TABLE OF CONTENTS
ACKNOWLEDGMENTS………...i
ABSTRACT………...ii
TABLE OF CONTENTS………...iii
LIST OF ABBREVIATIONS………...vi
LIST OF FIGURES………...vii
INTRODUCTION……….1
1. DATA TRANSMISSION AND TYPS OF NOISE IN COMMUNICATION SYSTEMS...1
1.1 Overview...1
1.2 Structure of Communication System...2
1.2.1 The Transmitter...3
1.2.2 The Channel...4
1.2.3 The Receiver...5
1.3 Channel Distortions...6
1.4 Channel Noise...7
1.4.1 White Noise...8
1.4.2 Colored Noise...10
1.4.3 Impulsive Noise...11
1.4.4 Transient Noise Pulses...13
1.4.5 Thermal Noise...14
1.4.6 Shot Noise...16
1.4.7 Electromagnetic Noise...16
1.5 The Interface of a Digital Communication System...17
1.5 Summary...18
2. STATE OF EQUALIZER DESIGN FOR CHANNEL DISTORTION...19
2.1. Overview...19
2.2 Channel Characteristics...19
2.2.1 Linear Channel………..20
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2.2.2 Non Linear channel………...21
2.3 Intersymbol Interference...24
2.4 Equalizer Design...25
2.4.1 The Linear Transversal Equalizer……….26
2.4.2 The Transversal Decision Feedback Equalizer (DFE)………..28
2.4.3 Neural Decision Feedback Equalizer………29
2.4.5 Adaptive Equalization Structures………..30
2.4.6 Direct Adaptation of the Equalizer Parameters...32
2.4.7 Indirect Adaptation of the Equalizer Parameters………..32
2.5 Structure of Channel Equalization...34
2.6 DSP-Equalizer and Interferences...37
2.7 FIR Filters...38
2.8 The Transmission Model...39
2.9 Structure Of Neural Equalization System...41
2.10 Summary...41
3. ARTIFICIAL NEURAL NETWORKS FOR CHANNEL EQUALIZATION...42
3.1 Overview ...42
3.2 Artificial Neuron ...42
3.3 Multilayer Perception ...46
3.4 Types of Artificial Neural Networks ...47
3.4.1 Networks Based on Supervised and Unsupervised Learning ...47
3.5 Back Propagation Learning Algorithm ...49
3.5.1 The Structure of Back Propagation Networks ...49
3.5.2 Back Propagation Learning Algorithm ...51
3.5.3 The Activation Function ...52
3.5.4 Feed Forward Calculation ...52
3.6 Summary………...…...53
4. SIMULATION OF NEURAL NETWORK BASED EQUALIZER.………..54
4.1 Overview………..54
4.2 Minimum and Non-minimum Phase Channels………....54
4.3 LMS Linear Equalizer………...58 iv
4.4 Simulation of Adaptive Equalizers………....61
4.4.1 Structure of adaptive equalization system………...61
4.4.2 Adaptive LMS and RLS equalizers……….64
4.5 Simulation of Neural Equalizer………...66
4.6 Simulation………..66
4.7 Summary………71
CONCLUSION………...72
REFERENCES………...73
APENDICES………...i
APPENDIX I………...i
APPENDIX II………..iv
MAIN PROGRAM FOR NEURAL NETWORK BASED EQUALIZER…………...v
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