WIRELESS CELLULAR COMMUNICATIONS WITH ANTENNA ARRAYS

249 Pages·2003·1.5 MB·English

WIRELESS CELLULAR COMMUNICATIONS
WITH ANTENNA ARRAYS

Huaiyu Dai

A DISSERTATION
PRESENTED TO THE FACULTY
OF PRINCETON UNIVERSITY
IN CANDIDACY FOR THE DEGREE
OF DOCTOR OF PHILOSOPHY

RECOMMENDED FOR ACCEPTANCE
BY THE DEPARTMENT OF
ELECTRICAL ENGINEERING

November 2002
© Copyright by Huaiyu Dai, 2002. All rights reserved.
To my family

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Acknowledgements

I wish to express my sincere gratitude to my advisor, Professor H. Vincent Poor, for his
guidance and support throughout the course of my doctoral study. I would also like to
thank the professors of the Departments of Electrical Engineering, Operation Research
and Financial Engineering, and Mathematics, whose courses have provided the solid
background and foundation for my thesis research. Among them, I give special thanks to
Professor Stuart Schwartz and Professor S-Y. Kung for serving on my committee,
reading my work and giving me valuable comments, and to Professor Sergio Verdú and
Professor Hisashi Kobayashi for their inspiring teaching and advice.
I want to take this opportunity to thank Dr. Reinaldo Valenzuela and Dr. Justin
Chuang for summer internships at Bell Labs, Lucent Technologies, and at AT&T Labs-
Research, respectively. I also would like to thank Dr. Laurence Mailaender and Dr.
Andreas Molisch for their mentoring and collaborations during these internships. These
industry experiences have greatly benefited my research and future career.
Furthermore, I am indebted to my parents for their advice, support and love. I would
also like to acknowledge the contribution of all my former teachers for their cultivation
and encouragement. Finally, I thank my lovely baby girl for the hope and joy brought by
her, and my wife for her wordless support and selfless love.

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Abstract

Wireless cellular communications has been one of the fastest growing fields of
technology in the world. As opposed to its wireline counterparts, wireless
communications poses some unique challenges including multipath fading and co-
channel interference. Diversity techniques are overwhelmingly used in wireless
communication systems to enhance capacity, coverage and quality, among which space
diversity, i.e., diversity realized in space with antenna arrays, is favored because it does
not impose a penalty in terms of scarce spectrum resources. Under the framework of
wireless cellular communications with antenna arrays, both signal processing and
information theoretic aspects are studied in this dissertation.
The signal processing techniques investigated are, among others, space-time
processing, multiuser detection, and turbo decoding. All of these techniques exhibit near-
Shannon-limit performance with reasonable complexities in many cases, and are very
promising for next-generation communications. Specifically, various transmit diversity
and downlink beamforming techniques with power control are examined and compared
for wireless cellular communications with transmit arrays, and a range of iterative space-
time multiuser detection techniques are explored with receive arrays. Further, turbo
space-time multiuser detection techniques are employed for wireless cellular multiple-
input multiple-output (MIMO) communications, i.e., with antenna arrays on both transmit
and receive ends. Then, for multicell MIMO systems where co-channel interference is the
dominating detrimental factor, various multiuser receivers are proposed to dramatically
improve the system performance.
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Spectral efficiency of MIMO systems operating in multicell frequency-flat fading
environments is also studied. The following detectors are analyzed: a single-cell detector,
the joint optimum detector, a group linear minimum-mean-square-error (MMSE)
detector, a group MMSE successive cancellation detector, and an adaptive multiuser
detector. Large-system asymptotic (non-random) expressions for their spectral
efficiencies are developed. Some analytical and numerical results are derived based on
these expressions to gain insight into the behavior of multicell MIMO systems.
Even though wireless cellular communications constitutes the main part of this
dissertation, an application of some of the methods developed to wireline
communications is also considered. In particular, the turbo multiuser detection techniques
are applied to digital subscriber line (DSL) wireline communications to effectively
combat crosstalk, with the influence of impulse noise taken into consideration.

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Contents

ACKNOWLEDGEMENTS iv
ABSTRACT v

1 INTRODUCTION.........................................................................................................1
1.1 OVERVIEW...........................................................................................................1
1.2 DISSERTATION OUTLINE AND CONTRIBUTIONS....................................................7

2 TRANSMIT ARRAYS: DOWNLINK BEAMFORMING WITH POWER
CONTROL..................................................................................................................11
2.1 INTRODUCTION..................................................................................................11
2.2 SYSTEM MODEL.................................................................................................15
2.2.1 Multipath Channel...............................................................................................15
2.2.2 FDD Framework..................................................................................................19
2.2.3 Cellular System....................................................................................................20
2.3 POWER CONTROL/ALLOCATION ALGORITHMS..................................................21
2.3.1 Perron-Frobenius Theorem and its Applications................................................22
2.3.2 General Form of Power Control Problem...........................................................23
2.4 ARRAY SIGNAL PROCESSING.............................................................................25
2.4.1 Transmit Diversity...............................................................................................25
2.4.2 Sectorization........................................................................................................28
2.4.3 Beamforming Techniques....................................................................................29
2.4.3.1 Beam Steering..............................................................................................................31
2.4.3.2 Maximum SNR............................................................................................................32
2.4.3.3 Maximum SIR/SINR...................................................................................................32
2.4.4 Joint Power Control and Maximum SINR Beamforming.....................................33
2.5 NUMERICAL RESULTS........................................................................................36
2.5.1 Circuit-Switched System......................................................................................37
2.5.2 Packet-Switched System.......................................................................................46
2.6 SUMMARY..........................................................................................................53
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3 RECEIVE ARRAYS: ITERATIVE SPACE-TIME MULTIUSER DETECTION
.......................................................................................................................................54
3.1 INTRODUCTION..................................................................................................54
3.2 SPACE-TIME SIGNAL MODEL.............................................................................56
3.3 BATCH ITERATIVE METHODS.............................................................................60
3.3.1 Iterative Linear ST MUD.....................................................................................60
3.3.2 Iterative Nonlinear ST MUD...............................................................................63
3.3.2.1 Cholesky Iterative Decorrelating Decision-Feedback ST MUD..................................64
3.3.2.2 Multistage Interference Cancelling ST MUD..............................................................68
3.3.3 EM-based Iterative ST MUD with a New Structure............................................68
3.3.3.1 EM and SAGE Algorithm with Application to ST MUD............................................69
3.3.3.2 SAGE Iterative ST MUD with a New Structure..........................................................73
3.3.4 Numerical Results................................................................................................77
3.4 SAMPLE-BY-SAMPLE ADAPTIVE METHODS.......................................................85
3.4.1 Data-Aided ST MUD...........................................................................................85
3.4.1.1 Decentralized Adaptive MMSE ST MUD...................................................................86
3.4.1.2 Centralized Adaptive Decision-Feedback ST MUD....................................................90
3.4.1.3 Numerical Results........................................................................................................91
3.4.2 Blind ST MUD.....................................................................................................95
3.4.2.1 LCMV Blind ST MUD and its GSC Implementation..................................................95
3.4.2.2 MIN-MAX Channel Parameter Estimation..................................................................99
3.4.2.3 Robustified Blind ST MUD.......................................................................................100
3.4.2.4 Numerical Results......................................................................................................101
3.5 SUMMARY........................................................................................................104

4 MIMO SYSTEMS: TURBO SPACE-TIME MULTIUSER DETECTION........106
4.1 INTRODUCTION................................................................................................106
4.2 PROBLEM FORMULATION.................................................................................108
4.2.1 MIMO System Model.........................................................................................108
4.2.2 Cellular System Model.......................................................................................110
4.3 TURBO SPACE-TIME MULTIUSER DETECTION FOR INTRACELL COMMUNICATIONS
........................................................................................................................113
4.3.1 Receiver Structures and Diversity.....................................................................113
4.3.2 Turbo-BLAST Detection....................................................................................116
4.4 MULTIUSER DETECTION TO COMBAT INTERCELL INTERFERENCE....................124
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4.4.1 Maximum Likelihood MUD...............................................................................124
4.4.2 Linear MMSE MUD...........................................................................................124
4.4.3 Linear Channel Shortening MUD......................................................................125
4.4.4 Group IC MUD..................................................................................................126
4.5 NUMERICAL RESULTS......................................................................................126
4.5.1 Comparison of Various MUD Schemes for Intercell Interference Mitigation...126
4.5.2 Downlink Capacity of Interference-Limited MIMO..........................................134
4.5.3 Large-Scale Simulation Results.........................................................................139
4.5.3.1 NLOS Scenario..........................................................................................................140
4.5.3.2 LOS Scenario.............................................................................................................141
4.6 SUMMARY........................................................................................................142

5 SPECTRAL EFFICIENCY OF MULTICELL MIMO SYSTEMS....................145
5.1 INTRODUCTION................................................................................................145
5.2 SYSTEM MODEL...............................................................................................147
5.2.1 Single-cell and Multi-cell Communication Model.............................................147
5.2.2 Empirical Distribution of a Random Eigenvalue...............................................148
5.3 SPECTRAL EFFICIENCY OF MIMO SYSTEMS....................................................150
5.3.1 Single-Cell Detector..........................................................................................150
5.3.2 Joint Optimum Detector.....................................................................................151
5.3.3 Group Linear MMSE Detector..........................................................................153
5.3.4 Group MMSE Successive Cancellation Detector..............................................158
5.3.5 Adaptive Multiuser Detector..............................................................................162
5.4 ASYMPTOTIC STUDY........................................................................................162
5.5 SOME ANALYTICAL AND NUMERICAL RESULTS..............................................166
5.5.1 Approximate Formula........................................................................................167
5.5.2 Interference-Limited Behavior...........................................................................168
5.5.3 Adaptive Detection.............................................................................................172
5.6 SUMMARY........................................................................................................177

6 TURBO MULTIUSER DETECTION FOR DSL COMMUNICATIONS..........181
6.1 INTRODUCTION................................................................................................181
6.2 DSL SYSTEM MODEL......................................................................................183
6.3 MULTIUSER DETECTION FOR DSL...................................................................186
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6.3.1 Maximum Likelihood Multiuser Detection........................................................188
6.3.2 Interference Cancellation Multiuser Detection.................................................188
6.3.3 Robust Multiuser Detection with Impulse Noise................................................191
6.3.4 Importance Sampling Techniques for Intensive Simulations.............................193
6.4 TURBO MULTIUSER DETECTION FOR CODED DSL...........................................196
6.4.1 Turbo Decoding for Coded DMT System...........................................................199
6.5 NUMERICAL RESULTS......................................................................................201
6.5.1 Robust Multiuser Detection with Impulse Noise................................................201
6.5.2 Turbo Multiuser Detection.................................................................................205
6.6 SUMMARY........................................................................................................216

7 CONCLUSIONS AND PERSPECTIVES..............................................................218

BIBLIOGRAPHY.........................................................................................................223

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