LDPC Coded Modulations

chenpjh

Contents
Preface 1
1 Preliminary Concepts 3
1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Modeling a Communication System . . . . . . . . . . . . . . . . 3
1.3 Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.4 Error Correcting Codes . . . . . . . . . . . . . . . . . . . . . . 7
1.4.1 Block Codes . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.4.2 Stream Codes . . . . . . . . . . . . . . . . . . . . . . . . 9
1.5 Information Theory Basics . . . . . . . . . . . . . . . . . . . . . 10
1.6 The Following Chapters . . . . . . . . . . . . . . . . . . . . . . 17
2 Trellis-based Detection Techniques 19
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.2 Hard-Output and Soft-Output Detection . . . . . . . . . . . . . 19
2.2.1 The Viterbi Algorithm . . . . . . . . . . . . . . . . . . . 21
2.2.2 The Forward-Backward Algorithm . . . . . . . . . . . . 25
2.3 Optimal Detection Strategies for Channels with Memory . . . . 30
2.4 Detection of Encoded Data . . . . . . . . . . . . . . . . . . . . 32
2.4.1 Joint Detection and Decoding . . . . . . . . . . . . . . . 32
2.4.2 Separate Detection and Decoding . . . . . . . . . . . . . 33
2.4.3 Iterative Detection and Decoding . . . . . . . . . . . . . 33
2.4.4 Turbo Detection . . . . . . . . . . . . . . . . . . . . . . 35
2.5 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . 36
3 Low-Density Parity-Check Codes 37
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3.2 Description of LDPC Codes . . . . . . . . . . . . . . . . . . . . 37
3.3 Statistical Description of LDPC Codes . . . . . . . . . . . . . . 40
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CONTENTS
3.4 Decoding Algorithms for LDPC Codes . . . . . . . . . . . . . . 42
3.4.1 Sum-Product Algorithm . . . . . . . . . . . . . . . . . . 42
3.4.2 Min-Sum Algorithm . . . . . . . . . . . . . . . . . . . . 49
3.4.3 Alternative Decoding Algorithms . . . . . . . . . . . . . 53
3.5 Practical LDPC Code Design from Statistical Description . . . 53
3.6 Encoding Techniques for LDPC Codes . . . . . . . . . . . . . . 56
3.6.1 Encoding by Matrix Multiplication . . . . . . . . . . . . 56
3.6.2 Recursive Encoding and Structured Codes . . . . . . . . 58
3.7 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . 59
4 Performance Analysis Techniques 61
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.2 Monte Carlo System Simulation . . . . . . . . . . . . . . . . . . 62
4.3 Density Evolution . . . . . . . . . . . . . . . . . . . . . . . . . 68
4.4 EXIT Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
4.4.1 EXIT Curves and EXIT Charts . . . . . . . . . . . . . . 72
4.4.2 SISO Detectors and EXIT Charts . . . . . . . . . . . . 73
4.5 EXIT Charts for LDPC Codes . . . . . . . . . . . . . . . . . . 78
4.6 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . 81
5 LDPC Coded Modulations: Analysis and Design 83
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
5.2 LDPC Coded Modulation Schemes: Basics . . . . . . . . . . . . 85
5.2.1 A Graph-Based Detection/Decoding Approach . . . . . 85
5.2.2 A “Turbo” Detection/Decoding Approach . . . . . . . 86
5.3 Communication System Model . . . . . . . . . . . . . . . . . . 87
5.4 EXIT Chart-Based Performance Analysis . . . . . . . . . . . . 90
5.4.1 The First Iterations . . . . . . . . . . . . . . . . . . . . 91
5.4.2 The Asymptotic Convergence Region . . . . . . . . . . . 92
5.5 Upper and Lower Bounds on the BER . . . . . . . . . . . . . . 93
5.5.1 MI-Based Lower Bound on the BER . . . . . . . . . . . 93
5.5.2 MI-Based Upper Bound on the BER . . . . . . . . . . . 94
5.6 Code Design for LDPC Coded Modulations . . . . . . . . . . . 95
5.6.1 The Need for Optimization . . . . . . . . . . . . . . . . 96
5.6.2 Optimizing the EXIT Charts . . . . . . . . . . . . . . . 97
5.7 Code Design for Fast Decoding Convergence . . . . . . . . . . . 101
5.8 Code Design for a Target BER . . . . . . . . . . . . . . . . . . 110
5.8.1 Target BER-based LDPC Code Design for BEC . . . . 112
5.9 Code Design for Dispersive and Partial Response Channels . . 120
5.9.1 System Structure and Analysis . . . . . . . . . . . . . . 120
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CONTENTS
5.9.2 Theoretical Considerations . . . . . . . . . . . . . . . . 121
5.9.3 An ISI Channel SISO Property . . . . . . . . . . . . . . 124
5.9.4 LDPC Codes Designed for ISI channels . . . . . . . . . 124
5.9.5 Comments . . . . . . . . . . . . . . . . . . . . . . . . . . 126
5.10 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . 127
6 Memoryless Channels and LDPC Codes 129
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
6.2
6.2.1 The Start Point in EXIT Charts . . . . . . . . . . . . . 131
6.2.2 Numerical Evidence . . . . . . . . . . . . . . . . . . . . 132
6.2.3 Implications . . . . . . . . . . . . . . . . . . . . . . . . . 136
6.3 Multilevel Code Design . . . . . . . . . . . . . . . . . . . . . . 137
6.3.1 Multilevel Scheme Overview . . . . . . . . . . . . . . . . 138
6.3.2 Code Selection with the MI Rule . . . . . . . . . . . . . 140
6.4 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . 144
7 LDPC Codes and Differential Modulations 147
7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
7.2 Serial Concatenation of LDPC Codes with PSK and DE-PSK 148
7.3 Optimized LDPC Codes for PSK . . . . . . . . . . . . . . . . 152
7.4 LDPC Codes for DE-QAM . . . . . . . . . . . . . . . . . . . . 157
7.5 LDPC Codes for DE-PSK with Noncoherent Detection . . . . 159
7.6 Detection by Multiple Trellises . . . . . . . . . . . . . . . . . . 160
7.6.1 Time-Invariant Parameters . . . . . . . . . . . . . . . . 161
7.6.2 Time-Varying Parameters . . . . . . . . . . . . . . . . . 163
7.7 LDPC Coded Schemes with Detection by Multiple Trellises . . 170
7.7.1 Phase-Uncertain Channels . . . . . . . . . . . . . . . . . 170
7.7.2 Flat Fading Channels . . . . . . . . . . . . . . . . . . . 172
7.8 Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . 178
8 Final Remarks 179
List of Acronyms 193
Index 195

chenpjh

这本非较前沿，可适合研究生、博士生在做论文时参考。

chenpjh

这是一本2009年的参考书籍。

xcy20007

eetop[1].cn_LDPC Coded Modulations.pdf

chujn

下来看看,谢谢.

love80238023

下来看看,谢谢.

baoxiao

感谢楼主~！

wljizhe

谢了啊

wljizhe

谢了啊

aminexy

thank you