (COF) only for the pilot channel.We compare the bit error rate (BER) performance of the proposed
receiver with that of the receiver with COFs for all channels by computer simulations.The results show the proposed
model achieves less complexity without serious performance degradation.
Paper 2.5.2.3
Signal space whitening MLSE with multibeam adaptive array
Recently, sophisticated array processing MLSE, and simplified cascaded connection of an adaptive array and MLSE have
been proposed.In this paper, the difference between them is analytically discussed.In addition, we propose novel
schemes of time-space signal processing derived from the both types.Computer simulations show that signal space
whitening (SSW) MLSE, which is one of the proposed schemes, reveals better BER performance, and has less complexity
compared to the array processing MLSE.
Paper 2.5.2.4
Turbo MAP Decoder Design for IS-2000 system
In the IMT-2000 specifications, turbo code can be used for one of the channel coding methods.Especially in the data
transmission requiring high data rates, this scheme can be adopted.In this paper we design a Turbo MAP decoder for
IS-2000 which is one of the IMT-2000 specifications.Design parameters and structures are generated by various
simulation results.Modified window framing method is adopted and Log-MAP algorithm is replaced with MAX Log-MAP
algorithm.This hardware can decode for every data rates specified in IS-2000.
Paper 2.5.2.5
Joint Decoding and Channel Estimation for Space-Time Codes
Space-time codes acheive high data rates by jointly coding over multiple transmit antennas.In the design of such codes
it is usually assumed that perfect channel knowledge is available at the receiver.In practice, performance depends upon
the quality of the channel estimates available.Our contribution is a low complexity joint decoder/channel estimator for
space-time codes.We shall briefly describe the channel and the principle of the receiver.We shall present simulation
results which show that the receiver can approach the performance of the optmial decoder with perfect channel knowledge.
Paper 2.5.3.1
Antenna Diversity Combining Schemes for W-CDMA in Fading Multipath Channels
In this paper and the accompanying talk, we consider the effects of correlated fading on the performance of W-CDMA
systems using transmit diversity.We also investigate the use of two receive antennas in addition to two transmit
antennas and quantify the gains that can be achieved.Having two antennas at both the transmitter and the receiver makes
it possible to employ several diversity and dual channel transmission schemes.We study some of these schemes
analytically as well as through simulations in various fading multipath channels.
Paper 2.5.3.2
Interference cancellation using the Gibbs sampler
This paper introduces a new method of interference cancellation for the base station in a CDMA system that is based on
the Gibbs sampler which performs within 1 dB of the single user bound.The performance of the Gibbs sampler is compared
to the performance of a three-stage partial parallel interference canceller and is shown to have a gain of 0.6 dB at a
raw BER of 10% and a gain of 2.8 dB at a raw BER of 1%.This will result in significant capacity gains of 15% and 90%,
respectively.
Paper 2.5.3.3
Accurate Noise Estimates in Multicarrier Systems
This paper applies two methods to acquire accurate noise estimates for the purpose of optimizing a multicarrier
transmission system.The first method applies the EM (Expectation Maximization) algorithm to an OFDM system in order to
find the noise power present in each subchannel.The algorithm is shown to have a simple recursive formula with
relatively low complexity.The second noise estimation method operates in decision directed mode.In decision directed
mode, the noise estimates are acquired instantaneously from the received data.It is not the variance of the decision
directed noise, but that of the original noise that is desired for purposes of loading.The decision directed noise
samples cease to have a Gaussian probability density function (pdf), even though the original noise has been assumed to
have a Gaussian pdf.The exact probability density function of the decision directed noise is derived for the
multicarrier system.From this pdf, a closed form expression for the variance, in terms of the original noise variance,
is computed.The variance of the noise in decision directed mode is an under-estimator of the true variance.Such
decision directed estimate could lead to an optimistic SNR that requires to transmit on tones that have low SNR,
leading to overall performance degradation.To ease implementation, the decision directed variance expression can be
stored in a lookup table to acquire the true noise variance.Once the true noise variance has been found by either of the
above methods, then appropriate loading can be done on the subchannels.
Paper 2.5.3.4
An Improved Decision Feedback Receiver for CDMA IS-95 Reverse Link
In this paper, an improved decision feedback receiver is presented for the CDMA IS-95 reverse link.Two techniques are
proposed to improve the receiver performance.One is the noncoherent block detection taht uses multiple Walsh codes for
joint detection, and the other is the iterative decision feedback detection.Compared to its counterpart decision
feedback receiver, a significant performance improvement is oberved via the computer simulation for both AWGN and
Rayleigh flat fading channels.
Paper 2.5.3.5
On the Effect of Correlation in Multislot Link Layer Analysis for GPRS
Previous studies on the performance of the GPRS link layer have been based on a singleslot per frame allocation.A major
feature of GPRS is the ability to allocate multiple slots per frame to specific users.Under such circumstances there can
be significant correlation between the channel quality on adjacent slots and therefore it is necessary to build in an
allowance for this correlation in performance estimation.This paper considers the influence of intra-frame correlation
on the GSM-GPRS link layer when multiple slots per frame are allocated to a single user.The paper examines different
operating environments and considers the impact of frequency hopping and slot allocation policy on link quality measures
for a multiple slot MS class.
Paper 2.5.4.1
A block coded modulation method for variable-rate data transmission
We describe a block coded modulation method to produce a variable data-transmission rate using a one-sided link.This
method uses signal points that are added to the normal signal constellation of the digital modulation, e.g., QPSK,
16QAM.The different numbers of the bits are assigned to the added points.This is the basis for changing the
transmission rate.However, the Euclidean distance becomes quite short and the bit error rate performance is severely
degraded.To avoid this, a multi-level block code is constructed using these signal points.The signal points are
set-partitioned.We can lengthen the Euclidean distance of the code with this modified signal constellation.To
demodulate the signal we use the Viterbi algorism of the block coded modulation for maximum likelihood decoding.The
trellis diagram used for the Viterbi algorism is the same as that of trellis coded modulation.We obtained both a large
coding gain and variable-rate data transmission by using this method.We evaluated the method by using computer
simulation.
Paper 2.5.4.2
Modeling Interference Diversity in GSM Networks
The benefits of Frequency Hopping in GSM are frequency and interference diversity and result in better transmission
quality.Frequency diversity can easily be modeled in link level simulations, whereas the simulation of interference
diversity is more advanced, because different signal to interference ratios within one codeword have to be taken into
account.In this paper the effects of interference diversity on the error probability are theoretically analyzed and a
simple simulation model is derived.
Paper 2.5.4.3
Adaptive Acquisition for DS-SS Systems with Antenna Diversity
We propose an adaptive code acquisition scheme that adjusts the degree of diversity combining without explicite
knowledge of the SIR.This adaptive method performs like the acquisition with full diversity combining for low SIR, and
it acts like the scheme without combining (parallel search) for high SIR.Therefore, it should be useful for practical
CDMA systems for which the SIR is unknown.
Paper 2.5.4.4
Space-Time Bit-Interleaved Coded Modulation with an Iterative Decoding Strategy
A space-time coding scheme for spectral efficient wireless communications deploying multiple transmit and multiple
receive antennas is presented.The scheme is based on the concatenation of a convolutional encoder, a bit interleaver,
and a space-time signal constellation mapper that combines multi-level/phase modulation with multiple transmit antennas.
The decoding strategy follows an iterative (turbo-like) approach, where soft information is exchanged between a soft-in
soft-out demapper and a soft-in soft-out convolutional decoder.Performing some iterations improves considerably the
bit/frame error rate performance.This decoding strategy is applicable with one or more receive antennas, and shows that
reliable communications are possible with a limited decoding complexity.Simulation results in a flat Rayleigh fading
channel are reported for a scheme with a spectral efficiency of 2 bits/s/Hz, deploying two or more transmit antennas
and one or more receive antennas.It is shown that significant performance improvements can be achieved over known
space-time coding schemes depending upon the Doppler spread conditions.
Paper 2.5.4.5
UEP of Progressive Images in Wireless Channels
We present a general optimization method of progessive UEP schemes for embedded image sources in wireless communication
channels.A 2-state G-E model is exploited to approximate physical fading channels in wireless communications, in which
each state corresponds to a binary symmetric channel (BSC).Under the assumption that exact knowledge of channel state
information (CSI) is not available, the allocation of source/channel rate for unequal error protection (UEP) schemes is
optimized by using the statistics of the G-E models and maximization of the expected error-free source bit stream length.
An performance upper bound is also given for such UEP schemes in G-E channels.Simulation results show about 0.3 dB PSNR
improvements over the conventional method at the price of negligible overheads.It is also demonstrated that usually
2-rate dynamic UEP schemes are enough to get almost all the UEP gains.
Paper 2.6.2.1
Power Control in a Multicell CDMA Data System Using Pricing
Communication systems that support wireless transmission of data are becoming increasingly popular.One important issue
regarding the efficiency of data transmission is effective power control.To explore this issue, we use the concepts and
mathematics of game theory in microeconomics.In this context, the quality of service (QoS) of a wireless terminal is
referred to as the utility (measured as successful number of information bits transmitted per unit of battery energy
(bits/Joule)) and distributed power control is a non-cooperative power control game where users maximize their utility.
The outcome of the game is referred to as a Nash equilibrium.We consider a multicell wireless CDMA data system.We first
introduce the multicell power control game (MCPG) where each user maximizes its utility over its own transmit power and
over all the base stations.We show that the distributed power control solution offered by MCPG results in inefficient
power usage.We examine a linear pricing scheme to improve the Nash equilibrium result of MCPG.In the multicell power
control game with pricing (MCPGP), each user maximizes its net utility (utility - price).We show the existence of Nash
equilibria in MCPGP.We present a distributed power control algorithm that converges at a Nash equilibrium.We provide
and evaluate two heuristic techniques where each base station calculates a pricing parameter using local traffic
information that lead to improvement in utilities of all the users in the system.Our numerical results show there is
considerable gain in utilities with both techniques compared to the power control game with no pricing.The gains
achieved by pricing are higher in systems that are more congested.Also, for a particular choice of the pricing factors,
the terminals in cells with highest load tend to have higher gains than terminals in other cells.
Paper 2.6.2.2
Performance of Link Adaptation in GPRS Network Simulations
GPRS has become a key step for applications that require wireless data communication.In GPRS four coding schemes have
been defined to protect the information.This work tries to compare the performance of the four coding schemes with link
adaptation for different frecuency reuse configurations, analyzing the different power control strategies, and based on a
traffic model according to switched data services.
Paper 2.6.2.3
Performance of Coded Higher Order Modulation Schemes and Hybrid ARQ for Next
Generation Cellular Systems
One of the key requirements for Fourth Generation (4G) CDMA systems is to provide a very high bit rate packet data
services (e.g.peak rate in excess of 5 Mbps)for both low and high mobility applications.One way to achieve higher peak
data rate is to use spectrally efficient modulation schemes (M-QAM where M>4) instead of the current QPSK modulation.
Further, in order to support higher peak and average data rates the capacity of the current system should be enhanced by
means like transmit and receive diversity, hybrid ARQ, powerful channel coding like Turbo codes, adaptive modulation and
coding schemes, etc.In this paper, the simulated performance of coded 16 QAM and 64 QAM modulation are presented for
various Turbo Code rates under fading channel using both ideal and non-ideal channel estimation.The effect of Space Time
Transmit Diversity (STTD) and Hybrid ARQ on the link performance for M-ary QAM are also simulated and compared with the
standard 4-QAM scheme.The performance metric used for comparison across the various coding and modulation schemes is
based on the average link throughput measured in kilobits per second.
Paper 2.6.2.4
Equalization and multi-user detection in frequency selective channels for Space time
block coding based transmit diversity (STTD)
The third generation partnership project (3Gpp) for WCDMA FDD system has chosen space time block coding based transmit
diversity (STTD) as the open loop transmit diversity technique for broadcast and dedicated channels for the base station
to the mobile (forward) link transmission.On the other hand, the 3Gpp WCDMA TDD system has chosen STTD as the open loop
transmit diversity technique for only the broadcast channels of the TDD forward link.The WCDMA receiver structure for
the TDD mode is quite different from the FDD system due to the presence of the equalizer for multi-user detection and
intersymbol interference (ISI) rejection at the mobile.Thus the STTD receiver at the mobile for the WCDMA TDD mode has
to do equalization and multi-user detection in addition to STTD decoding.In this paper we derive the joint zero-forcing
STTD (ZF-STTD), the joint minimum mean square error STTD (MMSE STTD) equalizer/multi-user detectors for the WCDMA TDD
systems.We show that for dual antenna transmission using STTD encoding, a ZF-STTD decoding receiver at the mobile gives
between 1.0-3.0 dB gain over single antenna transmission, depending upon the multi-path channel model.Thus STTD encoding
gives significant diversity gains over single antenna transmission for the WCDMA TDD systems.Hence STTD was accepted as
the open loop transmit diversity scheme for the broadcast channels of the 3Gpp WCDMA TDD mode.
Paper 2.6.2.5
Cutoff Rate Analysis of Pilot Assisted CDMA System With Power Control
Pilot assisted reverse link has been proposed to several third generation systems, such as CDMA2000 and WCDMA.A
systematic analysis of various aspects of a pilot assisted CDMA communication system, including optimal reception,
performance bound, and cutoff rate, have been presented in [1].A QPSK modulated reverse traffic channel and a binary
modulated pilot channel are transmitted together through a fading channel.Channel estimates based on the pilot channel
signal are used to coherently demodulate the traffic data to obtain marginal gain over previously proposed method, such
as IS-95A/B system.However, what was not described in [1] is that the reverse link is usually power controlled via a
closed loop with an update rate of 800Hz [2-5].To make the theoretical analysis to be closer to a real environment of a
typical wireless communications system, in this paper, we will provide an analytical treatment of the receiver
performance by introducing the dependency of the received signal and channel estimates on power control.By taking
account of channel estimation error and power control, the results obtained are more realistic to practical situation.
Paper 2.6.3.1
Effects of Mobile speed on system performance, results from Orange/Fujitsu UMTS field
trials in UK
This paper will give an overview and discuss in brief the main results of the joint Orange/Fujitsu UMTS field trials
during last year in Bristol UK.In particular this paper will address the effects of the vehicle speed on system
performance.The outline of the paper is as follows.Section 2 describes the field trial set-up and equipment
configuration in addition to a summary of the field trial achievments and results.Section 3 will provide the
theoretical background study on the channel estimation and in particular on the technique used during the trials.Field
experiment results of the channel estimator tests under various speed conditions are presented in section 4.Conclusions
and summary are provided in section 5.
Paper 2.6.3.2
Transmission Delay Control for Single Frequency OFDM Multi-Base Stations in a Cell
using Position Information
We will introduce single frequency OFDM Multi-Base stations in a cell, where a transmission delay control by using
position information from Global Positioning System (GPS) is proposed.This system suppresses delay spread in constant
range by controlling transmission timing based on the information of mobile position given from GPS.The proposed system
will be effective for a high speed demand, because a guard-interval can be made shorter, and furthermore the diversity
gain will be obtained by receiving signals from several stations at the same time.
Paper 2.6.3.3
Measurement Assessment for Link Quality Estimation in 3G Wireless Communication
Networks
In this paper we propose a method to judge metrics for link quality estimation (LQE).Link quality control is essential
to meet the QoS requirements in terms of error rate (BER/BLER) while minimizing the consumed power on the radio link to
save resources.Because a large set of possible metrics for LQE has been proposed it is necessary to compare the proposed
methods in the beginning of the system design.We present a method to basically evaluate the performance of a metric for
estimating the link quality before specifying the control algorithms.
Paper 2.6.3.4
Data Fusion based on Neural Network for the mobile subscriber location
This paper presents a data fusion method based on neural network to localize a mobile subscriber in using the
radiolocation measurements provided by several base stations.This method allows to obtain an accuracy of 64m in 67% of
the cases.A generalization of neural network process has been realized in order to localize the mobile station in any
circumstances.
Paper 2.6.3.5
New Generation Features for Tactical Wireless Communication Networks
Mobility of forces increased range between formations and advanced electronically controlled systems call for new
technical solutions for tactical communication networks.Access to fast, secure and reliable communications is more than
ever before the key to success.Different applications services and different applications should be supported.This
paper comprises all new data features according to standardized protocols and interfaces in tactical wireless
communication networks.Also required ECCM methods are presented analytically, as the electronic warfare methods are
sophisticated and will become more in future.Finally, features for the line of sight transmission, network management,
encryption, switching, survivability, modularity interoperability and performance of the new tactical communication
systems are also discussed.
Paper 2.6.4.1
An Equal-Strength/Power-Suspended Power Control Scheme for a Cellular DS/CDMA System
The paper proposes a closed-loop equal-strength/power-suspended uplink power control scheme (denoted by PCX) for a
cellular DS/CDMA system.In the scheme, when the small-scale fading, SF(t), is less than a preset threshold, H0, MS
(mobile station) suspends transmitting signal; when SF(t)>H0, MS*s transmitting power is adapted to combat the
small-scale fading so that the received signal power level is constant.We compare the proposed PCX scheme with the
perfect average power control scheme (PCO), equal-strength power control scheme (PCE), equal-strength/power-limited
power control scheme (PCL) and equal-strength/power-limited+rate-adapted power control scheme (PCLR).The system
performance measures, including the system capacity, total transmission rate (TTR), and MS's average transmitting power
(ATP) of each power control scheme are mathematically derived.For the case of H0=1.0, we found that PCX*s TTR is 206%
of PCE's, and 141% of PCLR's.And PCX*s ATP is 33% o! f PCE's, 56% of PCLR's, and even 66% of PCO's.Therefore, we
conclude that the PCX scheme can achieve the highest total transmission rate and the lowest user's power consumption.
Paper 2.6.4.2
Outage Performance Considerations in Cellular Systems: A Comparative Review
This paper is a comparative overview of the existing well-known techniques for the calculation of the outage probability
in several mobile radio environments (Lognormal, Rice, Nakagami).The comparison was made using a newly generalized
approach as a reference point, for the direct evaluation of the outage probability in the presence of L mutually
independent co-channel interferers.This approach can be used to evaluate the outage performance with high accuracy,
speed and arbitrary values for the modeling parameters in both cases of interference limited (no minimum power
constraint) and existence of a minimum power constraint.Computer results are also presented and discussed to show the
differences between the compared methods.
Paper 2.6.4.3
Quality of Service Management for Mixed Services in WCDMA
The WCDMA solution for IMT-2000 has an in-built service flexibility that will provide wireless access for a mix of
simultaneous services, each with different quality requirements, while achieving high spectrum efficiency.This paper
evaluates different admission control policies in a mixed services WCDMA system, by means of multi-cell radio network
simulations.A first scenario includes one conversational speech service and one web browsing service using the
interactive class.This is then extended to two kinds of interactive services with different priorities.The performance
of different algorithms is studied in terms of quality, capacity and system throughput.
Paper 2.6.4.4
Joint Power Control, Base Station Assignment and Sectorization for CDMA cellular
Systems
A CDMA cellular scheme that dynamically adapts the cells to the spatial load distribution is proposed.The scheme
maximizes the network capacity for a given number of base stations, for any distribution of the mobile users.It combines
power control, base station assignment and adaptive sectorization efficiently, and can be easily integrated into the
already deployed CDMA systems.Simulation results show that our relatively low complexity approach, achieves a
performance quite close to that of an optimal beamforming scheme under uniform and non-uniform load scenarios.
Paper 2.6.4.5
Design of Cyclically Permutable Codes for PN Code Acquisition in WCDMA TDD Mode
The WCDMA system proposed by 3GPP to ITU uses different scrambling codes for different base stations.Thus, the PN code
acquistion problem consits of not only determining the timing but also the identity of the scrambling codes.Cyclically
permutable (CP) codes were proposed for the 3GPP WCDMA FDD mode to facilitate fast PN acquisition.However, these codes
are not optimum for the WCDMA TDD mode and have to be redesigned.In this paper, we design optimum CP codes for the TDD
mode.The new codes are linear combinations of QPSK modulated orthogonal signals.The signal set and the modulation
identify the timing phase and the code group of the scrambling codes.These codes also allow GSM to TDD handover and have
improved performance over the FDD codes adapted for WCDMA TDD mode.The new codes have been accepted and are a component
of the 3GPP WCDMA TDD mode.
Paper 2.7.2.1
Effect of Phase Noise on RF Communication Signals
In this paper, we introduce, as a new parameter, the phase-lock loop (PLL) bandwidth of local oscillators normalized to
the symbol rate in order to generalize the phase noise effect.Using this parameter, we estimate the phase noise
effect on the bit error rates (BER) and error vector magnitude (EVM) of the band-limited channels.We also discuss the
effect on the adjacent channel signal based on the same simulation.The results are useful for the design of mobile
terminals, especially multi-mode terminals like the software-defined radio.
Paper 2.7.2.2
Forward Link Capacity based on Interference Characteristics in CDMA systems
In this paper, we introduce location-dependent forward link reuse factor, defined as the ratio of the same cell
interference to other cell interference, and provide more accurate analysis on the interference characteristics under
the multi-path environments.With the modeling and analysis on interference mean power level and its characteristics,
the analysis of forward link capacity considering interference determined according to mobiles distribution is
provided.The required Eb/It to guarantee the same BER (bit error rate) at each point can be suggested through analysis
and simulations.The forward link capacity of IMT-2000 system can be obtained with the target Eb/It and the hand off
gain.From this work, it is shown that the interference characteristics as well as the total interference power needs
to be considered in determining the required signal power.In addition, the effect of the outer loop power control is
addressed on the capacity and the interference! to other cells.Simulations will be carried on by comparing the system
performances: one without outer loop power control with target Eb/It to its highest and the other with ideal outer loop
power control with its location-dependent target values.Generalization of this approach to CDMA systems with multiple
class service can also be addressed.
Paper 2.7.2.3
Traffic Modeling and Performance Analysis for Dual-Band Systems
This paper proposes an analytical method for system performance analysis of a wireless system operating on two bands.
The system performance in terms of average call blocking rate is investigated in this study and it is shown that the
proposed analytical tool has a good match to the actual call blocking rate when the average call blocking rate is less
than 10%.Equations developed in this paper can be easily incorporated into Microsoft Excel spreadsheet as Macro
functions, thus traffic performance engineer can quickly and more actually design a dual-band system with minimum voice
path configuration that meets the minimum average call blocking rate requirement.
Paper 2.7.2.4
Performance of Optimum Transmitter Power Control in WCDMA Cellular Mobile Systems
In this paper, we consider to combine the MAC protocol and physical layer design to propose the scheme of designing
power control sub-channel for WCDMA multimedia mobile systems.The aim is to make the power control for WCDMA mobile
systems is more effective.We also analysis the power control problem in WCDMA mobile systems and propose the optimum
power control theory of optimization of multi-thresholds based on ranking the priority orders of multimedia services.
Simulation results show that the proposed algirithms can provide better performance for WCDMA mobile systems.
Paper 2.7.2.5
Mobile Location Method for Non-Line-of-Sight Situation
Mobile location technology is becoming an important topic for the purpose of satisfying the US FCC E-911 location
requirement and for driving Location Commercial Services in Europe.The typical method for positioning a mobile is based
on using trilateration and triangulation techniques, which require time of arrival (TOA) and Angle of arrival (AOA)
information, respectively.A recent study shows that network-assisted GPS solution has a good location accuracy
regardless of the cost and complexity.However, GPS technology is developed for a line-of-sight(LOS) propagation
environment.In the high-rise urban area, the majority of the rays propagating from the satellites to the receiving
mobile are non-LOS.This situation has been expected to increase the error of GPS location estimation.In this paper, we
describe a method to correct GPS location estimation error due to the non-LOS situation.Since the non-LOS rays
transmitted from satellites to the mobile station are blocked by the buildings surrounded by the mobile, these blocked
rays introduce the range residue which is defined as a set of ray path differences between the non-LOS and LOS time of
arrival.The range residue can be identified through a simple ray-launch calculation and the range residue can be used
to calibrate location error between GPS predicted location and the true caller's location.When an emergency caller
location is required, the calculation result from range residue can direct GPS predicted location to the true caller's
location.In this paper, we will use the developed method to systematically analyze the location error caused by
average building height and street width.We will also consider other issues related to location error, such as the
number of satellites used and their geometrical arrangement.
Paper 2.7.3.1
A new hybrid MAP/MLSE soft-output adaptive equalizer for TDMA-based land mobile
cellular links
A novel adaptive receiver for TDMA-based cellular land-mobile radio communications that merges the advantages of both
SbS-MAP and MLSE receivers is proposed.More in detail, the proposed equalizer feeds both a Kalman-like non-linear
channel estimator and an MLS equalizer with the soft-information given by the A Posteriori Probabilities (APPs) of the
state sequence of the ISI channel.In the proposed receiver, the APPs only are used for channel estimation and
equalization (as the branch metrics used in the Viterbi Algorithm (VA)).The exploitation of the advantages of these two
equalization techniques in a combined form yields to an adaptive receiver that outperforms other adaptive receivers that
rely either on SbS-MAP or MLSE detectors only.Moreover, the channel estimator embedded in the proposed adaptive receiver
is able to exploit the knowledge of the power-delay profile of the link and, therefore, enhance its tracking capability.
Paper 2.7.3.2
On the achievable network capacity of the cdma2000-1X system with and without transmit
Diversity
As CDMA networks evolve from IS95 to IS2000, network capacity should increase.The increase is attributed to fast forward
power control and transmit diversity.This paper compares the achievable forward link capacity of IS95 and IS2000 for
9600bps voice traffic.Three transmit diversity schemes are considered, Phase Sweeping Transmit Diversity (PSTD),
Orthogonal Transmit Diversity (OTD) and Space Time Transmit Diversity (STTD).In addition, both IS2000 Radio
Configuration 3 and 4 are studied.Performance results are analyzed using the IMT-2000 Vehicular and Pedestrian channel
models.The results indicate that a IS-2000 system operating with Radio Configuration 4 and Space Time Spreading provide
the greatest capacity gain over IS95.Radio Configuration 3 reduces per user traffic channel power requirements due to
the lower rate convolutional code.However, due to Walsh code exhaustion, improved Erlang capacity with RC3 over RC4 is
not expected at network blocking levels of 1%.
Paper 2.7.3.3
CDMA Capacity on Pathloss and Power Control
A high capacity digital system based on the Direct Sequence Code Division Multiple Access (DSCDMA) is being developed and
will be commercially available soon.CDMA system provides several different features to improve the system capacity and
is generally viewed by engineers as the solution for the capacity problem that the analog system is facing right now.In
this paper, we evaluate both the pathloss as well as stepping of power control impact on the CDMA capacity.First,
different path loss exponents vary from 2 to 4 is used for the simulation and corresponding interference ratios are
calculated for all cells involved in the simulation to study the impact of path loss exponents on capacity.Second,
different power stepping sizes are applied to the simulators.
Again, the corresponding interference ratios and the GDMA interference (rise over NoW) are calculated to study the
impact on the CDMA system because of the power control stepping.A power control stepping effect model is developed and
compared with simulation with power control on flat terrain with flat fading and uniformly distributed mobiles.The
capacity is analyzed based on a set of predefined values of forward and reverse links system parameters
Paper 2.7.3.4
Handoff Rerouting Scheme for Multimedia Connections in ATM-based Mobile Networks
Next generation wireless systems promise seamless international roaming and personalized, multimedia-based network
connections.An important challenge to meeting this goal is the support of wireless multimedia connections, especially
connections where multiple endpoints are roaming.In this paper, we introduce a handoff rerouting scheme that supports
multimedia traffic over mobile-mobile connections.We describe the signaling and routing procedures of the new scheme.
Then we discuss related mobile-mobile rerouting techniques.We analyze and compare the performance of all of the schemes
under a common framework.The results show a superior performance for the new scheme in route efficiency and bandwidth
consumption for all traffic types, and a smaller handoff delay for delay sensitive traffic.
Paper 2.7.3.5
Combinations of Power Controls for cdma2000 Wireless Communications Systems
Power control in cdma2000 consists of a reverse link closed loop power control (RCLPC), a reverse link outer loop power
control (ROLPC), a forward link closed loop power control (FCLPC), a forward link outer loop power control (FOLPC), and
an open loop power control (OLPC.In this paper, all these power control algorithms are interconnected and investigated
for a cdma2000 system.In addition, bit error rate (BER) results of both reverse and forward links are observed.The BER
results of the interconnected power control algorithms and their combinations have not been reported yet to the authors*
knowledge.The BER results in our paper will show how each power control algorithm affects performance of the overall
system and other power control algorithms.
Paper 2.7.4.1
Power Control with Time Delay Compensation
Time delays reduce the performance of any controlled system.If neglected in the design phase of a power control
algorithm, a more oscillative or even unstable behavior may be observed when using the designed controller in the actual
system.To overcome these problems, Time Delay Compensation (TDC) is introduced.The main idea is to adjust the
measurements (\eg SIR) to include the effect of issued, but not yet applied, power control commands.As such TDC provide
more stable operation, which in turn enables capacity utilization more efficiently.This conclusion is supported by
illuminating simulations.Moreover, discrete-time describing functions are used to describe the dynamics of step-wise
power control.The analysis predict several possible modes of oscillation, which is supported by simulations.
Paper 2.7.4.2
Mobile Communications beyond Third Generation
This paper describes a vision for mobile communications beyond third generation based on a flexible platform of
available, evolving and emerging access technologies including new concepts as sef organizing and optimizing radio
access systems.
Paper 2.7.4.3
INVESTIGATION OF 3RD GENERATION MOBILE COMMUNICATION RACH TRANSMISSION
In this paper, we investigate the random access channel (RACH ) transmission in the 3rd generation mobile communication
based on the specification developed within 3rd Generation Partnership Project (3GPP).Because there are different kinds
of messages with different QoS requirements, we propose a new preamble transmission strategy to guarantee the average
transmission delay for each access service class on RACH.The influence of several parameters is discussed.Besides, an
algorithm to enhance the throughput and delay performance is proposed.
Paper 2.7.4.4
A Markov-Based Model for Performance Evaluation in Multimedia CDMA Wireless
Transmission
In this work we investigate the behavior of block errors in multimedia DS-CDMA transmission systems operating over slow
fading channels.We find that block errors can be accurately modeled by a first-order Markov process.Although Markov
models have been used before to analyze packet transmission over radio channels [2]-[5], they have not been applied to
CDMA systems that incorporate convolutional codes (CC) with soft-decision decoding.A major contribution of this work is
to include in the new Markov model the effects of the CC, soft-decision decoding, and the RAKE diversity fingers with
maximal ratio combining.A method to estimate the Markov process parameters is presented.Another major contribution of
this paper is the analysis of the throughput of the Go-Back-N and selective-repeat automatic repeat request (ARQ)
protocols over DS-CDMA systems using the proposed Markov model.Several cases involving different numbers of RAKE fingers
and various values of round trip delays are analyzed.Our approximation is found to be excellent in all cases.The study
of multimedia transmission over DS-CDMA channels is greatly simplified using the model introduced in this work.
Paper 2.7.4.5
Scheduling Strategies for Downlink Packet Transmission in W-CDMA UMTS
The downlink packet data transmission on a shared channel in W-CDMA UMTS (FDD) is analyzed.The shared channel is useful
to multiplex several users for bursty data transmission such as Internet access in the downlink direction.When several
users share a common resource, the performance in terms of delay and throughput is largely affected by the scheduling
discipline used.The performance of the shared channel is investigated for three different scheduling algorithms.
Paper 2.8.3.3
A Comparison of Array Structures for Indoor Wireless Communications based on Analysis
and Simulation of Channel Capacity
Recent research has demonstrated that the capacity of a multipath-rich channel (such as indoors) is dramatically
increased when antenna arrays are used at both transmitter and receiver.This is acheived by using the multipath to
create parallel subchannels.This ability to transmit parallel data substreams (and therefore the total capacity of the
channel) is determined by the angular separation of multipath and the structure of the antenna arrays.This paper
presents a mathematical analysis of the capacity for 2 paths, and uses the result to compare linear, circular, and
Y-shaped arrays.For comparison, similar results are generated for channels of 3 and 4 paths using computer simulations,
since only the 2-path case has an easy closed-form mathematical solution.Finally, these results are compared to
capacities of simulated channels based on a statistical model for indoor propagation.The results allow conclusions to be
made about ideal array structures for indoor communications applications.
Paper 2.8.3.4
Comparison of Indoor Propagation Channel Characteristics at 893MHz and 37.2GHz
This paper reports a preliminary results of experiments comparing two indoor radio channel measurements obtained at
893MHz and 37.2GHz.Under same scenarios, Narrowband and Wideband measurements are performed using vertically polarized
omnidirectional antennas mounted on an automatic transmitter-receiver system having a resolution data sampling of 2
samples/mm.Under line-of-sight (LOS) conditions, the distance-power law exponent is found to be lower than the free
space condition for both frequency bands with a great channeling effect on the mm wave frequency band.Large and small
scale variations extracted from the original data are shown to follow log-normal and Rayleigh/Rice distributions,
respectively.The wideband results are obtained by performing impulse responses for a transmitted pulse of 5n.The
maximum RMS delay spread for the UHF band is almost 100ns whereas it is of 60ns for the mm-waves band.
Paper 2.8.3.5
Wide Band Indoor Radio Channel Measurements at 5.8 GHz
Wide band measurement and characterisation of indoor propagation at 5.8 GHz is taking growing importance due to the
amount of systems that could be implemented in near bands, as BRAN (Broadband Radio Access Networks, formerly HiperLAN)
and last mile implementations for distribution systems of broad band services [1].In this contribution the results of
a measurement campaign of indoor radio channel at this frequency will be shown, and comparisons with ray tracing results
will be presented.Indoor measurements have been performed using a wide band radio channel sounder, based on a vector
network analyser HP8510C, in co-ordination with a high precision linear positioning system [2].Both antennas had
omnidirectional radiation patterns in azimuth.The transmitter antenna was placed in a stationary location and the
receiver was moved along 2.5 m long linear paths in several environments, taking measurements each one eighth of a
wavelength, by means of the automated positioning system.This system enhances the precision of the location, comparing
with the traditional manual system.At each position, frequency responses have been measured with a resolution of 200
KHz in a 160 MHz band around 5.8 GHz.Several environments have been considered in this measurement campaign: LOS and
NLOS large and small rooms, and corridors, and the different characteristic functions and parameters have been
obtained.Frequency responses (figure 1), as well as power delay profile, for each point of the line at each environment
will be presented.Wide band parameters as root mean square delay and coherence bandwidth (figure 2), as a function of
the position of the antennas, have been computed from the measured data [3].The figures that are showed as examples are
the results after processing the measurements done in a LOS lab environment.A complete wide band characterisation at
the considered frequency band has been achieved with the collected data.It has been also used to validate an indoor ray
tracing simulation tool.These ray tracing simulations, performed taking into account the electromagnetic properties
of building materials in the same frequency band [4,5], have been computed and their results have been compared with the
real measurements.
Paper 2.8.3.6
Performance Evaluation of Space-Time Block Coding
Multiple-element transmit and receive antennas has shown very promising results for improved bit error rate and spectral
efficiency in a rich-scattering wireless channel.Transmit diversity is interesting as a method to combat fading in
wireless channels, because of its relative simplicity of implementation and feasibility of exploiting multiple antennas
at the base station.Space-time trellis coding and Space-time block coding (STBC) have been proposed.STBC retain the
property of having a very simple maximum likelihood decoding algorithm, based only on linear processing at the receiver,
its computation complexity is similar to that of maximal- ratio receiver combining.Existing reports about STBC
performance evaluation consider mostly rich-scattering wireless channel models, with completely uncorrelated signals at
each antenna.Such situation occurs where the azimuth spread is sufficiently large.For the outdoor systems with high
base stations antennas, the angular spread may be only a few degrees.In this work, to evaluate the feasibility and
sensibility of STBC in outdoor systems applications, bit error rate evaluations are performed, by Monte- Carlo
simulations.We consider a uniform linear array at the base station, in a macro cellular and urban environment.A
stochastic spatial radio channel model is used, including additional concepts such as time delay and angle of arrival
spreads.Model's probability distributions are extracted from experimental data collected.
Paper 2.8.3.7
Combined Pilot Aided and Decision Directed Channel Estimation for the RAKE receiver.
This paper presents pilot aided decision directed approach to estimate Rayleigh fading channel in Direct Sequence Code
Division Multiple Acess (DS-CDMA) Rake receivers.Simulation results are evaluated against ideal estimates and the
estimates obtained by conventional interpolation.
Paper 2.8.3.9
Evaluation of space-time turbo-codes for third generation systems
Recently several authors including Foschini have pointed out the substantial capacities available in MIMO (Multiple In,
Multiple Out) radio channels, i.e.where arrays of multiple antennas are used at both transmitter and receiver.
Turbo-codes are well-known as being able to approach very closely the capacity of the single-in, single-out (SISO)
channel.In this paper we describe a technique for evaluating the performance of schemes based on the application of
turbo-codes to MIMO channels, in particular on alternative methods of mapping code bits to multiple antennas.We
determine the statistics of the minimum Euclidean distance at the receiver, and hence the BER achievable with given
confidence.We also consider methods for the application of these codes in third generation standards.
Paper 2.8.3.10
Spatial Domain Interference Canceler Using Multistage Adaptive Array with Precise
Timing Estimation
We have proposed a novel spatial domain interference canceler applying a multistage processing concept into the MMSE
adaptive array.Using this technique, it is expected that weak power signal can be detect in the succeeded stages after
removing another strong power signal already detected.This idea can be enhanced to the reference timing estimation
required in MMSE algorithm.In this paper, the spatial domain multistage interference canceler (SD-MIC) introducing
multistage timing estimation is proposed and its performance is evaluate by computer simulations.The results show that
the timing estimation performance highly improved.
Paper 2.8.3.15
Characterisation of Cross Polarisation Discrimination in Forest Environments
The new services and operating modes introduced in the Terrestrial Trunked Radio (TETRA) standard for digital Private
Mobile Radio (PMR), require an extended investigation of the associated radio channels.Many of the targeted radio
environments were not sufficiently investigated inthe past for the deployment of the existent public cellular systems.
The paper presents an analysis on the cross polarization discrimination in forest environments of radio waves in the 400
and 1900MHz frequency band.The study is based on narrow band radio channel measurements conducted in a typical, in
leaves, forested area in Denmark.Dual polarized antennas were used at both ends of the radio link, thus a full
characterisation of the polarisation matrix in the radio channel was possible.Different base station antenna heights
bellow the forest top level and a car mounted mobile station were used.The results suggest a stronger attenuation of
the horizontally polarised signals and a high cross coupling from horizontal to vertical polarisation in both frequency
bands.In the 1900MHz band the cross polarisation parameters are more dependent on the forest structure and terrain
configuration then in the 400MHz band.
Paper 2.8.3.16
In-Network Evaluation of Mobile Handset Performance
It is well known that mobile handsets perform widely different in actual use, and therefore handsets have to be tested in
realistic scenarios including the users in order to obtain reliable results.One method is to use traditional
propagation measurements, but this has a number of disadvantages.As an alternative, one can use the GSM system for
measurements which, under normal operation, performs measurements of e.g.signal strength during each call.This
information is transferred over the so-called Abis interface in the network.This work investigates evaluation of
handsets based on logging data from the Abis interface.25 test persons are asked to make normal calls with a handset
while walking along a predefined path.During the calls all signalling on the Abis is logged for later processing.5
commercially available handsets are tested, one of which previously has been used for propagation measurements in a
similar campaign.Therefore a comparison of the two methods can be made, in particular whether a similar variation in
performance among the users is obtained.In addition the differences in the performance of the 5 handsets are
investigated.
Paper 2.8.3.17
The Fading Characteristics in the Microcellular Environments Using Deterministic
Prediction Model
The knowledge of the fading characteristics is essential when estimating the performance of wireless communication
systems.So, in order to predict the performance of the communication systems operated in microcellular environments, it
is fundamental to define the microcellular fading signal characteristics.This paper presents the small-scale fading
model in the microcelluar environments, and compares the fading signal of the microcell and the macrocell.
Paper 2.8.3.18
Statistical Characteristics of Pedestrian-Induced Fading
This paper presents a statistical analysis of pedestrian-induced fading on an indoor 2.45 GHz point-to-point link.Using
a deterministic approach (a ray-tracing propagation simulator capable of including the presence of moving human bodies
within the environment), a 150 m-sq open-plan office was simulated.For a specific pattern of pedestrian movements the
resulting fading profile was found to be Rayleigh in nature.The degree of impairment in transmission quality due to
fading caused by moving personnel was investigated for an indoor system with DPSK modulation; an additional 27-dB of
gain would be required to operate at a BER of 10-4 with respect to a non-fading AWGN channel.
Paper 2.8.3.21
Prediction of Fading Signal in a Multipath Environment
The fading envelope encountered in narrowband mobile communications often dominates the communications usage of the
channel.Signal processing techniques are extensively used to mitigate the limitations imposed by the fading, and these
techniques typically require knowledge of the channel transfer function.The possibility of predicting the changing
channel behaviour, in particular the position of fades, is therefore of interest for the subsequent communications signal
processing.Different models of the multipath propagation encourage different algorithms for the model parameter
estimation and channel behaviour prediction.These are reviewed and we present results from simulations showing the
performance and limitations of prediction behaviour.
Paper 2.8.3.24
An Antenna Array Receiver Using Channel Estimation In a DS/CDMA System with M-ary
Orthogonal Modulation
In this paper, an antenna array receiver in a DS/CDMA system with M-ary orthogonal modulation is proposed.At every
antenna element a channel estimation technique is used, which refers to the maximum correlator output of a RAKE receiver
instead of a pilot signal.For the spatial diversity, beamforming weights are formed by the estimated coefficients
combined to the inverse of correlation matrix among antenna elements.And the time diversity is acquired by summing
multipath components at RAKE re-ceiver.Consequently the proposed receiver has 2D (dimensions) RAKE structure.
Simulation results show that the performance improvement of 1.5dB in Eb/No is acquired at a BER=10^(-3) through the
proposed receiver over the re-ceiver scheme for noncoherent detection.Also the results show that at a BER=10^(-2) the
proposed receiver improves about 2.3 times and 3 times system capacity with 3 and 5 antenna elements, respectively.
Paper 2.8.3.26
Efficient Simulation of Fading Channels within a Packet Simulator
Packet level network protocol simulators use simple channel models for computational efficiency.A typical method for
doing this is to compute a packet error probability assuming a certain fading distribution without taking into account
time-correlation.This paper introduces work that has been done to model the effect of small-scale fading (Rayleigh and
Ricean) within the ns network simulator.It allows for the faithful simulation of a complete fading envelope.The fading
models have the appropriate statistics and also time correlational properties obtained from the Doppler spectrum.An
efficient implementation based on a simple table lookup is described.
Paper 2.8.3.27
Subspace-Based Blind Joint Detection of Fading, Asynchronous Cochannel TDMA Signals
We consider joint detection of asynchronous cochannel signals with an antenna array in Rayleigh fading.No training
sequences are assumed, so detection is blind.By exploiting the eigenstructure of the array matrix, we associate the
high-order modes with time-varying channels of different polynomial order.When the time variation of the channels is
piecewise linear over an appropriately selected detector window, our new algorithm - Subspace Blind Joint Detection, or
SBJD - is able to simultaneously distinguish the asynchronous co-channel signals and estimate the Rayleigh channels
(within a phase factor).
Paper 2.8.3.28
Multiple-Input Multiple-Output (MIMO) Radio Channel Measurements
Multiple antennas at both the transmitter and receiver have the potential to significantly increase the capacity of a
wireless channel.To determine the potential of MIMO techniques for 3G and 4G wireless systems, we conducted the first
field tests that characterize the mobile MIMO radio channel in a typical cellular environment.In this paper we present
field test results showing the potential increase in capacity using 4 transmit and 4 receive antennas at the base station
and terminal in a mobile environment.The field test results show that with 4 transmit and 4 receive antennas close to 4
times the capacity of a single antenna system can be supported in a mobile radio channel.
Paper 2.8.3.30
COMPARISON OF THE ELECTROMAGNETIC PROPERTIES OF BUILDING MATERIALS AT 5.8 GHz AND 62.
4 GHz
Future digital radiocommunication systems will offer a wide variety of new applications and services [1].These new
services will require transmission of high data rates and hence, large frequency bandwidth will be needed.Due to the
present congestion of the radio spectrum below 1.8 GHz the use of microwave and millimetre wave bands has been proposed
for these systems.In particular, Broadband Radio Access Networks (BRAN, formerly HIPERLAN) has been assigned a
frequency band around 5.8 GHz [2], while Mobile Broadband Services (MBS) will be operated at 60 GHz [3].These systems
will allow wireless data access at 20 Mb/s and 155 Mb/s, respectively, and will support ad hoc networking of mobile or
highly portable terminals.The deployment of these networks requires the study of the propagation environment and the
measurement of the reflection, transmission and scattering of radio waves by the different obstacles, to obtain data
that can be used to develop and validate radio-planning tools.The electromagnetic behaviour of three typical building
materials as a brick wall, glass, and a plywood panel have been characterised from real measurements.First, the
transmission and reflection coefficients at 5.8 GHz and 62.4 GHz had been measured as functions of the angle of
incidence for both vertical and horizontal polarisation.Then an internal multireflection model [4] has been used to
compute the electromagnetic constants that lead to the best fit between the computed and the measured coefficients.
Measurements at 5.8 GHz were performed at the University of Vigo using an in situ system, based on a frequency swept
wideband radio channel sounder [5,6], while measurements at 62.4 GHz were taken in an anechoic chamber at the University
of Glamorgan [7].Figure 1 shows the measured reflection and transmission coefficients at 62.4 GHz for a slab of plywood
using vertical polarisation.The continuous lines in this figure correspond to the theoretical coefficients that best
fit the measured data, and have been computed using the internal multireflection method.The same procedure was employed
to obtain the relative permittivity for the brick wall, and the glass.Tables I and II show the estimated dielectric
constants for the considered materials using vertical and horizontal polarisation.In the final version of this paper it
is intended to describe both measuring systems and the experimental geometry.Values of reflection and transmission
coefficients as functions of the angle of incidence together with predictions of the multireflection model will also be
presented.
Paper 3.1.1.1
PCS Band Angle of Arrival Measurements using a 4 Element Linear Array
Space division multiple access (SDMA) is an important component of many proposed 4G mobile wireless communications
systems.SDMA makes use of adaptive antenna arrays and signal processing algorithms to differentiate between multiple
mobile users.The SDMA system must adapt to multipath signals with time varying angle of arrivals (AOA).Optimal SDMA
system design requires that AOA statistics be well known.Some AOA data have been published.The data are typically
acquired using either virtual arrays (omni-directional element repositioned between snapshots) or physically rotated
narrow beam antennas.Because these methods are cumbersome and not truly mobile, only limited data are acquired.This
paper will report on the use of a wideband impulse sounding system (PN code implementation) with four simultaneous
channels.The system uses a four element linear array to capture impulses from a mobile transmitter.The AOA pattern may
be determined via post-processing.Statisti! cs from a drive through a suburban neighborhood (Boulder, CO) will be
reported (> 104 impulses).
Paper 3.1.1.2
Isolation and Analysis of the Log-Normal Shadowing Component
Shadow fading correlations are investigated for data collected in the 1900 Mega-Hertz frequency range.
Cross-correlations are computed between signals received simultaneously from two base stations.In analysis of the data,
little or no correlation is found based on the angular separation of the receiver and the base stations.This does not
support the current assumption that shadow fading properties between different base stations are dependent at small
angular separations.Spatial autocorrelations are also computed based on the measurements received from forty-two data
collections at eleven base stations.Fifty percent correlation is found at a distance of approximately 58 meters, while
a twenty percent correlation is determined to be at approximately 103 meters.
Paper 3.1.1.3
Finite Sample Estimates for Mobile Channels
The narrowband channel of mobile communications if often modelled as having a Rayleigh distributed envelope in space (or
time for a moving terminal) and frequency.As the bandwidth increases to become an appreciable fraction of the coherence
bandwidth, the variation in channel gain reduces because of the integration over frequencies which are no longer
uncorrelated.This is the advantage of wideband channels for communications.Similarly, averaging the power in space
results in a decreased gain variation than for a single point in space (cf the advantage of space diversity).For radio
coverage calculations, it is important to estimate the gain with known accuracy.Estimating the correlation coefficient
to a known accuracy is also important for antenna or frequency diversity design.This paper gives results for the spatial
and frequency integration for Rayleigh-distributed envelopes for the mean power and the correlation coefficient.Details
of the derivations will be presented and the results given graphically in terms of the number of samples for a given
accuracy.
Paper 3.1.1.4
Direction Dispersion and Space Selectivity in the Mobile Radio Channel
The analogy between the different types of duality dispersion-selectivity is exploited to derive a figure called the
direction spread which provides a measure of the extent of direction dispersion analog to the delay spread which
characterizes the degree of time dispersion.Another quantity called the maximum spatial Doppler spread is also
introduced which gives an alternative description of direction dispersion.Various theoretical results relate the two
figures above in the 3D and 2D propagation cases.An uncertainty relation between both figures and the coherence distance
of the channel is also established.The impact of these results on the design of linear antenna is discussed.Finally,
various scenarios of direction dispersion relevant for mobile communication are addressed.
Paper 3.1.1.5
Neural Networks for the Planning of Urban Radio Networks
The increasing number of participants in modern mobile radio networks necessitates a more and more detailed and efficient
radio network planning.The basis of a network planning is always the prediction of the quality of transmission between
the transmitter and the participant.The automatic positioning of base station in an urban area needs an accurate and
fast propagation model in order to find the optimal location of the transmitters in a tolerable time.Presently, there
are no satisfying accurate propagation models which are fast enough for algorithms which perform the positioning of base
stations in urban areas in the range of 2500m * 2500m.Empirical models are fast enough but their accuracy is limited
whereas deterministic models as ray tracing are accurate but not satisfying as to computation time.The semi-empirical
model Dominant Ray Paths (DRP) is very promising with regard to accuracy and computation time.A very auspicious
possibility of an accurate and fast prediction model is the combination of the semi-empirical model Dominant Ray Paths
with neural networks.The combination of this semi-empirical model with neural networks for the optimal positioning of
base stations in urban radio networks is presented.
Paper 3.1.2.1
Water Enhancement for Macro amd Microcells
The objective of this proposal is to specifically note the enhancement added to the Lee macro and micocell prediction
models in order to handle the unique impact on radio propagation from as a result of water.
It is generally accepted that water enhances radio signals.However, there are many different impacts at varying levels
dependant on where a mobile is located, relative to positions of water and the base station.An algorithm has been
developed to deal with various scenarios in which water plays a critical role in predicting the effect of propagation
loss.With water enhancement, the model can better predict the radio propagation which has directly impacted the cellular
system engineering, most notably in coverage, HO, interference and thus capacity.
This issue centers around when and in what cases the water enhancement function is implemented.This paper includes high
level flow diagrams and an individual case-by-case analysis.It is assumed that the uplink propagation characteristics
are identical to downlink, therefore only downlink is illustrated
Paper 3.1.2.2
Joint estimation of the space-time distributed signal parameters
Recently several parameteric approaches to estimate the angular spread of a signal as well as its direction have been
proposed.These approaches require that the number of source signals should be less than the number of antennas.
Furthermore, they only model and estimate the spatially scattered sources.In this paper, we extend the idea by modeling
the received signal using reasonable distribution functions in terms of time as well as space parameters.Then we
obtain the maximum likelihood solution for the DOA, angular spread, delay, and delay spread in a computationally
efficient manner.Our simulation study indicates that the proposed algorithm is very promising even at low SNR.
Paper 3.1.2.3
Spatio-Temporal Characteristics at Base Station with Microwave Urban Propagation
The propagation measurements were performed in an urban area at 8.45 GHz.We examined the characteristic of delay and
angle spreads of main waves at the BS receiving antenna.The angle spread is correlated to the delay spread and both
spreads in NLOS environments were larger than those in LOS environments.The spatio-temporal characteristics (at the
BS) described in this paper will be useful for system and cell design of 4th generation multimedia mobile communication
in microwave bands.
Paper 3.1.2.4
A Multiple Input/Multiple Output Channel Model for Simulation of TX and RX Diversity
Wireless Systems
The simulation of space-time receivers for 3G-wireless communication systems that offer the possibility to have both TX-
and RX-diversity requires a MIMO spatial channel model (MIMO multiple input multiple output) which reasonably
characterizes the time-variant effects of the mobile radio channel.This paper describes a space-time vector channel
model with realistic fading simulation for different scenarios and its effective implementation for bit-level
simulations.
Paper 3.1.2.5
A path loss model with height variation in residential areas based on experimental and
theoretical studies using a 5G/2G dual band antenna
This paper presents the pass loss characteristics at 5.2GHz compared with that at 2.2GHz in a residential area by means
of experiment and theoretical analysis.We carried out the propagation measurement by using the dual band antenna 5.2GHz
and 2.2GHz, and compares the measured results.In addition, this paper compares the measured results with the
calculated results using a three-dimensional (3D) ray-tracing approach based on geometric optics (GO) and the uniform
geometrical theory of diffraction (UTD).
Paper 3.1.3.1
WIDEBAND CHANNEL SOUNDING AT 5.1 GHz FOR ANGULAR AND POLARISATION DIVERSITY ON
HIPERLAN TERMINALS
The results of several propagation channel measurement campaigns within the European research project ADAMO, devoted to
adaptivity on the terminal side of high data rate radio links, are described.Wideband characterisation of the channel
at 5.1 GHz has been carried out in several environments, mainly indoor.The directional dependence of one side of the
radio link of sectored radiation patterns, and/or the selection of the polarisation state among 4 possibilities
(linear/circular), have been investigated.It appears that sectorisation alone, but also polarisation diversity mixed
with angular diversity, may significantly improve the delay spread in comparison with a vertically polarised
omnidirectional antenna.
Paper 3.1.3.2
Radiation Phantoms for Handheld Phones
Measurements of radiation efficiency for a handheld phone equipped with a patch and a helical antenna operated near the
human user have been performed.Both measurements include different head plus hand phantom and live persons are
considered.The position of the hand on the phone is found to be the main reason for the large variation in radiation
efficiency among persons.Phantoms used for SAR measurements are found to be too optimistic when considering radiation
and total bodyloss.
Paper 3.1.3.3
Mobile Radio Prediction Model Considering Long Term fading in Urban Microcellular
Environment
This paper proposes a propagation prediction model of received power considering long term fading characteristics for
urban microcellulr communications.Since the long term fading is affected to the communication performance, it is
important to predict the signal level accurately for the communication design and analysis.The received signal strength
in urban mirocellular environment is usually constituted with the direct wave, the ground reflected wave, penetration
effect and the diffracted field, etc.Therefore, we obtained the empirical prediction formulas for the above parameters
using measured and imulated data.It can be seen that the difference between the predicted and measured data is less than
5dB.It can, therefore, be concluded that proposed model is available for the mobile radio prediction model in urban
microcell.
Paper 3.1.3.4
An Analysis of Fading Mechanisms for Fixed Antennas
Recent publications have described the results of extensive channel sounding measurement campaigns which quantitatively
describe the distribution of rays arriving at a fixed measurement receiver.In this paper, we extend this work by
presenting a physical model for the processes that produce the temporal and spatial properties observed during the
measurements.This model is then used to mathematically derive the fading properties, including the autocorrelation
properties, of a fixed antenna in the presence of pedestrian motion.It is shown that the fading severity of a fixed
antenna in the presence of pedestrian motion is dependent upon the static fade depth observed at the antenna in the
absence of the pedestrian motion.
Paper 3.1.3.5
The eta-mu distribution: A General Fading Distribution
This paper presents a general fading distribution, obtained in a closed-form formula, that better describes the
small-scale variation of the fading signal.The distribution is more general than the available small-scale
distributions.In particular, the Nakagami-m distribution can be considered as a special case of this general
distribution.
Paper 3.1.4.1
Application of RBF neural networks to the prediction of
propagation loss over irregular terrain
The availability of digital terrain models has allowed the development of various point to point propagation models, most
of them based on diffraction theory.The main drawback of these models is computation time.Herein, a novel propagation
loss prediction algorithm based on RBF neural networks is presented.It is shown that the model gives good results in
terms of accuracy and statistical modelling of radio channel.Moreover, it shows a great potential for both environment
adaptation and computation time save.
Paper 3.1.4.2
Radio propagation in urban small cells environment at 2 GHz: Experimental
spatio-temporal characterization and spatial wideband channel model.
This paper presents a wideband measurement campaign performed in a typical dense urban environment at 2 GHz.At the base
station, a array antenna were used to study Direction Of Arrival (DOA).Thus, spatial and frequency selectivity
properties of the propagation channel are obtained from the analysis of synthetic wideband propagation parameters.
Finally, a spatial channel model is proposed.It is based on geometrical and stochastic channel modelling approach.Its
relevant parameters were extracted from the analysis of these measurements.
Paper 3.1.4.3
A Stochastic Multiple-Input-Multiple-Output Radio Channel Model for Evaluation of
Space-Time Coding Algorithms
A simple framework for Monte-Carlo simulations of a multiple-input-multiple-output radio channel is proposed.The derived
model include the partial correlation between the paths in the channel, as well as fast fading and time dispersion.It is
demonstrated that the Shannon capacity of the channel is highly dependent on the considered environment.
Paper 3.1.4.4
Prediction of Path Loss in Environments with high rised buildings
Based on a series of measurements in the central area of a city different path loss prediction models have been
investigated.At each measurement position the received power was measured at different heights.Accurate information of
the surrounding buildings was obtained and used in the investigated models.The results show that it is possible to
improve standard deviation of the predictions by 1 dB in the mean case by utilising the information of the surroundings.
Paper 3.1.4.5
MATHEMATICAL MODELS FOR RADIOSIGNALS DYNAMIC RANGE PREDICTION
This paper presents a viable mathematical models and technique for evaluating probability of strong input signals during
reception in space-scattered radio communication networks, particularly high-capacity cellular networks.To achieve this
aim, a method for differential statistical modeling of radio environment is used.This method implies prediction of
statistical characteristics of the ensemble of field (signal) strength values at the reception point.Practical
implementation of this method for FDMA, TDMA and CDMA networks is discussed.
Paper 3.2.1.1
Dynamic QoS Control for Wireless ATM Networks
Abstract-In ATM networks, QoS is determined during the establishment of the connections, so it is fixed and static,
which deals poorly with the mobility and interactivity of wireless multimedia applications.It is essential for wireless
ATM networks to provide a flexible and efficient framework for QoS control, called dynamic QoS.In this paper a
framework for dynamic QoS control in wireless ATM networks is presented, which allows terminal and network-initiated
bandwidth renegotiation to handle wide spatiotemporal traffic dynamics characteristic of mobile multimedia applications.
An implementation perspective of the framework's protocol and software components within mobile wireless ATM system is
given.At the same time we analyzed the effect of wireless link characteristics and AAL2 on QoS.
Paper 3.2.1.2
QoS Constrained Resource Allocation for Multimedia Wireless Networks
To support multimedia applications over the third generation wireless networks, a QoS constrained efficient resource
allocation strategy is essential.We propose a multilevel channel allocation scheme.This scheme not only utilizes the
layer property of MPEG frames and considers the QoS requirements of different data sections but also utilizes the
channel allocation flexibility provided by the CDMA/TDD system architecture to statistically assign available bandwidth,
including codes, time slots, as well as up/down channel capacity, to different traffic types and traffic loads.Instead
of treating the whole video stream as a single type of data, this scheme allocates more network resources to important
traffic.So that the network throughput and the bandwidth efficiency are increased meanwhile the block rate is reduced.
A computer simulation system based on Ericsson*s Wideband Packet-CDMA has been developed.Multiple MPEG video traces
were used to explore the system capacity.The simulation results demonstrated the significant performance improvement
of the! scheme.
Paper 3.2.1.3
Mobility Management and Routing Algorithms for Soft Handoff in Wireless Mobile Data
Network using MGCP
We propose a soft handoff method in packet network for CDMA mobile station and three delay-constrained routing
algorithms for this application that find a tree between multiple sources and multiple destinations.The proposed
algorithms, which provide guaranteed QoS(Quality-of-Service) services at the network layer, are also designed to find
reduced-cost routing trees.The proposed algorithms are verified by simulation, and three algorithm's performances are
compared in view of total tree cost and maximum end-to-end delay.
Paper 3.2.1.4
A Framework for Mathematical Modeling of 2-tier Hierarchical Mobile Ad-Hoc Networks
In this paper, we propose a framework for mathematical modeling of 2-tier hierarchical mobile ad-hoc networks
considering terminal mobility.In the proposed model, each terminal has statistical model to describe its mobility based
on parameters such as a mean speed, an initial angle and so forth.With this mobility model, the probability that a
slave terminal exists in the specific cluster, i.e.the paging area of the corresponding master terminal is derived.And
the performance measures about a mobile ad-hoc networks such as mean number of hops, new call blocking rate, call
dropping rate, paging cost, and so forth are evaluated.
Paper 3.2.1.5
Performance Evaluation of Hybrid OFDM/CDMA/SFH Approach for Wireless Multimedia
This paper deals with a novel approach to wireless multimedia applications.In contrast to the well known MC-CDMA system
developed by Linnartz et al, our system is called the Hybrid approach.It combines optimally OFDM/CDMA/SFH to achieve
similar results but with drastically reduced hardware.The system is also superior to MC-CDMA in terms of BER due to SFH
which MC-CDMA does not use owing to hardware complexity.This proposal was first presented in the ACTS summit at
Sorrento, Italy last year by the authors.Our paper for this conference presents simulation results in AWGN and fading
channels.It also concludes with a proposal for achieving high bit rates at 60 GHz frequency.
Paper 3.2.2.1
Soft Reservation Multiple Access with Priority Assignment(SRMA/PA): A Novel MAC
Protocol for QoS-Guaranteed Integrated Services in Mobile Ad-Hoc Networks
In this paper, we proposed a novel MAC protocol called SRMA/PA(Soft Reservation Multiple Access with Priority
Assignment), which is the dynamic reservation TDMA scheme for the mobile ad-hoc metworks.A main goal of this protocol
is to provide a means to guarantee the QoS requirements of the real-time services in a flexible manner while maximizing
the statistical multiplexing gain in the integrated service applications.We note that the proposed approach is not
much involved with the additional complexity as compared with the existing protocols.
Paper 3.2.2.2
HOLPRO: A New Rate Scheduling Algorithm for CDMA Downlink Networks
We consider the downlink rate scheduling problem for CDMA networks with multiple users carrying packets with different
types of traffic ('voice/audio only', or 'data only' or mixed traffic), each of which has its own Quality of Service re-
quirements that need to be satisfied.At each timeslot, we assign a pseudo-proba- bility to the head packet of each user,
which is then normalized by the packet length.We serve the user with the maximum normalized pseudo-probability and then
we repeat the procedure for the user with the next maximum normalized quantity,as long as we have power resources.We
compare our algorithm to the two best allo- cation schemes known for similar systems, namely the 'Earliest Deadline
First', and its modified version of 'Powered Earliest Deadline First' and conclude that we outperform both.
Paper 3.2.2.3
Link layer buffer size distributions for FTP and HTTP/1.0 applications in an IS-2000
system
In this paper, we provide the link layer adaptation and retransmission buffer size distributions for HTTP and FTP
application in an IS-2000 system.The results are given for different TCP window sizes, TCP segment sizes, air link FER
and data rates.Furthermore, a Reno version of TCP is considered and the maximum TCP segment is fixed to 576 Bytes.For
HTTP application, the number of parallel TCP connections is limited to either 1 or 4
Paper 3.2.2.4
Mobile IP based DECT multimedia architecture for IMT-2000
The article describes a network architecture based on the DECT common air interface to provide IP services in the arena
of third generation of mobile communications.IP datagrams are delivered to DECT users through the DECT packet-mode
bearer service, achieving more efficient usage of radio resources and supporting multimedia services and applications.
The proposed architecture augments the DECT voice network with IP routers and backbone links - the DECT Packet Network
(DPN).The DPN is linked to the global IP based Internet through the border gateway (BGW).The mobile IP (M-IP) protocol
is adopted for global IP mobility and automated, non-interactive re-attachment of terminals to the Internet and
Intranets.
Paper 3.2.2.5
Multimedia Mobile Terminal P-link Station with TDMA-TDD technology
A personal repeater for PHS, *gP-link Station*h (PLS) is developed.PLS can be registered with the public PHS carrier.
PHS terminals for private systems can be connected to the public PHS network via PLS.It enables to use various PHS
terminals by only one pub-lic telephone number.Furthermore, PLS decides whether the arrived call is voice or data, and
then forwards the call to a suitable terminal that is a handy-phone or a data terminal such as PDA (Personal Digital
Assistant) or Note PC.Since time division du-plex (TDD) system is adopted in PHS, PLS is realized with only one
transmit-ter-receiver (TRX).As a result, the equipment is very small (about 90g).PLS can relay a 64kbit/s data
communication, too.In this paper, we describe new functions and new techniques using in the P-link Station.
Paper 3.2.3.1
An Enhanced Reliable Multicast Protocol for Wireless Environments
This paper presents a performance study, using both analytical modeling and simulation techniques, of a new end-to-end
reliable multicast protocol for use in environments with wireless access.The proposed protocol, known as the reliable
mobile multicast protocol (RM2), divides a multicast tree into sub-trees where subcasting is applied within these
relatively smaller regions using a hierarchical tree of retransmission servers (RSs).More importantly, RM2 uses a
dynamic retransmission strategy to switch between multicast and unicast retransmission modes according to the amount of
extra load generated in the network as well as at the wireless interfaces by packet retransmissions.It is shown
through both analytical modeling and simulation that RM2*s dynamic adaptation is not only important but also necessary
when considering mobile wireless access.RM2 assumes that the network is formed of multicast routers and that cells are
big enough for users to join and leave mu! lticast groups.The RSs perform selective retransmissions on the basis of
negative acknowledgements they receive.RM2 dynamically establishes the subcasting regions while taking into account
retransmission costs.
Paper 3.2.3.2
Application of Erasure-only Decoded Reed-Solomon Codes in Cell Recovery for Congested
ATM Networks
Congestion at any switching node, in ATM networks, may result in cell discards.This may bring about unsatisfactory
transmission quality, particularly in time sensitive data such voice and video.Forward error correction, in general, and
Reed-Solomon codes in particular offer viable avenues to recover lost cells.Two erasure-only correction decoding methods
based on Berekamp-Massey and Euclidean algorithms are described.These techniques are computationally efficient and are
suitable for the application.It is proposed that an interleaved Reed-Solomon code with erasure-only decoding be employed
for cell recovery when transpoting MPEG-2 packets through ATM networks.Specifically it is recommended that a shortened
version of (255, 251) Reed-solomon code, with interleaving depth of 47 be selected for this application.
Paper 3.2.3.3
On-Demand Associativity-Based Multicast Routing for Ad Hoc Mobile Networks
Multicast has emerged as a very desirable feature in communication networks.With multicast, data can be distributed to
multiple recipients in an efficient and economical manner.In this paper, we presents a performance evaluation of novel
multicast routing strategy for mobile ad hoc network environment, which is characterized by highly-dynamic topology with
constrained bandwidth and limited power.The Associativity-Based Ad hoc Multicast (ABAM) protocol establishes multicast
session on demand and utilizes association stability concept, which is introduced in ABR (Associativity-Based Routing)
protocol for mobile ad hoc unicast routing.Performance of ABAM is simulated and compared with flooding- based multicast
routing protocol.The results show impressive throughput and very low communication overhead.
Paper 3.2.3.4
Optimum Rate and Power Adaptation for Multirate CDMA
We determine the optimal centralized adaptive rate and power control strategy to maximize the total average weighted
throughput in a generic multirate CDMA system in the presence of slow fading.An average power and instantaneous bit
error rate (BER) constraint is assumed at the transmitter with conventional matched filter detection at the receiver.Our
results are general enough to apply to several multirate CDMA schemes : multi-channel, multi processing gain,
multi-modulation CDMA or hybrids of these.We derive closed form expressions for the optimum rate adaptation boundaries
between different rate regions without assuming any symmetries between the users.We use the optimum adaptation scheme to
obtain numerical results for optimum average throughputs of different multirate CDMA schemes.Moreover we show that as
the users move around within the cell, i.e.as the propagation path loss and the distribution of the channel fading of
each user changes, the optimum power and rate control strategy can adapt by simply scaling the channel fades of the
users.
Paper 3.2.3.5
Quality of Service Control over GPRS Data Network
The general packet radio service (GPRS) is a packet data service for phase 2+ of Global System for Mobile Communications
(GSM).It not only defines the packet-switch data service on top of GSM, but also tries to provide quality of service
(QoS) guarantees on packet flows.Although the technical specifications define a number of QoS parameters and service
classes, the QoS control mechanisms and procedures are out of the specifications.In this paper, we elaborate the
admission control, resource reservation, policing, and scheduling mechanisms, and apply them to different nodes of a
GPRS data network.Cooperated by these nodes which perform different QoS control procedures, the QoS requirements
specified in a service contract can be easily achieved.
Paper 3.2.4.1
IEEE 802.11 AND ETSI HIPERLAN TYPE 1: PERFORMANCE COMPARISON UNDER INFLUENCE OF a
BURST-NOISE CHANNEL
We have compared different performance measures of the two standardized WLANs, IEEE 802.11 and ETSI Hiperlan Type,
considering two essential factors: BER of the fading air medium and number of stations in the ad-hoc network.Regarding
the Hiperlan, most of the performance measures are insensitive to the number of stations due to sophisticated but complex
EY-NPMA MAC protocol.However, its high overhead redundancy causes great throughput degradation as BER is increased.The
relatively simple and low overhead CSMA/CD protocol in the IEEE 802.11 WLAN produces lower discard probability and higher
normalized throughput given same normalized offered load, and it is less sensitive to fading air medium.
Paper 3.2.4.2
TCP over Asymmetric CDMA Radio Links
In TCP-supported traffic flows like file downloading and Web browsing, the connection is inherently asymmetric since TCP
data segment sizes and TCP ACK segment sizes are different.To exploit this asymmetry in wireless Internet access through
third-generation CDMA mobile cellular systems, different uplink and downlink channel data rates can be allocated.In this
paper, we investigate the TCP performance over asymmetric CDMA radio links in cdma2000 system.It is shown that the
appropriate downlink/uplink data rate combinations should be determined in order to achieve comparable system performance
as that of symmetric radio links, and the appropriate combinations vary with the radio channel conditions, specifically
Frame Error Rates (FERs).These are mainly due to the fact that RLP (Radio Link Protocol) layer frame error recoveries
at uplink and downlink channels are dependent on each other.To use our results in practical systems, we propose a
procedure on channel data rate allocations for TCP-supported data services in order to achieve acceptable system
performance and use channel resource efficiently.
Paper 3.2.4.3
Block Codes with Soft-decision Trellis Decoding in Compressed Image Transmission over
Rayleigh fading channel
Performance of a new trellis decoding method of block codes based on the GAC structure is studied over Rayleigh fading
channels in this paper and further researches are also carried out to introduce this maximum-likelihood decoding method
to image transmission systems.Results show that this decoding technique adapts to Rayleigh fading channels
successfully and can bring significant performance improvement to image transmission systems over mobile fading channel
with rather low decoding complexity.
Paper 3.2.4.4
Evaluation of Mobile Ad Hoc Networking Techniques in a Cellular Network
A Mobile Ad hoc Network (MAN) consists of mobile nodes, which are free to move about arbitrarily.These mobile nodes
incorporate routing functionality, due to which a backbone network is no longer essential.The ad hoc topology may
change with time as the nodes move or adjust their transmission and reception parameters.A MAN is an autonomous
system, which can have gateways to a fixed network.This paper studies the performance of routing protocols, developed
for MAN networks, such as the Ad hoc On Demand distance Vector, Source Tree Adaptive Routing and dynamic source routing.
Paper 3.2.4.5
Erlang Capacity of CDMA Systems with Adaptive Arrays
We present a technique to calculate the number of subscribers which can be supported in a CDMA system while using
adaptive arrays.Results presented using this technique show the tremendous capacity increases possible while using
adaptive arrays.The advantages of adaptive arrays over sector antennas and beamformers is quantified by considering
Erlang capacity and spatial clustering of subscribers.This study has practical implications in wireless local loop
systems and results presented clearly highlight the benefits of using a dynamic spatial processor like adaptive arrays
as compared with fixed patterns used in sector antennas.We also consider the effects of high-powered multimedia users
in a voice-dominant system and results presented illustrate that by using smart antennas, it is possible to maintain a
sizeable voice capacity while admitting small number of multimedia users.Note** A hard copy of this paper was sent to
Mr.Lipoff on Feb.10/00
Paper 3.3.1.1
Performance of TCP/IP over IS-2000 Based CDMA Radio Links
In this technical report, we investigate the system performance of Internet protocol TCP/IP integrated with Radio Link
Protocol (RLP) over IS-2000 based CDMA (i.e., cdma2000) lossy radio links.We evaluate overall system performances with
the RLP specified in IS-707 designed to be used with IS-95-A.In addition, we present RLP enhancements suitable for
high-bandwidth cdma2000 system, especially for how to deal with large Physical Layer frame size and high Physical Layer
Frame Error Rate (FER).We show significant performance improvement over i.i.d.frame error channels by subdividing
Physical Layer frame to smaller Logical Transmission Units (LTUs) at Multiplex Sublayer.
Paper 3.3.1.2
Performance of multicarrier CDMA with MSK modulation and one-bit differential
detection in a multipath fading channel
A direct sequence code division multiple access (DS_CDMA) muticarrier system with minimum shift keying (MSK)modulation
and differential detection is proposed.This system has the advantage of simplere implementation than that using binary
phase shift keying (BPSK) modulation with conventiaonal matched filter receiver.It is shown that the performances of
the two systems are close.
Paper 3.3.1.3
a
Performance of Space-Time Multi-user Detection in Synchronous DS-CDMA Systems with FEC
Coding
The main topic of this paper is to examine the advantages offered by RS codes with space-time multi-user detection
algorithms.As a case of study, we consider the application of RS coded with the space-time minimum-mean square error
(MMSE) multi-user detector.First, we consider the performance of the RS coded space-time MMSE-MUD using adaptive
antennas over an AWGN channel.Secondly, we will examine the same detector over a single path Rayleigh flat fading
channel.
Paper 3.3.1.4
Intelligent Call Admission Control for Differentiated QoS Provisionings in Wideband
CDMA Cellular Systems
Differentiated quality-of-service (QoS) provisioning for wireless multimedia CDMA systems is an important issue.In this
paper, we propose intelligent call admission control to support differentiated QoS requirements for wideband CDMA
cellular systems.The intelligent call admission controller (ICAC) contains a fuzzy call admission processor to make
admission decision for a new call request by considering QoS measures of all service types, the predicted next-step
existing-call interference, and the estimated new-call interference.We employ pipeline recurrent neural network (PRNN)
to predict the next-step interference of existing calls and utilize the fuzzy logic theory to estimate the interference
of a new call based on knowledge of effective bandwidth method.Simulation results show that ICAC can always guarantee
QoS requirements for all types of traffic, while the conventional signal-to-interference (SIR)-based CAC cannot keep; and
the former has lower blocking probability and higher system capacity than the latter by an amount of 10% and 9%,
respectively.Also, ICAC is more adaptive and stable in wideband CDMA cellular systems.
Paper 3.3.1.5
Dynamic 3G Network Selection for Increasing the Competition in the Mobile
Communications Market
This abstract presents a conceptual framework, being developed within the UK Mobile Virtual Centre for Excellence
consortium, where mobile users are able to dynamically select the serving network operator on a per call basis.This is
made possible by the specification of a middleware platform where network operators offer communications services and
service providers tender service contracts.Based on a reorganisation of the telecommunications business model, the
approach is expected to increase competition between 3G operators and providers.
Paper 3.3.2.1
Efficient Water-filling Algorithms for Gaussian Multiaccess Channel with ISI
This paper describes efficient water-filling algorithms for Gaussian Multi-access Channel with Intersymbol Interference
(ISI), where all users have equal priorities.In a multiuser OFDM system, these algorithms compute the optimal input
power spectral density for each user that maximizes the uplink data rate of the common receiver.The proposed algorithm
for two users gives an exact solution and has a complexity of O(NlogN).The proposed heuristic algorithm for K (K>2)
users has a complexity of O(K^2NlogN), which is much lower than that of previoulsy known methods (O(N^(K(K-1)/2)), and
achieves more than 98% of capacity in all simulations.
Paper 3.3.2.2
Dynamic Time-Division-Duplex Wireless Local Loop
There are many benefits in using time division duplex (TDD) instead of frequency division duplex (FDD) schemes in fixed
wireless cellular systems.To name a few; channel reciprocity for the single carrier frequency used on both up and
down-links will allow easy access to channel state information, reduced complexity of RF design, much higher flexibility
in handling dynamic traffic, simpler frequency plan, etc.However, there exists a serious limiting factor in using
dynamic-TDD (D-TDD) in cellular systems.This is due to a steady interference on uplinks in a cell caused by down-link
transmissions of other cells.Simulation results show in D-TDD cellular systems, performance is unacceptable, when
omni-directional antenna is used at base stations.Simulation results have also demonstrated a great potential for smart
antennas in fixed D-TDD bandwidth-on-demand wireless systems.
Paper 3.3.2.3
Admission Control for Future Multi-Service Wideband Direct-Sequence CDMA (WCDMA)
System
For CDMA-based third-generation mobile systems, the capacity of the system is dependent on the total amount of
interference received at each base station and will vary with time.If admitting an user when the system is congested,
the link quality for all other active users will degrade, and the result will be call dropping.Traditionally, to avoid
call dropping, one uses some sort of admission control algorithm that will block newly arrived users if the system is
in a congested state.These algorithms tries to measure, in different ways, how much resources the system has left, and
if there still is room, they will accept a new call.In third-generation mobile systems there will be a more complex
traffic situation with multiple services.Using these new assumptions on traffic, three different call admission
control algorithms were compared in terms of dropping probability, blocking probability, weighted outage and absolute
throughput.The algorithms being evaluated are Received Power Call Admission Control (RPCAC), Predictive Call Admission
Control (PCAC), and a Modified Predictive Call Admission Control (MPCAC).RPCAC algorithm blocks new users when the
received power at a base station gets too high while the PCAC algorithm tries to predict the traffic situation in a near
future in terms of something called equivalent bandwidth and blocks a new user if the equivalent bandwidth demand and
the already used equivalent bandwidth is higher than the predicted value.The last algorithm, MPCAC, is a combination of
RPCAC and PCAC.Four different types of services, two symmetric and continuous types and two asymmetric and
discontinuous types were implemented.As shown, none of the tested algorithms evaluated cope well in a multiple service
environment.Though the MPCAC algorithm can be said to offer best performance.
Paper 3.3.2.4
Analysis of the Uplink of an Asynchronous Multi-user DMT OFDMA System
The joint effect of time offsets, frequency offsets, and multi-path fading in the uplink of an asynchronous multi-user
system for wireless communications deploying discrete multi-tone modulation and demodulation is studied through analysis.
In such a scenario multiple access interference arises.We derive analytical expressions for the multiple access
interference, and we study its statistics.The MAI strongly depends not only on the aforementioned impairments but also
on the tone assignment algorithm used to multiplex the users.Based on our analysis, it is shown that the insertions of
appropriate time and frequency guard intervals, and the accurate selection of the tone assignment algorithm, minimize the
MAI so that a proper trade off with spectral efficiency can be met to optimize system performance.
Paper 3.3.2.5
Radio Link Performance and Traffic Capacity of Indoor Wireless Systems Integrated with
Outdoor Cellular
In this paper we report on investigations of indoor cellular networks for wireless access in a corporate environment.The
work is an evolution of that reported in \cite{VTC00Spring}, where the reference scenario of an integrated
private/public environment was presented and preliminar performance results were presented for a single floor building
with simulcast coverage.While retaining the assumption of spectrum sharing between the outdoor cellular and the indoor
system, in this paper the more general scenario of a multi-floor building is considered.In this context frequency reuse
is required to achieve adequate capacities in large buildings and our investigation aims at finding a proper trade-off
between cluster size and multicast area extension, given the limited number of available frequencies.Performance results
are reported in terms of maximum traffic supported for given requirements on blocking probability, call dropping
probability and outage probability of the radio link.Throughout the work, specific reference to classical and recent
(such as AMR, Adaptive Multi-Rate) GSM set of specifications is made.Moreover, allocation of frequencies to the indoor
system in a spectrum sharing context with outdoor cellular is addressed.
Paper 3.3.3.1
Admission Control in Wireless Systems with Heterogeneous Traffic and OverlayCell
Structure
This paper proposes and analyzes the performance of admission control policies (ACPs) for wireless cellular networks
carrying two classes of service.Each class may have its own bandwidth requirements, call intensity and session
duration.A two-dimensional Markov chain model is used to derive traffic performance measures for each class of service,
such as the probability of blocking, the probability of handover failure, and the probability of forced termination.
Sharing of resources among services is adopted, in order to prevent trunk inefficiency.However, since the class
requiring larger bandwidth suffers larger blocking, an ACP is investigated that protects handovers of that class by
dropping of ongoing calls of the other class.Its ability to meet different design requirements is discussed and its
performance evaluated under various traffic distributions.Moreover, an extension of the ACP is proposed in a two-tier
cellular system, where ongoing calls to be dropped at the lower tier can be moved to the upper tier.It is observed that
this an effective technique to manage heterogeneuos service requests with sharing of various set of resources.Each
set belongs to a certain coverage tier in a hierarchical coverage architecture.Since upper tiers are allocated
decreasing amount of resources, lower bandwidth calls are preferably served by upper tiers when traffic congestion
occurs at lower tiers.
Paper 3.3.3.2
A New Adaptive Modulation Strategy for Broadband COFDM-based Communication Systems
with Constant Transmission Rate
A new adaptive modulation system based on a COFDM/TDD system is proposed that provides a fixed data transmission rate of
20 Mbps over typical urban or hilly mobile radio channels.The new algorithm uses the bit loading adaptation method of
Fischer and Huber and we show how the convergence rate of the new algorithm can reach 90% of its target bit rate after
only one iteration and it can reach the target bit rate after only two iterations with negligible performance
degradation.Most other algorithms require many more iterations than this.The sensitivity of the new system to a variety
of channel impairments such as: ICI, ISI,rapid time variations and frame timing misalignment is assessed for both types
of channel.Finally the performance of this system is compared to a pre-equalisation-based system employing channel
inversion at the transmitter.In both cases, the performance is compared on the basis of (i) a perfect channel estimate
and (ii) a noisy channel estimate obtained using one-dimensional scattered pilot channel estimation method.To achieve a
realistic model a true TDD link between the transmitter and receiver is simulated so that the uplink and downlink which
carry both data symbols and the information about the SNR at the individual sub-carriers also suffer channel impairment.
The results show that the new system significantly outperforms non adaptive systems.
Paper 3.3.3.3
Integrated Air Interface Access Schemes for Broadband Wireless Communications
Broadband Wireless Access (BWA) operating in the LMDS band will facilitate the seamless integration with wireline
networks, widening significantly the servi- ces and applications in wireless environments.In this paper we consider the
protocol that coordinates the multiple access techniques to gain access to other networks.The Cell Mapping Multiple
Access (CMMA) protocol is explored, particu- larly its ability to integrate the various air interface access schemes,
which will support dissimilar services and applications from local, metropolitan and wide area networks.To meet the
various needs, the air interface access schemes integrate core protocols (STM,IP,ATM) and network technologies (Circuit,
Packet, and Cell Switching)components, mapping them onto Virtual Regions for the provi- sion of common access services
categories.
Paper 3.3.3.4
A MODIFIED HOPFIELD NEURAL NETWORK ALGORITHM FOR CELLULAR RADIO CHANNEL ASSIGNMENT
As the frequency of the mobile radio communications is limited, the channel assignment problem deserves more attention
in order to use the available frequency spectrum with optimum efficiency.The neural networks have been used in the
dynamic channel assignment to rearrange the available channels.The channel assignment problem is formulated as an
energy minimization problem that is implemented by a modified discrete Hopfield neural network.In many cases the
techniques using neural network have failed in solving the problem, probably due to the local minima problem.In this
paper we propose a method that will guarantee that the neural network will skip the local minimum and in all cases will
converge to optimum arrangement of the channels, which allows maximum utilization.The procedure presented in this paper
is based on multilevel rearrangement of the input channels before applying to the Hopfield neural network parallel
algorithm to decrease the number of iterations and improve the convergence rate.The results of the proposed algorithm
is compared with that of [1], [2].Three constraints are considered in this paper as in [1], [2], which are: Co-Site
Constraint (CSC), Co-Channel Constraint (CCC), and Adjacent Channel Constraint (ACC).The goal of the channel assignment
problem is how to satisfy these constraints, which are given by the compatibility matrix, during the assignment of the
required channel number (RCN) for each cell.The compatibility matrix C=cij is defined as n*n symmetric matrix, where n
is the number of cells in the mobile radio network, and cij is the minimum frequency separation between a frequency in
cell #i and another in cell #j.The number of channels needed for each cell #i is presented by the RCN matrix R=(ri ),
where 1 Paper 3.3.3.5
A Novel FHSS Multiple-Access System Using M-ary Orthogonal Walsh Modulation
A novel frequency-hop spread-spectrum multiple-access (FHSS-MA) system employing M-ary orthogonal Walsh modulation with
noncoherent demodulation is proposed.Two simple and accurate Gaussian models for the multiple-access interference from
both the dehopped slot and its neighboring slots are developed and used to analyze the performance of the proposed
system for synchronous and asynchronous hopping networks for both nonfading and Rayleigh fading channels.The proposed
system significantly improves the network throughput compared to the FHSS-MA systems employing MFSK modulation.
Paper 3.3.4.1
Quality of Service and Grade of Service Optimisation with Distributed Dynamic Channel
Allocation Schemes Based on Hopfield Neural Network Algorithms
3G wireless systems will have to support a large number of mobile subscribers by fulfilling tight QoS requirements with
limited spectrum allocation.Over the recent past new computational strategies such as neural networks and stochastic
search techniques have been studied to dynamically allocate channels in an optimum way.This paper presents a
comparative study of distributed and centralised Hopfield Neural Network-based (HNN) dynamic channel allocation schemes,
by highlighting how distributed HNN-DCA algorithms can achieve an optimum balance between QoS and GoS thereby improving
call capacity in a distributed scenario.
Paper 3.3.4.2
High-rate OFDM Codes for Peak Envelope Power Reduction and Error Correction
It is well known that orthogonal frequency division multiplexing (OFDM) is an effective technique to combat multipath
fading in wireless communications.A main disadvantage of OFDM is however that multicarrier signals inherently exhibit a
high peak envelope power ratio (PEPR), because of the statistical independence of the carriers.Attractive codes based on
complementary sequences, which can be used for both decreasing the PEPR and correcting channel errors, have been proposed
for multicarrier systems.We are now proposing hybrid codes with these two properties, PEPR reduction and error
correction.Furthermore, our codes improve both the PEPR reduction and the coding rate in MPSK systems, compared with
complementary codes.In this paper, we discuss about the performance of our novel hybrid codes applied to combined
amplitude and phase modulation schemes such as MQAM systems.As far as we know, any PEPR reduction codes for these
modulation schemes have never been proposed.Our new codes function well and enable highly efficient wireless
communications, in conjunction with adaptive OFDM systems which employ variable-rate MQAM modulation techniques.
Paper 3.3.4.3
Trunking Efficiency and Load Balance for Multiple-Carrier CDMA Systems
When the number of carriers in a wireless network is increased, conventional wisdom (based on analog systems) is that,
the required hardware resources (typically radios) increase linearly, and the capacity increases non-linearly.The
latter is the well-known capacity trunking efficiency.For multiple-carrier CDMA systems, however, such wisdom does not
apply anymore, as revealed in this paper.Based on analyses and sophisticated system-level simulations, we have found
little or no capacity efficiency, but some hardware resource efficiencies.So for a CDMA system with N-carriers, its
total capacity is most likely to be N times the capacity of a single carrier, and it may require less than N times the
hardware resources required by a single carrier.Furthermore, we found that such hardware efficiency can be effectively
achieved through load balancing algorithms, or software, which may reduce system complexity considerably (i.e., hardware
is not necessarily shared or c! onnected across carriers).In this paper, we study three different load balancing
algorithms based on: (1) available power in each carrier, (2) the usage of the Walsh-codes in each carrier, and (3) the
order of arrivals (round robin).The results show that, all of them can effectively reduce the required hardware
resources, but one may perform better than the others.Different mobile hashing results were also taken into
consideration in the simulations.
Paper 3.3.4.4
Spatial CDMA - A Distributed Multiple Antenna Access Method for Broadband Wireless
Communication
We present a new technique called Spatial CDMA for multiple antenna communications.The transmit and receive antennas
are distributed either locally or over a wide area.We take advantage of the spatial signature of transmitting and
receiving geographic pattern to significantly improve the capacity and reliability of wireless access.Specifically,
multiple access capacity is shown to increase linearly with the number of receiving antenna, and the probability of
error decreases exponentially.With the new communication scheme and protocol, broadband wireless communication is
feasible at a hundred megabits per second and beyond.
Paper 3.3.4.5
Theoretical Analysis of the Pilot Tones Assisted COFDM System over Fast Multipath
Fading Channels
Fast fading is the commonly encountered phenomenon for an OFDM system which has long symbol duration (equivalent to the
system having a large number of subcarriers).It introduces the inter-channel interference (ICI) which leads to the loss
of orthogonality between subcarriers.Even worse, it gives an irreducible error floor of the system's bit error rate
(BER).In this paper, we analyze the ICI's statistic properties caused by the fast fading and derive the BER formula of
the system assisted by the pilot tones over a time-varying multipath fading channel.In order to minimize the variance
of the estimation error, samples taken from the pilots were filtered using a Wiener filter.The estimation method using
pilots allows us to calculate the values of the ICI.Therefore, the ICI can be suppressed using a frequency domain
equalizer and the error floor will be removed.
Paper 3.4.1.1
Pre-equalization of MIMO Wireless Channels With Delay Spread
We consider a downlink finite impulse response (FIR) multi-input mulit-output (MIMO) wireless channel with L taps.It is
shown that such a channel can be pre-equalized by an FIR MIMO transmit filter with only L taps, if the angle spread due
to the different multipaths is sufficiently large at the transmitter.Assuming a transmit power constraint and complete
channel knowledge, a closed form solution for the transmit pre-equalization filter is derived.
Paper 3.4.1.2
Combining Turbo-Code and Co-channel Interference Cancellation
In this report we prove the improvement of performance by combining Turbo-Code and Co-channel interference canceller
assisted by RLS-MLSE.This system estimates Desired signal and Interference signal separately.The output of MLSE is the
estimated desired signal on survival path of Viterbi estimater, which is the soft value.And then input the soft value
which does not contain interference element to Turbo-decoder.The performance of this system is better than the system
only with MLSE.
Paper 3.4.1.3
Adaptive Successive Interference Cancellation for the IS-95 Uplink
In this paper, we consider an adaptive successive interference cancellation (ASIC) system for separating and recovering
direct-sequence code-division multiple-access (DS/CDMA) signals on the uplink as specified in Interim Standard 95
(IS-95).The ASIC is a multistage receiver that sequentially estimates and cancels user signals according to their
power levels.Each stage consists of a conventional matched filter (MF) receiver followed by an adaptive interference
canceler (AIC).We illustrate the improved performance of the ASIC compared to the conventional SIC (CSIC) for near-far
conditions and frequency-selective fading channels.Additional details are provided in the extended abstract.
Paper 3.4.1.4
Rigorous Characterisation of Multiple-Input Multiple-Output (MIMO) channels for
Space-Time Communications
This paper describes a MIMO channel characterisation activity, in which the measurements are made within the coherence
time of the channel.It is believed that these results are unique, and a valuable contribution to space-time channel
models.
Paper 3.4.1.5
Application of RS-coded MPSK Modulation Scenarios to Compressed Image Communication in
Mobile Fading Channel
Two different RS-coded MPSK schemes for Rayleigh fading channel over which compressed image is transmitted are
considered in this paper.Combing the performance of RS codes and MPSK modulation obtain a theoretical formula on
bit-error rate of the coded modulation schemes in Rayleigh fading channel.The two RS-coded MPSK scenarios are used in a
typical image communication system in mobile fading channel.The simulation results show that the high-efficient coded
modulation schemes can improve the system performance.RS-coded MPSK scheme is expected to play an important role in the
mobile multimedia communication
Paper 3.4.2.1
Parallel Decoding of Turbo Codes using Soft Output T-Algorithms.
One of the drawbacks of Turbo codes apart from the encoding latency due to the interleaver is the high complexity of the
iterative soft output decoding of the component codes, which directly leads to a significant amount of decoding delay.
The worst case decoding delay/complexity of turbo codes may be reduced by using W (W>1) processors in a pipelined or
parallel structure.This paper shows that soft-output T-algorithms can provide further reduction in the worst case
decoding delay if used in a parallel decoding structure but not in a pipelined structure.A low complexity soft output
T-algorithm, T-SOVA, based on the soft output Viterbi algorithm, has also been proposed.The T-SOVA provides performance
practically equivalent to that of the SOVA and succeeds in lowering the decoding delay considerably when used in a
parallel decoding structure
Paper 3.4.2.2
Amplitude and phase estimation considerations for asynchronous CDMA with
Superorthogonal Codes and Successive Interference Cancellation
Successive interference cancellation, in conjunction with very low rate convolutional codes, has been shown to approach
the Shannon capacity of a Gaussian channel [1].This approach to CDMA is very well suited to asynchronous (uplink)
wireless channels.However, accurate phase and amplitude estimation is required for effective operation.In this paper,
we develop a power control algorithm specifically designed to relax the requirements on estimation accuracy.Using this
power control algorithm in conjunction with superorthogonal codes and successive interference cancellation, it is shown
that even with average estimation error up to 30%, the capacity over an IS-95 CDMA system can be increased by an order of
magnitude.
Paper 3.4.2.3
RAKE Receiver with Adaptive Interference Cancellers for a DS-CDMA System in Multipath
Fading
In this paper, a new RAKE receiver with adaptive interference cancellers is proposed for a DS-CDMA system in multipath
fading.The proposed adaptive RAKE receiver exploits antenna diversity and adaptive interference cancellation to
mitigate the effect of both multipath fading and multiple-access interference.The performance of the proposed receiver
is computed by computer simulation for the various numbers of antennas and RAKE fingers.It is shown that the proposed
receiver achieves significant performance improvement over a conventional RAKE receiver.
Paper 3.4.2.4
Joint Equalization and Decoding of Trellis Coded Signals using the Generalized Viterbi
Algorithm
Abstract- In this paper, a new receiver structure is described for trellis coded signals transmitted over frequency
selective channels.This receiver is based on the use of the Generalized Viterbi Algorithm (GVA).Several applications
are proposed involving convolutional or block codes.Simulation results show that the proposed receiver structure
provides close to optimal performances with reasonable complexity.
Paper 3.4.2.5
Performance of HD-Parallel Interference cancellation in DS-CDMA System
This paper considers a simple model for hard-decision multiple parallel interference caancellation in a CDMA system.
Because practical systems will experience timing errors, the effect of timing errors need to be analyzed.This paper
obtained a snalytical expressing for the probability of bit error in HD-PIC with timing error.Analytical result are
shown to agree well with simulation.
Paper 3.4.3.1
Reducing the Error Floor in Turbo Codes by Using Non-Binary Constituent Encoders
Turbo codes represent one of the most important advances in coding theory in recent years.However, one of the problems
with turbo codes is that they present an error floor, with stays even for relatively large values of Eb/No.We propose a
class of non-binary constituent encoders, and show that the error floor is reduced when they are utilized.The basic idea
is to improve the profile of d2^E (i.e., the output euclidean distance distance between input sequences which differ in
two bits and produce an error event.) This approach can be applied with other techniques aimed at reducing the error
floor by interleaver design, therefore producing further reduction in the error floor.
Paper 3.4.3.2
A New Efficient Decision-Aided ISI Canceler for Mobile Communication Systems
Intersymbol Interference (ISI) can be effectively cancelled by using a Decision-Aided Canceler (DAC).In such a scheme
the introduced ISI is modeled as a linear combination of past and future symbols.Since the true future symbols are
unavailable, most of the existing DAC schemes operate with preliminary (tentative) estimates of these symbols which are
provided by a linear equalizer.Thus the performance of a DAC scheme depends heavily on the performance of the linear
equalizer.In the proposed DAC scheme the tentative symbols are provided by a block frequency domain Decision Feedback
Equalizer.The proposed scheme outerperforms the existing DAC schemes in both steady-state performance and convergence
speed, and at the same time it exhibits a much lower computational complexity.Its good performance is retained even
under hostile conditions such as those encountered in wideband mobile communication systems.
Paper 3.4.3.3
New TCM codes for AWGN and ISI Channel by Matched Symbol-Mapping Method
In this paper, a new design method for trellis coded modulation (TCM) is presented in order to improve the coding gain
for wireless communications through AWGN and intersymbol interference (ISI) channel.Generally, TCM construction is
based on two steps of encoding and mapping using set partitioning.However, the conventional TCM schemes which are
realized by the optimization of squared Euclidean distance, the number of the shortest error event path, and the product
distance, are already listed in [1].Therefore, this implies that new TCM-codes may be constructed by developing the
step of mapping while holding the previously design-values.In this work, a definition for matching the distribution of
symbol error probability to the signal subset construction known as matched symbol-mapping is proposed.Some TCM signal
subsets of this new design method is developed based on the state transition metric (STM) first introduced in [1][2].
Next, several new codes have been devised by the proposed method with throughput rates (Rb) of 1, 1.5, 2.5 and 3
bits/sec/Hz.They have been simulated in AWGN, and in multipath Rayleigh fading (or ISI) channel with signal
equalization by sub-optimum soft output equalizer (SSE).Results show that in AWGN channel all new codes perform better
than those in the literature given by Mayr [1], Periyalwar [3], and Divsalar [4].A maximum gain of up to 0.5 dB is
achieved at 10E-5 of BER, with codes of Rb 1.5 and 3 compared to the best codes.Furthermore, in ISI channel the new
code with Rb of 1.5 performs best.Meanwhile, performance of new codes at Rb of 1, 2.5, and 3 seems to match the
performance of codes found in the literatures for this channel.In summary, the proposed symbol mapping method in this
paper can be used successfully to construct better codes for application in AWGN channel and in ISI channels where SSE
is used.Some results are presented in Figure 1 and Figure 2 with Rb of 1.5 and 3 bits/sec/Hz respectively.
Paper 3.4.3.4
Interference Suppression Receiver with Adaptive Antenna Array for Code Division
Multiple Access Communication Systems
Recently an interference suppression receiver for CDMA system was proposed to suppress MAI.This receiver only uses
temporal information of the received signals.In our paper, an adaptive Direction-of-Arrival (DOA) tracking algorithm in
antenna array signal processing for CDMA communication systems is introduced and applied to the interference suppression
receiver.The proposed adaptive DOA tracking algorithm tracks the maximum output power of the desired user signal.Only
the knowledge of the first order statistics of the MAI is required.No matrix operation and training sequence are
required.Hence, the tracking algorithm is simple and has a low computational load.The tracking algorithm uses the
decision feedback information to assist the tracking of the DOA.
Paper 3.4.3.5
A new space-time minimum variance receiver for CDMA systems and its performance
analysis
In a mobile radio channel, received CDMA signals suffer from the multiple access interference (MAI), the
multipath-induced delay spread, and the fading.A conventional receiver with a single antenna, such as the RAKE receiver
cannot exploit the spatial structure of the received signal.In this paper, we propose a new space-time minimum variance
(MV) receiver for CDMA systems.We also investigate the influence of spatial parameters such as the angular spread of
incident signals and the antenna element spacing.It appears that the proposed receiver shows superior performance to
the single antenna MV receiver in multipath environment and even in the presence of a non-zero angular spread.
Furthermore, the proposed algorithm is insensitive to the antenna spacing, too.
Paper 3.4.4.1
Combined DA/DD/NDA channel estimation techniques for downlink WCDMA
Two novel combined methods for channel estimation are analyzed and compared in terms of BER and complexity.They are
introduced in order to increase the system performance when pilots are time-multiplexed with data symbols.The simulation
results justify the choice of these methods as viable solutions for downlink WCDMA.
Paper 3.4.4.2
Evaluation of the MAP decoding for the Turbo codes of IMT-2000
One of the primary ITU objectives for IMT-2000 is Improved operational efficiencies, particularly for data and
multimedia services.Data and multimedia services require the BER below 10-6.To do this, specification groups
accepted the turbo code for one of the channel coding schemes.Even though the turbo code has good performance in
itself, the decoding complexity and its delay are critical points in implementing it.In this paper, various simulations
are performed using standards proposed by 3GPP and 3GPP2.These two standards use CDMA in FDD mode.We use the AWGN
environment to simulate them.In the specification by 3GPP2, 26 different turbo-encoding cases exist as Radio
Configuration (RC).And in the specification by 3GPP, 4 cases exist as data rate.We varied the data rate, code rate and
the number of iteration for decoding according to Eb/No values.Performances of Turbo decoders using Max Log-MAP and
Log-MAP are compared.Finally, the case using window framing method and the case not using it are compared.As a
conclusion, from the many simulation results, we propose various choices to the designers who want to design turbo
decoder for IMT-2000 system.
Paper 3.4.4.3
A Spreading Sequence Allocation Procedure for MC-CDMA Transmission Systems
Multi-Carrier CDMA (MC-CDMA) combines the Orthogonal Frequency Division Multiplex (OFDM) modulation and the CDMA
multiple access scheme where the spreading is performed in the frequency domain.As the transmission over a frequency
selective channel breaks the orthogonality between user codes and creates Multiple Access Interference (MAI), the system
performance is reduced.In this paper, we propose to limit the MAI by optimizing the spreading sequence allocation
procedure among a given spreading sequence family.Based on an analytical analysis of the MAI, we propose a selection
criterion of the spreading sequences and derive a simple formulation of the allocation procedure.We evaluate the
performance by simulations for different multipath channels with different single user detection techniques such as
Equal Gain Combining (EGC) and Minimum Mean-Square Error Combining (MMSEC).We show that our optimal spreading sequence
allocation procedure improves all the more the! performance in terms of averaged Bit Error Rate as the channel frequency
correlation is important.
Paper 3.4.4.4
Improved Viterbi Decoder Metrics for Two-Stage Detectors in DS-CDMA
An improved estimate of the variance of the residual Multiple Access Interference (MAI), after interference cancellation
(IC), is presented for two-stage detectors with the conventional first stage.Based on that, modified variance-dependent
Viterbi decoder branch metrics are proposed and significant performance improvement over the Euclidean branch metric of
the standard Viterbi decoder is demonstrated.
Paper 3.4.4.5
Iterative Super-Exponential-Estimator for Fast Blind Channel Identification of Mobile
Radio Fading Channels
An iterative algorithm for blind channel identification (no training symbols necessary) based on the
Super-Exponential-Algorithm [SW93] is shown.On the assumption of independent, identically distributed (i.i.d.) data the
algorithm has fast convergence properties.It is robust with respect to system overfit (supernumerarily assumed channel
coefficients converge to zero) and influence of modest additive white Gaussian noise even in mixed-phase moving average
channels.Also the combination with training symbols is possible to improve the performance - blind and data aided
algorithm together in one.
Paper 3.5.1.1
Performance of TCM Schemes over Equalized Channels
This paper presents a performance evaluation of TCM schemes over ISI channels with receivers using equalization.The
asymptotic gain introduced by TCM coding schemes using the Ungerboeck's criterion is derived in taking into consideration
the effects of the channel impulse responses.Based on the expression of the asymptotic gain, the effectiveness of a TCM
coding scheme using the Ungerboeck's criterion applied to a particular ISI channel can be assessed.Depending on the
channel impulse response (CIR), a TCM scheme using the Ungerboeck's criterion can have an inferior performance as
compared to the uncoded system.
Paper 3.5.1.2
Optimal Adaptive Precoding for Frequency-Selective Nagakami-m Fading Channels
DMT transmissions with optimal power and bit loading are suitable for wired-line applications but have high complexity
when it comes to wireless time-varying environments.Adaptive modulation on the other hand, assumes that training
sequences are available to provide an accurate estimate of the channel parameters, while the channel statistics allow to
evaluate average performance.Random channel modeling is a powerful tool for assessing wireless systems performance, but
can be also be instrumental in optimizing the modulation.We develop optimal loading strategies for frequency selective
fading, assuming OFDM modulation and by modeling the channel impulse response as an FIR filter whose taps are Nagakami-m
correlated fading processes.The design minimizes the BER for a given average transmit power.Channel statistics need to
be updated at a very slow rate when compared to the exact channel status information (CSI), which reduces complexity of
our adaptive OFDM scheme compared to a standard DMT approach.This also alleviates the need of training and allows us to
incorporate partial channel knowledge in the design.Interestingly, our derivations identify the optimal solution for the
limiting case where the channel transfer function is exactly known at both transmitter and receiver.
Paper 3.5.1.3
Blind Adaptive Multiuser Detection for Multirate CDMA
Blind adaptive multiuser detection for multirate CDMA is investigated within a generalized framework.The framework is
based on a discrete-time model for truncated window FIR linear multiuser detectors for variable spreading factor (VSF)
CDMA systems.For VSF CDMA the linear minimum mean squared error (LMMSE) decentralized multiuser detector has been shown
to be a periodically time varying (PTV) filter composed of p time-invariant branches where p is periodicity of the
multiple access interference.We present a general closed form expression for the truncated window PTV LMMSE detector for
any VSF multirate system and we propose a method of obtaining this detector adaptively without the need for training data
by applying the constrained minimum output energy (CMOE) blind algorithm.Furthermore we propose a method of choosing the
number of PTV LMMSE filter branches when the receiver has no a priori knowledge of the data rates of the active users.
Simulation results are presented to illustrate the advantages of using the new technique.
Paper 3.5.1.4
Soft-Output M-Algorithm for the Concatenation of Detecting and Decoding
For digital communications over frequency-selective channels, detector is often concatenated with a decoder to reach high
quality of communications.If the detector delivers soft-output to the decoder, the maximum likelihood decoding or the
turbo detecting and decoding can be performed and the error rate performance will greatly outperform that of the decoding
using hard decision of the channel symbols delivered by the detector.A reduced complexity MAP algorithm is the
reduced-state soft-output trellis- equalization algorithm incorporating hard or soft feedback.This algorithm corresponds
to the delayed decision-feedback sequence estimation (DDFSE) algorithm or reduced-state sequence estimation (RSSE)
algorithm.Here we propose another reduced complexity MAP algorithm that corresponds to the M-algorithm and called the
soft-output M-algorithm (SO-M-algorithm).
Paper 3.5.1.5
Demodulation of D2PSK with a DPSK Detector and Improved Error Performance in AWGN
In this paper, a new receiver scheme for demodulation of D2PSK signal is proposed.Basically, it consists of a
first-order differential detector (i.e.a conventional DPSK detector) with decision feedback, followed by a differential
decoder.Decision is made on the FOPD rather than the SOPD, and the information-carrying SOPD is recovered by
differentially decoding of the decided FOPD*s.As a result, the effect of the AWGN is significantly reduced; hence the
error performance improves.An analysis shows that the symbol error rate of D2PSK with such a receiver is approximately
twice as high as that of DPSK.Computer simulation of this new scheme for quaternary (M=4) D2PSK has been carried out and
verified the analysis.
Paper 3.5.2.1
A method to improve the transmission performance under slow to fast fading environment
In the high speed mobile radio communication especially beyond 2Mbps under vehicular environment, multi-path and
time-varying fading is one of the most serious problem.An equalizer is one of the most effective scheme which can
combat it, however burst error often remains after equalization at slow fading frequency and equalizer itself can not
track the fading channel fluctuation accurately at fast fading frequency.We propose the combination method of
countermeasure for slow and fast fading.The countermeasure for slow fading is to generate and add fading-like
fluctuation to transmitter artificially by multiplying cosine(2*pi*fadd*t) for one branched data and sine(2*pi*fadd*t)
for the other branched data.Here, the pi is the circular constant and the fadd is the frequency to be added forcibly.
Thanks to this, long term fade duration which causes burst error can be avoided without any feedback information on
channel condition such as closed loop power control command.The countermeasure for fast fading is to adaptively change
the transmission symbol rate by tradeoff between channel tracking performance and multi-path number restriction.Thanks
to this, equalizer can offer the best performance with limited hardware complexity.This combination method is also
suited for software radio technique.
Paper 3.5.2.2
Performance Evaluation of a Direct Conversion Radio for Tri-Band GSM and GPRS
The performance of a novel direct conversion radio for GSM tri-band and GPRS applications is evaluated.An overview of
the architecture is presented, along with results of an analysis of the radio performance.The advantages of the
architecture are discussed, particularly with respect to frequency plan and DC offset reduction.Measured receiver
performance is presented for sensitivity in GSM and DCS1800 bands, as well as blocking performance and AM detection
performance.The measured performance of the novel transmitter is also presented.Measured performance of a fractional-N
synthesizer is presented for phase noise and lock time, demonstrating that it is suitable for GPRS applications.
Paper 3.5.2.3
Evaluation of link-level performance improvements by using smart antennas for the
TD-CDMA based UTRA TDD mobile radio system
For third Generation mobile radio systems like the TD-CDMA based UTRA TDD mode the use of smart antenna technology for
down- and uplink promises a substantial performance improvement.This paper describes a link-level simulation
environment, the used smart antenna technology and presents link-level simulation results for different scenarios.The
article gives some ideas for what can be expected in terms of interference rejection when using smart antennas for UTRA
TDD.
Paper 3.5.2.4
A Fast Selective-Direction MMSE Timing Recovery Algorithm
For the EDGE system with multiple antennas, spatial-temporal equalization can reduce the effect of multipath fading,
intersymbol interference and co-channel interference, thereby increasing the capacity and range.With time varying delay
spread, accurate timing recovery is crucial for good equalizer performance especially when the equalizer length is short
because of the limited number of training symbols.In this paper, we propose a fast selective-direction minimum
mean-square error (MMSE) timing recovery algorithm.The new timing recovery algorithm determines the estimated burst
timing and processing direction for the equalizer by computing the MMSE for a decision feedback equalizer in both the
forward and reverse time directions.Simulation results show that the 2-branch receiver with our techniques requires
about 5 dB lower signal-to-interference ratio than a previous approach for a 1% raw BER in EDGE.
Paper 3.5.2.5
ITERATIVE CHANNEL ESTIMATION AND DECODING WITH PRODUCT CODES IN MULTICARRIER SYSTEMS
The time-varying mobile communication channel makes channel estimation for multicarrier systems a demanding task at the
receiver.To allow for coherent detection, the two-dimensional channel transfer function must be estimated.We present a
joint channel estimation and decoding method which is based on the A Posteriori Probability (APP) calculation algorithm.
An iterative estimation and decoding loop over inner estimator/product code and outer soft in/soft out APP decoder allows
to further reduce the bit error rate.
Paper 3.5.3.1
Coding of PPM Based Modulation Techniques to Improve the Performance of Infrared WLAN's
In this communication we consider the use of TCM codes with PPM based modulation techniques for infrared WLAN's.The
modulation techniques we consider are: -APPM (Amplitude and Pulse-Position Modulation)[1], hybrid modulation where
information is conveyed both in amplitude and position of one pulse.-OPPM (Overlapped Pulse Position Modulation)[2]
where the symbols contain a pulse transmitted in non-orthogonal positions, i.e.allowing some overlapping between pulses
of different symbols.The computation of the capacity of these modulation techniques allowed us to conclude that these
schemes can be used to improve the performance of PPM without bandwidth expansion, using Trellis-Coded Modulation (TCM)
codes.In [1] the best codes for the Ax2-APPM (based in 2-PPM) schemes, (A=2 and 4) and the results show that
non-negligible coding gains can be obtained with trellis codes of moderate complexity.In the present communication we
extend the work of [1] by deriving the best TCM codes for Ax4-APPM and OPPM.
Paper 3.5.3.2
Optimal sequences to suppress the multiuser interference for CDMA systems
The criterion and algorithm to optimize the spreading and despreading sequences for CDMA systems are given.The
numerical results indicate that, compared with the conventional Gold sequences, the optimal sequences can take
advantages of the multipath channel, and so greatly decrease the mulitiaccess interference.
Paper 3.5.3.3
Turbo Decoding in a Rayleigh Fading Channel with Estimated Channel-State Information
In this paper, a new method to estimate channel state information is proposed for a turbo code in a Rayleigh fading
channel with imperfect fading estimation.It is shown that the proposed estimation scheme for the channel reliability
factor provides an accurate estimate and the performance of Log-MAP algorithm using the estimated channel reliability
factor agrees with that of Log-MAP algorithm using the true channel reliability factor.It is also shown that through
the use of the correct channel reliability factor, the performance gain of Log-MAP algorithm over Max-Log-MAP algorithm
does not decrease although fading estimation error increases.
Paper 3.5.3.4
A searcher for the synchronization channel of WCDMA
In this paper, we design a searcher for the synchronization channel of WCDMA.The simulated correlation properties of
PSC and SSC codes are illustrated.From these simulation results, methods for slot identification and code group
identification are introduced and designed.Matched filter and correlator are designed and a new algorithm for code
group searching is proposed.Both the slot and the group identification can be done within 20 msec with this hardware.
Paper 3.5.3.5
Reduced-Complexity MAP Equalizer for Dispersive Channels
We present a computationally efficient equalizer for generating soft information for M-PSK modulation over dispersive
channels.The proposed equalizer has a forward and backward recursion structure similar to the classic BCJR MAP
algorithm; however, the complexity of this proposed equalizer is orders of magnitude less than that of the BCJR
algorithm.This is accomplished by constructing a reduced-state trellis, as in a decision feedback sequence estimator.In
order to preserve consistent state definitions for the two passes in the MAP formulation, the backward pass in our
algorithm does not construct its own trellis, but rather takes the reduced-size state space constructed in the forward
pass as given and proceeds to compute the required soft information using this trellis.The performance of this DFSE-MAP
equalizer is evaluated in a receiver structure that iterates between the equalizer and a convolutional decoder.Using the
EDGE air interface and Typical Urban Channel of GSM, we show that our iterative receiver improves the block error rate by
3dB.In this example, by using the DFSE-MAP equalizer rather than the full MAP algorithm, the number of states per
trellis stage is reduced from 4096 to 8.
Paper 3.5.4.1
Mobile Radio Multi-Link Analysis
It is well known that the fading phenomenon, which inherently exists in most radio links, constitutes one of the boundary
conditions of radio communications design.A widely recognized practice for combatting short-term deep signal fades in
digital communications over such a time-varying channel is to redundantly deploy a number of channels, simultaneously,
instead of using a single propagation link between the transmitter and receiver.This technique is called multichannel
(multilink) reception\cite{price62}, a name which is synonymous with the diversity combining\cite{brennan59} used in
classical radio communications.If two or more radio links of a diversity channel are separated sufficiently in space,
frequency or time, and sometimes in polarization, the fading on the various links is presumed to be statistically
independent.As a consequence in most applications it is unlikely that all paths fade deeply at the same time.This, in
turn, implies that reliable communications is possible over the surviving paths when some of the paths experience deep
fades.This is the mechanism by which a diversity technique works in a fading environment.Even in a non-fading
situation where a single tansmitter-receiver combination is not possible, multi-channel communications can be made to
perform with the same transmitting power that is used in a single channel.
Paper 3.5.4.2
An Effective CIC (Co-channel Interference Canceller) Scheme for Multi-rate CDMA
This paper proposed an improved CIC scheme lessenning tha noise enhancement.
Paper 3.5.4.3
A Novel Coherent Demodulation for M-QAM OFDM Signal Operating in the Burst Mode
This paper proposes a novel coherent demodulation method for Orthogonal Frequency Division Multiplexing (OFDM) systems
with Multi-level Quadrature Amplitude Modulation (M-QAM) that are operating in a burst mode such as wireless LAN
communications systems.The salient feature of the proposed method is that two training symbols placing at the start of
every burst are used both for the synchronization of received burst frame and the estimation of channel frequency
response under the frequency selective fading environments.Furthermore, this paper proposes a novel phase tracking
method for compensating the rotation of signal constellation points due to the residual frequency estimation error.The
proposed coherent demodulation method offers excellent C/N performance under severe frequency selective fading
environments.
Paper 3.5.4.4
A Novel Symbol Frame and Carrier Frequency Synchronization for Burst Mode OFDM Signal
This paper proposes a novel synchronization method of jointly estimating symbol frame timing and carrier frequency
offset for orthogonal frequency-division multiplexing (OFDM) systems operating in the burst mode such as wireless LAN
communications system.The salient feature of the proposed method enables the rapid and accurate synchronization for the
burst mode OFDM signal even under the presence of very large frequency offset, low C/N and frequency selective fading
environments by using two training symbols placing at the start of burst.
Paper 3.5.4.5
Performance of an Experimental 384 kb/s 1900 MHz OFDM Radio Link In a Wide-Area
High-Mobility Environment
The first phase of an experimental investigation into future generation high-speed, high-mobility, wireless data
communications techniques using OFDM has recently been completed and the performance of a prototype has been measured
under a variety of radio channel conditions.This paper reports on a prototype radio link intended to provide a
high-speed downlink for wireless Internet access.Practical RF impairments and realistic algorithms have been studied to
address the emerging need for data network access from high mobility platforms at wired LAN-like data rates.The results
presented in this paper are based on a real-time DSP-based implementation of a practical OFDM radio link.Another paper
presents the details of the implementation.To summarize, the system under study provides 384 kb/s end user data rates in
an 800 kHz bandwidth, using one transmitter and two receivers with equal gain antenna combining and with rate *
Reed-Solomon channel coding.The paper will present insights into the interactions between modulation, coding, channel
conditions, real-time parameter estimation, and overall performance.
Paper 3.6.1.1
Transmission of embedded VBR multimode encoded speech on UMTS Common Packet Channels
Embedded and variable bit-rate (VBR) multimode encoding is a suitable technique that may be used to obtain a smooth
degradation of quality at high loads and heavy interference.In UMTS such coding schemes can be profitably exploited by
transmitting the high priority information (core coding) on dedicated channels of guaranteed minimum QoS and the low
priority bits (enhancement coding), whose nature is more bursty, on shared channels.On UMTS uplink Common Packet Channel
(CPCH), congestion co ntrol policies are implemented at MAC level, where frequent resource assignments are sent according
to the cell traffic load and channel quality measures.This resource allocation technique has been compared with
traditional transfer o n UMTS variable-bit-rate dedicated channels in the hypothesis of voice encoded w ith a VBR
multi-mode encoder.
Paper 3.6.1.2
A connection admission control using transient outage probability in CDMA systems
This paper proposes a transient (predictive) connection admission control (CAC) scheme using the transient quality of
service (QoS) measure for CDMA cellular voice systems with bursty On-Off sources.Based on the outage measures, we
compare transient outage performance against steady-state outage performance.We need an approximate approach for
real-time CAC applications.We derive the transient outage probability as the QoS measure using the fluid-flow model.
Numerical results show that the predictive CAC is a promising approach for the multicell CDMA systems.
Paper 3.6.1.3
Classification and Characterisation of Mobile Broadband Services
In this paper, the available data about mobile broadband services/applications classification is put together and their
characterisation parameters are identified, enabling some insight on new approaches for performance analysis in MBS.
Based on the recent UMTS standardisation and on the GSM evolution one starts by identifying the new UMTS/MBS boundary in
terms of data rates and user mobility.Two different aspects of importance are then considered.On one hand, a
classification for services and applications is proposed based on the I.211 ITU-T Recommendation.It distinguishes
between interactive and distribution services, i.e., between bi-directional and unidirectional ones, widely speaking.On
the other hand, a taxonomy is proposed for applications characterisation parameters, which are being divided into five
different types: main ones, traffic and communications parameters, service components and operation environments as well.
A detailed description of these parameters and their range of variation will be given in the full paper for some examples
of services and applications.
Paper 3.6.1.4
A Cost Effective Paging Scheme for IMT-2000 Systems
IMT-2000 systems are envisioned to allow mobile users to communicate regardless of their locations and home registration
systems, providing free roaming between different service areas with different technologies, system providers.In
general, location tracking schemes require intensive computation and cause heavy signaling traffic to search for a mobile
terminal in such a situation.In this paper a new paging scheme is introduced to reduce the paging costs and delays in
IMT-2000 systems.The paging process is performed using the concept of boundary location register which is used to
maintain the roaming information of mobile users crossing the boundary of two systems.This scheme not only significantly
decreases the paging cost but reduces the average paging delays also.Numerical results demonstrate cost-effectiveness
and delay reduction for one-step and multi-step paging procedure.
Paper 3.6.2.1
Hardware-Fitted Modeling and Simulation of QoS of VoIP over a Wireless LAN
This paper details the VoIP Quality of Service (QoS) analysis of an IEEE802.11 type wireless VoIP network as the total
number of background voice users increase.A hardware-fitted simulation model is used to analyze the behavior of the
wireless subnet-VoIP QoS hardware measurements are taken for a small number of users, then duplicated and extended well
beyond available hardware resources within an OPNET computer simulation.Based upon the defined acceptable QoS limits,
the maximum number of wireless VoIP users is determined for a variety of packet sizes.Upon an initial comparison
between IPv4 and IPv6, the final results and comparisons are based upon the latter Internet protocol.
Paper 3.6.2.2
Uplink capacity of multirate multicell CDMA wireless local loop system with narrowbeam
antenna and SIR based power control
In this paper, a theoretical model for uplink capacity analysis of DS-CDMA based , power controlled wireless local loop
system with narrowbeam antenna is presented.First, interference from surrounding cells in the multicell environment is
investigated.From relevant simulation results, system capacity can be increased by subscriber directional antenna and
larger capacity improvement can be made if antenna array is equipped at the base station.Next, we studied the capacity
performance in the multimedia multirate situation.The effect of other important factors on the capacity is also
presented for comparison.
Paper 3.6.2.3
Diversity Combining of a Fast Varying, Correlated Multipath Fading Channel for
Direct-Sequence Spread-Spectrum Systems
In this paper, diversity combining of a fast varying, correlated multipath fading channel for direct-sequence
spread-spectrum systems is investigated.The correlated multipath fading channel is modeled as a vector autoregressive
(VAR) process.Unknown parameters of the VAR model are estimated using a expectation maximization (EM) technique.The
proposed technique does not require the derivatives of the log likelihood function, and hence is computationally
efficient.The proof of global optimum is also provided in this paper.Through computer simulations, a near optimum
bit-error-rate is achieved.
Paper 3.6.2.4
A CELLULAR ARCHITECTURE FOR SUPPORTING GEOCAST SERVICES
Geocasting is a specialized multicast technique for mobile systems where messages are multicast to mobile nodes within a
given region.In this paper, we address the geocasting problem for cellular mobile networks.The crucial components of
the problem are, the geolocation mechanism, dispersion of the geolocation information, and geocast message routing and
delivery.Routing and addressing issues and control packet structures have been introduced and treated in the
literatures.In this paper, we present a cellular architecture to support geocasting with minimal overhead signaling,
subject to the quality of service requirements of the particular geocast applications.
Paper 3.6.2.5
Design and implementation of an experimental wireless terminal
This paper presents an analysis of the design requirements of a portable wireless terminal constructed from off-the shelf
components.Considerations include performance and power usage.An implementation of the terminal is presented.
Paper 3.6.3.1
Soft Handover Gain in WCDMA
Firstly this paper estimates the advantage of using soft compared to hard handover in order to extend coverage, since,
when soft handover is concerned, an additional reduction of shadow fading margins is obtained exploiting the possibi-
lity of performing Maximum Ratio Combining (MRC) in downlink and Selection Ratio Combining (SRC) in uplink.Soft handover
gain is calculated as a function of soft handover add threshold, hard handover hysteresis and handover delay.The second
part evaluates the extent to which additional interference, due to soft handover in downlink, influences the system QoS,
expressed as Outage Probability..Since this interference depends on handover parameters and traffic load, the outage
probability is calculated as a function of soft handover add threshold and average system load.
Paper 3.6.3.2
Voice/Data Transmissions in Common Packet Channel of 3GPP
The 3GPP adopts the common packet chanel (CPCH) to carry small and medium size packes.In this paper, we propose four
schemes to provide voice/data transmissions over CPCH in 3GPP and exhibits each performance in terms of quality of voice
communications such as dropping probability and data traffic throughput under the condition of bounded delay through
the commputer simulation and analysis.Three schemes are based on the basic scheme, the channel assignment scheme, and
the monitoring scheme.The fourth scheme for voice/data transmissions is the flexible channel assignment scheme with
preemption.In addition, when the data rate for CPCH channels for data terminals is K times as that of CPCH channels for
voice terminals, the effect of the parameter K is investigated, too.
Paper 3.6.3.3
Performance Analysis of Group Handoff in Fiber-Optic Cellular System
When groups are reorganized by dynamic group simulcasting, a cell which is located in a group can be transferred to the
other group.In this case, all calls in that cell must be handoffed simultaneously to the target group.This type of
handoff is named 'Group Handoff'.In this paper, we analyze the performance of soft handoff algorithm which is used as
the group handoff procedure in the CDMA based fiber-optic cellular system.We assume CDMA based system.The performance
of Intergroup soft handoff algorithm is analyzed by using the birth-death process model.We evaluated the performance of
group handoff algorithm in fiber-optic cellular system and could see that the capacity of this system is increased as
the handoff region is diminished or the channel capacity is increased.
Paper 3.6.3.4
On the Rake Receiver Performance
In this paper we study the Rake performance for the UMTS FDD mode.We begin by investigating the amount of diversity that
we can recover from multipath Rayleigh fading channels with delays separeted by less than the chip period.In this
framework, we evaluate the impact of the channel estimation bias caused by multipath interference.Then, abstraction done
on this bias, we analyse the Rake performance degradation caused by channel estimation noise.Finally, we study the
influence of the intersymbol interfernce for small spreading factors.
Paper 3.6.3.5
Dealing with location uncertainty in mobile networks using Contextual Temporal Fuzzy
Cognitive Maps
Mobility management in telecommunication networks is basically concerned with location management and handoff
management, which allows a call in progress to continue as the Mobile Terminal changes channels or moves between cells.
Location management deals with locating roaming mobile terminals (MTs) for call delivery.In location management, the MT
periodically performs location registration to notify the network of its new access point and store changes to its user
location profile.Most of the existing techniques for location tracking use probabilistic methods.In this paper we
propose a new location tracking strategy based on common sense reasoning and qualitative spatial reasoning to compute
changing mobile locations and orientations.We use a Fuzzy Cognitive Map (FCM) as a spatial decision support system and
the FCM is built over a Geographic information system.The proposed method is compared with the existing methods.
Paper 3.6.4.1
The Rough Road to IMT-2000 RTT Standard
The vital importance of standards for compatibility and interoperability across a wide range of network industries is
clear.Equally apparent is that the growing rewards from winning, or to some degree, controlling the outcome of the
standardization process has made reaching consensus on standards much more difficult.Today, such agreements are
essential if society is to enjoy the full benefits of global information and communications network, and of which
wireless technologies will play a major role A new mobile system for worldwide use is now being developed to enhance and
supersede current Second-Generation digital systems.Third-Generation Mobile Systems will provide universal personal
communications to anyone worldwide.The rough road to develop radio interface specifications for IMT-2000 has been
hampered by intellectual property right and international trade disputes.A formal request by the ITU-R for
submission of candidate radio transmission technology RTTs for IMT-2000 was distributed by the ITU, with a closing date
of June 1998.A comprehensive set of radio interface specifications, incorporating the flexibility required to
seamlessly evolve current mobile networks towards IMT-2000, were approved on November 5, 1999.This paper reviews the
international standardization of third-generation mobile communications systems and explores the potential for conflict
between the standards process and intellectual property rights (IPRs).
Paper 3.6.4.2
Link Performance Evaluation of EGPRS in LA and IR Modes
In this paper, the link performance of EGPRS is evaluated for LA and IR under interference and coverage limited
scenarios for some typical channel radio conditions.The paper will cover: 1.An overall description of EDGE including
various code rates, modulation and burst structure.2.An overall description of the link quality control mechanisms, LA
and IR.3.Link performance results for EGPRS in LA Mode.4.Link performance results for EGPRS in IR Mode.5.
Conclusions.
Paper 3.6.4.3
Performance Evaluation of Cellular Mobile Systems with Successive Co-Channel
Interference Cancellation
Our paper presents an analytical framework for the performance evaluation of cellular mobile radio systems equiped with
smart antenna systems.We focus on low-complexity systems which are able to successively suppress the strongest active
interferers.The desired user fading statistics is assumed to be flat Rayleigh, Rician, or Nakagami, whereas the
interfering signals are assumed to be independent and subject to flat Rayleigh fading.The paper will include the
derivation of generic closed-form expressions for the total interfering power probability density function (PDF) as well
as the carrier-to-interference ratio PDF after interference cancellation.Based on that, we obtain exact closed-form
expressions for the outage probability, and average error rate for various M-ary digital communication schemes of
current practical interest.These formulas are computed numerically for several scenarios of practical interest.More
specifically, we study the effect of the type! and severity of fading as well as the impact of traffic loading on the
performance of the cancellation scheme under consideration.We also compare our results with the performance of
classical cellular systems and show the performance gain expected from the proposed successive interference cancellation
scheme.
Paper 3.6.4.4
Grouped Parallel Multiuser Detector for CDMA Mobile Communication
A new grouped parallel multiuser detector is proposed and the algorithm is derived in this paper.The complexity of this
detector is linear to the number of users and the performance is better than the decorrelating detector.The detection
delay is smaller than the decision-feedback detector.Numerical results show that the BER of the grouped parallel
multiuser detector goes to some value when the MAI power is 3dB higher than the useful signal power, so this detector
can resist near-far effect efficiently for CDMA mobile communication.
Paper 3.6.4.5
Adjustment Loop Transmit Power Control during Soft Handover in CDMA Cellular Systems
In the downlink of CDMA cellular systems, traffic capacity is increased with fast closed-loop Transmit Power Control
(TPC).During soft handover, however, the balance of downlink transmit power among base stations is lost due to
reception errors of the TPC commands, and the gain of soft handover is reduced, i.e.downlink transmit power per mobile
station increases.In order to solve this problem, adjustment loop TPC is proposed, with which the balance of downlink
transmit power is recovered without frequent exchange of control information among base stations.
Paper 3.7.1.1
Optimizing Antenna Parameters for Sectorized W-CDMA Networks
We optimize antenna parameters, such as the opening angle, with respect to capacity for a W-CDMA cellular system.
3-sector sites as well as 6-sector sites are considered for both UL and DL.System simulations show that the capacity is
maximized for 40 deg opening angle for 6-sector cellular systems, and 80 deg respectively 65 deg for the two types of
regular 3-sector cellular systems.This holds for different handover margin, orthogonality factor and attenuation
factor, and for UL as well as for DL.It is shown that a hard requirement on the front to back ratio is not necessary.A
novel theoretical model for the capacity is presented and compared to the simulations.The results given by the
theoretical model show good agreement with the simulation results.
Paper 3.7.1.2
An Exclusive Intergroup Handoff Algorithm in Fiber-Optic Microcell/Picocell Radio
System
In this paper, we propose and analyze a new intergroup handoff scheme which is exclusive in fiber-optic cellular system.
In the proposed scheme, a user handoffs with keeping current channel.The proposed scheme has many advantages such as
the increase of channel efficiency,the reduction of handoff refused probability, and the decrease of signal traffic for
handoff.According to the numerical results, we can see that the proposed approach has better performance than
conventional soft handoff scheme.
Paper 3.7.1.3
Enhanced Soft Handover Algorithms for UMTS System
Soft HandOver (SHO) is becoming quite important because of its suitability for CDMA based systems.Soft handover
promises better performance than hard handover.The two most well-known benefits are fade margin improvement and higher
uplink capacity, while the disadvantages include lower downlink capacity and more complex implementation.Proper design
of handover is one of the main challenges in mobile communications, since it has a grate impact on the system
performance and capacity.Whereas in hard handover a definite decision is made on whether to handover or not, in soft
handover a conditional decision is made based on the variety of parameters involving several base stations.This makes
the soft handover design and parameter optimisation even more complex.Several soft handover algorithms have been used
and proposed in IS-95 and CDMA-2000 respectively.In this paper we have proposed two new soft handover algorithms and
evaluated and compared their performances wi! th the existing algorithms.
Paper 3.7.1.4
Automatic Base Station Placement And Dimensioning for Mobile Network Planning
The conventional manual planning processes are insufficient to the task of designing future generation mobile networks
because more sophisticated services and high quality of service are demanded by the users.Moreover, as the competition
between mobile service providers is increased, economic factors become more and more important in mobile network
design.That is why automatic planning processes are strongly required.Among them, the automatic placement and
dimensioning of base stations (BS) are the most important issues.This paper studies the problem of automatic BS
placement and dimensioning (ABSPAD) that is essentially a combinatorial optimization problem with exponential
complexity.The problem becomes more difficult since many complicated constraints are involved, such as radio signal
coverage, system capacity, spectrum efficiency, and coordination requirements.Due to these difficulties, no practicable
solution has been presented yet.In consideration of the above-mentioned difficulties, an innovative approach for ABSPAD
is presented in this paper.A high efficient optimization strategy forms the core of ABSPAD, that determines the number
of BSs, their sites and configurations to achieve a high quality network.The proposed approach is comprehensive because
it respects all system requirements and takes the existing infrastructure into account.Further advantages include the
use of a versatile and adaptive objective function that makes this approach applicable on different levels of network
planning and able to use the expert experience.Moreover, a hierarchical approach is proposed in order to reduce the
algorithm complexity.
Paper 3.7.1.5
Impact of Mobile-Originated Short Message Service on the Digital Control Channel of
TDMA Systems
The Digital Control Channel (DCCH) is the primary backbone for providing paging, call-setup, broadcast and other control
messaging for voice services on the ANSI-136 TDMA system.The DCCH also provides two-way short messaging services
through the R-DATA transport mechanism.This two-way short messaging service (SMS) provides a limited data-service that
can be used for various applications such as telemetry, two-way alphanumeric messaging, and limited Wireless Application
Protocol (WAP) services.Since the DCCH is a limited resource whose primary purpose is to carry call setup and control
messages, it is important to understand how it responds to various levels of messaging traffic.This paper presents a
performance analysis of the mobile-originated short message service (MO-SMS) showing its impact on the performance of
the DCCH uplink.After an introduction, the paper begins by presenting an overview of the DCCH uplink, which is based on
a slotted-ALOHA type random access protocol [3].Section 3 presents the simulation testbed that was used to generate
the performance results.Section 4 presents performance results that include characterization of the DCCH random access
protocol to derive the optimum protocol parameter settings and the performance of several levels of MO-SMS traffic mixed
with two different levels of voice and downlink SMS traffic.Note that voice and downlink SMS traffic also contribute
towards the messages generated on the DCCH uplink and hence affect the performance of MO-SMS.It is shown that for a
medium and high level of voice traffic load in the network, the DCCH has sufficient capacity to transmit MO-SMS messages
up to a certain ! load.After reaching this critical load of traffic, the RACH performance starts degrading.The impact
of MO-SMS traffic on the performance of critical voice traffic related messages on the uplink is also shown.Section 5
concludes the paper.
Paper 3.7.2.1
Sigmoid-Basis Nonlinear Power Control Algorithm for Mobile Radio Systems
Speed of convergence and distributiveness are deterministic properties of a power control algorithm for its possible
usage in cellular radio systems.Most of the power control algorithms in literature have roots in numerical linear
algebra or linear control theory, and consequently are in linear form.This paper proposes a first order, fully
distributed and sigmoid-basis nonlinear power control algorithm.The advantage of using nonlinearity is in fast
convergence and robustness against Rayleigh fading.In comparison with linear distributed power control algorithm of
Foschini and Miljanic as a reference algorithm, convergence speed is significantly improved.Simple computer simulations
have verified the effectiveness of the proposed alghorithm.
Paper 3.7.2.2
a
Modification of Maximum Power Handoff with Timer (MPHT) algorithm in Cellular Mobile
Communications
In this investigation in addition to modeling the MPH and MPHT schemes in a more than two cell structure,three new
modification will be introduced and a comparison will be presented between them regarding mean number of HO, Otage
value, Delay distance, Ping-pong rate and number of target stations.2.In this research, four major non-predictive
handoff initiation methods (MPH, TB, ITB and HYS)will be introduced and by simulating them in a 10 cell structure,
variation of performance metrics according to changes in related parameters of each algorithm will be shown.Optimum
combination of hysteresis and threshold based will be presented.
Paper 3.7.2.3
b
New Handoff Initiation Algorithm
(Optimum Combination of Hysteresis & Threshold based methods)
For improving Handoff Initiation algorithm, in addition to joint reduction of all performance metrics, one must consider
the simplicity of the algorithm and utilization of existing measured values.So in this work in order to modify the
handoff initiation method, optimum combination of Hysteresis and Threshold based will be presented.All of the algorithms
have been simulated in a ten cell structure so that the effect of the adjacent cells can be taken into account.
Paper 3.7.2.4
Iterative Equalization and Decoding with Channel Shortening Filters for Space-Time
Wireless MIMO channels with multiple transmit and receive antennas provide enormous channel capacity and therefore are a
hot topic for future wireless systems which require high data rates.Space-Time Coded Modulation has been shown to
achieve a considerable fraction of this capacity.However, in frequency selective channels the equalization complexity
grows exponentially with the channel memory and the number of transmit antennas leading to practically inacceptable
complexity.This paper first discusses channel capacity for frequency selective MIMO channels.Then an approach is
described to reduce the complexity of the equalizer by filtering the received signal in order to shorten the effective
channel memory.We show that part of the loss in time diversity can be transformed to additional receive diversity.
Furthermore, we compensate for part of the performance loss due to channel shortening by using a turbo feedback from the
space-time decoder to the equalizer.
Paper 3.7.2.5
Mobile Stations Location with Heterogeneous Data
The paper considers the problem of positioning mobile stations (MSs) in the context of a hyperbolic locationing
technique standardized for GSM (Global System for Mobile communications) as Enhanced OTD (E-OTD).The method estimates
the MS location in two dimensions by processing at least two relative distance measurements between the MS and multiple
Base Transceiver Stations (BTSs); thus cannot be applied in those circumstances, like in indoor or in open rural areas,
where not enough BTSs are available for positioning.In such conditions alternative techniques able to estimate the MS
position by using all the available information, are needed.The paper presents an algorithm suitable for application
in these cases.Accuracy results obtained with simulations and general considerations on the geometrical conditioning
of the problem will be provided in the final paper.
Paper 3.7.3.1
Simulation Results of a Typical GSM Pico-cell System
In this paper, simulation results of a typical GSM pico-cell system under various scenarios are presented.The
simulation results are based on simulating a 3 overlapping pico-cell base station under one scenario and 4 overlapping
base stations with two of the base stations being co-channel in the second scenario.The results have been obtained
using a powerful system level motion simulator that models all aspects of a GSM system including call setup and
handover.The paper covers the following: 1.An introduction of pico-cell systems including deployment techniques,
planning and optimisation issues.2.The description of the simulator used to derive the results including input
parameters and system performance statistics such as call blocking rate.3.The description of the pico-cell system
models used in the simulator.4.The simulation results including the call blocking rate, handover statistics and
capacity.The results are presented for optimised and non-optimised settings of the relevant parameters.5.
Conclusions.
Paper 3.7.3.2
Novel Strategy for Call Admission Control
This paper proposes a novel strategy for call admission control (CAC) in mobile cellular networks, which is based on
statistics of the past systems behavior.This algorithm is an extension of conventional guard scheme (CGC) and
demonstrates improvements compared to CGC by reducing probability of new call blocking Pnb , increasing the total
carried traffic Tc , while the forced call termination probability Pfct is kept almost unchanged.These results are
confirmed via simulation.In fact, the proposed policy introduces variable threshold for guard channels and falls into
the class of fractional guard policies.Each cell builds cumulative statistics from its *experience* and accepts a new
call only when predetermined handoff failure probability is not exceeded.A great advantage of this scheme stems from
the fact that its generic form is independent of cellular network topology.
Paper 3.7.3.3
Performance Analysis of GSM Traffic Channel Capacity With(out) High Speed Circuit
Switched Data
Analytical techniques for the analysis of the traffic channel capacity in the Global System for Mobile (GSM)
Communications are studied in this paper.The results are represented for High Speed Circuit-Switched Data (HSCSD)
traffic channels co-existing with the voice traffic channels in a GSM cell.In a GSM system the base station has a
finite number of traffic channels, from which one voice terminal occupies one traffic channel.The admission priority
for voice services is higher than that of the HSCSD data.On the other hand, one HSCSD terminal can occupy multiple
number of channels if needed, provided that they are available.The HSCSD terminal will release its reserved traffic
channels only after the data transmission is completed.The presence of HSCSD services slightly increases the blocking
probability of the voice terminals.The results in this paper show the steady-state channel utilisation and blocking
probability of voice terminals under the constraints wh! ere voice terminals occupy one traffic channel at a time and
data terminals can occupy multiple number of traffic channels.The results show that for a defined acceptable voice
blocking probability, the overall channel utilisation increases with the higher number of HSCSD terminals allowed per
base station as well as with the higher number of channels allowed to be allocated for each HSCSD terminal.The traffic
channel utilisation also increases if the acceptable blocking probability for voice terminals is allowed to increase.
The analytical model represented herein is general.Therefore, the channel utilisation and the voice blocking
probability results are calculated both with and without the HSCSD traffic channels.These numerical cases can be
obtained by appropriate parameter setting from the same process model
Paper 3.7.3.4
Performance Evaluation of an AAL2 Link Transmission Scheme for Voice and Data Packets
in BS-BSC Links
An AAL2 link transmission scheme is considered as a promising bandwidth-efficient voice/data transmission method in
BS-BSC links of third generation radio access networks.To guarantee low delay requirement of voice traffic, voice delay
restriction methods are introduced in the AAL2 link transmission scheme.That is, a timer is used in the loading of voice
ATM cell payload for limiting cell packetization delay, and a voice/data ATM cell multiplexing scheme with prioity in
voice ATM cells is introduced in order to reduce queueing delay in a voice ATM cell multiplexing buffer.A mobile
voice/data input traffic model is introduced and the performance of the proposed AAL2 link transmission scheme is
evaluated in terms of average voice and data link delays, link efficiency, and ATM cell overhead ratio.
Paper 3.7.3.5
Suppress Multi -Access Interference Detector Based on Software Radio
In this paper, A novel receiver architecture of multi-user detection for direct-sequence spread-spectrum multiple-access
communication systems is considered.We focus on a dynamically programmable receiver or software radio, which uses the
technique of multi-user detection.In order to reduce the computationally complexity and use a unitied framework for
achieving the reconfigurature, we partition functionality into two core technologies FPGA and DSP.
Paper 3.7.4.1
Capacity Simulations and Analysis of cdma2000 Packet Data Services
The promise of the third generation wireless communication system is to provide the subscriber a wide variety of services
such as access to Internet over the packet data connection at high data rate up to 2 Mbps.In this paper, the
performances of cdma2000 packet data services are analyzed through simulation study.The simulation models and
methodology will be described in this paper.The radio resource management schemes to control the traffic on both forward
link and reverse link will be discussed.The performance in terms of throughput, delay and blocking rate for packet data
rates of 64 kbps, 144 kbps and 384 kbps in ITU channel models will be provided and analyzed.
Paper 3.7.4.2
Effects of Code Acquisition Design Parameters in the IMT-2000 System
This paper describes code acquisition design of the DS-CDMA receiver in IMT-2000 system.There are some parameters of
code acquisition design, such as searching window size, integration length and threshold etc..These parameters are
effect on the probability of detection and false alarm.The effects of design parameters are simulated, so the
comparisons are made in the AWGN and fading channel.The results presented show the relationship between design
parameters and the system performance
Paper 3.7.4.3
Fixed Network Design in Cellular Systems using Local Search Algorithms
Search techniques such as Genetic Algorithms, Simulated Annealing, Tabu Search and Random Walk Algorithms have been used
extensively for global optimization.This paper presents an experimental analysis of the performance of these algorithms
for the problem of designing the fixed portion of a cellular network.
Paper 3.7.4.4
A formal approach to modeling and performance analysis of shared channels
The third generation of mobile systems will be able to support a variety of mult imedia services, most of which produce
variable bit-rate and could profit of transfer on shared channels used in combination with dedicated channels.In this
work the system provided with shared channels and the traditional one relying only on CBR dedicated channels have been
modeled and compared in the hypotesis of scalabile MPEG4-like video source.The analysis and performance evaluation of
the two solutions have been carried out with TIPPtool,a software strongly based on formal techniques, which appears an
ideal framework where to model, check and numerically evaluate communication protocols and systems.
Paper 3.7.4.5
b
A New Method to Solve the Dropped Call in CDMA Cellular System
The dropped calls can result from shadowing and rapid signal loss in the mobile environment.The recovery procedure will
become more important when the cells shrink to accommodate an increasingly large demand for services.In this paper, a
new method that is named transparent reconnect procedure (TRP) is implemented to decrease dropped calls.In the
simulation of a typical cellular system, it is shown that the benefit comes at the expense of a slight increase (less
than %1) in blocked call percentage.
Paper 3.8.1.1
Up-link performance of the DQRUMA MAC protocol in a realistic indoor environment for
W-ATM networks.
The up-link performance of the DQRUMA MAC protocol in a realistic indoor environment for W-ATM networks in presented in
this work.The physical layer is based on multicarrier modulation scheme (OFDM with 16 carriers) with QPSK modulation on
each carrier has been chosen.It provides a 20Mb/s wireless link in a carrier frequency of 5.2 GHz.The Hidden Markov
Model (HMM) is used for modelling the physical layer of the system.This method reproduces the statistical behaviour of
the physical layer, in terms of error distribution, obtained by means of detailed physical layer simulations.In the
W-LLC layer the type-II Hybrid ARQ/FEC is applied in order to ensure reliable transmission under the worst channel
conditions.In the event of collision a capture model is used in order to improve the efficiency of the system.Mean
delay versus throughput for several conditions as well as the p.d.f.of the delay are presented in this abstract.
Paper 3.8.1.12
Mutual Coupling and Scattering Effects on Cellular CDMA Systems using Smart Antennas
Cell capacity in a CDMA (Code Division Multiple Access) communication system can be increased through the use of base
station antenna arrays and digital beamforming.One factor affecting system capacity is the electromagnetic behaviour of
antenna array structures, usually modeled by combining the radiation patterns of the individual antenna elements through
superposition.Often, the mutual coupling effects between antennas are ignored and since they affect the radiation
patterns of the array, the system cell capacity predictions are also affected.Unfortunately, most beampattern synthesis
models which use superposition do not take into account the effects of mutual coupling and thus potentially lead to less
accurate system performance predictions.Furthermore, other models which do consider mutual coupling tend to make
inapplicable assumptions, leading to counter-intuitive results.We also consider a scattering environment to make our
predictions more realistic.In this paper, we investigate the cell capacity predictions of different signal propagation
models, including those which consider mutual coupling effects.
Paper 3.8.1.15
Transmission Performance of Beam and Null Simultaneous Steering S/T-Equalizer
In broadband mobile communications, co-channel interference and inter-symbol interference as well as relatively large
propagation loss are the major problems to overcome.Joint Space-Time-Equalization (S/T-Equalization) is considered most
effective in solving these problems.Optimal performance can be achieved through two-dimensional (joint spatial and
temporal) optimization.Unfortunately, it is excessively complex in many cases and a reduced-complexity sub-optimal
S/T-Equalization technique is needed.This paper proposes a new S/T-Equalization technique that performs separated
S/T-signal processing with acceptable levels of complexity.An Adaptive Array Antenna (AAA) with a new beam-forming
algorithm is used for spatial equalization.The algorithm combines the concept of beam steering with that of null
steering; a sharp beam is steered towards the desired signal while nulls are steered towards interferers.For temporal
equalization, a conventional DDFSE-type e! qualizer is used.The proposed S/T-Equalizer is prototyped, and field tests
are conducted in the 5GHz frequency band to evaluate signal transmission performance.The results show that the
proposed S/T-Equalizer can achieve a BER less than 10-5 at most of the positions over the entire measurement course in
suburban area.It is confirmed that the proposed S/T-Equalizer can reduce ISI effects while maintaining reasonable
signal strength, thereby improving BER performance.
Paper 3.8.1.17
Validation of Handset Antenna Test Methods
In this work some investigations of a test method for validating mobile handset proposed by Telia has been made.Telia
Research has made a special measuring setup in a room with metallic reflectors to mimic the fading and distribution of
incoming fields in a real radio environment.Test results of 10 commercially available GSM handsets measured in the Telia
test setup has been compared with measurements of the power, based on 3D radiation pattern measurements performed in an
anechoic room.Comparing just the transmitted power or efficiency of the 10 tested phones with the Telia test results a
rather large deviation was observed.The principal difference between the measurement methods is the radio environment.
This difference has been investigated in this paper by performing 3D radio environment measurements in Telias test room.
Paper 3.8.1.18
Sensitivity Analysis of Compact Antenna Arrays with Maximal Ratio Combining
This paper presents the average error probability performance of a compact space diversity receiver for the reception of
binary coherent Phase-Shift-Keying (PSK) signals through a correlated Nakagami fading channel.The analytical expression
of the average Bit-error-rate (BER) is derived as the function of the covariance matrix of the multipath component
signals at the antenna elements.Also, the closed form expression for the spatial cross-correlation is obtained under a
Gaussian angular power profile assumption, taking account of the mutual coupling between antenna elements.The
sensitivity of the error probability performance to the antenna array spacing, mutual coupling, and the operating
environment (fading parameter, angular spread and mean angle-of-arrival) is illustrated.
Paper 3.8.1.19
Simultaneous Characterisation of Multi-element Transmit, Receive Diversity Systems in
the UMTS Band
3 element transmit (at BS) by 4 element receive (at portable unit) antenna sysstems have been investigated at 2Ghz.Two
sets of antenna system have been test a tradtional space deiversity system and a polarsaisation diversity system.The BS
antennas had 15dBi gain while the outdoor portable unit had 8dBi gain.The indoor unit antennas where sleve dipoles.The
application is portable units for both fixed and postable applications, where the postable unit is palced either on
roof, at outside-wall or indoors Simulatenous sounding of all 12 parrallel links has been perfomed using a Doppler offset
technique.The measuredment bandwidth is 8MHz (mainlobe).This allowed a range of just beyond 2km (0.4W PA) The data will
be proccede both for diversity effectivenes as well as parralellism (independant channels).The experiments in a
suburban area are fully completed while the experiments in urban area are still ongoing.
Paper 3.8.1.20
A pre-FFT Equalizer Design for Application to HIPERLAN/2
This paper proposes a Pre-FFT Equalizer Design for application to a HIPERLAN/2 compatible receiver.It is shown that the
proposed design is capable of operating under the same delay spread conditions as a conventional HIPERLAN/2 receiver but
also facilitates the use of the optional short guard interval allowed by HIPERLAN/2.Use of this short guard interval
increases the transmission efficiency of the OFDM system by around 10%
Paper 3.8.1.22
Spreading Sequence Sets with Zero Correlation Zone
A general class of sequences with zero correlation zone (ZCZ) property is presented.The construction method is based on
mutually orthogonal complementary sets.The sequence sets can be used in quasi-synchronous CDMA systems to eliminate
cochannel and multipath interference.
Paper 3.8.1.23
Tracking of Time-Frequency Misalignments in 2D-Pilot-Symbol-Aided Coherent OFDM Systems
In this paper, a new time-frequency tracking approach for OFDM has been addressed.Two-Dimensional Pilot-Symbol Assisted
Modulation (2D-PSAM) is employed in coherent OFDM for channel estimation and it is based on inserting known symbols
spreaded out throught the 2D time-frequency grid.We show that these scattered symbols can also be employed to perform a
two-stage time and frequency synchronization.We broadely analyse the time tracking stage and, also, the performance of
the whole tracking scheme is shown.Maximum likelihood estimation has been derived for both time and frequency domains.
Also, a novel algorithm based on the phase shift at pilot sub-carriers has been proposed; it is robust against frequency
offsets and is suitable for use in dispersive channels.
Paper 3.8.1.24
On Optimum Stochastic Power Control: Solution by a Primal-Dual Algorithm
The purpose of this paper is to study optimal stochastic transmit power control in a wireless network.A motivation for
the study is given by a paucity of work on optimal stochastic power control.Previously, mainly stochastic approximation
techniques instead of stochastic optimization have been applied to the optimal power control problem.The paper suggests
a simple solution to optimal stochastic power control based on a primal dual algorithm, originally a method for
probabilistic constrained stochastic programming problems.Here the algorithm solves the problem of minimizing the sum
of transmit powers such that the no-outage probability exceeds a predetermined threshold.The framework of analysis is a
signal-to-noise-model of the uplink in a mobile network.
Paper 3.8.3.1
Channel Assignment in Cellular Networks without Channel Separation Constraints
This paper deals with the channel assignment problem in cellular systems.Usually this problem uses models that involve
defining and solving a set of channel separation constraints between pairs of base stations.These constraints are
derived by considering the potential interference at reception points within the service area of one base station from
an interfering signal radiating from another base station i.e.considers interference from a single source.We show that
significantly improved solutions can be obtained by directly considering the signal-to-interference ratio at the
reception points which takes into account interference from multiple sources.No channel separation constraints need be
used.Results will be presented for a local search algorithm on three realistic cellular networks.
Paper 3.8.3.2
The system performance analysis of link adaptation in Hiperlan/2
In this paper, we have studied the system performance of link adaptation for packet data services within the HIPERLAN/2
concept.The impact of processing of link quality measurements, update intervals, the shifting of the switch points and
link quality measurement inaccuracies are investigated.The simulation results show that for non-ideal link
adaptation,different processing method of link quality measurements may result in quite different system performance.
Longer update intervals only degrade the throughput and delay performance of the system slightly.It is also seen that
adding the link quality estimate inaccuracies may result in large decrease in throughput and delay performance compared
to ideal link adaptation.This decrease can however be improved if the link quality measures are filtered in a simple
way.
Paper 3.8.3.3
CLR Performance of VBR Traffic in Wireless ATM Access Networks
In this paper Cell Loss Ratio(CLR) performance of VBR(Variable Bit Rate) traffic in the wireless ATM access network which
consists of access node and wireless channel is evaluated.The impact of the bit error characteristics of a wireless link
in the wireless ATM access networks is focused.Possible error control architecture is also suggested to improve CLR
performance degradation caused by channel bit errors.Selective Repeat ARQ is considered as the conventional scheme for
VBR traffic and the Type I Hybrid ARQ is used as the recommended scheme.It is confirmed that CLR performance of the
network with recommended error control scheme is superior to that of network with conventional scheme.
Paper 3.8.3.4
An Optimum Rate/Power Allocation Scheme for the Downlink in Hybrid CDMA/TDMA System
In Internet access, portables are expected to send low bit-rate requests via uplink and receive high bit-rate
informations via downlink.Hence, to provide a reasonable wireless Internet access network, an efficient resource
allocation scheme for the downlink is necessary.In this paper, we propose a scheme that finds the optimum rate and power
allocations according to the channel fading condition seen at the beginning of each time slot.This algorithm should be
run for every time slot to continuously optimize the rate and power of the system.
Paper 3.8.3.5
Applying Splitting Slgorithms to Channel Allocation Problems -Parameter Selection
A Channel Allocation Problem (CAP) can be divided into smaller problems and be solved without losing much optimality
using splitting algorithms.However, this requires that adequate partitioning be applied to the problem.Some of the
considerations are discussed in this paper.Experimental results are presented for one-dimensional partitionings.
Paper 3.8.3.6
DS-CDMA MULTIUSER DETECTION OVER FADING CHANNELS
This paper is concerned with the reduction of both self interfernce due to multipath, and multiuser interfernce due to
multiple access for synchronous DS-CDMA communications over frequency-selective fading channels.The general structure of
these detectors consists of a bank of matched filters, a linear transformation that operates on the matched filter
outputs, and a set of threshold devices.The goal of the present work is related with a single sensor multiuser
detection providing a Multiuser + self Interference (MUI + SI) cancellation in order to improve the expected behavior of
classical schemes.This interfernce canceller exploits the well known Generalized Side Lobe Canceller (GSLC) scheme
based on the canonical presentation for the desired user linear detector.The orthogonality condition between both
components is imposed by proper design of the blocking matrix in terms of the interfernce subspace span.A complete
theorical analysis has been developed supported by several computer simulations over a multipath scenario to show the
feasibility of our proporsal.
Paper 3.8.3.7
A Prioritized Random Access with Discriminative Power Ramping Step Size
When multi-class services are provided in such random access channels, some discriminative treatments are needed.We
propose the random access method with discriminative power ramping step size to support the multi-class services.This
scheme can also be applied to CPCH because the first access of CPCH access is the same as the random access.We employ
this discriminative power-ramping-step-size scheme and analyze it with two different priority classes to get the total
throughput and the delay characteristics of each class.The analysis is done by means of equilibrium point analysis(EPA)
and computer simulation is used to examine the performance
Paper 3.8.3.8
An Adaptive Two-Stage Decorrelator for DS/CDMA
Recently, the authors presented a two-stage version of the decorrelating detector.It employs an additional detection
stage -- conditional quantization (CQ) on the lenear transformation outputs.This modification results in a significant
performance improvement of the decorrelator with a rather modest increase in complexity.Most importantly, the presence
of stronger users enhances the performance of weaker users in the CQ algorithm.In this paper, we develop an adaptive
version of this multiuser detector for time-variant channels using the zero-forcing algorithm.It is seen that the
proposed adaptive two-stage decorrelator is able to track the channel time-variant behavior automatically and
successfully.
Paper 3.8.3.9
Hierarchical Cell Structures with Adaptive Radio Resource Management
The paper deals with adaptive Radio Resource Management in hierarchical cell structures.Adaptive algorithms which
control the balancing of the offered traffic load among the hierarchical cell layers on the one hand and the division of
the available resources among the hierarchical cell layers on the other hand,are described and investigated by means of
computer simulations.Additionally Space Division Multiple Access (SDMA) is considered.
Paper 3.8.3.10
Capacity Comparison of Packet Options in cdma2000 with Various Power Control Methods
In the IS-2000 standard, packet data services could be provided by packet option P1(FCH,SCH) or P2(DCCH,SCH).The major
issue of using DCCH with DTX is the receiver's inability to distinguish between an erroneous frame and a cessation of
transmission.It leads to a problem in power control and causes a system capacity degradation.In this paper, we first
propose a robust power control method based on the measurement of the signal-to-noise ratios of the traffic channel and
power control sub-channel to solve the problem.Then, we compare the capacity of P1 and P2 by using link-level simulation
results of fraction forward transmit power with various power control methods.The MAC states transition is also taken
into account in the comparison.
Paper 3.8.3.12
Exploring Adaptive Turbo Coded modulation for Flat Fading Channels
In this paper, we consider different transmit side adaptation techniques for flat fading channels with transmit side
information when a turbo code is used as a channel code.
Paper 3.8.3.13
Dedicated Priority Function SEG for TD-CDMA Cellular System
In this paper, we propose a new channel allocation scheme for TD-CDMA cellular system.Our DCA scheme can allocate the
radio channel taking intercell interference and the service quality into account and it also supports asymmetric uplink
and downlink allocation.The simulation result proves that the proposed DCA scheme can reduce the blocking probability
compared with prior DCA schemes.
Paper 3.8.3.15
Mobile Assisted Handoff Based on Euclidean Distance Metric
It is important for mobile assisted handoff (MAHO) to accurately measure channel quality and report it to the serving
base station, which can help to avoid unnecessary handoffs and reduce handoff delay.We use a technique to measure
channel quality in terms of signal-to interference plus noise ratio (SINR) for the transmission of signals over fading
channels.The Euclidean distance (ED) metric, associated with the decoded information sequence or a suitable
modification thereof, is used as a channel quality measure.Simulations show that the averaged metric is a reliable
channel quality measure which remains consistent across different coded modulation schemes and at different mobile
speeds.The average scaled ED metric can be mapped to the SINR per symbol.The SINR estimate can be used not only for
MAHO but also for rate adaptation and power control.Simulation results show that the metric works well for MAHO,
reducing unnecessary handoffs and handoff delay.
Paper 3.8.3.17
A Study on Reducing Nonlinear Distortion in Multicarrier Systems
In this paper, we discuss on the realization of reduced peak power transmission for the multicarrier systems.Since the
signals have large amplitude fluctuations in conventional multicarrier systems, signals amplified by a nonlinear
amplifier are greatly distorted, resulting in severe performance degradation.In order to avoid this large amplitude
fluctuation, we propose a scheme for reducing the nonlinear distortion by using the set of the signal point series which
show low PMEPR (Peak to Mean Envelope Power Ratio) value.In this system, one symbol is transmitted with multicarriers
and the received signal is detected with maximum likelihood sequence detection.
Paper 3.8.3.18
Throughput Enhancement in TDMA through Carrier Interference Pulse Shaping
This paper introduces a novel TDMA scheme that provides enhanced throughput by employing carrier interference pulse
shaping (CIPS).At the transmitter, pulse shapes are created from the superposition of N carriers, which generates a
short mainlobe(pulse) in time.At the receiver, the pulse shape is broken down into its frequency components and
optimally recombined to create frequency diversity benefits.Simulations performed over a GSM channel model indicated
that the change in pulse shape from traditional GSM to CIPS results in up to a 100% increase in throughput.These results
were achieved without any loss in performance.The new TDMA scheme provides upto 300% increases in throughput when
compared to typical TDMA systems employing Nyquist pulse shaping.
Paper 3.8.3.19
Hybrid type-II ARQ/AMS supported by Channel Predictive Scheduling in a Multi-User
Scenario
We combine a Hybrid type-II ARQ/AMS (Adaptive Modulation System) with a Channel Predictive Scheduling system.Based on
the required bandwidth for each user, and their priorities, the scheduler allocates the time-slots to them, giving
priority to re-transmissions due to NAK-signals.Additionally, applying channel coding improves the error correction
capability of the system and provides robustness against the channel prediction errors, especially in situations where
there are considerable changes in the channel conditions during the prediction time interval.Moreover, the error
correction and modulation are done in an adaptive way, suitable for the time varying channel.
Paper 3.8.3.20
Performance Analysis of Fixed Cell Assignment in Broadband Wireless Networks
The analytic model and computer simulation in this paper evaluates performance in terms of the throughput of a dynamic
channel allocation method, called the Fixed Cell Assignment (FCA).The FCA emloys packet switched time division multiple
access transmission for the forward link in broadband (10 Mbit/s) wireless networks at the operating frequency 2 GHz.
Regarding the analytic model, the throughput of the base station is obtained using a Markovian queueing model at M/M/1/K
state for a single first-in-first-out (FIFO)buffer with finite capacity and the concept of the carrier-to-interference
ratio.If the buffer is full when a new packet arrives, the packet is blocked and cleared.The blocked packet should be
retransmitted from the mobile node.Using the power controlled interference model, the specific model for throughput is
obtained through the probability of the successful packet transmission in a time slot.Computer simulation shows the
relationship between the t! hroughput and the blockage probability.
Paper 3.8.3.21
An Investigation on Capacity versus Guard-Bands for the TDD Mode in UMTS
The UMTS terrestrial radio access (UTRA) is composed of two modes.The FDD mode, also referred to as UTRA--FDD, is
primarily used for the macro cell layer whereas the TDD mode (UTRA--TDD) might be used for 'hot spot' areas in the pico
cell layer.It can be shown that in the UTRA--TDD interface additional interference scenarios exist.These are MS-MS and
BS-BS interference which, however, can be eliminated by synchronising the network.Nevertheless, two networks run by
different operators cannot be assumed to be synchronised.Furthermore, if both operators use adjacent carriers and, for
example, the base stations are co--located, the adjacent channel interference (ACI) at the base stations cannot be
neglected.The interference leakage between two carriers results from receiver and transmitter imperfections.In
addition, the guard--band between adjacent carriers has an impact on ACI.By considering two different receiver filters
it is aimed to find an ideal carrier spacing in UTRA--TDD.On the one hand, the adjacent channel protection ACP is
increased if the guard--bands between carriers are increased.On the other hand, guard--bands result in unused radio
spectrum which results in waste of radio resources in a CDMA system.This paper aims at investigating this trade--off
with respect to capacity.
Paper 3.8.3.22
Fair Resource Management in Diverse Cellular Systems
This paper describes a hierarchical resource management structure which allows for fair allocation of resources in
distributed systems with diverse user requirements.The generic nature of the system allows it to be used with different
radio interfaces.The system uses techniques to ensure that different services and different sites meet defined quality
targets, irrespective of the operation of neighbouring sites or other service types.While this is traditionally
achieved through co-ordination between sites and networks, the proposed system allows an uncoordinated approach to be
taken, considerably simplifying the task of deploying multiple networks with small cells.
Paper 3.8.3.23
A New Estimation Scheme for Frequency and Timing Offsets in OFDM Systems
A multi-carrier scheme, such as orthogonal frequency division multiplexing (OFDM), is suitable for high data rate
transmission in wireless and wireline communications.However, it is more sensitive to frequency and timing offsets than
a single carrier scheme.Therefore, in this paper, we present a blind method to estimate frequency and timing offsets in
OFDM systems.First, we estimate frequency offset using an ambiguity function.After estimating the frequency offset,
we estimate timing offset using our suggested algorithm.We will show that these offsets can be estimated very
accurately using our method.Since our scheme doesn't need any pilot symbol in estimation, we can expect enhanced
channel efficiency in OFDM systems.In addition, our scheme has less complexity than the conventional joint estimation
methods because it separates the frequency and timing offset estimations.
Paper 3.8.3.26
Improving the Transmission Efficiency in the Mobile Communication Systems Using Turbo
Codes
This paper applies a variable rate scheme based on Rate Compatible Punctured Turbo (RCPT) codes in a mobile communication
system.The powerful error correcting code (Turbo code) with variable rate is suggested here to improve the transmission
efficiency and the performance of the system.A simultation is performed to predict the transmission efficiency in AWGN
and Rayleigh channels and the results are presented.
Paper 3.8.3.27
On the Capacity of Fading Channels
In our paper we explore the relationship between the ergodic fading channel capacity with transmitter and receiver
channel state information (CSI), the ergodic fading channel capacity with receiver CSI only, and the zero outage
capacity.In particular, we obtain general order relations for these different capacity definitions and also compare them
to the capacity of an additive white Gaussian noise channel (AWGN) channelwith the same average signal-to-noise ratio
(SNR).We determine conditions under which transmitter CSI significantly increases ergodic capacity, and we show that the
ergodic capacity of a fading channel can exceed the capacity of an AWGN channel with the same average SNR.We also
discuss the relative difference between the capacity of fading channels with transmitter and receiver CSI versus the
capacity with receiver CSI only.We finally give an example channel, the two-state Nakagami fading channel, where this
difference is relatively significant.
Paper 3.8.3.28
Comparison of Level Crossing Rate and Average Fade Duration of Nakagami and Rice
Fading Models with Mobile Channel Data
In order to characterize the dynamic behavior of the mobile fading channel, we need to have empirically-verified models
for important dynamic channel characteristics such as level crossing rate (LCR) and average fade duration (AFD).Among
the available fading models, Nakagami and Rice models have a special place.However, little effort has been made so far
in comparing the second-order statistics of these two models with real data.In this paper and based on measured data
in urban and suburban areas, we discuss the merits and limitations of the Nakagami and Rice models in describing the LCR
and the AFD of mobile channel data.
Paper 3.8.3.29
Considering Downlink Intermodulation Distortion in Switched Multibeam Antennas for
Cellular Radio Systems
Using multibeam array antennas at the base-station sites in a TDMA/FDMA cellular system increases the cellular capacity
on the expense of additional hardware.Hence, multicarrier amplifiers (MCPAs) are often suggested to reduce the number of
transmit amplifiers at the basestation.MCPAs will generate intermodulation products (IMP) at some power depending on the
linearization technique adopted.In this paper we analyze the combined application of multibeam antennas and MCPAs at the
basestation site.We derive a relation between the outage probability and the IMP level for different frequency reuse
factors and frequency trunkpool techniques for a cellular system with N multibeams in each cell sector.
Paper 3.8.3.30
Simulation of error process on mobile radio channels based on chaos equations
Accurate error process simulation is the natural and essential condition for an accurate choice of coding parameters
during communication network planning.Chaotic attractors have proved to be extremely useful devices during error
process definition, because of their pseudo-random appearance in spite of their totally deterministic nature.In this
paper the Lorenz attractor is used to generate bit streams and gap sequences calculating the position for two error
thresholds depending on target channel bit error rate (BER).An optimisation algorithm, oriented to match chaotic
simulator and target channel behaviour is introduced.Performance are very good for channels with BER values in the
order of 10-3 while lower error rates are only grossly approximated.Nonetheless the system is very simple to use after
the initial trainiing phase.
Paper 4.1.1.1
Building Shielding Loss Measurements and Modelling at the 5 GHz band
The propagation from satellite- to indoor systems is assessed.Focus is on buil- ding shielding loss measurements carried
out at the 5.1 GHz band in an office building.A helicopter was used to emulate the satellite.The distance between the
transmitter and the receiver was obtained by means of a differential GPS equipment.Results are presented in diagrams
showing the building shielding loss dependence on elevation and azimuth angles.The measurement results are compared to a
model that predicts the shielding loss in the presence of a line of sight between the satellite and the building.It was
found that the model performs well unless at low elevation angles, where the shielding loss is mainly due to knife edge
diffraction on surrounding building tops.This effect is now included.
Paper 4.1.1.2
ENGINEERING ASPECTS AND PERFORMANCE EVALUATION OF A MULTI-SERVICE LOW EARTH ORBIT
Low earth orbit (LEO) satellite systems allow personal communications using small, lightweight, cellular-like portable
telephones.A broad range of services are provided by LEO systems including voice, data, image, fax and paging.Thanks
to their low altitudes, LEO satellites can experience lower propagation delay with lower power requirements and smaller
antennas than the geostationary (GEO) counterparts.However, more LEO satellites are needed for complete coverage of the
earth.Moreover, satellites are not stationary with respect to a fixed point on the earth and the visibility period of
each beam is small.This results in massive handovers in an inverse way to that occurred in the terrestrial cellular
network.The engineering aspects of the LEO mobile satellite communication systems are presented in this paper.These
include the required number of satellites, power requirements, system layout and mobility parameters, inter-satellite
links, inter-spot handover, et! c.A strategy is devised in order to guarantee the service quality requirements.The
strategy aims at minimising service dropping as well as achieving fairness in service quality perceived by users roaming
in nonoverlapping and overlapping regions usually found between the coverage areas of spotbeams.The prospect of
controlling the access to spotbeam channels based on the location of a mobile station (MS) relative to the region of
spotbeam overlaps is suggested.Then, a teletraffic model for the LEO satellites network when providing voice, data,
and paging services is developed.The model accommodates the mobility of spotbeams, the location of MSs relative to the
areas of spotbeam overlaps and the suggested channel access policy.Performance measures of interest are investigated
and numerical results are presented for nominal system parameters.
Paper 4.1.1.3
Improving Subscriber Position Location using a Hybrid Satellite-assisted and Pattern
Recognition Technique
Position location of mobile terminals is one of the key services for mobile network operators.A variety of services may
be offered, such as emergency-call assistance, fleet management, location-based value added services, navigation, stolen
vehicle monitoring, improved network management and differential billing.Today, network suppliers and research
institutes worldwide are trying to conclude on the integration of positioning techniques, that will fulfil related FCC-
and ETSI- localization requirements, without exaggerating on the network costs.Positioning methods have already been
developed by major European manufacturers yet none of them has been adopted in a cellular networking environment.In this
contribution a hybrid technique is presented and its performance and compliance with the related standards is evaluated.
Paper 4.1.1.4
Error Control for K- and Ka-Band Land Mobile Satellite Coomunications Systems
An error control analysis for the K- and Ka-band land mobile satellite communications channel is presented.The dominant
propagation effect at K- and Ka-band is signal shadowing caused by obstructions in the propagation path.Depending on the
mobile speed, shadow events may last for several seconds and will typically result in attenuations on the order of 20 -
30 dB relative to the mean signal level.Three basic approaches to error control for this channel are investigated: ARQ
only with no FEC coding, a Type I hybrid-ARQ scheme designed to minimize repeat requests due to {\em random} errors, and
a ``brute-force'' Type II hybrid-ARQ scheme designed to correct erasures caused by signal shadowing.Throughput
efficiency results for each of these approaches are compared over a variety of channel conditions.
Paper 4.1.1.5
Wideband Wave Propagation Measurements for Local Multipoint Distribution Systems
(LMDS) at 26 GHz
In this paper the results of a wideband measurement campaign in the inner city of Karlsruhe, Germany, are presented.The
measurements were performed using an existing LMDS system.Therefore, the results can be adopted one-to-one for planing
purposes.The measurement bandwidth is 27.5 MHz at center frequency of 26 GHz.The measurements were carried out for
two different base station heights with several terminal station positions.Thus, a large number of different
propagation scenarios were investigated such as Free Fresnel Zone (FFZ), Obstructed Fresnel Zone (OFZ), Obstructed Line
Of Sight (OLOS) and None Line Of Sight (NLOS).Furthermore, the influence of vegetation obstructing the Line Of Sight
(LOS) path was analyzed.
Paper 4.1.2.1
Role of PAF in a Multi-satellite CDMA based LEO Satellite System
The downlink of a LEO satellite communication system employing power controlled DS-CDMA andexploiting satellite diversity
is analyzed and its performance is computed on BER floor with coherent detection.Performance evaluated using QA method
has been thoroughly validated by means of extensive Monte-Carlo simulations.Effect of MAI (Multiple Access Interference)
on the performance has been investigated with PAF.The quantitative results tend to indicate that diversity improves the
system performance provided that optimal power control scheme is employed.A realistic Convolutional coding with
hard-decision decoding is assumed to obtain specific results.
Paper 4.1.2.2
Location-aware Long-lived Route Selection in Wireless Ad Hoc Networks
We propose a new scheme to derive a long-lived ad hoc route based on location information of nodes obtained from GPS
(Global Positioning System) and the radio transmission range.Our proposed scheme selects more stable routes than the
pure shortest path scheme, hence avoiding frequent route reconstructions.
Paper 4.1.2.3
Bayesian Bootstrap Filtering for Multiple Mobile Position Determination using LEO
Satellites
The specific problem addressed in this paper is that of estimating the positions of mobile transmitters as functions of
time using noisy measurements of various physical phenomenon related to the kinematic state (position, velocity and
acceleration) of the transmitters.The mobile transmitters could be (enemy or friendly) infantry, aircraft, or land
vehicles in a battlefield.We solve this problem with the Bayesian bootstrap filtering approach using suitable
constraints on the states.The proposed algorithm is quite capable of handling data drop-outs and outliers in an
automated manner, and in addition, imposing nonlinear kinematic constraints on the state estimates without destabilizing
the algorithm.
Paper 4.1.2.4
Adaptive Dynamic Channel Allocation Scheme for Spotbeam Handover in LEO Satellites
Frequent spotbeam handover in low earth orbit (LEO) satellite networks requires a technique to decrease handover
blocking probability.In this paper, an adaptive dynamice channel allocation (ADCA) algorithm is proposed, which
estimates the future handover blocking performance of a new call attempt based on the user location database in order to
decrease the handover blocking.By simulation, it is shown that the proposed ADCA scheme substantially decreases the
handover blocking probability.Since ADCA algorithm utilizes the user location information, performance evaluation shows
that this technique also outperforms other techniques in the nonuniform traffic pattern.
Paper 4.1.2.5
Performance Evaluation of Intersegment Handover Procedures in UMTS Scenario
In the paper, after a description of the main ISHO algorithms developed for UMTS and their implications in terms of
complexity, the performance in terms of propagation delay and HO loss probability, carried out through simulation, will
be presented and compared.For each of the considered procedures the maximum execution delay and the HO loss probability
have been calculated.They are important to set up the time-outs necessary to receive acknowledgement messages and to
find out the percentage of HO failures as a function of the maximum tolerable time duration.
Paper 4.1.3.1
Bluetooth-based Wireless Connectivity in a Vehicular Environment
The paper is concerned with the applicability of a Bluetooth-based wireless access system as an integral part of a
vehicle-based communication and information platform.The full paper will give an extensive overview of the application
of BT in a vehicular environment, including basic BT procedures concerning connection set-up, configuration and topology
of the BT network, authentication and security mechanisms and other important issues.As well, the vehicle-specific
requirements and limitations of the use of BT will be covered.Furthermore, a detailed proposal for the above mentioned
scenarios will be given, and based on this, several BT in-vehicle applications and also the application of BT for the
communication between vehicles and stationary facilities will be addressed.Detailed information about the use of
existing BT profiles and corresponding communication protocols will be provided.Since the current BT specification does
not cover all necessary protocols and profiles to enable several possible usage scenarios, appropriate proposals will be
made, which could be part of a Car Profile which will be defined by the BT Special Interest Group in the near future.
Paper 4.1.3.2
A New Approach to the Geometry of TOA Location
Typical time-based wireless location systems based on both TOA and TDOA employ lines-of-position (LOPs) that are not
linear.For TOA, the LOPs are defined by circles whereas the LOPs for TDOA are defined by hyperbolic lines.It was shown
by R.O.Scmidt that the LOPs for a TDOA system need not be hyperbolic and he derived an alternative geometry which placed
the mobile unit's position at the intersection of straight-line LOPs.In an analogous work, we show that the LOPs for TOA
location also need not be circles, but can be represented in a new geometry as straight-line LOPs.This can aid location
algorithms based both on geometrical interpretation and on statistical analysis.The new approach to the geometry can aid
location systems in TDMA cellular networks, for instance, by allowing them to employ the more simple linear LOPs into
their location algorithms.In this paper, the new geometry is developed and mathematically analyzed for its performance.
Paper 4.1.3.3
Wireless Communication System Architecture and Physical Layer Design for Airport
Surface Management
A wireless communication system is presented which is designed specifically to operate in an airport radio environment
and serve the communication needs of airline surface operations.The physical layer design, based on spread-spectrum
technology, is optimized using recent RF field measurements and statistical characterizations of an airport ramp
environment.The communication architecture is optimized based on a study of airline operations and communications.
Paper 4.1.3.4
Enhancing Authentication Mechanism with Mobile Agent in Mobile Communication System
Today, telecommunications service providers need facilitate the rapid introduction of new services and resolve the
problems how to use the services safely.In this paper, a new network platform is introduced based on mobile agent and
an authentication mechanism is presented based on zero knowledge proof in the mobile communication system.At last, an
instance system namely TTIS is submitted in this way.
Paper 4.1.3.5
Security Architecture for Wireless Residential Networks
Residential networking via wireless access is expected to have an exponential growth in the next few years.Not only are
residential networking technologies heterogeneous, the communicating devices that connect to them will also be very
different.The widely varying features and capabilities of the communicating devices introduces additional security
concerns.In addition to traditional security services such as privacy, authentication, message integrity,
non-repudiation, access-control, and availability, some of these devices need certain intermediate security services
like authorization, identification, and varying degrees or classes of security and privacy.The potential security
implications and interaction between security requirements and residential network/device limitations are unclear.
Wireless communication devices are expected to be mobile and have the additional requirement that they must consume as
little power as possible while performing computations ! for encrypting or decrypting data to conserve battery power.
Spectrum is scarce and security protocols should not have excessive overhead or several handshakes to provide security
services.Both these requirements are usually contrary to security services as they are implemented in wired networks.
This paper addresses these issues and provides a taxonomy of security services and a framework for their design in
residential networks.
Paper 4.1.4.1
On Performance of Switching Techniques for Integrated Services in CDMA Wireless Systems
In this paper, we study the system performance of different switching techniques for a CDMA wireless system supporting
integrated services with different traffic characteristics, Quality of Service (QoS) requirements, priorities and bit
rates.Our work aims to develop a novel Medium Access Control (MAC) protocol for integrated services where resource
allocation is done according to traffic load, QoS and traffic characteristics of users.The applications considered are
voice, video, short packet and web browsing applications with fractal traffic characteristics.The objective is to
optimize system parameters that are user power, data rates and switching parameters.Integration of circuit, random
access packet and burst switching techniques is evaluated.The choice of the optimal switching technique for the admitted
user based on the user's class characteristics and the ability to foresee the potential of admitting a new call and the
corresponding impact on the system is a first step towards that direction.
Paper 4.1.4.2
A Power-Saving Multicast Routing Scheme in 2-tier Hierarchical Mobile Ad-Hoc Networks
In this paper, to solve the power-saving problem about multicast in the mobile ad-hoc network, we propose a power-saving
multicast routing scheme in 2-tier hierarchical mobile ad-hoc networks.In the proposed scheme, each master terminal find
the slave terminals in the same multicast group from the nearest position, and make connections to the found slave
terminals until the channel of the master terminal is full.If there exist slave terminals those are connected to
multiple master terminal, the farther master terminal releases the connection.
Paper 4.1.4.3
AN EXPERT SYSTEM ARCHITECTURE FOR THE DESIGN OF LOCAL AREA NETWORKS
Computer networks, specially local area networks (LAN), have become an essential part of the backbone of the information
age we live in.Designing a LAN to be most suitable to a certain configuration and application is not a trivial task.A
long amount of decision making should be carried out in the design phase and a compromise between different solutions
is necessary.The large amount of data to be collected, the choice between different alternatives and the dynamic and
heuristic incorporate expert system dictate the use of solution approaches incorporate expert system techniques.The
cabling cost of the wired LANs can be as high as 40% of the whole installation cost.This economic projection has caused
a growing interest towards Wireless Local Area Networks (WLANs) that can offer protability, lower installation cost and
covering remote geographic locations.Expert systems presented a great help in formalizing the practical rules that used
in solving local area network design problems.By sorting rules and facts, metarules determine a prioritized sequence
of subproblems to be analyzed, based on the problem under consideration.An overview on the physical layer specifications
of wire and wireless local area networks (WLANs) is presented.The physical layer of the WLAN discussed the
implementation and suitability of both radio frequency (RF) and infrared (IR).In this work, different faces of both
wired and wireless local area network design problems are presented and analyzed.New rules that give much attention to
the choice of wired or wireless LANs are introduced and integrated with the conventional rules.Also, recent LAN
applications with different traffic types and optimum choice of LAN topology are presented in terms of the rules.All
these rules gave the answers to the rule-based expert system queries, which employed as an optimization methodology and
an extra evaluation criteria to select the best solution to the proposed practical implementation of the LAN design
problem.Our LAN design problem is a building of a faculty, which includes four floor.Each floor of the building is
different than the others in its requirements for: 1) the number of PCs terminals, 2) the topology of each floor and 3)
the traffic weight and type in each section of each floor.The final form of the LAN that covers the design e! xample is
a reflection of the suggested rules with the aid of repeaters and bridges for optimal connections.
Paper 4.1.4.4
Performance Analysis of a Handoff Scheme in Integrated Voice and Data Wireless
In this paper, we propose and analyze a handoff scheme in integrated voice and data mobile cellular radio systems with
priority reservation voice handoff procedure.A method of numerical analysis of the system performance is presented.
Blocking probabilities of originating voice calls, voice handoff requests, and data channel requests, forced termination
probability of voice handoff requests, average length of voice handoff requests and data channel requests, and average
transmission delay of data are evaluated.Forced termination probability of voice handoff request calls can be decreased
by increasing the number of reserved channels.There is no transmission failure of data except for the negligibly small
blocking probability because a data channel request can be transferred from a queue of one base station to another.
Paper 4.1.4.5
Delay Performance Analysis of Voice Traffic in a Cellular Wireless ATM Network
In [2-3], Raychaudhuri and Wilson introduce the Time Division Multiple Access with Dynamic Reservation (TDMA/DR) Medium
Access Control (MAC) protocol for handling multimedia services in Personal Communication Networks.An Enhanced TDMA/DR
MAC protocol is presented in [11,16-17,20] to support voice, compressed video and data.In this paper, we assess the
performance of voice transmission using this Enhanced MAC protocol by computer simulation and approximate analysis.To
our knowledge, with the exception of [17], there is no delay analysis of delay-sensitive traffic in a cellular wireless
ATM access network reported in the literature.
Paper 4.2.1.1
Interfacing to the On-Board Diagnostic System
On Board Diagnostic (OBD) systems are incorporated into the computers on-board new vehicles to monitor virtually every
component and system that can affect the performance of the vehicle.The second generation of OBD requirements, which is
known as OBD II, has been fully in effect since the 1996 model year.If a problem is detected, the OBD II system
illuminates a warning lamp on the vehicle instrument panel to alert the driver.The system also stores important
information about a detected malfunction so that a repair technician can accurately find the problem using a special OBD
II Scan Too.The vehicle owner does not normally have access to this information.The information contained in the
on-board computing systems of modern vehicles, using the OBDII standard, could be very beneficial to the owner/operator.
With today*s readily available computing resources, this information can be made available.This paper describes the
approach to developing such a system.This includes the requirements for both the hardware and software with results.
Paper 4.2.1.2
Vehicular Information BROadcasting Relay (VIBROR) Protocol for Inter-Vehicle
Communications
This paper presents Vehicular Information BROadcasting Relay (VIBROR) protocol to realize the multi-hop transmission
scheme for broadcasting information without any complex negotiation among vehicles.In this protocol each information
packet consists of some sub-packets.Each sub-packet has the source vehicle ID, birth time, number of hops, and payload
information.Each vehicle memorizes received packet (sub-packets of other vehicles) into receiving buffer.Received
sub-packets are sorted by priority (i.e.number of hop, delay, distance, etc.) in the receiving buffer.When a vehicle
transmits information, it assembles a packet.The vehicle includes its own information (sub-packet) in the packet, and
attaches some sub-packets that have higher priority in receiving buffer.Every vehicle do the scheme, information is
relayed.
Paper 4.2.1.3
Distributed Antenna System for Mass Tranist Communications
Proposed abstract for IEEE VTC 2000 Conference, Sept 24-28, 2000 Distributed Antenna System For Mass Transit
Communication This paper will present an overview of an antenna system designed to support communications between
underground subway trains and others users and thier central control stations.The antenna system design is based on a
leaky coaxial cable.The system is capable of providing simultaneous RF coverage in three bands (VHF, UHF and 800/900
MHz), self-monitoring and auto-reconfiguration in the event of a failure.The system has been installed, tested and has
been in operation for over 12 months.The paper will discuss the overall antenna system design and focus on numerous
system aspects that were cirtical in order to achieve successfully deployment: nature and peculiarities of the
underground propagating environment with different tunnel cross sections and materials, methods used to achieve a
specified level of RF coverage, issues associated with antenna cable installation, data communications with headends,
system testing and system fault tolerance and modes of reconfiguration.
Paper 4.2.1.4
An Anti-Car-Collision System Using GPS and 5.8GHz Inter-Vehicle Communicationat an
Off-Sight Intersection
The paper will introduce an effective anti-collison system combining DGPS (Differential Global Positioning System) and
Gyroscope, to map the present position, and wirelessly exchanging that information using a 5.8GHz inter-vehicle signal.
There has been numerous number of research works conducted to prevent collisions by exchanging the position and velocity
wirelessly between vehicles, using SS and radars.However, these methods are mainly conducted under the assumption of
use in highways where the drivers can see each other, and are totally neglecting the low-visibilty residential areas
where most of the accidents occur.Instead of using a millimeter frequency wave currently used in ITS for radars, the use
of a 5.8GHz frequency band is considered.This band is expected to be used in the future for inter-vehicle
communications and its diffracting characteristic is expected.Through experiments, the communication with a 5.8GHz
signal was successful in an off-sight intersection.Therefore the system was proven to be a valid first step for the
future of ITS.
Paper 4.2.1.5
Technical Evaluation of an Electronic Millimetric Pre-View Mirror
Technical Evaluation of an Electronic Millimetric Pre-View Mirror Since a few years, autonomous intelligent cruise
control (AICC) systems as well as anticollision radars have been developed and are currently sold by manufacturers.
These systems are working at microwave frequencies.CEPT in Europe has opened frequency bands at 60 and 76 GHz for
these applications.They use millimetric sources to generate radiofrequency power in these bands that are still a little
bit expensive since currently close to the state of the art.Thus, it seems interesting to use these necessary dedicated
components to develop systems supporting simultaneously several functions.This paper technically explores the
possibility of using anticollision devices to support simultaneously several functions and especially a vehicle to
vehicle high bandwidth communication link.Starting from this point, our selected application is to demonstrate that it
is possible to use such anticollision sensors to transmit video information from a front coach to following vehicles
along ! a platoon.Thus, it becomes realistic to share in real time, with all the vehicles along the platoon, the
optimal road perception of the front coach.This shared information consists in the obstacles detected by the AICC or
anticollision radar on board equipment as well as the scene viewed from an on board video camera
Paper 4.2.2.1
Real-Time Low Cost Passive Imaging System For Automotive Applications
The purpose of this contribution is to describe a passive millimeter wave camera for traffic supervision and control and
on-board obstacle detection.These applications require real-time operation as well as low-cost and compactness
achievements.This paper will describe this passive imaging system, the design of the quasi-optical focal plane and the
elementary direct detection noise adding active antennas.The specific digital thermal noise signal processing and the
final image processing will also be described.Finally, the first imaging results achieved at 52 GHz in an automotive
environment will be presented.
Paper 4.2.2.2
Positioning emergency calls along roads and motorways using dedicated cellular radio
For security reasons, many roads and motorways are already equipped with conventional emergency call phones (fixed
standard phones).These equipments are connected to an emergency call management center by an optical fiber distribution
network in order to receive, to position and to treat emergency and distress calls.However, this classical emergency
call phone system presents some disadvantages: slow response time and less efficiency use of emergency resources in
particular if a driver is seriously hurt.In the same time, operators of mobile communications networks offer emergency
assistance via 911 in U.S or 112 in Europe.This seems perfect for the driver in difficulty but has one major drawback,
callers usually cannot communicate with the appropriate managing center assistance.To overcome these difficulties we
propose to develop a dedicated (GSM) cellular network along the infrastructure.Its architecture is based on GSM
nano-repeaters installed in emergency phone boxes connected through the existing optical fiber to BTS (Base Transceiver
Station), BSC (Base Station Controller) and an MSC (Mobile Switching Center).Each nano-repeaters covers a micro-cell
only in the road infrastructure.This architecture has major advantages since it can also provide emergency warning
information to the incoming drivers and enable interoperability of all emergency services (fire brigades, ambulances,
police*.).This paper will firstly report on this architecture and then will focus in examining positioning methods
derived from the Global System for Mobile communication applied to the dedicated cellular radio network.
Paper 4.2.2.3
On-board Dynamics Failure Detection of the Two-motor-driven Electric Vehicle System
This paper presents a dynamic failure detection algorithm and its on-board implementation developed for the
two-motor-driven electric vehicle system.A fault detection filter is designed and a decision metric is newly devised
such that it can simultaneously detect and locate the dynamic failures of sudden pressure drops in the tires and sudden
torque reduction in the inverter-motor-paired actuators.The design and implementation procedure of the fault detection
filter is described together with the illustration of the experimental results.
Paper 4.2.2.4
A scalable OFDM-based modem for future DSRC applications
Future dedicated short range communication (DSRC) systems should be able to support a large variety of intelligent
transport system (ITS) services, going from low data rate to multimedia applications such as Electronic toll collection,
Route guidence, Down load road maps and In vehicle internet.Moreover, they should be reliable in the harsh mobile
environment, high speed, ready for future applications and importantly low cost.In this paper, we present a flexible
OFDM-based platform that shows interesting features for the next generation DSRC systems.
Paper 4.2.3.1
Evaluation of GPS availability for Train Positioning along a Railway Line
Studies show that performance of satellites based localisation processes are often down-rated in high-rise masked
environments such as railways environments.Experiments have shown that high and nearby obstacles bordering a railway
line fundamentally characterise the service availability.The paper will present our tool based on image processing and
a satellite prediction pass software.It determines whether satellites should be received or not regarding the close
environment.Propagation effects characteristics will be defined and included, based on experimental and computation
results.
Paper 4.2.3.2
Comparison of Current Solutions for the Provision of Voice Services to Passengers on
High Speed Trains
This paper examines the railway environment from the point of view of the provision of 2nd generation voice services.It
examines the radio environment including fading, Doppler, transients, and penetration loss into carriages, as well as
special situations such as cuttings and tunnels.The paper reports on the operation of the IS-95 and GSM voice services
at high speeds, both assuming track side base stations and non-track side base stations.The paper draws conclusions on
the different types of environment encountered both for conventional and high speed rail lines, and the effect these
factors have on the overall link budget.
Paper 4.2.3.3
Metro-North Railroad Telecommunications Infrastructure Project
MTA Metro-North Railroad (MTA MNR) is the second-largest commuter line in the United States, providing more than 200,000
customer trips each weekday and some 62,000,000 trips per year.MTA MNR has an existing voice and data communications
infrastructure consisting of older fiber optic equipment, copper cable plant and leased lines.The infrastructure is used
for voice and data transmission services that are central to the day-to-day operations of the Railroad.The existing
infrastructure has exceeded its useful service life, and in some cases reliability of certain network elements is poor.
To accommodate existing and projected future voice and data communications requirements a hybrid telecommunications
network has been engineered, with construction slated to commence in the second quarter of 2000.Combining SONET, ATM,
TDM, HDSL, DACSs, DLCs and other widely deployed technologies, the network design seeks to keep MNR in the middle of the
herd while building a scalable platform that will provide a migration path for the future.The paper will focus upon the
design process and the rationale behind decisions reached by the design team that led to the selection of the
technologies utilized in the hybrid network.
Paper 4.2.3.4
Potential Use of Near, Mid and Far Infrared Laser Diodes in Automotive LIDAR
Applications.
Laser Infrared Detection And Ranging (LIDAR) may be used in on-board automotive applications for monitoring the distance
to objects approaching the host vehicle and their relative velocities.The low total cost of equipping cars with LIDAR
systems has motivated their development for the automotive market.These systems aim at improving vehicle safety or
driving convenience with features such as Adaptive (also called Intelligent) Cruise Control (ACC or ICC), Collision
Warning / Collision Avoidance (CW/CA), pre-crash sensing, pedestrian detection, reversing aid, and blind zone checking.
A drawback of LIDAR technology common to all optical systems is performance degradation in adverse weather conditions,
the most severe of which is dense fog.Scattering attenuation through fog decreases at longer wavelengths, and
therefore a LIDAR system operating in the far IR should be more immune to fog than one operating in the near IR.On the
other hand there are several other! factors affecting the choice of wavelength for an on-board LIDAR system.These
include the reflectivity of typical targets, the cost of the system, and the maximum permissible laser light intensity
allowable for eye safety.We discuss these factors for the range 0.85-10 mm in light of the experimental results of the
study we conducted to assess the ability to detect painted car body panels and various reflectors with 850, 910, 1560,
5600 and 8100 nm LIDAR transceivers.
Paper 4.2.3.5
Modeling of Hybrid Electric Vehicles using Gyrator Theory: Application to Design
Modeling and design of advanced vehicles such as Hybrid Electric Vehicles (HEV) and More Electric Cars (MEC) are
challenging because of the presence of two power plants in the vehicle.For the modeling of such complex hybrid systems,
the gyrator theory has many advantages.The most important one is that the approach results in very simple models such
as an equivalent electrical circuit for both electrical and mechanical parts of the system.In this paper, after
presenting the gyrator theory generalized to electromechanical systems and some preliminaries to prove the existence of
gyrators in the power plants, the application to a representative HEV will be discussed.At last, the proposed method as
a modeling and design tool is compared to other techniques such as bond-graph.
Paper 4.2.4.1
Modeling and Control of a Hybrid Electric Vehicle
The hybrid electric vehicle (HEV) is acknowledged to be the only current technology capable of reducing vehicle
emissions and fuel consumption by a large amount in a short period of time.An HEV is an electric vehicle with an
auxiliary power unit, which is usually a small, conventional, internal combustion engine (ICE).The complexity of
control problems for these vehicles requires the examination of newer control techniques.However, developing these
control systems in a reasonable time period requires examining many different algorithms, quickly.To achieve this goal,
the capability to tie modeling, simulation and application closely together with advanced control techniques is needed.
This paper describes the modeling and simulation of a hybrid electric vehicle emphasizing the control of the system.
Simulation results are compared to actual data to actual vehicle data.
Paper 4.2.4.2
The Multisensor Tracking System with the Airborne Sensor to Mitigate the Effect of
Cross-Range Errors
In order to mitigate the effect of cross-range errors of pencil beams from different sensors, we propose the multisensor
tracking system consisting of the airborne and stationary sensor.Here the airborne sensor is an aircraft that carries a
phased array sensor and moves to observe the target.In the proposed system, the airborne sensor moves to keep the two
pencil beams against the target to be orthogonal and the effect of cross-range errors could be mitigated by combining
the measurements from two sensors.As the results of simulation, when cross-range errors are large or long
sensor-to-target distances, the proposed system shows good tracking quality as compared with conventional systems.
Paper 4.2.4.3
Mobile Location Estimation in Cellular Networks by Fuzzy Logic
In this paper, a fuzzy logic estimator is proposed for mobile positioning of direct sequence code division multiple
access (DS/CDMA) cellular system by using received signal strengths.In a DS/CDMA system, a mobile station continuously
measures the pilot signal strengths from its home and neighboring base stations.The list of the signal strengths is
transmitted to the serving mobile switching centre (MSC) periodically through its home BS.With the reported strengths,
the fuzzy estimator within the MSC can estimate the position of the mobile station in real time.Furthermore, both the
current and previous measurement data are used to improve the estimation accuracy since the MS location depends on its
movement pattern (such as movement trajectory).Numerical results are presented to demonstrate the performance of the
proposed fuzzy estimator.
Paper 4.3.1.1
Capacity Enhancement Using Intelligent Relay for Future Personal Communication Systems
The paper highlights the key beneftis of incorporating Intelligent Relaying (IR) within future personal communication
systems.IR is a technique that enables mobiles in a network to receive and re-transmit data from other mobiles,
allowing mobile-basestation connectivity to implemented via a number of short relay hops.This allows an overall
reduction in power levels, leading to a reduction of interference levels in the network, and a possible increase in
capacity.Simulations have shown average possible power savings of 21dB; it is intended to extend this analysis to a
W-CDMA network and calculate the possible capacity increase.
Paper 4.3.1.2
Adaptive Transmission Rate Control Scheme for ABR Services in the CBR and ABR Services
Integrated DS/CDMA Systems
This paper proposes an adaptive transmission rate control scheme for available bit rate (ABR) services in the constant
bit rate (CBR) and ABR services integrated direct sequence/code division multiple access (DS/CDMA) systems to minimize
the average message delay time for ABR services without degrading so much the quality of services (QoS) for CBR services.
In the proposed scheme, the bit rate for each ABR terminal is controlled according to the amount of remaining radio
resource, and inter-cell interference is autonomously reduced by limiting the maximum transmitter power for higher bit
rate transmission.Computer simulation confirms that the average message delay of the ABR services can be shorten at most
1/10 times in comparison to fixed transmission rate of 32 kbps without decreasing the QoS for the CBR services.
Paper 4.3.1.3
GPS and GIS Techniques for Efficient Resource Allocation and Protocol Modeling in
Wireless Networks
Disruption-free operation of wireless networks is extremely complicated due to the scarcity of resources, the inability
of a single wireless service to provide ubiquitous coverage or to meet the requirements of all applications, the harsh
radio propagation and channel characteristics, and the dynamic nature of the environment.This requires algorithms that
take into account a number of parameters that are usually modeled as random variables.Protocols and algorithms for
disruption free operation of wireless networks thus use probabilistic and statistical models for design and performance
evaluation.An alternative approach for a more efficient operation of this type of networks is to utilize Global
Positioning System (GPS) and geographic information system (GIS) technologies.Through the use of GPS receivers, the
locations of mobile resources are determined and are imported to a GIS where they are combined with other data to
analyze and recommend efficient operation ! strategies.GPS/GIS techniques can dynamically increase awareness of the
environment and resources that will reduce reliance on statistical models or improve them.This paper investigates the
issues related to the benefits of employing GPS/GIS techniques in wireless networks.In particular we address what
wireless network problems can be solved optimally by integrating GPS/GIS technologies into them.
Paper 4.3.1.4
Packet scheduling in SDMA based wireless networks
The paper deals with packet scheduling algorithms for SDMA based wireless cellular networks.Depending on the terminal's
positions and the capabilities of the antenna and signal processing system it is possible to receive or to transmit
simultaneously for more than one terminal.We develop, analyze and validate analytical models for performance evaluation
and dimensioning of wireless communication links with space division multiple access techniques.
Paper 4.3.1.5
Uplink Acquisition of Synchronisation Parameters in MC-CDMA Systems
This paper is concerned with time-frequency synchronisation parameters in the Uplink MC-CDMA Systems.The
synchronisation process is based on one training OFDM symbol time that permits us to carry out the different stages of
synchronisation that involve burst, frequency offset, and an initial channel estimation of the entering user in the Base
Station.Firstly, the time detection of the different user's frame (in asynchroneous mode) are detected using the
cross-correlation characteristiques of the different spreading codes used for each user, the spreading technique used is
a concatenate orthogonal Gold code.This technique permits the improvement of the cross -correlation characteristiques
in time domaine.Secondly, the training symbol has a range of carriers used for the frequency offset correction; on this
range even carriers transmit information , meantime the odd ones are empties, each user has a specific location of its
carriers offset-correction , and an equidistant separation position of others users within the training symbol
guaranteed the non overlapping structure.Finally, we proceed the initial channel estimation for each user thanks to the
help of pilots inserted in the training symbol, in such way that each user has its own equidistant pilot's position.
This mode of pilot insertion reduce the complexity at the base station when the process of distinguishing the different
pilot location of each user is in process.The present proporsal combine the CDMA insertion mode for different spreading
codes, and the SS-MC-MA as a technique used for the transmission of offset-correction sequences.
Paper 4.3.2.1
DRMA with Multiple Slots Reservation and Retransmission Algorithm using Exponential
Backoff Scheme
The dynamic reservation multiple access (DRMA) has been proposed to improve the spectrum efficiency in the integrated
traffic.In that protocol, it solves the fixed reservation overhead problem since every available slot can serve as a
set of reservation minislots.Though when a data terminal needs to transmit a data message that consists of multiple
packets, it could reserve only one slot by one successful minipacket transmission.Furthermore, it is difficult to set
appropriate permission probabilities of voice and data, since both voice and data terminals use the constant values.In
this paper, we propose the DRMA with multiple slots reservation as the proposed-1, and the DRMA with retransmission
algorithm using exponential backoff scheme as the proposed-2, to reduce the data message delay and keep the voice packet
loss probability low.By the computer simulations, we show that the proposed-1 and the proposed-2 reduce the data
message delay and keep the voice packe! t loss probability low compared to the conventional DRMA, and as a result, we
show that the combined proposed-1&2 DRMA has good performance under the integrated voice and data traffic.
Paper 4.3.2.2
Capture with Delay and Power Randomization in Spread-Spectrum CDMA Slotted ALOHA
System
Capture effect in spread-spectrum CDMA slotted ALOHA system is considered.Probability of capture with both delay and
power randomization factors is derived and compared with other capture models.We evaluate the system performance in
terms of effective throughput and average delay, and clarify the effect of the capture probability and the packet
transmission probability.
Paper 4.3.2.3
Maximum Packing Channel Assignment Algorithm in Multi-Rate Traffic Microcellular
Networks
Many Dynamic Channel Assignment (DCA) algorithms have been developed, however, all of these proposed algorithms are
targeted for single rate cellular networks.Up to now, very little research has been done for multi-rate cellular systems
that have integrated services, i.e., voice, data, video, etc.In this paper, we evaluate the performance of the Maximum
Packing (MP) algorithm with cluster channel reservation in integrated services cellular systems.Also, we proposed a
practical distributed DCA scheme that approaches closely the system capacity of the MP with cluster channel reservation
algorithm.The capacity increase due to the use of the cluster channel reservation strategy is significantly greater in
DCA strategies than in FCA, because in the DCA schemes the reserved channels are kept in a cluster pool.
Paper 4.3.2.4
Predictive Adaptive Loading for Hiperlan II
This paper introduces predictive adaptive loading as a viable performance tech- nique for OFDM-based wireless networks
where the ETSI standard Hiperlan II ser- ves a case-study.Standard adaptive loading does not perform well due to the
time varying nature of wireless channels.By predicting the channel state, the constellation sizes of the different
carriers can be optimized to significantly lower the overall error rate of system at transmission time.We derive robust
MMSE-based prediction filters and analyze their performance in terms of Mean Squared Error(MSE).Additionally, we study
the performance of predictive adaptive loading on time-varying channels and show that almost all gain can be achieved
with only 3 previous channel measurements.Concluding, we found that combining adaptive loading with channel prediction
is able to significantly lower the error rate of OFDM-based wireless networks operating on time-varying channels at low
implementation complexity.
Paper 4.3.2.5
A RADIO CHANNEL EMULATOR FOR WCDMA,BASED ON THE HIDDEN MARKOV MODEL (HMM)
The paper will describe a radio channel emulator for the UTRA-FDD mode, based on the Hidden Markov Model (HMM).Since a
statistical system behaviour is needed to train the HMM, off-line simulations have been made.The results between
simulated and emulated statistics will be presented.The use of emulation models implies a loss of accuracy with respect
to simulation models, but is adequate to operate in real time.Certainly, the main advantage of using HMM in the emulator
is the huge reduction in time, resources and effort with regard to a real simulation of the system.The emulator will
allow, in future works, for fast testing and comparison of several higher layer protocols and error control schemes.
Paper 4.3.3.1
The Impact of Front End LNA on Cellular CDMA System
Tower-mounted LNA is known for improving the cell site performance (reverse link range extension) in a rural environment.
A series of tests were performed at CDMA test cell site to study the benefit of tower-mounted LNA, the impact of the loss
of cables, and its applicability to all different environments.The slope and intercept of the drive route is measured to
characterize the testing environment.The performance of diversity is also studied.A spreadsheet for (propagation
parameters) noise figure model was also developed and compared with the test results.
Paper 4.3.3.2
Performance Comparison of the Radio Link Protocols of IEEE802.11a and HIPERLAN/2
Two wireless LAN standards are being developed on the 5 GHz band, namely IEEE802.11a and HIPERLAN/2.The physical layer
of both standards use OFDM as modulation and can provide several transmission modes with different data rates.The basic
medium access mechanism in IEEE802.11a is based on CSMA/CA, while HIPERLAN/2 uses centralized multiple access.The length
of the protocol data unit in IEEE802.11a is variable, while it is fixed with 54 bytes in HIPERLAN/2.To support reliable
transmissions Stop and Wait ARQ and Selective Repeat ARQ are adopted in IEEE802.11a and HIPERLAN/2, respectively.To
compare the data throughput of both standards two single IEEE802.11a and HIPERLAN/2 cells have been simulated in a radio
environment with large open space space and NLOS.This paper is intended to show the comparison results and to give the
reasons for the performance difference.
Paper 4.3.3.3
Adaptive Traffic Control Scheme in Hierarchically Structured CDMA Cellular Systems
Hierarchical Cell Structure(HCS) describes a system where at least two types of cells (e.g, macrocell and microcell)
operate one upon another.In this paper, we have proposed a traffic control mechanism for CDMA HCS, which dynamically
adapts to varying traffic environment by adaptively distributing traffic between macrocell and microcell.The proposed
scheme dynamically adjusts coverage area of microcell to maintain a required signal to interference ratio in both
microcell and macrocell.Performances were measured in terms of call blocking probability and call failure probability
by computer simulations.Performance improvements were significant especially when microcell is heavily loaded while
macrocell is lightly loaded.
Paper 4.3.3.4
Interference-plus-noise covariance matrix estimation for adaptive space-time
processing of DS/CDMA signals
The ideal minimum-variance-distortionless-response (MVDR) filter evaluated using the perfectly known covariance matrix of
the desired-signal-free input vector can be shown to be equivalent to the MVDR filter evaluated using the perfectly known
signal-present covariance matrix.This is not the case, however, for their estimated filter counterparts.In this paper,
we investigate alternative design methodologies to improve the signal-to-interference-plus-noise ratio (SINR) and the
bit-error-rate (BER) performance of the adaptive joint space-time MVDR and auxiliary-vector (AV) DS/CDMA receiver-filter
estimators under limited data record operating conditions.We derive close approximations of the probability density
function (pdf) of the output SINR of two sample-matrix-inversion (SMI) MVDR filter estimators: The first estimator is
evaluated using the sample-average estimate of the covariance matrix of the desired-signal-free received vector while the
second estimator is evaluated using the desired-signal-present sample-average covariance matrix estimate.The resulting
pdfs reveal that the use of the desired-signal-present covariance matrix estimate can lead to severe SINR and thus, BER
performance degradation, under limited data records.Motivated by the above observation we propose a simple supervised
algorithm to estimate and then subtract the desired transmission from the received vectors prior to the sample-average
estimation of the input covariance matrix.This way we obtain an estimate of the interference-plus-noise covariance
matrix which is then used to evaluate the MVDR and the AV filter estimators.Simulation results demonstrate that the use
of the proposed algorithm can significantly improve the BER performance of the MVDR and AV receivers.
Paper 4.3.3.5
An Iterative Heuristic Algorithm for Applied Channel Assignment
The irregularities of real networks can make solutions to conventional channel assignment problems inadequately
constrained.In conventional approaches, channel separation exclusions are the sole mechanism for constraining
interference in a network.These channel separation exclusions are in the form of a matrix of minimum allowed channel
separation values for all pairs of sectors.Such a constraint works well when cells are spaced on a hexagonal lattice and
the interference seen between two sectors depends primarily on the reuse distance and sector orientation.In networks
having highly irregular propagation and coverage characteristics, an attempt to limit the total interference due to
multiple assignments using channel separation exclusions can become ineffective.This paper describes an algorithm that
imposes a limit on the total interference in addition to conventional channel separation exclusions.The algorithm has
been used to automate frequency planning across GTE Wireless.The results of the algorithm are compared with algorithms
that address classical channel assignment problems on a benchmark data set using highly irregular propagation
characteristics.
Paper 4.3.4.1
Forward link capacity of coherent DS-CDMA and MC-CDMA
broadband packet wireless access in a multi-cell environment
This paper evaluates the forward link capacity of three types access schemes, SC/DS-CDMA, MC/DS-CDMA, and MC-CDMA, for
broadband transmission (over 100MHz) in a multi-cell environment by computer simulation taking into consideration
other-cell interference and site diversity effect.Then, a design is presented for an appropriate broadband packet
wireless access scheme that achieves maximum throughput.
Paper 4.3.4.2
A Power Control and Scheduling Concept for EGPRS
Both Power Control and Scheduling can be used to fulfill quality of service requirements.In this paper the two functions
are compared regarding energy use.It is shown that minimum energy use is achieved with a combination.A concept for
optimal channel utilization and power level is presented.Furthermore, the Interference Energy model is introduced.With
this model the concept can be extended to comprise minimum interference also.
Paper 4.3.4.3
Cellular Coverage for Efficient Transmission Performance in MBS
The work presented in this paper focus on the problem of cell coverage towards a definition of adequate antenna
configurations for a given type of propagation environment.Emphasis will be given to the coverage of squares and city
streets, which may consist of a concatenation of several cells with a length imposed by the antenna gain, transmitted
power and the receiver sensitivity, being the width imposed by the width of the propagation scenario.The main antenna
configuration used in this work is the one developed in the ACTS SAMBA project framework which was used in the field
trial measurements.Despite the good performance characteristics achieved with this antenna configuration, such as fairly
uniform power distribution throughout the cell and the possibility to control the time dispersion of the channel impulse
response, it allows movement freedom of the mobile terminal.This paper will present a thoroughly analysis of the most
critical propagation impairments in typical MBS scenarios focussing on power distribution and channel time dispersion
throughout the cell as benchmark parameters for the system performance evaluation and how these parameters affect the bit
error rate (BER).A radio propagation simulation tool is used to estimate those parameters within the cells and the
measurements performed during the SAMBA field trials measurement campaign will be used to validate the results.It will
be shown, by simulation and with measured data, that the deep fading problems arising from multipath propagation can be
reduced considerably using Maximum Ratio Combining space diversity technique and its direct impact on the BER.Moreover,
it will be shown how good the simulation results match the measured ones in complex scenarios.
Paper 4.3.4.4
Sensitivity of performance of SARP and HARP to traffic loading variations in a
hierarchical cellular system under non-uniform traffic distribution
In this paper, Separated Autonomous Reuse Partitioning (SARP) and Hierarchical Autonomous Reuse Partitioning (HARP)
schemes have been investigated thoroughly and applied to a hierarchical cellular system, which consists of 36 macrocells
and 27 microcells.Assuming that a total of 70 channels are available, it is found that 40 channels should be assigned to
the microcell layer in the SARP scheme while in the HARP scheme, the macrocell would ensure there are at least 40
channels available in the microcell before taking up the call.
Paper 4.3.4.5
Uplink and Downlink Capacity Evaluations of a Multi-tier CDMA Mobile Network Employing
Directional Handset Antennas
CDMA systems use universal frequency re-use and multiple-base-stations can co-operate to provide service to a handset.
This alters the common perspective of a cellular system as one in which a single base-station broadcasts 'outwards' over
the cell to one where multiple base-stations broadcast 'inwards' to the cell to assist the central base-station.In the
conventional case omni-directional handset antennas are required whereas for the CDMA case, directional antennas can be
used to gain access to the network.The purpose of this of this paper is to evaluate analytically the effect of using
directional handset antennas on the system performance of an IS-95 and an IMT-2000 CDMA cellular system.The link
capacity is evaluated for both omni-directional and directional handsets for both the uplink and downlink cases.
Soft-handoff, shadow losses and imperfect uplink power control are included in the analysis.The results demonstrate that
the spatial filtering provided by directional handsets has the potential to increase both uplink and downlink system
capacity when compared with conventional omni-directional handsets.
Paper 4.4.1.1
MAP Equalization for DQPSK in Multi-pass Demodulation
The proposed paper investigates the effect of pilot bits on the performance of a MAP equalizer for DQPSK modulation.
This study pertains to the ANSI-136 (DAMPS) system and its associated ANSI-641 ACELP vocoder and error control coding
scheme.In a multi-pass demodulation scheme, re-encoded bits can be interpreted as pilot bits for the purpose of
succeeding passes of demodulation.We present analysis and simulation results that explain the impact of pilot bits in
detail.We draw some interesting conclusions from this study: that an equalizer is useful even in a non-dispersive
channel, and that a better placement of coded bits can significantly boost performance.
Paper 4.4.1.2
Achieving Flexibility in a Viterbi Decoder DSP Coprocessor
This paper describes a Viterbi decoder that functions with a DSP and has the necessary flexibility which allows it to
decode nearly every of code in 3G and 2G cellular standards.In particular, we concentrate discussion on the many
problems that arise when designing several degrees of flexibility into such a decoder, and on our solutions to these
problems.This decoder has a throughput of 2.5 Mbps and operates on various constraint lengths, code rates, frame sizes
and puncturing definitions.Branch metric selection, address and state index generation, and traceback are three portions
presented in detail.
Paper 4.4.1.3
Analysis of Internal Data Width Requirements for SISO Decoding Modules
This paper studies the dynamic range of the forward path metrics, the backward path metrics, and the extrinsic
information within a soft-input soft-output (SISO) maximum a posteriori (MAP) decoding module for parallel concatenated
convolutional codes (PCCCs).Upper bounds on path metric differences and the extrinsic information are presented as
explicit functions of the inputs.These bounds are employed to determine the minimum internal data width for the
hardware implementation of the decoder.Simulations show that the analytic bounds on the dynamic ranges and the internal
data width are accurate and tight.
Paper 4.4.1.4
Iterative Channel Estimation for EGPRS
The Enhanced Data GSM Evolution (EDGE) standard will increase the data rates in a GSM system significantly.An 8-PSK
modulation scheme is proposed which is more sensitive to impairments in the transmission medium than GMSK modulation in
the GSM system.Channel estimation plays a crucial part on the receiving end to overcome those impairments.In this
extended abstract we investigate different iterative channel estimation (ICE) techniques.In order to reduce complexity
sub-optimum algorithms are addressed.Comparisons with the GSM system show that not all algorithms are suitable for the
EDGE system.Simulation results show that with ICE the BLER in EGPRS can be improved by almost 2 dB.
Paper 4.4.1.5
Blind multiuser detection in multipath CDMA channels with unknown correlated noise
In this paper we deal with the problem of blind multiuser detection for DS/CDMA systems operating over fading dispersive
channels and in the presence of additive gaussian noise with unknown correlation function.Such a problem has been
recently addressed in the open literature and solved by resorting to a receiver employing two well-separated antennas,
such that the noise is spatially uncorrelated.A new method is herein proposed, which enables blind multiuser detection
with just one antenna, and which is thus suited for implementation in mobile handset transceivers.Simulation results
confirm the effectiveness of the proposed technique.
Paper 4.4.2.1
Error Performance Analysis of Space-Time Codes
Space-time coding is a bandwidth and power efficient method of communication over fading channels that realizes the
benefits of multiple transmit antennas.This novel technique has attracted much attention recently.However, currently
the only analytical guide to the performance of space-time codes is an upper bound derived by Tarokh et.al., which could
be quite loose in many cases.In this paper, an exact pairwise error probability is derived for space-time codes
operating over fast Rayleigh fading channels.Based on this expression, an analytical estimate for bit error probability
is computed, taking into account dominant error events.Simulation results indicate that the estimates are of high
accuracy in a broad range of SNR.For comparison, upper bounds for space-time codes are also evaluated based on the
classical transfer function technique.
Paper 4.4.2.2
A Fixed Point Approach to Wideband Amplifier Compensation for IS-2000
The efficient operation of a linear power amplifier (LPA) often results in enhancing the LPA*s inherent nonlinear
behavior.This causes generation of co-channel and adjacent channel interference due to intermodulation distortion (IMD)
and spectral regrowth of the sidebands.These deleterious effects are of great concern in present second generation
cellular systems such as IS-95.However, an LPA*s nonlinear behavior will have an even greater impact in the new
wideband third generation cellular systems such as IS-2000.In this paper, a digital baseband predistorter based on the
*fixed point* approach (FPPD) is used to compensate the wideband LPA in an IS-2000 system.
Paper 4.4.2.3
Frame Synchronization of Turbo Coded Systems Using a
List-Synchronization Technique
This paper proposes a novel fast frame synchronization scheme for encoded data packets.The sync bits are placed in a
mid-amble and encoded as a part of the data sequence, using the error correction encoder to resolve time ambiguities.
The list synchronizer is consisted of a frame ynchronizer, which outputs an ordered list of few best estimates of frame
starting positions and a decoder.While decoding, the decoder makes the final decision about the frame starting position
by evaluating a fraction of the frame.This technique is applied for turbo code synchronization considering AWGN and
fading channel.The performance improvement over conventional synchronization techniques is explored via simulation.
Paper 4.4.2.4
Subspace Based Multiuser Detector Algorithms
In this paper, new Multiuser Detector algorithms are developed for very high speed wireless CDMA networks.In wireless
terrestrial channels required to support broadband applications like video and digital television, multipaths with long
delays might hamper the reception.This is in addition to the interference between multiple users with varying signal
strengths.However, the wireless terrestrial channel is sparse.The multiuser detector developed here is of the decision
feedback topology.In this paper, a subspace based approach is employed, on this decision feedback topology, to exploit
the sparseness of the wireless terrestrial channel as well as the difference in users' signal strengths.{\it Selective }
updating of forward detector taps and feedback detector taps (from other users) will be employed by the base station, in
the detection process.This algorithm results in superior convergence speed and lower steady state mean squared error.
Paper 4.4.2.5
Performance Analysis of a Narrowband Two-Signal Receiver Based on Joint Detection
n this paper we analyse the error probability of joint detection based on maximum likelyhood estimation for simultaneous
reception of two narrowband co-channel users.The main contribution herein is to present an exact derivation of the
error probability as well as an union bound.Performance results are presented for the Gaussian channel and the Rayleigh
fading channel considering multiple antennas.It is shown that, for joint detection using antenna diversity, the
performance degradation for both signals is negligible compared to the one-signal case, thus doubling the system
capacity.
Paper 4.4.3.1
Two-Dimensional Code Acquisition in Fixed Multipath Channels
Code acquisition using an antenna array is investigated in our paper.Given that delay and angular domains are resolvable
a two-dimensional code acquisition is carried out.A fixed multipath channel with L-paths is used.Two basic serial
search strategies are studied, namely an angle-delay search and a delay angle search.The channel has L adjacent paths in
either the delay or angular domains.Performance measures are analytically derived in terms of mean acquisition time for
each case.Results are finally compared and discussed.
Paper 4.4.3.2
Performance of Soft-Output Space-Time Equalization for EGPRS
The use of antenna arrays can help to combat co-channel interference (CCI) in wireless cellular systems.In
interference-limited scenarios, space-time filtering techniques may be competitive with respect to trellis-based
algorithms, because of the difficulty of accurately modelling the space-time characteristics of CCI.We investigate the
impact of the quality of the equalizer soft-output (reliability information on the coded bits) on the performance of a
diversity EGPRS receiver employing linear and decision-feedback semi-blind filtering techniques.The best results are
obtained with a soft-output derived from short-term statistics based on the distance from the finite alphabet.
Paper 4.4.3.3
Generalized RAKE Reception for Cancelling Interference from Multiple Base Stations
In code-division multiple-access (CDMA) systems such as IS-95, IS-2000, and W-CDMA, receiver performance is limited by
own-cell interference, other-cell interference, and thermal noise.Orthogonal spreading codes are used to minimize
own-cell interference, so that it only occurs when the channel is dispersive.Multipath time dispersion also introduces
coloration in the interference spectrum, for both own-cell and other-cell interference.The interference spectrum may be
further colored by the pulse shape.Considering the interference coloration due to a dispersive channel and the pulse
shape, the conventional RAKE receiver, designed based upon theory of matched filtering in additive white Gaussian
noise, is not optimal.In this paper, a generalized RAKE (G-RAKE) receiver structure is developed to suppress both
own-cell and other-cell interference.Interference suppression is based on accounting for the coloration introduced by
the dispersive channel.Multiple base station signals are considered, allowing for other-cell interference suppression as
well as the soft handoff scenario.The receiver structure consists of RAKE fingers with arbitrary placement and combining
weights that account for the interference correlation between fingers.The combining weights are derived based on a
maximum likelihood formulation, and the finger delays are chosen to maximize the signal-to-interference-plus-noise-ratio
(SINR).Performance is evaluated both semi-analytically and via simulation.It will be shown that the G-RAKE receiver
provides significant gains in both BER and FER performance.
Paper 4.4.3.4
Multiuser-Macrodiversity Detection in Rayleigh Fading Channels
In this paper, we present a performance analysis for the reverse link of a wireless DS-CDMA system that exploits
macrodiversity reception while adopting the maximum likelihood (ML) multiuser detector for the basic detection.To our
knowledge this is the first paper to provide an analytical treatment of the ML multiuser-macrodiversity detector in
Rayleigh fading channels with imperfect channel state information (CSI), and we have shown that this detector is capable
of reducing the bit error rate (BER) for many users by several orders of magnitude.
Paper 4.4.3.5
Generalized Principal Ratio Combining for Space-Time Codes in Slowly Fading Channels
We present a generalized version of principal ratio combining (PRC), which is a near-optimum detection scheme for
space-time codes in quasistatic flat fading environments.In PRC, the performance penalty increases as the number of
receive antennas increases.In the proposed scheme, receive antennas are optimally grouped by K, and the PRC detection
method is applied to each group.This shows a flexible tradeoff between performance and decoding complexity by choosing
the appropriate K.
Paper 4.4.4.1
Improved Single-User Detector for WCDMA Systems based on Griffiths' Algorithm
The usage of mobile Internet and other mobile data communications will require cellular mobile phone systems with
increased capacity.One group of methods that achieves this is receivers with Interference Cancellation (IC).Among
these receivers, the usage of Griffiths* algorithm to adapt the despreader filter is chosen in this paper for a more
detailed study.A number of problems related to the WCDMA standard and the fading radio channel are identified and a new
receiver structure is proposed to solve these problems.The convergence properties and the bit error rate of this
receiver are studied assuming perfectly known radio channels.
Paper 4.4.4.2
Multiuser Detection with Partial Information for Asynchronous CDMA-Based Radio Networks
We consider the problem of designing the base station receiver for a CDMA-based cellular radio network.In this paper we
suggest a new approach to interference suppression and combine it with group-oriented multiuser detection.The resulting
performance of the proposed receiver is evaluated as a function both of the channel parameters and of the side
information provided.
Paper 4.4.4.3
On the Potential of Multimode Antenna Diversity
Throughout the history of wireless communications spatial diversity has played an important role in improving the
communication quality.A recent and interesting alternative way of exploiting the spatial diversity is to employ a
biconical antenna that is capable of forming multiple beams by exciting higher order modes.The diversity gain when
using Maximum Ratio Combining (MRC) will be examined for the biconical antenna with varying number of modes.The
performance of the biconical antenna will also be compared to the performance of a traditional array of dipoles.
Furthermore, the performance of a communication system employing a vector RAKE receiver together with a biconical
antenna will be considered as well.
Paper 4.4.4.4
Highly Efficient Large-Domain Moment-Method Analysis and CAD of Radio-Frequency
Antennas Mounted on or Situated in Vehicles
Modern radio, wireless, and satellite communication and radar systems often involve vehicles.From the electromagnetic
point of view, these vehicles are antennas and scatterers consisting of metallic and dielectric parts of very complex
and different shapes.There is a lack of adequate numerical methods and methodologies for dealing with this most
challenging and extremely difficult general radiation/scattering electromagnetic problem with an engineering
effectiveness.This paper will present highly efficient numerically exact (rigorous) electromagnetic modeling of
vehicles at radio frequencies based on a large-domain (high-order expansion) method of moments.Extensive simulations on
a PC, for both analysis and CAD, will be presented for various antennas mounted on or situated in cars over a wide
range of frequencies - from practically dc to lower microwave frequencies.For each application, parts of the vehicle
that are of the most importance for the antenna-vehicle! electromagnetic coupling will be identified, along with the
level of necessary details in modeling.The effect of the glass for some automobile antenna designs will be
investigated.
Paper 4.4.4.5
Channel Precoding for pi/4-DQPSK and MSK over Frequency-Selective Slow Fading
This paper presents channel precoding schemes to combat intersymbol interference (ISI) over frequency-selective slow
fading channels in wireless communication systems using pi/4 differential quadrature phase shift keying (pi/4-DQPSK) or
minimum shift keying (MSK).Based on the dimension partitioning technique, the precoders predistort only the phase of
transmitted signals in the forward link to combat ISI, keeping the transmitted signal amplitude constant.The main
advantages of using the precoders include that 1)ISI-free transmission can be achieved without increasing the complexity
of portable unit receivers; 2)the stability of the precoders can be ensured, even in equalizing a non-minimum-phase
channel; 3)the envelope variations of transmitted signals are reduced such that non-linear power efficient amplifiers can
be used for precoded signals.
Paper 4.5.1.1
Combined Temporal and Spatial Filter Structures for CDMA Systems
CDMA systems are interference limited and therefore efficient interference management is necessary to enhance the
capacity of a CDMA system.In this paper, we consider combining two effective receiver based interference management
strategies: multiuser detection (temporal filtering) and receiver beamforming (spatial filtering).We formulate and
examine the performance of several two dimensional linear filter structures each of which are all based on minimum mean
squared error criteria, but differ in how the MMSE problems are defined in the temporal and spatial domains, i.e.,
jointly or in cascade.It is shown that while the joint optimum MMSE filter achieves the maximum signal-to-interference
ratio (SIR) among all possible matrix filters, the constrained optimum MMSE filter which results in a single temporal and
single spatial filter, outperforms all combined single-user/multiple-user approaches and cascaded optimization approaches
either uniformly or asymptotically.The constrained optimum MMSE filter is near-far resistant in all but very highly
loaded systems and enjoys low complexity.
Paper 4.5.1.2
Iterative Decoding and Demodulation of Differential Space-time Block Codes
A differential space-time block code (D-STBC) can be used to achieve transmit diversity without channel state information
in the receiver at a cost of 3 dB.D-STBC is shown to be a recursive code that can be realized by a trellis.It can
therefore be used as an inner code in a serial concatenated structure with an outer convolutional code and a random
interleaver.Iterative demodulation and decoding of the signal received through a single antenna results in additional
coding gain that makes up for the 3dB differential detection loss as well as loss of orthogonality of the STBC because of
the time-varying channel.
Paper 4.5.1.3
INTERFERENCE CANCELLATION WITH PERMUTATION TRELLIS CODES
We investigate the application of permutation modulation and coding to OFDM and frequency hopped spread spectrum, as
employed in wireless communications.Furthermore, previous work in permutation modulation/coding dealt only with block
codes, while we construct new trellis codes.We compare the results obtained with our previously published technique of
distance preserving mappings, to results that we obtained with Ungerboeck set partitioning.Finally, we present some
bounds and tables with the best codes obtained.
Paper 4.5.1.4
DS Code Acquisition in Slowly Fading Multi-path Channel
Two philosophies in DS code acqusition in fading multipath channel is considered.In the first one, probability of
detection is averaged over the fading and in the latter, mean acquisition time is averaged.The latter is suitable for
slowly fading channels.The advantage of selection fdiversity is seen in fading multipath channel.The results are
compared to a static channel, and significant differences in operation are shown.
Paper 4.5.1.5
Co-channel Interference Ordered Statistics in Mobile Radio Systems with
Sectorized-Antennas and Beamforming
Co-channel interference (CCI) is a major impairment in mobile radio systems.An effective method to improve the capacity
of these systems is to employ techniques that reduce and/or cancel CCI, like beamforming and multiuser detection.The
latter is effective only for a small number of interferers.The dominance of a few co-channel interferers in mobile radio
systems has been shown in previous work.In this paper, we investigate the effects of cell sectorization and down-link
beamforming on relative interferer strengths by means of system-level simulations.We relate these results with the
gains obtained by a CCI cancelling receiver in an IS-136 down-link by means of link-level simulations.Cell sectorization
reduces the number of co-channel interferers in the first tier of co-channel cells, thereby reducing the number of strong
co-channel interferers.Down-link beamforming also adds to the disparity of co-channel interferer powers due to
transmission in directed narrow beams.
Paper 4.5.2.1
Bit Error Probability of M-ary Quadrature Amplitude Modulation
Wireless multimedia communication systems require bandwidth efficient digital modulation schemes because the available
frequency spectrum is limited.M-ary quadrature amplitude modulation (QAM) is an attractive technique to achieve high
rate transmission without increasing the bandwidth.For arbitrary M, an exact evaluation of bit error probability for
M-ary QAM is tedious to express the result in closed form.However, for any particular values of M an answer can be
obtained.For M=16 and 64, the bit error rate (BER) expressions are presented in [1],[2].But up to date the exact
general BER expression of M-ary square QAM has not been derived so far.In this paper, we derive and analyze a
generalized closed-form expression for the BER performance of M-ary square QAM with Gray code mapping in additive white
Gaussian noise (AWGN) channel.
Paper 4.5.2.2
The Capacity Analysis of SSB/BPSK-DS/CDMA with Successive Interference Canceller
When the SSB modulation using Hilbert transform is applied to BPSK-DS/CDMA, the statistical signal analysis about
multiple access interference is done.The analysis results show that the interference power due to multiple access
signals is increased twice in the SSB transmission with half channel bandwidth.Therefore the successive interference
cancellation(SIC) among the several interference cancellation methods which have been researched actively for the
capacity growth of DS/CDMA mobile communication system is combined with SSB/BPSK-DS/CDMA.Using the SSB/BPSK-DS/CDMA with
SIC, the increased other user interference can be eliminated, so that it is analyzed that the capacity can be increased
effectively.
Paper 4.5.2.3
Performance of a residue number system based DS-CDMA system over bursty communication
channels
This paper is concerned with the performance of a residue number system (RNS) based direct-sequence CDMA system over
bursty communication channels.Concatenated codes employing redundant RNS as inner codes and convolution codes as outer
codes are adopted to improve the system performance.An efficient interleaving method is designed to enhance the system
performance.The system is extensively simulated for different channel parameters for both multipath environment and for
bursty channel.The results show that the performance of the system is much better than similar systems when the SNR is
sufficiently high.
Paper 4.5.2.4
A self-calibration algorithm for an asynchronous CDMA-based antenna array
We present a new iterative calibration algorithm for an asynchronous CDMA-based antenna array in the presence of unknown
gain and phase errors.The algorithm is applicable to a non-uniform array, and does not require a prior knowledge of the
DOAs of the signals of any user.Most notable feature of our algorithm is that our approach does not require that the
number of source signals should be less than the number of antennas.To estimate more (correlated) signal directions
than the number of antennas, we use a subspace-based MUSIC type algorithm.The performance of the proposed algorithm is
verified through simulation for the case of a uniform circular array with six antennas separated by half a wavelength.
Paper 4.5.2.5
Multiuser Detection for Multi-Rate CDMA in Multi-Path Fading Channels
Wireless communication technology proceeds a brand new evolution.In the coming technology, the services are not only
focus on the traditional voice transmission, but multi-media aspects will definitely play important roles as the main
stream.The most significant difference comes from various data rates in all kinds of media, such as voice, image, and
video etc.Code division multiple access (CDMA) technique is a promising candidate for the coming third generation
communication systems, therefore, realizing the capability of multi-data-rate communication in CDMA systems is now an
important subject.Some previous papers have discussed multi-rate CDMA systems in AWGN channels.In this paper, we
analyze the operation of multi-rate CDMA systems in multi-ray multi-path fading channels, investigate the behavior of
different multi-rate schemes for multiuser detection, and support the minimum probability of error by optimal multiuser
detection design strategy as the benchmark of related researches.
Paper 4.5.3.1
An Efficient Carrier Frequency Offset Estimation Scheme for OFDM System
In this paper an efficient carrier frequency offset estimation scheme is proposed for an OFDM system.The proposed
scheme estimates frequency offset normalized by subcarrier spacing in two steps: tracking and acquisition steps.The
estimation range and variance of the estimation error are evaluated by simulation.The proposed scheme has a large
estimation range without degrading the variance of the estimation error.In this scheme the throughput efficiency and
computational complexity are improved by using only one pilot OFDM block.
Paper 4.5.3.2
A Re-Investigation of Scalar Quantization for Mobile Speech Transmission
We present a unified view of source and channel decoding supported by a priori knowledge.The complexity of our decoding
algorithms depends exponentially on the number of bits representing a quantized symbol.Therefore we investigate source
encoding by scalar quantization.With this concept more bits per dimension are required for source encoding because we
have to compensate for the loss in coding gain caused by the lower dimensionality.As a consequence, less redundancy can
be added by a channel code if the gross bit rate is kept constant.However, the lower dimensionality allows the efficient
use of unequal error protection and our proposed decoding techniques.We show the application of our joint source-channel
(de-)coding concepts to the IS-641 speech codec.
Paper 4.5.3.3
Joint Channel Tracking of Co-channel Signals for IS-136 Mobiles
Joint demodulation techniques have shown to be an effective method in mitigating co-channel interference for mobile
handsets with only a single receiver antenna.The performance of joint demodulation of co-channel signals depends heavily
on the ability to estimate the channel coefficients for the different users.In this paper, we describe some of the
potential issues and their possible solutions in tracking multiple user channels jointly.It is observed that channel
switching between the co-channel signals decreases the performance of the joint demodulation receiver greatly for medium
to high speed mobiles.When a channel switch occurs, the channels of the users are tracked well, but channels are
assigned to the wrong users.Consequently, from that point on all the detected symbols for a user of interest are
incorrect, since they belong to another user.It will be seen that this problem occurs especially for flat faded channels
with symbol aligned interference.To overcome this problem, the use of different channel tracking algorithms for
different users is proposed in this paper.The effect of using different adaptation parameters depending on the a priori
information (e.g.carrier-to-interference ratio, noise level and Doppler spread values) is discussed for the joint
tracking of co-channel signals.Using the proposed approaches, multi-user channel tracking is improved, consequently the
joint demodulation performance is restored.
Paper 4.5.3.4
Space-Time-Block-Coded OFDM Systems with Transmit Beamformers for High-Speed Indoor
Wireless Communications
A beamforming network is considered for the transmitter for the space-time-block-coded OFDM system in a high speed
TDMA/TDD QPSK indoor wireless network at 5.7 GHz.We find that the proposed system with a 24-beam antenna for the
coherent and differential detections can gain a 5 dB and 6 dB SNR improvements relative to the use of omnidirectional
antennas at the transmitter, respectively, at a BER of 10^-5.This improvement resulting from the transmit beamformer
allows for a reduction in the power required from the power amplifier, which in turn, enables the ``back-off'' necessary
to support the high peak-to-average ratios of OFDM.
Paper 4.5.3.5
Variable Length Equalisers for Broadband Mobile Systems
This research focuses on the performance of equalisers (in the context of 3rd Generation Systems) whose length varies
dynamically according to the channel conditions.This adaptation prevents the mobile terminal from using unnecessary long
filters when the channel conditions are good.This reduction in the filter length reduces the number of operations and
consequently the power consumption of the equaliser subsystem.The parameters of the algorithms used for the tap
adaptation (LMS,RLS) need also some adjustment after the equaliser structure has been modified, this issue is also
investigated.
Paper 4.5.4.1
Investigation of Two-Branch Transmit Diversity with Two-Branch Receive Diversity in
Micro Cellular Environments
In this paper two-branch MRC at the receiver together with two-branch transmit diversity is evaluated.The evaluation
was made with channel data measured in a microcell environment with slowly moving users holding a handset equipped with
two antennas.Furthermore this paper has analyzed the potential improvements of the downlink signal-to-noise-ratio (SNR)
which can be obtained by using a low complexity antenna system in a mobile handset for a UMTS system with transmit
diversity at the basestation.
Paper 4.5.4.2
Efficient Algorithm for Adjustment of Adaptive Predistorter in a Transmitter for OFDM
Signals
Recently adaptive predistortion of a nonlinear high power amplifier in the transmitter of a mobile communication system
has found great interest due to the fact that modulations characterized by a substantially varying envelope are
considered for future wireless systems.In particular, multicarrier OFDM modulations are considered as a method of radio
interface for wireless ATM and short range indoor access to wireless LANs.The paper is devoted to a simple and
efficient algorithm for adjustment of a look-up table predistorter compensating HPA nonlinearity when an OFDM signal is
transmitted.A simple modification of the gradient algorithm for amplitude and phase predistortions is proposed that
improves the rate of convergence of the adaptation algorithm and spectral purity on the output of the HPA.
Paper 4.5.4.3
Space-time front-ends for RAKE receivers in the FDD mode of UTRA
A unified and general vision of different space-time processors is presented.Many popular receivers can be
accomodated, like V-RAKE receivers, weighted V-RAKE, or spatial narrowband beamforming.By making appropriate
assumptions on the space/time characteristic of the interference it is possible to enhance the performance of the
receiver through spatial/temporal pre-processors.These receivers will be tested in the FDD mode of UTRA.
Paper 4.5.4.4
Iterative Detection for Rayleigh Space-Time Channels
In this paper we will consider the performance and convergence properties of several iterative implementations of linear
detectors for a multi-antenna Wideband Code Division Multiple Access (W-CDMA) system under the assumption of flat
Rayleigh fading.We investigate the successive relaxation iteration for both the decorrelator and MMSE filters.Using
random matrix theory to determine the asymptotic behavior of the eigenvalues of the iteration matrix we find accurate
bounds for the convergence properties of these methods.
Paper 4.5.4.5
PCC: Principal Components Combining for Dense Correlated Multipath Fading Environments
Spread spectrum transmissions and RAKE receivers are known to alleviate the effects of random fading.In the context of
future wideband/ultra-wideband systems, both estimation accuracy and receiver complexity are adversely affected when the
number of channel parameters increases.As an alternative to generalized selection combining schemes, which have received
a great deal of attention over the last couple of years, this work introduces a new class of diversity schemes that trade
off optimally diversity gain with receiver complexity.The basic idea is to exploit the information on the channel
statistics in selecting a linear mapping that reduces the channel order while minimizing the loss in terms of diversity
gain.We prove that the optimal linear mapping amounts to projecting the received data onto the channel's principal
components obtained by the eigenvectors of the channel correlation matrix corresponding to the Q strongest eigenvalues.
We then derive closed-form expressions for the average combined signal-to-noise ratio and the average symbol error rate
for various modulation schemes operating in dense Nakagami-m correlated multipath fading environments of practical
interest.
Paper 4.6.1.1
Access Control Algorithm for CDMA systems with Adaptive Antennas
A new access control algorithm for CDMA systems with adaptive array antennas is presented.In the algorithm, estimated
signal-to-interference-plus-noise power ratio (SINR) for each terminal is introduced which represents SINR at the output
of adaptive antennas under the assumption of a new call in service.If all of the estimated SINRs for new terminals and
active terminals are above the required SINR threshold, a new call is allowed to be in service.The simulation results
show that the system capacity of CDMA systems with 12-element adaptive antennas and proposed access algorithm is
increased by 40\% compared to the capacity of 12-sector CDMA system.
Paper 4.6.1.2
Transmit Diversity Schemes for Broadband Mobile Communication Systems
This paper considers the problem of incorporating the Alamouti transmit diversity technique in broadband wireless
communication systems operating in rapidly-varying high delay-spread channels.We propose two receiver processing
algorithms for mitigating the effects of Doppler spread in a mobile broadband system that uses the Alamouti encoding
scheme.The first algorithm is intended for OFDM and mitigates the effects of channel gain variation across the symbols
of a decoding pair.The second algorithm is intended for a frequency-domain equalized single-carrier system that employs
a simple technique for implementing the Alamouti encoding scheme.The second algorithm exploits a recently-presented
channel estimation scheme and is able to mitigate the effects of channel variations occurring within an FFT block.
Simulation results are presented to verify the effectiveness of the algorithms.
Paper 4.6.1.3
An adaptive VCT based handoff scheme for mobile base station in ATM network
We propose a new optimum handoff scheme to support network mobility.For efficient handoff involving several
connections, we introduce the concept of mobile Base Station(BS).Mobile BS forwards the end users handoff requests in
mobile platform to fixed networks BS.For the communication between mobile BS and BS in fixed network, signaling
protocols must be modified.In this work, we describes ATM signaling capabilities required for supporting this scheme
and present UNI/NNI protocol extensions.From the result of performance comparison of existing handoff rerouting schemes,
the handoff anticipation scheme has the smallest handoff delay.We propose an adaptive VCT handoff algorithm in the
consideration of prediction based routing scheme.Considering both mobile BS's moving speed and the number of active
connections in mobile BS, mobile BS will chose the different(or proper) size of tree.In shared cell structure, one BS
is connected with two MSCs.By adopting the shared cell structure, inter VCT handoff delay could be reduced.For the
performance evaluation of the proposed scheme, OPNET network simulator is used.According to the simulation results of
static and proposed adaptive VCT schemes in the circumstance of mobile network, inter VCT handoff frequency of new
proposed scheme is much smaller than that of previous VCT handoff scheme.Also, proposed scheme has the smaller handoff
delay.As the number of connections in mobile platform increase, and the moving speed of mobile platform becomes higher,
our scheme has better performance.
Paper 4.6.1.4
IN service management in IMT-2000 network
As the communication technology has been developed, it is necessary to provide the IN service in the mobile network as
well as the fixed network and many researches are in progress.In this paper we propose the network model to efficiently
provide IN services in the mobile network in the integration model of SCP and HLR.To manage IN services in the
integration model, we propose IN service management method using VLR and analyze the perfomance of IN service management.
This method is to download the IN service profiles that are saved in SCP to VLR and to decrease the connection to SCP
when the user requests the IN service.This method shows that the load of SCP/HLR is decreased and our method is better
than IMT-2000 in the aspect of IN service management
Paper 4.6.2.1
Channel Based Adaptive Resource Allocation at the MAC Layerin UMTS TD-CDMA Systems
This paper explores the idea of adaptively scheduling the allocation of the radio Resource Units (RUs), defined in terms
of slots and codes, at the MAC layer for the TD-CDMA radio interface of UMTS.The allocation algorithm which is proposed
tracks the fading levels of all RUs in order to make the best use of the available resources, within the contraints which
characterize the services required by the users.
Paper 4.6.2.2
The NLOS Error Mitigation Techniques For Position Location Using IS-95 CDMA Networks
The position location systems have become a hot issue over the past few years in wireless communication.It has valuable
applications in many areas such as public safety and enhanced emergency services, location sensitive billing, vehicle
and fleet management, and etc.So far, many people have thought of the Global Positioning System(GPS) as position
location system.But we can use the IS-95 Code Division Multiple Access(CDMA) networks of position location system.Two
systems considered for position location system in CDMA networks are direction finding and ranging.In this paper, we
have examined the position location system about direction finding and ranging system and analyzed the performance of
both systems.We also propose a position location system to make a mitigation the Non Line Of Site(NLOS) propagation
error in IS-95 CDMA networks.We will show that the proposed position location system improves the performance of
mitigation the NLOS ranging error.
Paper 4.6.2.3
Performance of 64 kbit/s Data Transmision with the ARQ Protocol of the DECT Standard
on Fading Channels
This paper presents the physical and DLC layers performance of a selective -repeat type-I hybrid ARQ protocol for the 64
kbit/s data transmission on a DECT radio interface over a Rayleigh fading or ITU indoor fading channel.Based on the LU7
standard for DECT and ISDN inter-working configuration, an extended stuty on the transmission delay is carried out.For
the simulation, the physical layer performance in terms of ABER and PER are given; at the DLC layer, the PER_ARQ
performance simulated both in the cases of the ideal and real feedback channels are presented.A theorical analysis is
carried out, in the case of ideal feedback, by using the Gilbert model and the ARQ procedure state transition matrix.a
good agreement has been found between the analytical and simulation results.
Paper 4.6.2.4
Complexity-Performance Trade-offs in Turbo Codes for IMT-2000
High demands for a variety of wideband services such as high-speed Internet access and compressed video/high quality
image transmission has resulted in the development of third generation cellular radio standards.To meet performance
requirements, powerful error control coding must be used, and turbo codes appear promising for high rate data services.
An 8-state constituent recursive systematic convolutional encoder with the (13,15) generator polynomial has been
recommended for high speed data services in IMT-DS subject to further investigation and evaluation.The goal of this
paper is to compare the performance of codes of different constraint lengths, combined with spread interleavers and
prime interleavers of various sizes, over log-normal fading channels.Constituent codes with more than 8 states, with
optimized minimum distance and multiplicities, are shown to generate better encoded sequences than the 8-state
constituent encoder, which translates to better performance.With simplifications of decoding algorithms and the speed
of ASICs, the increased complexity in decoding processes for larger-state codes over an 8-state code appears
insignificant.
Paper 4.6.2.5
A High Channel Efficiency Transceiver Based on Direct Access Frequency Synthesis
Technique
A novel high channel efficiency transceiver based on a fast acquisition frequency synthesizer has been designed.The
direct access frequency synthesis technique is applied and a simple memory look-up table is incorporated to expedite
channel acquisition.The technique simplifies the frequency control process in the transceiver and thus reduces the
channel switching time.As a result, the channel efficiency is improved.The proposed transceiver is ideal for
frequency hopping mobile communication applications.
Paper 4.6.3.1
ADAPTIVE QUANTIZATION FOR THIRD-GENERATION TDMA TRANSMITTERS
Pulse-amplitude modulation is used extensively in digital wireless systems, due to the needs for spectrally efficiency.
An example of such a system is the third-generation time-division multiple access (TDMA) system known as EDGE.In this
work, optimal quantization of pulse amplitude-modulated systems is analyzed and applied to an EDGE uplink transmitter.Of
particular interest is how uplink data is scaled prior to subsequent quantization as a result of digital-to-analog
conversion.Through analysis, two methods of quantization are presented - fixed and adaptive.Simulations are provided
which show that adaptive quantization provides a performance benefit over fixed methods in terms of baseband SNR.
Paper 4.6.3.2
Automatic Base Station Selection and Configuration in Mobile Networks
An important cellular network planning activities is to select a set of sites from a list of candidate sites which have
been identified as potential sites by marketing.The selected sites form the basis of a network which must satisfy
certain network requirements such as high area coverage and high traffic capacity but which minimize infrastructure
cost.The configuration of the selected base stations is also a complex problem and involves choosing between different
antenna types e.g.various directional or omnidirectional antennas, power control, tilt and azimuth.This work considers
the use of an optimization framework based on simulated annealing for base station selection and configuration, for
realistic sized networks.
Paper 4.6.3.3
Effects of power control errors and multipath fading
An analytical approach for the calculation of BER in a cellular CDMA system with imperfect power control is presented.
Power control is essential for such systems for good performance, however, perfect power control is hard to achieve in
real systems.Usually, imperfections in power control after despreading are modelled as a lognormal random variable.It
has been shown that, in a fading channel, the standard deviation of this variable is a function of the mobiles velocity
and of whether or not the mobile is communicating with the base station where the power is measured.In this work, we
show that when this fact is not taken into account the results obtained are too optimistic.We use the error statistics
to model the intercell interference and evaluate the impact of different mobiles velocity and number of resolvable paths
on the probability of error of the system.
Paper 4.6.3.4
Finding User Position Location using the Doppler Information in Satellite CDMA Systems
A new position location method based on the Doppler history is proposed to estimate the position of the mobile
transmitter for LEO communication satellites.The proposed method uses the code matched filtering to estimate the slant
range between the satellite and the mobile transmitter, and the coherent Doppler processing to localize the mobile in
the azimuth direction.We analyze the effect of the local oscillator drift, and compare the proposed method with the
known methods.Computer simulation indicates that our 2-D signal processing approach estimates the position of the
mobile trasmitter on Earth's surface, accurately.
Paper 4.6.3.5
An Integrated Approach for Performance Modeling and Evaluation of Soft Handoff in CDMA
Mobile Cellular Systems
In CDMA mobile cellular networks, wireless quality is improved by soft handoff techniques.However, it requires to hold
multiple channels of cells, which is likely to increase call blocking at wired channels.It is therefore necessary to
consider the intire system including the wired and wireless portions of CDMA mobile cellular systems for investigating
an effectiveness of the soft handoff.For this, we develop an analytical method to derive blocking and forced
termination probability as performance measures for wired channels, and the outage probability for wireless ones.
Through numerical examples, we evaluate the effects of the size of the soft handoff region.The effect of call control
methods is also shown to reduce total interference on wireless channels.
Paper 4.6.4.1
Potential Physical Layer Enhancements for AMR Speech over EDGE
Currently one of EDGE Phase II working areas is to develop a concept to provide speech with 8-PSK modulated EDGE traffic
channels.In this paper we outline a potential physical layer enhancement for TDMA systems via multiplexing two users
with possibly different data rates within one TDMA slot.As a practical example the transmission of voice with adaptive
multirate (AMR) speech codecs in GSM/ EDGE environments is considered.The presented method of user multiplexing allows
to increase the interleaving depth and improve radio-link budget.
Paper 4.6.4.2
UPLINK CAPACITY OF FFF W-CDMA MODE IN UMTS NETWORKS FOR MIXED SERVICES
A capacity evaluation of the FDD W-CDMA UTRA mode is performed for the uplink considering single and mixed services.Soft
Blocking, soft handover schemes and the influence of the dynamic range of the power amplifiers are taken into account in
the simulating environment.
Paper 4.6.4.3
A Traffic dispersion strategy in Fiber-optic multitier cellular system
In the microcellular system, the traffic is nonuniform and so, large amount of hot-spot cells are generated.In this
paper, we propose and analyze a new traffic dispersion strategy to prevent occurrence of hot-spot cells.This paper
assume fiber-optic multitier cellular system.In this fiber-optic radio system, all Channel Elements(CE) and call
processing hardwares are located in the Central Station(CS).The proposed strategy use this feature.If a macrocell is
to be a hot-spot cell, CEs of the microcell which has the minimum users are allocated to the macrocell and the microcell
is combined with neighboring microcell using simulcasting.If a microcell is out of channel, it can be solved using
group simulcasting.This strategy can be realized only in the fiber-optic cellular system.In this paper, we evaluated
the performance of this traffic dispersion strategy in fiber-optic multitier cellular system and could see that the
capacity of this system is increased and blocking probability is diminished.
Paper 4.6.4.4
Channel Estimation Using Short Training Sequences
The estimation of the impulse responses of time-variant mobile radio channels is a challenging issue in mobile
communication systems.For CDMA systems, it is generally assumed that the receiver knows the corresponding spreading
sequence.Therefore, this sequence can be used for channel estimation.Traditionally, channel estimation is achieved
by sending training sequences.This approach relies on a periodic transmission of long training sequences, making the
identification of channel feasible since both input and output signals are known during the transmission of this
sequence.Consequently, one must pay the price of using long training sequences with a significant reduction of channel
efficiency.This article proposes a maximum-likelihood channel response estimating method using a short training
sequence and the known spreading codes as training sequence, which will not result in significant reduction in net data
rate.
Paper 4.6.4.5
Joint Deployment of Macrocells and Microcells over Urban
Areas with Spatially Non-Uniform Traffic Distributions
In the third generation wireless communications systems, multi-tier cellular overlays will efficiently accomodate
exploding wireless subscribers.In this study, we investigate how the spatially non-uniform traffic distribution affect
on the design and the operation of multi-tier CDMA cellular overlays.To model service areas having spatially non-uniform
traffic distributions, we describe the service area by a grid of discrete block elements.Next, we propose a heuristic
algorithm for joint deployment of macrocells and microcells to accomodate the traffic load of the service area.To refect
the unequal traffic load of microcells, we derive a modified formula for the CDMA capacity.
Paper 4.7.1.1
Optimization of Power Management in a CDMA Radio Network
In a Code Division Multiple Access (CDMA) mobile wireless network, optimization of power management can enhance radio
link capacity and performance.Although power control has been studied intensively, power allocation and dynamic cell
breathing have not been given enough attention yet.The latter plays a more important role in optimizing an operational
CDMA system.This paper evaluates the CDMA capacity from a system point of view.The power allocation and dynamic cell
breathing are systematically studied.For a heavily loaded cell with double usage density of surrounding cells, when the
transmit power ratio of the center cell to adjacent cells changes 6 dB, the capacity of the whole cluster could
increase by 8%.The capacity of the center cell could enhance by 53%.Those demonstrate that optimization of power
allocation could improve the whole system capacity, especially relieve capacity shortage of hot traffic spot.Dynamic
cell breathing is the power management processing that a base station automatically adjusts pilot power percentage as
the cell loaded to ensure the balance between forward and reverse link.The cluster capacity could increase 43% when the
whole cluster pilot percentage changes from 15% to 5%.The center cell capacity could increase 31% when only the center
cell pilot percentage decreases from 15% to 5%.The capacity of a CDMA system can also be improved by optimizing the
power distribution through adjusting antenna beam-width, orientation and down-tilt.Commercially deployed CDMA system
demonstrates that optimization of power management is essential for a successful operational network.
Paper 4.7.1.2
SYSTEM LEVEL PERFORMANCE EVALUATION OF GPRS FOR VARIOUS TRAFFIC MODELS
In this paper, the system level performance of GPRS is evaluated under interference and coverage limited deployment
scenarios.The simulator is specifically designed to evaluate the pier to pier performance of the RLC/MAC layer.The
paper will address the following: 1.An overall description of GPRS including the code rates, RLC/MAC structure, burst
structure etc.2.A description of the simulator used to derive the results 3.Throughput, delay and coverage performance
results under a typical GSM environment and ETSI defined traffic models (e-mail, fleet management, railway applications
and SMS) 4.Conclusions
Paper 4.7.1.3
SYSTEM LEVEL PERFORMANCE EVALUATION OF EGPRS IN GSM MACRO-CELL ENVIRONMENTS
In this paper, the system level performance of EGPRS is evaluated under interference and coverage limited deployment
scenarios.The simulator is specifically designed to evaluate the pier to pier performance of the RLC/MAC layer.The
paper will address the following: 1.An overall description of EGPRS including, modulation code rates, RLC/MAC structure
and burst structure.2.A description of the simulator used to derive the results [1].3.Throughput, delay and coverage
performance results in GSM macro-cell environments.4.Conclusions
Paper 4.7.1.4
Performance Studies of Rate Matching for WCDMA Mobile Receiver
The third generation cellular system's main feature is the ability to offer flexible services simultaneously that were
not possible in the second generation system.However, one of the main problem in supporting such feature is the
degradation in the system performance due to the very different characteristics between each offered services.This
problem is solved in the 3GPP WCDMA system by implementing rate matching algorithm in the transport channel coding and
multiplexing mechanism.In this paper the WCDMA system performance optimization is studied by using rate matching
mechanism.
Paper 4.7.1.5
A Call Admission Algorithm with Optimal Power Allocation for Multi Class Traffic in
CDMA Systems
In this paper, we considered a call admission control algorithm for multiple types of services requiring different
SIRs(Signal to Interference Ratio) and transmission rates.With the expanding use of Internet, the forward link power
allocation is also becoming as important as the reverse link.Because of the asymmetry of data traffic between forward
and reverse links, an analysis on how much forward link capacity can be achieved in comparison with reverse link capacity
helps designing the system.First, the optimal power allocation that maximizes the capacity is considered.Then a simple
CAC algorithm is proposed and evaluated through simulation.
Paper 4.7.2.1
An Analysis of the 3-Stage Search Process in W-CDMA
This paper is concerned with the problem of acquiring the PN spreading sequence used by the transmitting base station
(BS) in a CDMA system.We consider the scenario where base stations are not synchronized.For this scenario, a three
stage acquisition and cell search procedure has been proposed and is now a part of the 3GPP WCDMA standard.We derive
analytical expressions for the probability of false lock and mean acquisition time for the three stage acquisition
process, and show how the analysis is useful for fine tuning the parameters of the search algorithm.We also show that
the analysis compares favoroubly with simulations,
Paper 4.7.2.2
Adaptive Path Selective Linear Multipath-Decorrelating Receiver for CDMA
Frequency-Selective Fading Channels
In frequency-selective fading CDMA channel, the concept of Multipath-Decorrelating (MD) is introduced to eliminate
Multiple Access Interference (MAI) prior to combining, thus preserving the benefits of multi-user detection and
multipath diversity reception.The MD receiver performance depends on the number of resolvable paths.The linear MD
receiver uses as many branches as the number of resolvable paths of the channel, which the transmitted signals pass
through, in order to improve the performance of the system.However, using all the resolvable paths of the channel in
the receiver makes the system very complicated since the dimension of the matrix to be inverted is large, depending on
the number of user (K) and resolvable paths (Np).As well known, the decorrelating detector results in noise
enhancement.It has been shown that, for a given number of users, the noise enhancement increases with the number of
resolvable paths.It seems that the only way to reduce both ! the complexity and noise enhancement is taking a subset of
the resolvable paths.But, in turn, this introduces multipath induced MAI that depends on the magnitude of the
eliminated paths.The first Mp < Np paths have been used and the increased MAI has been reduced using the antenna
diversity.The antenna diversity was used to regain the loss due to the multi-path induced MAI that overcame the
reduction in noise enhancement.In this work, we adopt a different approach.Rather than selecting the first Mp paths we
select a subset of the paths based on their magnitudes.The paths that fall in a range, determined by a threshold
relative to the strongest path, are retained.By doing so, we reduce the complexity and noise enhancement, even with
better performance, by keeping the degree of MAI much more less than the gain in noise enhancement.This method is more
flexible than the fixed path selection since it allows different number of paths for each user depending on their
channel ! characteristics.The performance improvement avoids the antenna diversity, which can be considered as another
factor that increases the system complexity.We provide simulation results that support our approach.
Paper 4.7.2.3
GPS-Based Message Broadcast for Adaptive Inter-Vehicle Communications
In this paper, we propose new broadcast protocols that make use of the global positioning system (GPS) information to
enhance the performance of broadcast service in Inter-Vehicle Communications (IVC).The ability to efficiently
broadcast messages is necessary for any communications in IVC (e.g.updating routing tables, etc) We propose two
algorithms that effectively reduce the number of re-broadcast message without affecting the number of hosts (vehicles)
that receive the broadcast.The simulation results show up to several hundred percentage of bandwidth utilization
improvement can be achieved by our proposed broadcast protocols.
Paper 4.7.2.4
Multi-Cell WCDMA Signal Processing Simulation
A highly detailed simulation model of NTT DoCoMo's W-CDMA third generation mobile system has been developed for system
performance analysis in presence of mobility and interference from multiple mobiles and base stations.The effects of
radio propagation, mobility and antenna and path diversity on performance of the signal processing algorithms and link
protocols in the receiver are evaluated for a single cell and then extended to multiple cells.This project has developed
a fast, scalable simulation model for the purpose of analyzing the transceiver design, data coding and framing.This
research track is leading towards full evaluation and design of interprotocol signaling methods to improve the
performance of 3G mobile Wireless Internet Access networks.Simultaneous evaluation and improvement of low level
transceiver design is also in progress.A new scalable simulation framework (SSF, the Scalable Simulation Framework) is
employed in this project to take advantage of the parallel computation as well as the easy expansion to the simulation of
high-layer protocol like TCP/IP.In this work, parallel computation is applied to the physical layer multiuser detection
as well as the multiple access interference generation in the multi-cell environment.
Paper 4.7.2.5
Enhanced Capacity Management for 2nd and 3rd Generation Cellular Networks
Cellular networks operators can not handle cases of traffic congestion with success.Especially in emergency situations,
where the access to mobile networks is needed, cellular networks usually fail to handle all call requests.In this paper
we discuss the congestion problem that arises because of the lack of resources.We propose a priority scheme in addition
to a dynamic bandwidth allocation mechanism that will enable an efficient capacity management and we compare its
performance.Moreover these thoughts will be proposed for the 3rd generation networks, i.e.UTRA.
Paper 4.7.3.1
Teletraffic Modelling and Performance Evaluation in Multilayer Cell Architecture
Multi-layer cell architecture sometimes referred as a Hierarchical Cell Structure (HCS) solution represents one of the
most efficient approaches to meet varying coverage, capacity and bandwidth demands in mobile cellular systems.However,
the performance of such system can be influenced by several factors.One of challenges in designing such a system is
adapting an efficient overflow policy and the provision of uniform GoS between the layers [1].In this paper we have
thoroughly investigated and analysed the performance of a two-layer cell architecture system with different overflow and
channel take-back policies.The simulation results are presented and compared with those of analytical model ling as in
[2, 3].The work is based on a comprehensive simulation model via discrete events simulation.Due to the abstraction
methodology employed in the simulation modelling, the model can be readily extended to embody more complex scenarios.
Paper 4.7.3.2
cdma2000 Reverse Link: Design and System performance
cdma2000 is being developed as a standard for the next generation wireless systems, supporting both voice and data.While
maintaining complete backward compatibility with TIA/EIA/IS-95 systems, cdma2000 will provide a number of service
enhancements.This paper analyzes the reverse link of the cdma2000 system, and reconciles the simulation results with
actual field test data.
Paper 4.7.3.3
Performance Enhancements for Release 2001 of the GSM/EDGE Radio Access Network
The GSM/EDGE Radio Access Network (GERAN) denotes the common evolution of GSM, TDMA/136 and EDGE towards providing full
third generation (3G) services and is currently being standardized in ETSI.In its first phase, EDGE will provide
enhanced data rates for best effort services using high level modulation.In the second phase of the standardization,
EDGE will provide real-time services over an all-IP Core Network (CN).Also, in release 2001 (R'01) of the standard,
performance enhancements will be included.These performance enhancements will be evaluated in a feasibility study during
this year.This paper will describe some initial results from the feasibility study.
Paper 4.7.3.4
Performance Optimization of Single Frequency Broadcast Systems in FDD-CDMA Cellular
Bands for Wireless Multimedia Services
We study the performance optimization of single frequency broadcast systems (SFBSs) spectrally underlaid in an FDD-CDMA
cellular network which operates in a High Frequency Band (HFB) for forward link and a Low Frequency Band (LFB) for
reverse link.The SFBSs coexist with the cellular network in the same geographic area and same frequency band.A
significant hindrance to SFBS performance is the power control employed in the cellular network, which increase
``near-far'' susceptibility at an SFBS receiver by increasing the potential range of received interference powers from
base stations (BSs) in the HFB and portables (PTs) in the LFB.We present a detailed model and a simulation analysis to
evaluate received bit-energy-to-noise ratio ($E_b/N_o$) demonstrating the susceptibility to the ``near-far'' problem in
the HFB and the LFB.In order to ensure acceptable performance in light of the ``near-far'' problem, we consider a family
of frequency allocation strategies exhibiting various levels of efficiency and complexity for use by the SFBSs: (1) Fixed
Channel Allocation (FCA), (2) Random Channel Allocation (RCA), and (3) Distance Based Channel Allocation (DBCA),
demonstrating a potential for significant performance improvement through the use of frequency allocation strategies.
Paper 4.7.3.5
Voice Enabled Request And Response For Mobile Devices Supporting WAP protocol
The Wireless Application Protocol (WAP) is the de-facto world standard for the presentation and delivery of wireless
information and telephony services on mobile phones and other wireless terminals.As soon as professionals step out of
the office, information needs and desires change.Wireless Internet subscribers want to use their handset to *surf the
Internet* and have access to the vast information available any time, anywhere.Instead of typing in the request using
the small keypad on the mobile device, it would be easier if the request can be entered through voice.More over the
stripped down information obtained from the request could be read out by the mobile device, instead of the user reading
it out from the small screen provided in the mobile device.This would greatly increase the usefulness and ease of
operation of the mobile device.All this can easily be incorporated in the mobile handsets with some minor changes to be
done in mobile handset, WAP proxy se! rver and WAP protocol.The paper tells how this can be done keeping in view the
constraints enforced by the mobile device hardware and current technologies.Some test results for the proposed model
will also be given in the paper.
Paper 4.7.4.1
Effects of Fading Correlation on Multiple Antenna Reception Mobile OFDM Systems
We address the issue of Maximum Ratio Combining (MRC) for mobile OFDM systems in correlated fading environments.MRC in
combination with OFDM is very appropriate for broadband mobile communication systems and efficiently combats the effects
of Rayleigh fading.However, the system performance crucially depends on the correlation between the received signals on
the different antennas since MRC exploits the signal fluctuations in the spatial domain.Since in physical systems it is
most likely to encounter correlated received signals it is important to evaluate the performance degradation due to this
correlated fading.The analysis presented in this paper is based on a generic channel model and we evaluate the
performance degradation due to correlated fading for different wave incidence scenarios.
Paper 4.7.4.2
A novel deregistration strategy for mobile networks
In this paper, a novel deregistration scheme -- lazy deregistration -- for mobile systems is proposed.In the proposed
scheme, instead of sending a registration cancellation message to the old Visitor Location Register (VLR) right after
each registration, the Home Location Register (HLR) keeps the identification of the mobile terminal (MT) in a list
associated with the old VLR.When the next registration from the old VLR arrives, the MT identifications maintained in
the list is sent to the old VLR along with the registration acknowledgement message.The old VLR deregisters those MTs
that have left its service area since the last registration from this VLR.Compared to the standard scheme deployed in
existing systems, the proposed scheme greatly reduces both the signaling traffic and the database access rate due to
deregistration.Compared to other proposed deregistration schemes, in our scheme, no valid records in the VLR are deleted
and no storage increase in the VLR is required.Moreover, the proposed scheme is easier to implement than the other
proposed schemes.
Paper 4.7.4.3
The Performance of the M-ary DS/CDMA Cellular
System over Rayleigh-Fading Channel with a Hybrid
EGC-SC Scheme
The BER performance of M-ary DS/CDMA communication systems armed with two different diversity combining schemes over
Rayleigh fading channel has been investigated.This includes the multipath equal gain combining (EGC) diversity, and the
combined EGC-SC scheme of which the N-th order multipath selection combining in combination with the 2-nd order equal
gain combining diversity is employed.The fading channel is a frequency selective discrete independent slowly fading
channel having L number of resolvable paths.The RAKE receiver structure with square law demodulation is used.The system
is operated in an asynchronous mode and perfect power control is assumed.The multiple access interference is modeled as
Gaussian.Three close form expressions to evaluate the BER performance for the two diversity schemes have been
respectively derived.The BER is expressed as a function of the average channel signal to noise ratio (SNR), the number
of active users (K) in the system and the order of diversity N.The analytical results has shown that for K=10 and SNR=10
dB the third order EGC-SC diversity is about 6 times superior to that of SC, whereas the EGC is about 3.1 times superior
to that of EGC-SC.The corresponding asymptotic BER of the EGC-SC is about 4.3 times superior to that the SC whereas the
EGC is about 2.1 times superior to that of the EGC-SC.Furthermore, the three close form expressions can also be applied
to other similar DS/CDMA systems with M-ary orthogonal modulation at higher transmission chip rate.
Paper 4.7.4.4
Capacity Comparison of Turbo and Convolutional Codes in Multi-cell DS-CDMA Systems
Turbo codes are investigated on the reverse link of multi-cell DS-CDMA systems over flat Rayleigh fading channels.Using
the Gaussian approximation for multiple-access interference, performance results of turbo codes are compared with that of
the commonly used convolutional codes in current DS-CDMA systems.Different frame sizes and processing gains which are
suitable for narrowband and wideband DS-CDMA systems are examined.Numerical results show that convolutional codes are
nearly optimal in narrowband DS-CDMA systems.In wide-band CDMA and large frame size, turbo codes provide considerable
capacity improvement over convolutional codes with similar decoding complexity.
Paper 4.7.4.5
Multi-antenna Wireless Base Stations in TD/CDMA Communications Systems
Wireless Base Stations (WBS) can be efficiently deployed to increase the coverage of a Fixed Base Station (FBS) and to
improve the SNIR of Mobile Stations (MS) located at the cell boundary.This paper focusses on multi-antenna transmission
techniques for the relay link between FBS and WBS in TD/CDMA based communications systems.Macro diversity, beamforming
and space-time coding techniques are discussed according to channel estimation overhead, computational effort, achievable
data rate and intra-/intercell interference contribution.Simulation results are presented based on a UTRA-TDD like
communications system and raytrace/stochastic channels.
Paper 4.8.1.1
Effect of the Cell Size and the Path Loss Model on the GSM Erlang Capacity for
Microcellular Environments
In this work, reuse efficiency in TDMA microcellular systems using frequency hopping,power control and discontinuous
transmission,is evaluated.In the literature, a two-slope propagation model for microcellular environments is widely
reported.The effects of the propagation model parameters on both the co-channel interference probability and on the
reuse efficiency are investigated.Also,capacity increase because of cell radius reduction combined with dynamic channel
assignment strategies (DCA) is evaluated.Our main contribution is to observe that the reuse factor depends closely on
the propagation model parameters and on the cell size.
Paper 4.8.1.2
Turbo-coded Error Control for Wireless ATM Networks
In this paper, turbo-coded error control scheme is analyzed and simulated for wireless ATM networks.The performance is
evaluated in terms of bit error probability and cell sync error rate.The wireless channel is modeled as a slow Rayleigh
fading channel.The simulation results are presented with the following parameters: 1) the number of iterations in the
decoding process, 2) interleaver length, and 3) standard deviation of shadowing.The comparative results are shown for
the optimal and suboptimal decoding algorithms used in the turbo decoding process.It is confirmed that the turbo coding
is very promising in controling the channel errors for wireless ATM networks.
Paper 4.8.1.4
Blind Decision Feedback Equalizer with Tracking Ability in severe Propagation
conditions
We propose here a blind Decison Feebdack Equalizer that learns in real time the non stationarity of the channel of
propagation.The time variation of the impulse response of the channel is represented by a markov model.The evolution
of the equalizer is done by the Non Stationary RLS algorithm tailored for tracking markovian time varying channels.
Since the Blind DFE has a tacking capacity, the BER is reduced in a blind equalization.Hence, it is not necessary to
transmit frequently a learning sequence.This can abviously increase the transmission rate espacially for severe
propagation conditions.
Paper 4.8.1.6
A Suitable Set Partitioning Method For MTCM With Biorthogonal Symbol Sets
The construction of biorthogonal sets and the distance property of the biorthogonal symbols is discussed in this paper,
based on which a suitable set partitioning method for MTCM with biorthogonal symbol sets is proposed.The generalized
set partitioning schemes have a reversed bintree structure.We note that we can simply utilize the difference vectors
to represent a set partitioning scheme with biorthogonal symbol sets.
Paper 4.8.1.7
Postdetection Diversity Receiver for DAPSK signal over the Rayleigh and Rician Fading
Channel
In this paper, we propose a postdetection diversity receiver for DAPSK and the performance of the proposed receiver is
analyzed theoretically over the Rayleigh and Rician fading channel.The proposed receiver is implemented based on the
maximal ratio combining technique.So, the proposed receiver can overcome the drawback of the conventional diversity
receiver based on the equal gain combining technique.In addition, by using the weighting factor calculated by optimum
decision boundary, the performance of the proposed receiver increases more significantly.
Paper 4.8.1.8
The Effect of Branch Correlation in Dual MRC, SC and SWC Diversity Systems
Space diversity combining systems require more than one antenna to receive signal and the antennae are usually spaced so
close together.This paper thus presents a performance analysis and comparison of the effect of branch correlation on
three popular combining schemes, namely, maximal ratio combining (MRC), selection combining (SC) and switched combining
(SWC)for noncoherent MFSK over Nakagami-m fading channel.Numerical results demonstrate that the error performance of
using MRC and SC are very similar when the branch correlation is high.
Paper 4.8.1.9
Multi-Channel (Blind) Equalization for TDMA Cellular Systems
Space-time processing using antenna arrays is a promising approach for improving quality, coverage, and capacity in
digital cellular communication systems.(Blind) adaptive multi-channel equalizer for decision feedback filter combined
with semi-blind channel estimation is proposed effectively to mitigate co-channel and intersymbol interference in a TDMA
cellular phone system such as GSM and IS-136 TDMA systems only using the training sequence of the desired user under time
varying channel situation.In our scheme, the channels are estimated using training sequence in every slots and used as
initial values for the proposed sub-optimal multi-user receiver to mitigate the slowly fading frequency selective
multipath channels and co-channel interference.
Paper 4.8.1.10
Analysis of iterative decoding for serial concatenated convolutional codes
Serial concatenated convolutional codes (SCCC) is another kind of turbo codes
and can get better performance than parallel concatenated convolutional codes
(PCCC). It has particular decoding algorithm different from PCCC. This paper
describes the our decoding procedure of SCCC in details, and shows the
simulations.
Paper 4.8.1.11
Transmit Diversity for Multicarrier CDMA
Transmit diversity is an effective technique to improve wireless communication performance.Recently, space-time codes
are proposed to get transmit diversity for narrowband systems.In this paper, we investigate space-time coding for
multicarrier CDMA systems.It is demonstrated that space-time coding can significantly improve the performance of
multicarrier CDMA in fading channels.Thus, combing multicarrier CDMA with transmit diversity using space-time coding is
a promising technique for multiuser, high-rate wireless communications.
Paper 4.8.1.12
The Adaptive Least Mean Square Algorithm Using several Step Size for Multiuser
Detection
The major limiting factor of the capacity of DS-CDMA system is the multiple access interference(MAI).Adaptive detectors
have been introduced to reduce the MAI.In this paper, we introduce a LMS algorithm with a modified step size for
adaptive filtering.An adaptive feedback constant step size in the LMS algorithm controls the convergence rate of the
filter coefficients but also determines the final excess mean-square error as compared to the optimal Weiner solution.
Since the convergence time is inversely proportional to step size, a large step size is often selected for fast
convergence.This selection, however, results in increased misadjustment or error residual.The proposed detector uses
the LMS algorithms with three different step size to reduce misadjustment and obtain fast convergence The advantages of
this detector are that convergence is fast , and that misadjustment is small.However this detector has a defect that
hardware complexity is increased.
Paper 4.8.1.13
SPACE-TIME MULTISTAGE PARALLEL INTERFERENCE CANCELLATION FOR CDMA
This paper introduces a space-time, multi-stage parallel interference cancellation scheme for code-division multiple
access (CDMA).The proposed scheme is based on the multistage, parallel interference cancellation (MPIC) [1-5] which is
a multi-path time process on a single antenna.Aware of the key to canceling the multiple access interference (MAI) for
the MPIC is the accuracy of the estimated MAI which largely depends on the bit error rate (BER), we propose to decrease
the BER by leveraging spatial diversity to increase the SNR through using multiple antennas.In single antenna case,
SNR is enhanced by multi-path diversity (equivalently frequency diversity) since the multi-path signals are
uncorrelated (equivalently in frequency domain, they differ by more than the coherence bandwidth) and can be
independently demodulated (by Fingers) and combined with maximum ratio combining (MRC).Obviously, this gain is limited
by the multi-path intensity profile (MIP).! Multiple antenna will improve the given MIP.The increased SNR through
space processing has two benefits.First it generates a better initial signal in terms of higher SNR.Second, it
cancels more accurately on every stage because of lower BER.The paper gives recursive equations for both SNR and BER
for each cancellation stage.The paper also derives closed-form expressions for both SNR and BER for each stage as a
function of space-and-time-diversity order, the number of needed iterations, and initial SNR condition.This allows us
to find the performance convergence rate with ease.The analysis also shows the space processing gain is significant
compared to time processing alone.The paper also provides the simulation results, which agree with the theoretical
analysis.
Paper 4.8.1.14
Code Acquisition System Using Periodic Property of PN Code in Rayleigh Fading Channel
In this paper, we perform a performance analysis of serial search acquisition scheme using AWGN rejection filter in
Rayleigh fading channel and propose robust acquisition scheme using reference filter, which is utilized to vary
threshold at fading rate, in Rayleigh fading channel.AWGN rejection filter is utilized to evaluate running average for
compensating channel gain.
Paper 4.8.1.15
An adaptive channel estimation scheme for DS-CDMA systems
An adaptive channel estimation scheme for DS-CDMA systems is proposed.The proposed method is to store a precalculated
bank of coefficients of pilot filters and automatically select the best one according to the estimated vehicle speed.For
this purpose, the computationally efficient method to estimate the vehicle speed is introduced using downsampling
property.The proposed channel estimation method with introduced vehicle-speed-estimation -method provided 2dB gain and
performed better over existing ones.
Paper 4.8.1.16
Multi-user Detection Using CMA & The Cancellation Method In Fast-Fading Channels
In this paper, we introduce a modified interference cancellation scheme for multi-user detection in DS/CDMA.The
interference cancellation schemes have been investigated to overcome near-far problem and MAI(Multiple Access
Interference).Among them, nonlinear detector(parallel or successive or hybrid interference canceller) and adaptive
detector appear to be attractive for different reasons.But PIC requires more hardware, and SIC faces the problems of
power reordering and large delays.And the adaptive detector achieves the good performance using the adaptive filter
conducted iteration algorithm.But it requires many iterations for convergence.In this paper, we propose a new hybrid
interference cancellation combining adaptive filter using CMA(Constant Modulus Algorithm) and the cancellation method.
The proposed IC structure does extract the following characteristics.; (1) it has the same BER performance only using
smaller iterations than conventional adaptive detector, (2) it has the better performance than conventional adaptive
detector about same iterations for convergence, (3) the detector having adaptive filter requires less complexity than
nonlinear detector.
Paper 4.8.1.17
Performance of Coherent Square M-QAM with Lth order Diversity in Nakagami-m Fading
The symbol error rate (SER) performance of coherent square M-ary quadrature amplitude modulation (MQAM) with Lth order
diversity in frequency non-selective slowly Nakagami * m fading environment corrupted by additive white Gaussian noise
(AWGN) is presented.The diversity combining technique considered in this paper is maximal ratio combining (MRC) with
identical channels.The derived expression for SER is in terms of a single finite integral and an integrand composed of
elementary (exponential and trigonometric) functions.Because of its simple form , the expression readily allow
numerical evaluation for cases of practical interest.The solution presented in this paper is general enough so that it
includes half Gaussian fading (m = 0.5), Rayleigh fading (m = 1), and non fading (m = * EMBED Equation.3 *) as special
cases.The results are plotted as SER versus signal to noise ratio ( SNR ) for various values of m and L to examine the
dependence of performance ! m and L.The results presented are expected to provide useful information needed for
exploiting the use of diversity for better design of communication systems for Nakagami * m fading environment.
Keywords- MRC reception, error probability, MQAM, Nakagami-fading, wireless communication.
Paper 4.8.1.18
The General Procedure For Designing a MTCM Scheme With Biorthogonal Symbol Sets
Traditionally, research work ralated to TCM and MTCM concentrated on multi-level/phase signal sets, and there lacks
efficient application of MTCM in spread spectrum modulation system.We propound the concept of employing biorthogonal
symbol (sequence) set as symbol set in MTCM as a way to apply MTCM technology to CDMA system.The general procedure for
designing a MTCM scheme with biorthogonal symbol sets is discussed in this paper.Simulation results show that: with
simple 2-state multiple trellis coded biorthogonal sequence modulation scheme, we can achieve 3.5dB coding gain over
uncoded scheme on AWGN channel.With a 4-state MTCM scheme, a coding gain of more than 6.5 dB can be achieved.
Paper 4.8.1.19
SDR-Based Digital Channelizer/De-Channelizer for Multiple CDMA Signals
In this paper, we present results on IF/baseband up/down direct digital conversion and multiple
channelizer/de-channelizer software defined radio (SDR) modules which are implemented using high speed ADC, DAC and
FPGA,for IS-95 code division multiple access (CDMA) systems.The implemented channelizer can directly down-convert
multiple channel IS-95 CDMA IF signals in 65 MHz - 75 MHz band to the baseband, and selectively process (or analyze)
specific channel signals based on polyphase analysis filter bank techniques.Moreover, the analyzed baseband signals of
multiple channels can be directly up-converted and synthesized in the de-channelizer.We have deployed the implemented
system in IS-95 CDMA optical digital repeaters for PCS applications.
Paper 4.8.1.20
A Fast Software Method of Decorrelating Multiuser Detector in W-CDMA System
In our paper, a fast software processing method of decorrlating multi-user detector with matrix (vector) representation
and linear equation group solution for W-CDMA communication system is proposed.The performance of proposed method is
much better than that of conventional decorrelating method, and the complexity is lower than decorrelating receiver.
Paper 4.8.1.21
INTEGRATED DESIGN OF ADAPTIVE RECEIVERS AND CDMA/PRMA MULTIMEDIA MEDIUM ACCESS SCHEME
Advanced signal processing techniques,such as the adaptive antenna (AA) and the adaptive equalizer (AE), have been
proven to be useful in bringing benefits to the performance of DS-CDMA systems.In this paper, based in the application
of AA and AE techniques in the CDMA/PRMA and CDMA/ALOHA medium access schemes, we evaluate the impact of these
techniques in the integrated design of multimedia packet-switched systems.Considering perfect power control and
Nakgami-m fading scenarios, the aspects investigated include: (i) diversity gain with AA;(ii) performance of joint AE
and spatial diversity with maximal ratio combining;(iii) performance of adaptive receivers in multicode/multislot
approaches for WWW browsing and VBR video traffic; etc.
Paper 4.8.1.22
An efficient call admission control with mobility information in wireless networks
A challenge issue in future personal communication systems (PCS) is how to guarantee quality of service (QoS) requirement
over lifetime of mobile connections and at the same time to make efficient use of network resources.In this paper, a
distributed call admission control (CAC) scheme incorporating user mobility information which is defined as predicted
handoff probabilities of each mobile user, is proposed for QoS provisioning in wireless networks.The significant
strength of incorporating user mobility information in CAC scheme is to guarantee a required QoS and to make efficient
use of resources as well under all traffic conditions.Simulation results show that a significant improvement of resource
utilization is achieved under the non-uniform traffic load with QoS constrain.
Paper 4.8.1.23
Determining Optimal Numbers of Traffic Channels in BS and Vocoders in MSC
When an MS (Mobile Station) initiates a call in the cell of a BS (Base Station), a traffic channel in the BS and a
vocoder in the MSC (Mobile Switching Center) to which the BS is connected should be assigned for the service of the
call.If there is no idle traffic channel in the BS or vocoder in the MSC, the initiated call is blocked and lost.So,
the numbers of traffic channels in a BS and vocoders in an MSC should be large enough to guarantee a given blocking
probability of a call due to the lack of traffic channels and vocoders.In this paper, considering the cost for
supporting the traffic channels and vocoders, the optimal numbers of traffic channels in a BS and vocoders in an MSC are
obtained to guarantee a given call blocking probability and incur the minimal cost.
Paper 4.8.1.24
Capacity Analysis of a UTRA-TDD System
Standardization of third-generation mobile communication systems is now rapidly progressing in all major regions of the
world.In January 1998 ETSI selected the basic technology for the UMTS terrestrial radio access (UTRA) system.UTRA
includes both a frequency-division duplex (FDD) mode and time-division duplex (TDD) mode.The FDD mode is based on pure
WCDMA while the TDD mode includes an additional time-division multiple access (TDMA) according to the TD/CDMA proposal.
In this paper an study has been performed to estimate the capacity of a UTRA-TDD system.The results we have got allow
us to make the dimensioning of a system according to the type of traffic that it has to bear.
Paper 4.8.1.25
Edge Compact and Edge Classic Data Transaction Times
The paper provides some bounds and averages of data transaction times in the system for minimum frequency deployments of
Edge Classic and Edge Compact.Edge Compact is a variation of E-GPRS currently being standardized to allow in very
limited spectrum allocations.The averages and bounds are determined by closed form analysis.Monte-Carlo simulation is
also done to provide further insight.The bandwidth allocated to control and data transfer operations are looked into as
separate quantities.
Paper 4.8.1.26
Outage probability of a multicarrier DS/CDMA system with adaptive antenna array
In this paper, outage probability of a proposed multicarrier DS/CDMA system with adaptive antenna array is analyzed and
simulated in a multipath fading channel which is modeled as a Nakagami-m distribution.A linear antenna array with
equi-spacing identical array elements and half wavelength antenna spacing is considered.The simulation results of
outage probabilities are compared for the sample adaptive algorithms (LMS, NLMS, RLS, etc) and the block adaptive
algorithms (Wiener solutions, MRC).It is confirmed that the adaptive antenna array is very effective to enhance the
system capacity of a multicarrier DS/CDMA system.
Paper 4.8.1.27
A new adaptive routing scheme based on the traffic characteristics in mobile ad-hoc
networks
In this paper, we propose a new adaptive routing scheme based on the traffic characteristics.And the performance
measures are the mean number of hops, routing reestablishment rate and paging cost.If a mobile node want to transmit
real-time traffic, traffic is routed through the shortest path in a flat ad-hoc network in order to minimize the mean
number of hops and the routing path reestablishment rate.On the other hand, if a mobile node want to transmit non
real-time traffic, traffic is routed through sub-optimal path in a hierarchical ad-hoc network to accomplish mobility
management easily and minimize paging cost.In the simulation, we compare the performance between the proposed scheme
and the conventional scheme as the number of mobile nodes increase.
Paper 4.8.1.28
Blocking Performance Evaluation of Link between MSC's for CDMA Inter-MSC Soft Handoff
CDMA (Code Division Multiple Access) is a promising air interface technique for digital cellular systems.The soft
handoff between base stations is one of many important features of CDMA for the mobile station crossing the cell
boundaries.When a mobile station during a call moves to an adjacent MSC (Mobile Switching Center)'s service area, we
propose that the traffic data from the new base station be carried to the old MSC through the link between MSC's.The
old MSC receives multiple traffic data from the base stations that are serving the mobile station requesting the
inter-MSC soft handoff.In this paper, we will develop an analytical approach for calculating the traffic load on the
link by the soft handoffs between MSC's.The service area of an MSC is defined as the union of the service areas of the
base stations of the MSC and is assumed to have a hexagonal shape.The blocking probability of the soft handoff between
MSC's due to the shortage of the link capacity will be derived by Erlang loss formula.
Paper 4.8.1.29
Design of Semi Blind Decision Feedback Equalizer with Short Training Sequence
Semi blind Decision Feedback Equalizers (DFE) with very short training sequence seems to be a good alternative to blind
DFE.Due to their recursive structure they present good intersymbol interference cancellation in the presence of
time-varying channels.Moreover, due to the training sequence, the ill-convergence can be avoided.However, the design
of the semi-blind DFE with very short training sequence requires powerfull theoretical analysis.The exact transient
analysis of semi-blind DFE given in this paper allow us to give a good initialization in order to avoid ill convergence.
Paper 4.8.1.30
Dynamic Rate Control based on Interference and Transmission Power in 3GPP WCDMA System
Since the available resource is time-varying due to burstness characteristics of data tramsmission and the different
quality of service according to the users class is required in the IMT-2000 system, the efficient resouce use and QoS
support for users are needed.In this paper, we propose a dynamic rate control method for throughput enhancement and
different QoS support of each user in the 3GPP WCDMA system.We adjust the user's data transmission rate according to
the total interference and transmission power by one available step.In simulation, the proposed rate control method is
compared with those of two other methods in which the transmission rate is determined at the call admission level and it
is not changed during the data transmission.
Paper 4.8.3.1
Mobile Network Traffic Forecasting
The importance of traffic forecasting cannot be understated on such a network, where the need for acceptable service
quality has to be weighed against the cost and time involved in commissioning new base stations or installing additional
transceivers.A typical lead- time for a new site to be in-service is of the order of 12 months, whilst new transceivers
may take up to a month to install.The proposed mobile network traffic forecasting technique is intended to replace the
spreadsheet system to both improve the accuracy and speed at which a long-term forecast may be produced.In addition, the
approach allows the analysis of large coverage regions and can operate in parallel to investigate multiple traffic growth
scenarios (i.e.BDBH, TCBH etc.).
Paper 4.8.3.2
A New Multimedia Network Architecture Using 3G CDMA2000
The third generation (3G) of wireless communications can provide mobile Internet and Multimedia services including video
and audio conferencing.In order to support these advanced multimedia services CDMA2000 has been designed for high speed
Internet based packet-data.The information data rates of CDMA2000 can handle multimedia packet-data with current
compression standards for video and audio.Thus, we propose a new network architecture using 3G CDMA2000.Experiment of
Session Initiation Protocol (SIP) signaling showed the possibilities and technical viability of the proposed approach.
Paper 4.8.3.3
Effect of Various Threshold Settings on Soft
Handoff Performance in Various Propagation Environments
In order to benefit from the advatages of the soft handoff, it is important that the handoff parameters be well set.
This paper analyzes the sensitivity of the soft handoff performance to variations in the propagation environment.The
sensitivity analysis is then used to design a robust algorithm so as to reduce possible holes in coverage and excessive
handoff overhead.The tradeoff between the sensitivity reduction and the mean number of updates is presented.
Paper 4.8.3.4
Simple Nonlinear GMSK REceiver for Multipath Environment
In previous work, Envelope-Aided Viterbi receivers have shown to be highly effective nonlinear receivers for constant
envelope frequency modulated signals in frequency selective multipath transmission with Limiter Discriminator (LD)
demodulation.Due to the strong dependence of the instantaneous amplitude of the multipath received signal with the
transmitted data sequence when multipath transmission exists and the dependence of the noise statistics with it, a
spectacular performance improvement can be achieved using both the amplitude and frequency information.Because of the
essentially nonlinear nature of the Tx-Rx chain, Maximum Likelihood Sequence Detectors (MLSD) are a suitable approach.
Somehow, even though an efficient implementation algorithm, is available for MLSD (the Viterbi Algorithm, VA), the
computational complexity is still very high, and the delay introduced by the sequence detector can be, for some
applications, inadmissible.For this reasons, a simple architecture is proposed in this paper that also makes use of both
amplitude and frequency information with minimal computational complexity.Apart from the intrinsic value of the proposed
algorithm, that can be view as a variation of the conventional VA with zero decision depth, our results will show the
power of Amplitude-Aided decision for a sub-optimal MLSD-like receiver.
Paper 4.8.3.5
An implementation method of a turbo-code decoder using a block-wise MAP algorithm
In this paper, several design methods for the MAP decoder are illustrated.The proposed structure is based on block-wise
MAP algorithm, so that the requirement of memory is drastically reduced.In addition, by using the time-shared
processing of a pipe-lined structure, the complexity and the decoding speed of the proposed MAP decoder can be compared
with the orders of a SOVA decoder.
Paper 4.8.3.6
MAP-Algorithm with Fixed-Point Representation for Software Radios
IMT2000 handhelds must be able to perform at least two or three of the IMT2000 modes.Additionally it is desirable, that
IMT2000 handhelds are also able to include second generations services like GSM, IS-136 or IS-95.So, an IMT2000 mobile
may only be realized with a transceiver structure which is entirely software programmable; a so called Software Radio.
All baseband functions are implemented in a general, parametrized way, so that they can be used for the selected
standards.For example the MAP-algorithm can be used for turbo-decoding in UMTS or as equalizer and convolutional decoder
in GSM.To ensure maximum flexibility the MAP-algorithm should be implemented on DSP's.For this goal the necessary word
width and the possibility of parallel computing are analysed in the paper.
Paper 4.8.3.7
NOISE-REDUCED GMDF FOR ACOUSTIC ECHO CANCELLATION IN MOBILE ENVIRONMENTS
A noise-reduction (NR) enhancement to the Generalized Multi-Delay Frequency Domain algorithm (GMDF) involving minimal
additional computations is presented.Findings are presented on the ability of the algorithm to suppress street, office,
air-conditioning and car noise from the microphone signal in hands-free mobile telephony.For an additional 11 N/P real
multiplies and 8 N/P real additions per output sample, where N is the block size and P is the amount of output samples
per GMDF iteration, results show an average increase in echo return loss enhancement (ERLE) of 9dB at low SNR (-5dB) and
6dB at higher SNR (15dB).
Paper 4.8.3.9
Adaptive Dynamic Channel Allocation Scheme for Wireless Multimedia
As the size of the wireless mobile community and their demands increase rapidly, spectrum resource management remains an
important topic in the near and distant future.we propose a dynamic channel allocation strategy based on traffic
characteristics and channel utilization.Proposed scheme will increase the efficiency of channel usage.Primary analysis
shows that proposed scheme increase system performance.
Paper 4.8.3.10
Robust DFE for Limiter-Discriminator based HIPERLAN receivers
HIgh PERformance Local Area Network (HIPERLAN) was developed within the European Telecommunications Standards Institute
(ETSI) during the period 1991 to 1996 and the first commercial systems based in it will be commercially available in the
market during 2000.A great expansion of the worldwide wireless LAN market is expected by this year.HIPERLAN/1, a modern
Wireless Ethernet, offers a maximum user data rate per channel over 18 Mbps (23.5 Mbps over air), the highest data rate
of any existing specification, with Quality of Service (QoS) in the delivery of real-time video and voice, and will
support both Isochronous and Asynchronous services.HIPERLAN uses the constant envelope modulation GMSK with BT=0.3 and
modulation index h=1/2, with RF carriers in the 5.176 to 5.270 MHz range, and the data burst contains a synchronization
and training sequence of 450 bits and a number (at least one) of blocks of 496 bits of interleaved, BCH(31,26) coded
data.For pedestrians speeds of 1-2 m/s, the channel can be considered stable over a data burst, and no channel tracking
is necessary after an initial estimation.Typical system range will be up to 50 meters in an office environment.One of
the main restrictions to the coverage area being the frequency selective multipath channel that appear due to the small
symbol duration 42.5ns.Among all the possible reception architectures, noncoherent demodulation using
Limiter-Discriminator (LD) has shown to be a simple, cheap and robust options CPM.LDs are especially suited for fading
or mobile channels, where frequency and phase synchronism complicates coherent demodulation.However, conventional
Decision Feedback Equalization (DFE) provide poor performance when applied to LD receivers due to the nonlinear
characteristics of the signal at the output of the discriminator device, and nonlinear detectors such as Maximum
Likelihood Sequence Detection (MLSD) using the Viterbi Algorithm, even though very robust to channel conditions, can be
too complex to implement for the high data rate required.In this contribution we will show that, due to the correlation
of the amplitude information with the transmitted data at the input of the Limiter when multipath transmission is
present, the performance of a DFE scheme can be significantly improved in terms of Bit Error Rate (BER) and percentage of
error-free transmissions (Outage Probability) with a minimum complexity increase by means of the joint use of the LD
output and the instantaneous amplitude at the output of an envelope detector.
Paper 4.8.3.11
Hybrid Linear and Non-linear PIC for WCDMA
We propose a suboptimal low-complexity parallel interference cancellation (PIC) multiuser receivers for WCDMA
frequency-selective Rayleigh fading channels.Users are divided into groups according to their spreading factors.Users
with the lowest spreading factor will be detected first using non-linear PIC while Users with the largest spreading
factor will be detected last using linear PIC, subtracting interferences regenerated by users with lower spreading
factor.In contrast to the conventional PIC receivers, simulation results denote that the proposed scheme is shown to
better BER performance, only adding a subtracter.
Paper 4.8.3.14
Signal-strength-based Cellular Location Using Dynamic Window-width and
Double-averaging Algorithm
For signal-strength-based cellular location systems, the primary source of error is Raleigh fading and lognormal
shadowing.Variations in the signal strength can be as great as 30-40 dB over distances on the order of a half
wavelength.Signal strength averaging can help, but there are two restrictive factors.The first is that the two kinds
of fading have different probability density function and the optimum estimation of local mean signal strength can not
be obtained in the same reference.The second is that low-mobility MS may not able to average out the effects of the
fading.Therefor, this paper suggests a double-averaging algorithm with dynamic widow-width to combat both factors
mentioned above.The results of computer simulation proved that our methods improve location accuracy by 30% than
traditional methods.And, with the aid of dynamic window-width, sufficient location accuracy can be obtained while MS is
in low mobility.
Paper 4.8.3.15
Wireless Data Transmission for High-Speed Train Control
The fast development of wireless communication technology makes it possible to transmit datum, used for train control,
between train and ground, through radio.The key of the question is the reliability of wireless transmission.In the
high-speed railway, trains speed may reach 500Km/h.The maximum Doppler frequency at carrier frequency of 900MHz is
417Hz.We can not ignore the effect of Doppler frequency shift as usual.In this paper we analyze the effect of Doppler
frequency on data transmission, give some measures to improve the data link quality.
Paper 4.8.3.18
An Investigation of inter-cell interference in UTRA-TDD system
Inter-cell interference in the UTRA-TDD system is investigated.There are some specific interference modes in the TDD
mode.The inter-cell interference contains the interference caused by the adjacent cells and the interference caused by
the adjacent channels.Some simulations are done to study the interference.Impacts of four different interference
instances were considered in the simulation.Some interesting results are given from the simulations.Any little bit of
asynchronism between the adjacent cells will affect the capacity of the uplink severly, which is mainly caused by the
BS-BS interference.Two cells use the adjacent channels can be co-located at the same site if they are synchronized.
Paper 4.8.3.21
Techniques to provide coverage and capcity in GSM pico-cell environment
In this paper, the following GSM pico-cell deployment techniques are described: External Illumination: Undedicated
Cell Enhancer (RF repeater): Undedicated Centrally based BTS (RF distribution): Dedicated Distributed BTS (baseband
Distribution): Dedicated Multi-layer (Hybrid System): Dedicated The following techniques to distribute the signal (RF
or baseband) around a building are also described: RF Distribution using passive or active coaxial cable. RF
Distribution using passive or active black mode fibre-optic cable. Baseband Distribution using HDSL or fibre-optic
cable technology The paper covers the following: 1.An overview of pico-cell systems and their applications 2.The
description of the requirements including coverage, capacity and grade of service.3.The description of the deployment
techniques including their applications, advantages and disadvantages.4.The matching between the requirements and the
deployment techniques.5.Conclusions.
Paper 4.8.3.22
Comparison of Indoor Geolocation Methods in DSSS and OFDM Wireless LAN Systems
The DSSS and OFDM techniques are most widely used in the existing wireless LAN standards (IEEE 802.11 and HIPERLAN).In
this paper, we first compare those aspects of DSSS and OFDM wireless LAN standards that are relevant to geolocation
consideration.Then we compare the performance of the DSSS IEEE 802.11 and OFDM HIPERLAN/2 (IEEE 802.11b) based indoor
geolocation systems.Computer simulation results are presented to compare the performance in terms of ranging and
positioning accuracy.
Paper 4.8.3.23
Adaptive Antenna Algorithms for Multimedia Communications
This paper presents an investigation into receiver algorithms for multiple transmit and receiver systems.Asimulation
tool has been developed which uses powerful convolutional coding to optimise performance.A number of candidate receiver
algorithms are tested to compare performance and complexity.
Paper 4.8.3.26
Estimating the Gains of Adaptive Antenna Systems for GPRS and EDGE Data Services in
GSM Networks
In this paper we present system level simulations results on adaptive antenna systems for Global System for Mobile
Communications (GSM) networks incorporating mixed voice, General Packet Radio Service (GPRS) and Enhanced Data Rates for
the GSM Evolution (EDGE) services.Fits best into wireless personal communication systems under 2.5G system performance.
Paper 4.8.3.29
Flexible Security and a New Structure for Electric Commerce on Software Radio
We summarize the security necessary for software radio systems, and propose a new flexible structure for security systems
on software radio.We introduce a new electric commerce scheme for software radio that utilizes the ability of software
radio to switch between different algorithms for electric commerce.We evaluate the performance of the cryptographic
algorithms used in electric commerce on various platforms including software radio systems, as basic research toward the
implementation of software radio.
Wednesday Track1 08:30AM Propagation & Channel Models
Wednesday Track1 10:30AM Propagation & Channel Models
Wednesday Track1 1:30PM Propagation & Channel Models
Wednesday Track1 3:30PM Propagation & Channel Models
Wednesday Track2 08:30AM Multimedia
Wednesday Track2 10:30AM Multimedia
Wednesday Track2 1:30PM Multimedia
Wednesday Track2 3:30PM Multimedia
Wednesday Track3 08:30AM Wireless Access
Wednesday Track3 10:30AM Wireless Access
Wednesday Track3 1:30PM Wireless Access
Wednesday Track3 3:30PM Wireless Access
Wednesday Track4 08:30AM Transmission Technology I
Wednesday Track4 10:30AM Transmission Technology I
Wednesday Track4 1:30PM Transmission Technology I
Wednesday Track4 3:30PM Transmission Technology I
Wednesday Track5 08:30AM Transmission Technology II
Wednesday Track5 10:30AM Transmission Technology II
Wednesday Track5 1:30PM Transmission Technology II
Wednesday Track5 3:30PM Transmission Technology II
Wednesday Track6 08:30AM Wireless PCS I
Wednesday Track6 10:30AM Wireless PCS I
Wednesday Track6 1:30PM Wireless PCS I
Wednesday Track6 3:30PM Wireless PCS I
Wednesday Track7 08:30AM Wireless PCS II
Wednesday Track7 10:30AM Wireless PCS II
Wednesday Track7 1:30PM Wireless PCS II
Wednesday Track7 3:30PM Wireless PCS II
Wednesday Track8 08:30AM Poster B
Wednesday Track8 1:30PM Poster C
Thursday Track1 08:30AM Mobile Satellite
Thursday Track1 10:30AM Mobile Satellite
Thursday Track1 1:30PM Mobile Satellite
Thursday Track1 3:30PM Mobile Satellite
Thursday Track2 08:30AM Transportation
Thursday Track2 10:30AM Transportation
Thursday Track2 1:30PM Transportation
Thursday Track2 3:30PM Transportation
Thursday Track3 08:30AM Wireless Access
Thursday Track3 10:30AM Wireless Access
Thursday Track3 1:30PM Wireless Access
Thursday Track3 3:30PM Wireless Access
Thursday Track4 08:30AM Transmission Technology I
Thursday Track4 10:30AM Transmission Technology I
Thursday Track4 1:30PM Transmission Technology I
Thursday Track4 3:30PM Transmission Technology I
Thursday Track5 08:30AM Transmission Technology II
Thursday Track5 10:30AM Transmission Technology II
Thursday Track5 1:30PM Transmission Technology II
Thursday Track5 3:30PM Transmission Technology II
Thursday Track6 08:30AM Wireless PCS I
Thursday Track6 10:30AM Wireless PCS I
Thursday Track6 1:30PM Wireless PCS I
Thursday Track6 3:30PM Wireless PCS I
Thursday Track7 08:30AM Wireless PCS II
Thursday Track7 10:30AM Wireless PCS II
Thursday Track7 1:30PM Wireless PCS II
Thursday Track7 3:30PM Wireless PCS II
Thursday Track8 08:30AM Poster D
Thursday Track8 1:30PM Poster E
Dr.Xiongwen Zhao
Dr.Jarmo Kivinen
Prof Pertti Vainikainen
Radio Laboratory, Helsinki University of Technology
Mr Hao Xu
Dr Vikas Kukshya
Mr Theodore Rappaport
Mobile and Portable Radio Research Group, Virginia Tech
Mr Jean Philippe Kermoal
Mr Klaus I.Pedersen
Dr Preben E.Mogensen
Center for PersonKomunikation, Aalborg University
Mr Byung-ki Kim
Dr Warren Stutzman
Dr Dennis Sweeney
Virginia Polytechnic Institute and State University
Dr Jonas Medbo
Mr Jan-Erik Berg
Ericsson Radio Systems AB
Mr.Pejman Hafezi
Dr.Andy Nix
Dr.Mark Beach
University Of Bristol
Dr William Scanlon
Mr Francesco Villanese
Dr Noel Evans
Centre for Communications Engineering, University of
Ulster
Mr Cheolhang Cheon
Mr.Henry Bertoni
Mr.George Liang
Polytechnic University
Mr M J Mughal
Dr A.M.Street
Dr C.C.Constantinou
The University of Birmingham
Dr Gert F Pedersen
Dr Patrick Eggers
Aalborg University
Ari Hottinen
Olav Tirkkonen
Risto Wichman
Nokia Research Center
Mr Klaus Hugl
Prof Ernst Bonek
Institut fuer Nachrichtentechnik, Tech.Univ.Wien
Mr Thomas Svantesson
Chalmers Univ.of Tech.
Dr Angel Lozano
Dr Farrokh Farrokhi
Dr Gerard Foschini
Lucent Technologies
Mr Roger Gaspa
Prof Javier R.Fonollosa
Universitat Politcnica de Catalunya
Mr Satoru ISHII
Mr Atsushi HOSHIKUKI
Prof Ryuji KOHNO
Futaba Corporation
Ms Yahong Zheng
Mr.Rafik Gougran
Mr.Mohamed El-Tanany
Carleton University
Dr Tae-Gyu Chang
Mr Jae-Hwa Kim
Mr Chong-Yoon Kim
School of Electrical Engineering, ChungAng University
Dr Francois Chin
Mr Yan Zhou
Dr Ying-Chang Liang
Centre for Wireless Communications
Mr.Jaehak Chung
Mr.Sang-Youb Kim
Dr.Edward Powers
The University of Texas at Austin
Mr.Tatcha Chulajata
Dr.Hyuck M.Kwon
Wichita State University
Mr.Peter Papazian
Mr.Perry Wilson
Mr.Lo Lo
National Telecommunications and Information Administration
Dr Ivan Howitt
Mr Fahed Awad
University of Wisconsin - Milwaukee
Mr Keizo Cho
Mr Yasushi Takatori
Mr Kentaro Nishimori
Nippon Telegraph and Telephone Corporation
Dr Bo Gransson
Mr Jzsef Barta
Dr Bo Hagerman
Ericsson Research
Dr Ivan Howitt
University of Wisconsin - Milwaukee
Dr Ying-Chang Liang
Dr Francois P.S.Chin
Centre for Wireless Communications
Mr Kazunori Watanabe
Dr Ryuji Kohno
Yokohama National University
Mr.David Hastings
Dr.Hyuck Kwon
Wichita State University
Dr.jinho Choi
Dept.of Electronic Engineering, Konkuk University
Dr Yu-Kwong Kwok
Dr Vincent K N Lau
Department of EEE, The University of Hong Kong
Mr Michael Meurer
Mr Apostolos Papathanassiou
Mr Tobias Weber
University of Kaiserslautern
Dr.Asis Nasipuri
Dr.Samir Das
The University of Texas at San Antonio
Mr Kyu-Tae Jin
Dr Dong-Ho Cho
Korea Advanced Institude of Science & Technology
Dr.Shiao-Li Tsao
Industrial Technology Research Institute
Dr Mostafa Nofal
Dr Nawal el-fishawy
eng.saied abd el atty
Faculty of electronic engineering
Dr.Anna Hac
University of Hawaii
Dr Zhang Xiaodong
Prof Bi Guangguo
Southeast Univ.,China
Ms Cristina Comaniciu
Dr Narayan Mandayam
Mr David Famolari
WINLAB, Rutgers University
Mr.Rajnish Sinha
Dr.Roy Yates
WINLAB
Dr.Symeon Papavassiliou
Dr.George Kotsakis
New Jersey Institute of Technology
Joonsuk Kim
John Cioffi
Stanford University
Jung-Hyun Choi
Dr
Nak-Myeong Kim
Ewha women's university, in Seoul , Korea
Mr Seung Sik Choi
Dr.Dong Ho Cho
KAIST, Electrical Eng.
Mr Young-Seo Park
Dr Scott Miller
University of Florida
Dr.Fuyun Ling
Qualcomm Incorporated
Mr Frederik Petre (with accent on last
e)
Dr Marc Moonen
Dr Marc Engels
IMEC
Ms Assia Semmar
Dr Tue Huu Huynh
Dr Michel Lecours
Laval University
Dragan Samardzija
Narayan Mandayam
Ivan Seskar
WINLAB, Rutgers University
Mr.Bruce McNair
Dr.Leonard Cimini
Mr.Nelson Sollenberger
AT&T Labs - Research
Mr Salam Zummo
Dr Al-Semari Saud
King Fahd University of Petroluem & Minerals
Mr Ramon Schlagenhaufer
Dr Brent R.Petersen
Dr Abu B.Sesay
TRLabs
Dr.Ralf Weber
Ericsson Eurolab Deutschland GmbH
Prof Hideo Kobayashi
Mr Medina Luciano
Mie University
Rohit Negi
John Cioffi
Stanford University
Prof Hiroshi Suzuki
Dr Yukitoshi Sanada
Mr Rikuhiro Hanai
Tokyo Institute of Technology
Mr Rajanish Rajanish
Dr P.W.Baier
University of Kaiserslautern, Germany/IISc, India
Mr.Anders stergaard Nielsen
Ms.Sari Korpela
Nokia Mobile Phones
Dr.Yeon Ho Chung
Dr.Ki Hong Song
Dongeui University, Pusan, Korea (South)
Dr.Behnam Kamali
Mr.Henderson Benjamine
Mercer University
Mr SAFFET BAYRAM
Mr JAMES HICKS
Dr ROBERT BOYLE
Mobile and Portable Radio Research Group, Virginia Tech
Mr Shingo Suwa
Dr Takahiko Saba
Mr Masayuki Ariyoshi
Keio University
Mr Akihito Hanaki
Dr Takeo Ohgane
Dr Yasutaka Ogawa
Hokkaido University
Mr Gyongsu Lee
Sin-Chong Park
Information and Communications University
Dr Alex Grant
Institute for Telecommunications Research
Mr Bjorn A Bjerke
Dr Zoran Zvonar
Dr John G.Proakis
Northeastern University
Dr Timothy Schmidl
Dr Alan Gatherer
Dr Xiaodong Wang
Texas Instruments
Mr Carlos Aldana
Mr Atul Salvekar
Mr Jose Tellado
Stanford University
Dr Bin Li
Dr Wen Tong
Dr Rui Wang
Nortel Networks
Mr Javier Gozalvez
Prof John Dunlop
University of Strathclyde
Mr Eiji Okamoto
Dr Hiroyo Ogawa
Communications Research Laboratory
Dr Stefan Brck
Bell Labs, Lucent Technologies
Mr Hyon-Sock Chang
Mr Keun-Moo Lee
Dr Yong H.Lee
Department of Electrical Engineering, KAIST
Eng.Andrea Tonello
University of Padova - DEI - Department of Electronics
Mr.Minyi Zhao
Dr.Ali N.Akansu
New Jersey Center for Mulimedia Research, ECE Dept.,
Mr Cem Saraydar
Dr Narayan Mandayam
Dr David Goodman
Wireless Information Network Laboratory
Mr Pablo Jose Ameigeiras Gutierrez
Dr Jeroen Wigard
Dr Preben Mogensen
Center for PersonKommunication (Aalborg University)
Dr Amitava Ghosh
Dr Louay Jalloul
Mr Mark Cudak
Motorola
Dr Anand Dabak
Tim Schmidl
Chaitali Sengupta
Wireless Communications Branch, Texas Instruments
Jason Chen
Louay Jalloul
Motorola, Inc.
Mr Thrasivoulos Griparis
Mr Robert Joyce
Dr Jamal Khalab
Fujitsu Europe Telecom R&D Centre Ltd
Mr Takeshi Kokubo
Dr Shoichiro Yamasaki
Dr Masao Nakagawa
Dept.of Electrical Engineering, Keio University
Mr Peter Gunreben
Dr Kiran Rege
Dr Jens Mckenheim
Lucent Technologies
Dr Sandrine Merigeault
Mr Mickael Batariere
Dr Jean Noel Patillon
MOTOROLA
Mr Dimitrios Vergados
Mr Angelos Liveris
Mr Evangelos Verentziotis
National Technical University of Athens
Mr Chieh-Ho Lee
Dr Chung-Ju Chang
National Chiao Tung University
Dr George Karagiannidis
Dr Stavros Kotsopoulos
Wireless Telecommunications Laboratory
Mr Davide Imbeni
Mr Magnus Karlsson
Ericsson Telecomunicazioni SpA
Mr Manouchehr Mahmoudi
Dr.Elvino S.Sousa
University of Toronto
Dr.Srinath Hosur
Dr.Anand Dabak
Texas Instruments Inc.
Dr Tadao Nakagawa
Mr Katsuhiko Araki
NTT Network Innovation Laboratories
Mr Hoon Kim
Mr Jayong Koo
Dr Youngnam Han
Information and Communication Univeristy
Dr.Ming Zhang
Mr.Alan MacDonald
AT&T Wireless Services
Dr Qiu Ling
prof Zhu Jinkang
University of Science & Technology of China
Dr.Peter Wang
Dr.Marilynn Green
Nokia Research Center
Dr Stefano Galli
Telcordia Technologies, formerly Bellcore
Ashvin Chheda
Nortel Networks
Dr David Lee
Dr William C.Y.Lee
Vodafone AirTouch
Ms.Janise McNair
Dr.Ian Akyildiz
Dr.Sridhar Radhakrishnan
Georgia Institute of Technology
Mr.Tatcha Chulajata
Dr.Hyuck M.Kwon
Wichita State University
Dr Fredrik Gunnarsson
Dr Fredrik Gustafsson
Department of Electrical Engineering
Dr Werner Mohr
Siemens AG
Dr.Che-Li Lin
CCL/ ITRI (Industrial Technology Research Institute)
Dr Mario Hueda
University of Cordoba - Argentina
Mr.Muhammad Kazmi
Mr.Philippe Godlewski
Mr.Christophe Cordier
Ecole Nationale Superieure des Telecommunications
Mr.Quentin Spencer
Dr.Lee Swindlehurst
Brigham Young University
Dr Larbi Talbi
Dr Gilles Delisle
Universit du Qubec Hull
Mr Iigo Cuias
Ms Mercedes Sanchez Varela
Dr Manuel Garcia Sanchez
Universidade de Vigo
Mr.HECTOR CARRASCO-ESPINOSA
Dr.JOSE DELGADO-PENIN
Dr.JAVIER RODRIGUEZ-FONOLLOSA
UNIVERSITAT POLITCNICA DE CATALUNYA
Ms Anna Zhuang
Mr Markku Renfors
Nokia Mobile Phones
Dr Alister Burr
University of York
Dr.Nishimura Toshihiko
Dr.Ohgane Takeo
Dr.Ogawa Yasutaka
Graduate School of Engineering, Hokkaido University
Mr Istvan Zsolt Kovacs
Mr Patrick C.F.Eggers
Mr Kim Olesen
Center For PersonKommunikation, Aalborg University
Mr Jesper Nielsen
Mr Gert F.Pedersen
Center for PersonKommunikation, Aalborg University
Mr Byoung-Seong Park
Mr Do-Hyung Choi
Dr Han-Kyu Park
Dept.of Electrical & Computer Eng., Yonsei University
Mr Francesco Villanese
Dr William G.Scanlon
Dr Noel E.Evans
Centre for Communication Engineering - University of
Ulster
Dr Rodney Vaughan
Mr Paul Teal
Mr Raviv Raich
Industrial Research Limited
Mr Jeongho Park
Mr Sukhyun Yoon
Dr Chaneon Kang
Information&Telecomm.Lab.Dept.of E&C Eng.Yonsei.Univ.
Mr Ratish Punnoose
Mr Pavel Nikitin
Dr Daniel Stancil
Carnegie Mellon University
Mr.Jing Wang
Dr.James Cavers
Simon Fraser University
Ms Carol Martin
Dr Jack Winters
Mr Nelson Sollenberger
AT&T Labs-Research
Mr Iigo Cuias
Mr Jean-Pierre Pugliese
Dr Akram Hammoudeh
Universidade de Vigo
Perry Wilson
Peter Papazian
Institute for Telecommunication Sciences
Ms.Terri Lowe
Dr Jay Weitzen
TRW
Dr Rodney Vaughan
Industrial Research Limited
Prof Bernard Fleury
Center for PersonKommunikation
Mr Thomas Binzer
Dr Gerd Woelfle
Mr Reiner Hoppe
Institute of Radio Frequency Technology
Dr David Lee
Dr William Lee
Vodafone AirTouch Plc
Jonghyun Lee
ChongHyun Lee
Joohwan Chun
Korea Advanced Institute of Science and Technology
Mr Hironari Masui
Mr Masanori Ishii
Mr Kozo Sakawa
YRP Key Tech Labs
Mr Matthias Stege
Mr Marcus Bronzel
Prof Gerhard Fettweis
University of Technology Dresden
Mr NAOKI KITA
Dr Akio SATO
Dr Masahiro UMEHIRA
NIPPON TELEGRAPH AND TELEPHON CORPORATION
Mr Alain SIBILLE
Mr Juergen KUNISCH
ENSTA
Dr Gert F Pedersen
Aalborg University
Dr Ki-Hong Song
Dr Yeon-Ho Chung
Dongeui Institute of Technology
Mr Jack Smith
Mr Doug Reed
Mr Hande Prashanth
Motorola
Dr Michel Daoud yacoub
School of Electrical and Computer Engineering - UNICAMP
Mr Ruben Fraile
Dr Narcis Cardona
Universidad Politecnica de Valencia
Mr Philippe LASPOUGEAS
Mr Patrice PAJUSCO
Mr Jean-Claude BIC
France Tlcom CNET
Klaus Pedersen
Jean Philippe Kermoal
Preben Mogensen
Aalborg University
Mr Frederiksen Frank
Mr Preben E.Mogensen
Mr Jan-Erik Berg
Aalborg University
Dr Vladimir Mordachev
Belarus State University of Informatics and
Radioelectronics
Mr Ruifeng Zhao
Mr Hailin Jiang
Mr Zhenhui Tan
Modern Communication Research Institute
Mr.Harold Zheng
Ms.Sherry Wang
Dr.John Copeland
Georgia Institute of Technology
Mr Yong-i Kim
Dr Hwang Soo Lee
Dept.EE, Korea Advanced Institute of Science and
Technology
Mr Jung-hee Ryu
Dr Dong-Ho Cho
Korea Advanced Institute of Science and Technology
Mohinder Jankiraman
Ramjee (Dr) Prasad
Delft University of Technology
Dr Chung Gu Kang
Korea University of Korea
Ms Aikaterini Varsou
Dr H.Vincent Poor
Princeton University
Dr Farooq Khan
Lucent Technologies
Mr Amoakoh Gyasi-Agyei
Dr Seppo J.Halme
Helsinki Univ.of Technology, Communications Laboratory
Mr.Osamu Nakamura
Mr.Ishiguro Takayuki
Dr.Ohtsuka Hiroyuki
NTT DoCoMo Inc.
Mr Djamel Sadok
Mr Carlos Morais
Dr Judith Kelner
Centro de Informatica, Universidade Federal de Pernambuco
Dr.Behnam Kamali
Mercer University
Prof Chai Keong Toh
Mr Santithorn Bunchua
Georgia Institute of Technology
syed jafar
Dr
Andrea Goldsmith
Stanford University
Dr.Shiao-Li Tsao
Industrial Technology Research Institute
Mr Zoran Hadzi-Velkov
Mr Boris Spasenovski
Faculty of Electrical Engineering
Mr Yong Bai
Ogielski Andy
WINLAB, Rutgers University
Dr Yuan Dongfeng
Ms Gao Chunyan
Department of Electronics Engineering, Shandong University
Prof Ramjee Prasad
Mr.Carl Wijting
Center for PersonKommunikation, Aalborg University
Dr.Peter McLane
Mr.Srikanth Subramanian
Queen's University
Dr.Ashok Rudrapatna
Mr Yong Bai
Dr Pengfei Zhu
Bell Labs, Lucent Technologies
Dr.Said Elnoubi
Dr.Abbas ElShamly
Alexandria University
Mr.Walaa Hamouda
Dr.Peter McLane
Queen's University
Chung-Ju Chang
Mr
Scott Shen
Dep.of Comm.Eng.of National Chiao Tung Univ., Taiwan
Mr Gwenael LE BODIC
Dr Demessie GIRMA
Dr James IRVINE
University of Strathclyde
Mr Chaohuang Zeng
Ms Louise Hoo
Dr John Cioffi
Stanford University
Dr.Mohsen Kavehrad
Dr.Junsong Li
Dr.Reinaldo Valenzuela
The Pennsylvania State University
Mr.Bjorn Hjelm
University of Colorado
Eng.Andrea Tonello
Dr.Nicola Laurenti
Prof Silvano Pupolin
University of Padova - DEI - Department of Electronics
Dr Fortunato Santucci
Dr Fabio Graziosi
Ing Valerio Di Claudio
University of L'Aquila, Dept.of Electrical Engineering
Dr Fortunato Santucci
Dr Wei Huang
Prof Vijay K.Bhargava
University of L'Aquila, Dept.of Electrical Engineering
Mr Emad Al-Susa
Prof Richard Ormondroyd
University of Bath
Mr Galileo De Obaldia
Dr Dave Grace
Mr Tim Tozer
University of York
Dr Saied Elnoubi
Dr Nawal A.El-Fishawy
Eng.Wael El-Sersy
Faculty of electronic engineering
Mr Joonyoung Cho
Mr Youhan Kim
Dr Kyungwhoon Cheun
Pohang University of Science and Technology, KOREA (ROK)
Mr Oscar Lazaro
Dr Demessie Girma
University of Strathclyde
Mr.Makoto Yoshida
Mr.Eizou Ishizu
Mr.Saito Tamio
Fujitsu Laboratories LTD.
Dr.Allen He
Mark Newbury
Lucent Technologies
Dr.Joseph Hui
Arizona State University
Mr Lei Wan
Dr Vimal Kishore Dubey
Comm Res Lab, School of EEE, Nanyang Technological Univ.
Mr Hemanth Sampath
Dr.Helmut Bolcskei
Dr.Paulraj Arogyaswami
Stanford University
Ms Hiroko Hisata
Dr Jun Horikoshi
Gunma University
Prof John Shynk
Mr Kuei-Chiang Lai
University of California, Santa Barbara
Dr Mark Beach
Mr Darren McNamara
Dr Peter Karlsson
University of Bristol
Mr Zhang Lijun
Prof Cao Zhigang
Ms Gao Chunyan
State Key Lab on Microwave and Digital Communication
Mr Udayan Dasgupta
Dr.Krishna Narayanan
Department of Electrical Engineering, Texas A&M
University,
Mr.Jeffrey Andrews
Dr Teresa Meng
Stanford University
Joo Hyun Yi
Jae Hong Lee
Shool of Electrical Engineering, Seoul National University
Mr Raphael VISOZ
Mr Antoine Berthet
Mr Patrick Tortelier
France Telecom
Dr Xue Gao
Mr Chengshu Li
Modern Communication Research Institute
Dr Javier Garcia-Frias
University of Delaware
Mr Panos Karaivazoglou
Prof Kostas Berberidis
University of Patras
Mr.Keattisak Sripimanwat
Dr.R.M.A.P.Rajatheva
Dr.Kazi Ahmed
Telecommunications program, Asian Institute of Technology.
Mr.Weiguang Hou
Dr.Hyuck Kwon
Wichita State University
Joowan Kim
Soohong Kim
Joohwan Chun
SK Telecom (IMT-2000 Development Group)
Mrs Elena-Simona Lohan
Dr Markku Renfors
Tampere University of Technology
Mr Gyongsu Lee
Sin-Chong Park
Information and Communications University
Dr David Mottier
Mr Damien Castelain
Mitsubishi Electric ITE
Mr Ayman Elezabi
Dr Alexandra Duel-Hallen
North Carolina State University
Mr Andreas Schmidbauer
Institute for Communications Engineering (LNT)
Dr.Tho Le-Ngoc
Dr.Hichem Besbes
Concordia University
Dr Anna Scaglione
Prof Sergio Barbarossa
Prof Georgios Giannakis
University of Minnesota
Dr.Ivan Howitt
Mr Neal Seidl
Dr James Richie
University of Wisconsin - Milwaukee
Mr Huaiyu Dou
Mr Xiangning Fan
Mr Guangguo Bi
Southeast University
Dr Shouxing Qu
Mr Yuan Jiang
Cadence Design Systems
Ms Yoshiko Saito
Mr Keiichi Kitagawa
Mr Mitsuru Uesugi
Matsushita Communication Industrial Co., Ltd.
Mr.Daniel Fague
Analog Devices, Inc.
Mr Gerald Lehmann
SIEMENS AG, Germany
Dr.Hanks zeng
Dr Ye (Geoffrey) Li
Dr.Jack Winters
AT&T Labs-Research
Mr Frieder Sanzi
Mr Stephan ten Brink
Institute of Telecommunications, Dep.0408
Mr Rui Alves
Dr Atilio Gameiro
Institute of Telecommunications
Mr Jibing Wang
Dr Ming Zhao
Dr ShiDong Zhou
Tsinghua University
Mr Shin Hyundong
Mr Kim Sunghwan
Mr Lee Jae Hong
Seoul National University, Institute of New Media &
Commun.
Mr Gyongsu Lee
Sin-Chong Park
Information and Communications University
Mr.Michael Lopez
Dr.Kambiz Zangi
Dr.Jung-Fu Cheng
Massachusetts Institute of Technology
Dr Jonqyin Sun
Irving Reed
Lucent Technologies
Mr Suzuki Toshinori
KDD R&D Laboratories Inc.
Prof Hideo Kobayashi
Mie University
Prof Hideo Kobayashi
Mie University
Mr.Bruce McNair
Dr.Leonard Cimini
Mr.Nelson Sollenberger
AT&T Labs - Research
Dr Babich Fulvio
Dr Vatta Francesca
Dr Deotto Lia
University of Trieste, Italy
Dr.Yeong Min Jang
Jeehwan Ahn
ETRI - Radio & Broadcasting Tech.Lab.
Eng.Fernando Jos Velez
Prof Luis Manuel Correia
University of Beira Interior
Wenye Wang
Georgia Institute of Technology
Prof Kaveh Pahlavan
WPI
Dr Francois Chin
Mr Yan Zhou
Dr Ying-Chang Liang
Centre for Wireless Communications
Mr Wen Gao
Mr Shiauhe Tsai
Dr James S.Lehnert
School of Electrical and Computer Engineering, Purdue
Univ.
Mr BEONGKU AN
New Jersey Institute of Technology
Mr Jan-Derk Bakker
Dr Ramjee Prasad
Delft University of Technology
Nicola Binucci
Maurizio Caselli
Ericsson Telecomunicazioni SpA
Mr Jae-Woo So
Dr Dong-Ho Cho
Dept.of EE, KAIST
Mr Young-uk Chung
Dr Dong-Ho Cho
Dept.of EE, KAIST
Dr Boujemaa Hatem
Dr Siala Mohamed
France Telecom CNET/DMR/IIM
Mr Satish Jamadagni
Silicon Automation Systems
Mr.Bjrn Hjelm
University of Colorado, Boulder
Dr Sangarapillai Lambotharan
Dr Davood Molkdar
Motorola
Mr Mazen Hasna
Dr.Mohamed Slim Alouini
University of Minnesota, Twin Cities
Ms.Yongyu Chang
Mr.Dacheng Yang
Mr.Wenbo Wang
Beijing University of Posts and Telecommunications
Mr.Kojiro Hamabe
NEC Corporation
MSc Sara Stefansson
PhD B.Christer V.Johansson
Allgon System AB
Mr Young-uk Chung
Dr Dong-Ho Cho
Dept.of EE, KAIST
Mr Xinjie Yang
Dr Shahram Ghaheri-Niri
Dr Rahim Tafazolli
University of Surrey
Mr.Xuemin Huang
Dr.Ulrich Behr
Prof Werner Wiesbeck
Institut fuer Hoechstfrequenztechnik und Elektronik (IHE)
Mr.Milap Majmundar
SBC Technology Resources, Inc.
Mr Zekeriya Uykan
Dr Heikki Koivo
Helsinki University of Technology, Control Engineering
Lab.
Mr Shahriar Shirvani Moghaddam
Iran University of Science & Technology (IUST)
Mr Shahriar Shirvani Moghaddam
Iran University of Science & Technology (IUST)
Mr Gerhard Bauch
Dr Naofal Al-Dhahir
Institute for Communications Engineering, Munich
University
Dr.Maurizio A Spirito
Nokia Research Center
Dr Davood Molkdar
Motorola
Mr Marjan Bozinovski
Mr Petar Popovski
Dr Gavrilovska Liljana
Institute of Telecommunications, Faculty of EE, Skopje
Mr Jahangir Sarker
Dr.Seppo Halme
Mr.Mika Rinne
Communications Laboratory, Helsinki University of
Technology
Mr Jae Hoon Chung
Mr Young Hoon Kwon
Mr Ki Hyoung Cho
Korea Advanced Institute of Science and Technology
Mr.Ji Xiang
Mr.Zhang Ping
Beijing University of Posts and Telecommunications
Lin Ma
Zhigang Rong
Nokia Research Center
Mr Chung Jaewook
Mr Jang Ilsoon
ETRI (Electronics and Telecommunications Research
Institute)
Mr Bhaskar Krishnamachari
Dr Stephen Wicker
School of Electrical Engineering, Cornell University
Dr Lia Deotto
Dr Fulvio Babich
Trieste University - Italy
Mr Wei Deng
Dr Bo Ai
Beijing Univ.of Posts& Telecommunications
Mr Christos Verikoukis
Dr Juan Olmos
Universidad Polytecnica de Catalunya
Mr Alexander M Wyglinski
Dr Steven D.Blostein
Queen's University
Mr Nobuhiko Miki
Mr Shigeru Tomisato
Dr Tadashi Matsumoto
NTT Mobile Communications Network Inc.
Mr Mikael Bergholz Knudsen
Dr Gert F.Pedersen
Dr Bo G.H.Olsson
Bosch Telecom Danmark A/S
Dr.James Zeidler
Ms.Jianxia Luo
Dr.Stephen McLaughlin
University of California, San Diego
Mr Patrick Eggers
Aalborg University, Center for PersonKommunikation
Mr Simon Armour
Dr Andy Nix
Prof Dave Bull
University of Bristol
Mr Xinmin Deng
Mr Pingzhi Fan
Institute of Mobile Communications
Ms Maria Julia Fernandez-Getino Garcia
Dr Santiago Zazo
Dr Jose M.Paez-Borrallo
Polytechnical University of Madrid
Lic Tiina Heikkinen
University of Lund, department of mathematical statistics
Dr Stephen Hurley
Dr Roger Whitaker
Dr Derek Smith
Cardiff University
Mr zihuai lin
Mr gran Malmgren
Mr johan torsner
Ericsson Radio Systems AB
Dr Lee Ha Cheol
Dr Lee Byung Seub
Yuhan College, Dept.of Information and Telecomm.
Mr Rathneswaran Vannithamby
Dr Elvino Sousa
University of Toronto
Mr.Xi Xie
Dr.Stephen Wicker
Cornell University
Dr Santiago Zazo
Dr Faouzi Bader
Dr J.M.Paez Borallo
Universidad Politecnica de Madrid-ETSI Telecomunicacion
Mr Hyudae Kim
Mr Sunghong Wie
Dr Dongho Cho
Korea Advanced Institute of Science and Technology
Dr.Pramod Varshney
Ms.Weihua Ye
Syracuse University
Mr Christian Hartmann
Mr Oliver Schlegelmilch
Munich University of Technology
Dr Yiping Wang
Dr David Paranchych
Mr Ashvin Chheda
Nortel Networks
Sriram Vishwanath
Dr
Andrea Goldsmith
Stanford Univeristy
Dr Takahiro Shoji
Mr Katsuhiko Hiramastu
Mr Osamu Kato
Matsushita Communication Ind.Co., Ltd.
Mr Ruifeng Zhao
Mr Hailin Jiang
Mr Zhenhui Tan
Modern Communication Research Institute
Mr.Masaaki Harada
Dr Masaaki Katayama
Dr Akira Ogawa
Ogawa Laboratory, Depertment of Information Electronics,
Mr Balasubramaniam Natarajan
Dr Carl Nassar
Dr Steve Shattil
Colorado State University
Mr Nilo Casimiro Ericsson
Ms Sorour Falahati
Prof Arne Svensson
Uppsala University, Signals & Systems Group
Dr Jae Lim
Dr Harold Stern
Samsung Telecommunications America, Inc.
Mr Harald Haas
Dr Steve McLaughlin
Dr Gordon Povey
The University of Edinburgh
Dr James Irvine
Mr Gwenael Le Bodic
Mr Robert Atkinson
University of Strathclyde
Mr Sekchin Chang
Dr Edward J.Powers
Dept.of Electrical and Computer Engineering
Dr Atef Abou-El-Azm
Dr Nawal A.El-Fishawy
Dr.Farid S.Farid S.Mohammed
Faculty of electronic engineering
Dr.Mohamed-Slim Alouini
Dr Andrea Goldsmith
University of Minnesota
Mr.Ali Abdi
Mr.Ali Abdi
Dr.H.Allen Barger
University of Minnesota
Mr Mattias Wennstrm
Signals & Systems Group, Uppsala University, Sweden
Dr Lorenzo Favalli
Prof Eugenio Costamagna
Mr.Marco Rizzardi
University of Pavia, Department of Electronics
Mr Andres Alayon Glazunov
Ericsson Radio Systems AB
Dr Mostafa Nofal
Faculty of electronic engineering
Mr Dimitrios Drakoulis
Mr Sofoklis Kyriazakos
Dr George Karetsos
National Technical University of Athens
Dr.Jeff Schodorf
MIT Lincoln Laboratory
Mr Juergen Maurer
Mr Dirk Didascalou
Prof Werner Wiesbeck
University of Karlsruhe (TH)
Mr.Abdul Waheed Umrani
Dr.Vimal K.Dubey
Nanyang Technological University
Mr Dongkyun KIM
Dr Chai-Keong Toh
Dr Yanghee Choi
Department of Computer Engineering,Seoul National
University
Sangwoo Cho
Joohwan Chun
Richard Roy
Korea Advanced Institute of Science and Technology
Mr Sungrae Cho
Georgia Institute of Technology
Dr Michele Luglio
Mr Marco Leo
University of Rome Tor Vergata
Mr Rene Nuesser
Dr Rodolfo Mann Pelz
Robert Bosch GmbH
Dr.James Caffery
University of Cincinnati
Mr.Zhiqiang Wu
Dr.Carl Nassar
Arnold Alagar
Colorado State University
Mr Wei Deng
Dr Bo Ai
Beijing Univ.of Posts and Telecommunications
Dr Prashant Krishnamurthy
Dr.Joseph Kabara
University of Pittsburgh
Ms Sebnem Ozer
Dr Symeon Papavassiliou
Dr Ali Akansu
New Jersey Institute of Technology
Mr Jung-hee Ryu
Dr Dong-Ho Cho
Korea Advanced Institute of Science and Technology
Dr Nawal El-fishawy
Dr Salah Khamis
Faculty of electronic enigineering
Dr Qing-An Zeng
Dr Dharma P.Agrawal
University of Cincinnati
Dr Tung Chong Wong
Dr Jon W.Mark
Dr Kee Chaing Chua
Centre for Wireless Communications, Nat'l Univ.of
Singapore
Dr.Micheal Parten
Mr.Sam Broyles
Texas Tech University
Mr Satoshi Matsuda
Prof Hiromi Okada
Information Network Laboratory, Kansai University
Mr.Mike Fitzmaurice
Mr.Mike Wyrzykowski
Toronto Transit Commision
Mr Yuichi Morioka
Mr Sota Toshiro
Dr Nakagawa Masao
Dept.of Information and Computer Science, Keio University
Dr MARC HEDDEBAUT
Mr JEAN RIOULT
Ms MARIELLE CUVELIER
INRETS - French National Institute for Transport Research
Mr Ahmad CHAMSEDDINE
Dr Marco KLINGLER
Dr Nathalie ROLLAND
INRETS
Mr MOURAD LAOUFI
Dr MARC HEDDEBAUT
Prof JEAN - MICHEL ROUVAEN
INRETS - French National Institue for Transport Research
Dr Tae-Gyu Chang
Dr Hoi D.Ha
Mr Jung G.Kim
School of Electrical Engineering, Chung-Ang University
Mr Jakka Bhasker Reddy
Mr Kurt Herremans
Ms Liesbet Van der Perre
Interuniversity Microelectronics Center (IMEC) vzw
Miss Juliette Marais
Mr Bruno Meunier
Dr Marion Berbineau
INRETS - LEOST
Dr James Irvine
Dr Farrokh Abrishamkar
University of Strathclyde
Stephen Weiss
Wayne Staley
Clifton, Weiss & Associates, Inc.
Dr.Amer Samman
Dr.Lajos Rimai
Dr.Jim McBride
Ford Motor Company
Dr Mark Ehsani
Mr Jean Yves Routex
Mr Sebastien Gay-Desharnais
Texas A&M University
Dr Micheal Parten
Dr.Jordan Berg
Dr.Timothy Maxwell
Texas Tech University
Mr KAWAMOTO DAISUKE
Dr KAWASE TETSUYA
Mr HASHIRAO MASATAKA
KEIO UNIVERSITY
Dr xuemin shen
Dr Jon w.Mark
Mr Jun Ye
University of Waterloo
Mr Timothy Harrold
Dr Andrew Nix
University of Bristol
Mr Takumi Ito
Prof Seiichi Sampei
Prof Norihiko Morinaga
Graduate School of Engineering, Osaka University
Dr Prashant Krishnamurthy
Dr Hassan Karimi
University of Pittsburgh
Mr Ulrich Vornefeld
ComNets, RWTH Aachen University of Technology
Mr Bader Faouzi
Dr Santiago Zazo
Dr J.M.Paez Borallo
Universidad Politecnica de Madrid- ETSI Telecomunicacion
Mr Yota Komoriya
Ms Mioko Tadenuma
Mr Nishino Yoshiyuki
Dept.of Information & Computer Science, Keio University
Ms Mi-Sun Do
Mr Youngjun Park
Dr Jai-Yong Lee
Yonsei University
Mr.Felipe A Cruz-Prez
Mr.Domingo Lara-Rodrguez
Dr.Mauricio Lara
Comm.Section, Elect.Eng.Dept., CINVESTAV-IPN
Mr Steven Thoen
Dr.Liesbet Van der Perre
Dr.Marc Engels
Inter-University Micro Electronics Center (IMEC)
Ms ANNA UMBERT
Dr PILAR DAZ
POLYTECHNIC UNIVERSITY OF CATALONIA (UPC)
Dr David Lee
William C.Y.Lee
Vodafone AirTouch
Dr.Hui Li
Ericsson Eurolab Deutschland GmbH
Mr jongin Kim
Dr Youngnam Han
Mr Jihwan Ahn
Information and Communications University
Mr Ioannis Psaromiligkos
Dr Stella Batalama
Dept.of Electrical Engineering, SUNY at Buffalo
Mr.Pete Boyer
Dr.Pablo Vicharelli
GTE Laboratories
Dr.Sadayuki Abeta
Dr.Hiroyuki Atarashi
Dr.Mamoru Sawahashi
NTT DoCoMo Inc.
Mr Arne Simonsson
Ericsson Erisoft AB
Dr Jos Fernandes
Eng Jos Garcia
Universidade de Aveiro, Instituto de Telecomunicaes
Dr Francis Lau
C Lee
Hong Kong Polytechnic Univeristy
Prof Richard Ormondroyd
Mr Francesco Nazzarri
Cranfield University
Dr.Ali Khayrallah
Dr.Tracy Fulghum
Dr.Dennis Hui
Ericsson, Inc.
Dr.Dale Hocevar
Dr.Alan Gatherer
Texas Instruments
Ms Yufei Wu
Dr.Brian Woerner
MPRG Lab, Virginia Tech
Dr PAUL STRAUCH
Mr Carlo Luschi
Dr Alexandr Kuzminskiy
Bell Labs, Lucent Technologies
Dr.Stefano Buzzi
Prof Vincent Poor
Princeton University
Dr Costas Georghiades
Mr Murat Uysal
Texas A&M University
Prof J R Cruz
Mr John Wustenberg
Ms Helen Xing
The University of Oklahoma
Mr M Mostofa Howlader
Dr Brian Woerner
Virginia Tech
Dr Parthapratim De
Mitsubishi Electric Information Technology Center America
Mr Marco Moretti
Dr Gerard Janssen
Delft University of Technology
Mr Marcos Katz
Dr Jari Iinatti
Savo Glisic
Centre for Wireless Communications, University of Oulu
CARLO LUSCHI
ALEXANDR KUZMINSKIY
PAUL STRAUCH
BELL LABORATORIES, LUCENT TECHNOLOGIES
Dr Yi-Pin Wang
Dr Greg Bottomley
Ericsson Inc.USA
Ms Lisa Welburn
Dr James K.Cavers
Dr Kevin W.Sowerby
Simon Fraser University
Young Ju Kim
Hwang Soo Lee
KAIST
Mr Jonas Karlsson
Prof Hideki Imai
University of Tokyo
Mr.Liqing Zhang
Dr.Michael Kaplan
McGill University
Mr Thomas Svantesson
Chalmers Univ.of Tech.
Dr Branislav Notaros
University of Massachusetts Dartmouth
Miss Jennifer Sui Ying Lee
Dr Weihua Zhuang
University of Waterloo
Ms Aylin Yener
Dr Roy D.Yates
Dr Sennur Ulukus
Wireless Information Network Laboratory, Rutgers
University
Mr.Anh Nguyen
Dr.Mary Ann Ingram
Georgia Institute of Technology
Prof Hendrik C Ferreira
Prof A J Han Vinck
Rand Afrikaans University
Dr Jari Iinattu
University of Oulu
Dr Abdulrauf Hafeez
Dr Molnar Karl
Ericsson Inc.
Dr Dongweon Yoon
Mr Kyongkuk Cho
Dr Jinsock Lee
Dept.of Info.and Comm.Eng., Taejon University
Mr.Myoungseob Lim
Chonbuk National University
Dr A S Madhukumar
Dr Francois Chin
Centre for Wireless Communications
ChongHyun Lee
Joohwan Chun
Korea Advanced Institute of Science and Technology
Mr Po-Wei Fu
Dr Kwang-Cheng Chen
Institute of Communication, National Taiwan University
Young Seok Lim
Jae Hong Lee
School of Electrical Engineering, Seoul National
University
Mr Thomas Hindelang
Dr.Tim Fingscheidt
Richard V.Cox
Institute for Communications Engineering
Dr Huseyin Arslan
Dr Karl Molnar
Dr Abdulrauf Hafeez
Ericsson Inc.
Mr Kuo-Hui Li
Dr Mary Ann Ingram
Georgia Institute of Technology
Mr Felip Riera-Palou
Dr James M Noras
University of Bradford
Mr Mikael Bergholz Knudsen
Dr Gert F.Pedersen
Bosch Telecom Danmark A/S
Prof Krzysztof Wesolowski
Mr Janusz Pochmara
POznan University of Technology
Dr Manzano Vidal
Dr Margarita Cabrera
Mr Adrian Agustn
Universitat Politcnica de Catalunya
Ms Monica Navarro
Dr Alex Grant
Institute for Telecommunications Research (UniSA)
Dr Mohamed-Slim Alouini
Dr Anna Scaglione
Dr Georgios Giannakis
University of Minnesota
Mr.Yoshitaka Hara
YRP Mobile Telecommunications KTRL Co., Ltd.
Dr.Frederick Vook
Dr.Timothy Thomas
Motorola Labs - Communication Systems Research Lab
Eunjung Kim
Dr
Dongho Cho
Korea Advanced Institute of Science and Technology
Ms Yong Lee
Ms HyunSook Kim
Dr.JooSeok Song
Yonsei University
Dr Roberto Verdone
Mr Mirko Ferracioli
Dr Velio Tralli
CSITE-CNR, University of Bologna
Mr.Sung-Shik Woo
Mr Heung-Ryeol You
Korea Telecom
Ms Yi YUAN-WU
CNET FRANCE TELECOM
Dr Ivan Fair
Ms L.F.Choy
Dr Witold Krzymien
University of Alberta
Mr Chung Ming YUEN
Mr Kim Fung TSANG
City University of Hong Kong
Dr Giridhar Mandyam
Nokia Research Center
Dr Stephen Hurley
Cardiff University
Mr Juan Manuel Romero Jerez
Ms Margarita Ruiz Garcia
Dr Antonio Diaz Estrella
University of Malaga
Soohong Kim
Joohwan Chun Chun
Korea Advanced Institute of Science and Technology
Mr Nagate Atsushi
Dr Sugano Masashi
Dr Murata Masayuki
Osaka University
Dr Nefedov Nikolai
Nokia Research Center
ANTONIO RODRIGUES
JOAO SILVA
HUGO PINTO
IST/IT - TECHNICAL University OF LISBON
Mr Young-uk Chung
Dr Dong-Ho Cho
Dept.of EE, KAIST
Dr.Hasan A Amca
Mr Ahnet Rizaner
Mr Ali Hakan Ulusoy
EMU - Department of Electrical and Electronic Engineering
Mr.Byungchan Ahn
Dr.Jung-Wan Cho
Dr.Hyunsoo Yoon
Korea Advanced Institute of Science and Technology
Dr.Jin Yang
Jinsong Lin
Vodafone AirTouch
Dr Walter Featherstone
Mr Leonardo Provvedi
Dr Davood Molkdar
Motorola
Dr Walter Featherstone
Dr Davood Molkdar
Motorola
Dr Insoo Sohn
Electronics & Telecommunication Research Institutue (ETRI)
Mr Kuenyoung Kim
Dr Youngnam Han
Information and Communication University
Dr.Srinath Hosur
Sundararajan Sriram
Texas Instruments Inc.
Dr.Hasan A Amca
Mr Ali Hakan Ulusoy
Mr Ahmet Rizaner
EMU - Department of Electrical and Electronic Engineering
Mr Min-Te Sun
Mr Kentaro Yamada
Dr Ten H.Lai
The Ohio State University
Mr.Vikram Kaul
Mr.Wenfeng Zhang
Dr.Roy Yates
Wireless Information Network Laboratory (WINLAB)
Mr Sofoklis Kyriazakos
Mr Dimitris Drakoulis
Mr Christos Kossidas
National Technical University of Athens
Mr Walter A Dos Santos
Dr Shahram Ghaheri-Niri
Dr Rahim Tafazolli
Centre for Communication Systems Research
Dr sandip sarkar
Mr tao Chen
Dr Edward Tiedemann
qualcomm incorporated
Dr Claes Tidestav
Mr Mathias Eriksson
Mr Arnaud Vedrine
Ericsson Radio Systems AB
Mr Wilson Wong
Dr Elvino Sousa
University of Toronto
mR Aditya Mohan
Mr Akshay Mohan
HFCL
Mr.Andreas Hutter
Mr.Joachim Hammerschmidt
Ms.Elisabeth de Carvalho
Technische Universitt Mnchen
Mr Zuji Mao
Dr Christos Douligeris
University of Miami
Mr Kathiravetpillai Sivanesan
Dr.W.H.Lam
Dept.of EEE, The University of Hong Kong
Dr Kwok Li
Mr Yuan Li
Nanyang Technological University
Mr Christoph Walke
Prof Bernhard Rembold
Institute of High Frequency Technology
Mr Genaro Hernndez-Valdez
Mr Felipe A.Cruz-Prez
Universidad Autnoma Metropolitana
Dr JIN KIM
SK Telecom
Dr Monia Turki-Hadj Alouane
Dr Meriem Jaidane-Saidane
Dr Sofiene Cherif
Laboratoire des Systmes de Communications
Mr Chunlong Bai
Prof Ping Zhang
Dr.Weidong Wang
Beijing University of Posts and Telecommunications
Jong Youl Lee
Young Mo Chung
Sang Uk Lee
New Media & Comm.Inst.Seoul National University
Mr C M Lo
Dr W.H.Lam
The University of Hong Kong
Dr.Young-Hoon Kim
Dr.Insoo Sohn
Electronics and Telecommunications Research Institute
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Beijing university of posts and telecommunications
Mr.Xiaodong Cai
Dr.Ali Akansu
New Jersey Institute of Technology
Mr Byung-goo Choi
Mr Yong-Wan Park
Yeungnam University
Dr Ning Kong
TRW
Mr KyungWoon JANG
Mr TaeHoon KIM
Dr YongWan Park
Yeungnam Univ.
Dr HYUK JUN OH
Stanford University
Mr Sunjin Yeom
Mr Jaehong Kim
Dr Yongwan Park
Yeungnam university, Information&Communication Engineering
Mr Manjeet Patterh
Dr Tara Kamal
Dr Balwinder Sohi
Sant Longowal Institute of Engineering and
Technology(SLIET)
Mr Chunlong Bai
Prof Ping Zhang
Dr.Weidong Wang
Beijing University of Posts and Telecommunications
Prof Woncheol Lee
Prof Yoan Shin
Prof Sungbin Im
School of Elecronic Engineering, Soongsil University
Ms.Yanjun Hu
Mr.Jinkang Zhu
Dr.Jun Gu
University of Science and Technology of China
MsC Roger Hoefel
Dr Francisco Cavalcanti
State University of Campinas - UNICAMP
Dr xuemin shen
Ms Xiaoning Yang
University of Waterloo
Dr Woo-Yong Choi
Hyundai Electronics Industries Co.Ltd.
Ms Concepcin Tllez
Ms Eva Gonzlez-Parada
Ms Margarita Ruiz-Garca
Dpto.Teconloga Electrnica, University of Mlaga
Dr Thomas Sexton
Deepa Devaraj
Nokia Research Center
Dr JIN KIM
SK Telecom
Mr Sun-ho Lee
Mr Jung-hee Ryu
Dr Dong-Ho Cho
Korea Advanced Institute of Science and Technology
Dr Woo-Yong Choi
Hyundai Electronics Industries Co.Ltd.
Ms MERIEM JAIDANE
Mr SOFIANE CHERIF
Ms YOUSRA BEN JEMAA
Ecole Nationale d'Ingnieurs de Tunis
Mr.Hwang Gyung-Ho
Mr.Cho Dong-Ho
Korea Advanced Institute of Science and Technology
Dr Peter Darwood
Mr Warren Linton
Dr Ian Oppermann
Southern Poro Communications
Dr MUN GI CHOI
Mr YINGCHUN XU
3COM CORPORATION
Mr.Sung Jin Hong
Dr.I-Tai Lu
Polytechnic University
Mr Ramon Sanchez-Perez
Dr Casajus Quiros
E.T.S.I.Telecomunicacion, Universidad Politecnica de
Madrid
Mr Goohyun Park
Mr Sukhyon Yoon
Dr Bubjoo Kang
Info.&Comm.Lab.Dept.of Elec.& Computer Eng.Yonsei
Univ.
Ms Anne Wiesler
Friedrich Jondral
Institut fuer Nachrichtentechnik
Mr.Jeffrey Lariviere
Dr.Rafik Goubran
Carleton University
Mr zhimin Ang
Mr wuyang Zhou
Mr Jinkang Zhu
University of Science and Technology of China
Mr Ramon Sanchez-Perez
Dr F.Javier Casajus-Quiros
Dr Subbarayan Pasupathy
ETSI Telecomunicacion, Universidad Politecnica de Madrid
Dr Xiaofeng Tao
Mr Ming Lei
Dr Ping Zhang
Beijing university of posts and telecommunications
Mr Liangxue Zhu
Mr Jinkang Zhu
University of Science & Technology of China
Dr bing bu
Mr XiShi Wang
Northern JiaoTong University
Mr Qingyu Miao
Mr Wenbo Wang
Mr Dacheng Yang
Beijing University of Posts and Telecommunications
Dr Davood Molkdar
Motorola
Prof Kaveh Pahlavan
WPI
Dr John Thompson
Dr Rudy Tanner
The University of Edinburgh
Mr Ulrich Rehfuess
Dr.Kolio Ivanov
Siemens AG ICN CA MR EE 6
Mr Makoto Sugita
Dr Uehara Kazuhiro
Dr Kubota Shuji
NTT Network Innovation Laboratories