Introduction to Communication Systems Simulation

224 Pages·2006·2.95 MB·English

by  Maurice Schiff

Introduction to Communication
Systems Simulation
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Introduction to Communication
Systems Simulation
Maurice Schiff
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Library of Congress Cataloging-in-Publication Data
A catalog record of this book is available from the U.S. Library of Congress.
British Library Cataloguing in Publication Data
Schiff, Maurice
Introduction to communication systems simulation.
1. Telecommunications systems—Computer simulation
I. Title
621.3’82’0113
ISBN-10 1-59693-002-0
Cover design by Yekaterina Ratner
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International Standard Book Number: 1-59693-002-0
10 9 8 7 6 5 4 3 2 1
To my wife Sharon, for the many hours
I devoted to this book that I couldn’t devote to her.
Contents
Preface xiii
CHAPTER 1
Elements of a Communication System 1
1.1 The Transmitter 1
1.1.1 The Data Source 1
1.1.2 Source Encoding 1
1.1.3 Forward Error Correction 6
1.1.4 Interleaving 7
1.1.5 Baseband Filtering 8
1.1.6 Modulation 8
1.2 The Transmission Channel 8
1.2.1 Additive White Gaussian Noise 9
1.2.2 Interference 9
1.2.3 Fading 9
1.3 Receiver 10
1.3.1 Frequency Offset 10
1.3.2 Phase Offset 10
1.3.3 Timing Offset 11
1.3.4 Data Recovery 11
1.4 Conclusion 11
Selected Bibliography 11
CHAPTER 2
Linear Time Invariant Systems 13
2.1 LTI Systems 13
2.2 Fourier Transform (FT) Theory 15
2.3 The Digital Fourier Transform 17
2.4 DFT Windows 21
2.5 The Fast Fourier Transform 25
2.6 Conclusion 27
Selected Bibliography 27
CHAPTER 3
Sampling 29
3.1 The Sampling Operation 29
3.2 The Nyquist Sampling Theorem 33
vii
viii Contents
3.3 Recovering the Signal from Its Samples 38
3.4 Band-Pass Sampling 41
3.5 Conclusion 44
Selected Bibliography 45
CHAPTER 4
Filters 47
4.1 General Considerations 47
4.2 The Laplace Transform 50
4.3 Poles, Zeros, and Stability 51
4.4 The Two Worlds of a Filter 53
4.4.1 Infinite Impulse Response filters 53
4.4.2 Finite Impulse Response Filters 54
4.5 The z Transform 54
4.6 From s to z 55
4.7 Frequency Warping 58
4.8 The IIR Filter 59
4.9 General Implementation of a Filter of Form N(z)/D(z) 61
4.10 Practical Consideration in IIR Filter Simulation 62
4.11 Conclusion 63
Selected Bibliography 63
CHAPTER 5
Digital Detection 65
5.1 The Vector Channel 65
5.2 The Waveform Channel 68
5.3 The Matched Filter Receiver 69
5.4 From Signals to Vectors 73
5.5 The I, Q Vector Space 76
5.6 Conclusion 77
Selected Bibliography 77
CHAPTER 6
Modulation 79
6.1 Amplitude Modulation (MASK) 79
6.2 Frequency Modulation (MFSK) 79
6.3 Phase Modulation (MPSK) 83
6.4 π/4 DQPSK Modulation 86
6.5 Offset QPSK Modulation 86
6.6 QAM Modulation 86
6.7 MSK Modulation 88
6.8 OFDM Modulation 89
6.9 Pulse Position Modulation 92
6.10 Pulse Width Modulation 93
6.11 GSM EDGE Modulation 93
6.12 Spread Spectrum Modulation 94
6.12.1 Frequency Hopping 96
Contents ix
6.12.2 Direct Sequence Pseudo Noise 96
6.13 Conclusion 102
Selected Bibliography 102
CHAPTER 7
Demodulation 103
7.1 In-Phase (I) and Quadrature (Q) Down Conversion Process 103
7.2 Low-Pass Filtering 104
7.2.1 CIC Filter 105
7.2.2 Polyphase Filter 105
7.2.3 Half Band Filter 106
7.3 Offset Parameter Recovery 107
7.3.1 Frequency Offset 107
7.3.2 Data Timing 110
7.4 Phase/Frequency Recovery 112
7.4.1 BPSK 113
7.4.2 QPSK 114
7.4.3 Decision Feedback 115
7.5 Conclusion 115
Selected Bibliography 117
CHAPTER 8
Baseband Pulse Shaping 119
8.1 Baseband Pulse Analyses 119
8.2 The Raised Cosine Pulse 122
8.3 Intersymbol Interference and Eye Diagrams 125
8.4 The Root Raised Cosine Filter 128
8.5 Conclusion 129
Selected Bibliography 130
CHAPTER 9
Bit Error Rate Calculations 131
9.1 The BER Measurement Process 131
9.2 System Group Delay 133
9.3 E/N Calibration 135
b 0
9.3.1 Physical RF World Simulation 135
9.3.2 Standard BER Runs 137
9.4 Conclusion 137
Selected Bibliography 137
CHAPTER 10
Channel Models 139
10.1 Flat Fading 139
10.2 Rician Flat Fade 142
10.3 The Jakes Model 143
10.4 Frequency Selective Fading 144
10.5 Effects of Fading on BER Performance 146
x Contents
10.6 Mitigating Fading 148
10.6.1 Equalizers 148
10.6.2 Diversity 153
10.7 Conclusion 154
Selected Bibliography 154
CHAPTER 11
Nonlinear Amplifiers 155
11.1 Intercept and Compression Points 155
11.2 TWT 159
11.3 Spur Charts 159
11.4 Conclusion 162
Selected Bibliography 162
CHAPTER 12
Baseband Simulation 163
12.1 Basic Concept 163
12.2 Pass-Band Filtering 164
12.3 Baseband Noise 166
12.4 Conclusion 167
Selected Bibliography 167
CHAPTER 13
Ultra-Wideband Systems 169
13.1 Direct Sequence DS-UWB Systems 170
13.1.1 Scrambler 170
13.1.2 Forward Error Correction 171
13.1.3 Puncturing 171
13.1.4 Interleaver 172
13.1.5 Modulation 173
13.2 Multiband OFDM UWB-Multiband OFDM Alliance Systems 178
13.2.1 FEC Coding 180
13.2.2 Puncturing 181
13.2.3 Modulation 181
13.2.4 Carrier Modulation Frequency Agility 184
13.3 Conclusion 184
Selected Bibliography 184
APPENDIX A
Table of Laplace Transforms 185
APPENDIX B
Elements of Probability Theory and Random Variables 187
B.1 Probability Theory 187
B.1.1 Axioms of Probability 187
B.1.2 Dice Example 187
B.1.3 Conditional Probability 189