Otfs Modulation - Ananthanarayanan Chockalingam

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Résumé :

Preface xv

Acknowledgements xvii

Acronyms xxi

1 Introduction 1

1.1 Cellular Mobile Evolution 2

1.1.1 Moore's Law Drives Rate Increase 4

1.2 Multipath Fading Channels 5

1.2.1 Frequency Domain Characterization 6

1.2.2 Time Domain Characterization 7

1.2.3 Impact of High Dopplers 9

1.2.4 Delay-Doppler Domain Characterization 12

1.2.4.1 Urban Multi-lane Scenario ? An Example 14

1.3 Communication Waveforms for Doubly Selective Channels 14

1.3.1 OTFS - A Modulation Waveform for Doubly Selective Channels 16

1.3.2 OTFS Realization - Two Approaches 16

1.4 Waveforms for Radar Sensing 17

1.4.1 OTFS for Integrated Sensing and Communication 18

1.5 Organization of the Book 19

2 Delay-Doppler Signaling and OTFS Modulation 23

2.1 Delay-Doppler Domain 28

2.2 Time and Frequency Domain Modulation 29

2.2.1 Channel Interaction of a TD Pulse 30

2.2.2 Channel Interaction of a FD Pulse 32

2.3 Delay-Doppler (DD) Domain Modulation 34

2.3.1 Origin of Quasi-periodicity 37

2.4 Channel Interaction of a DD Domain Pulse 39

2.4.1 The Channel Interaction is Predictable 40

2.4.2 The Channel Interaction is Non-fading 43

2.4.3 The Channel Interaction is Non-stationary 43

2.5 Time- and Bandwidth-Limited DD Domain Carrier Waveforms 43

2.5.1 Example in Fig. 2.17 47

2.5.2 Orthogonality of Pulsones 49

2.5.3 Optimality as Time- and Bandwidth-limited Signals 50

2.5.4 TDM as a Limiting Case 50

2.5.5 FDM as a Limiting Case 50

2.5.6 TD Pulsones Encode Wireless Channel Dynamics 50

2.5.7 The Fourier Transform as a Composition 51

2.6 Zak-OTFS Modulation and I/O Relation 51

2.6.1 Generalized Transceiver Signal Processing 52

2.6.2 Zak-OTFS Modulation 54

2.6.3 Zak-OTFS Receiver 56

2.6.4 Zak-OTFS I/O Relation 57

2.7 Predictability of the Zak-OTFS I/O Relation in the Crystalline Regime 58

2.7.1 Non-predictability of the Zak-OTFS I/O Relation in the Non-crystalline Regime 61

2.7.2 Crystalline Decomposition 62

2.7.3 Identification of Linear Time-Varying Channels 63

2.7.4 Error in Prediction of the Zak-OTFS I/O Relation 64

2.8 Matrix-vector Description of the I/O Relation 67

2.8.1 Zak-OTFS 67

2.8.2 Tdm 68

2.8.3 Fdm 69

2.9 Impact of Fading in the Crystalline Regime 70

2.10 Model-free Operation in the Crystalline Regime 73

2.10.1 Model-dependent Operation 73

2.10.2 Model-free Operation 74

2.11 Summary 77

Appendix 2.A Cascade of Two Doubly Spread Channels and Twisted Convolution 78

2.a.1 Properties of Twisted Convolution 81

Appendix 2.B Channel Action on DD Domain Signal 83

Appendix 2.C Zak Transform 84

Appendix 2.D Derivation of (2.30) and (2.31) 85

Appendix 2.E Proof of Non-overlapping Received Impulses in a-response 86

Appendix 2.F Inverse Zak Transforms 87

2.f.1 Inverse Time-Zak Transform 87

2.f.2 Derivation of (2.38) 87

2.f.3 Inverse Frequency-Zak Transform 88

Appendix 2.G Twisted Convolution Preserves Quasi-periodicity 88

Appendix 2.H Derivation of TD Pulsone Expression in (2.41) 89

Appendix 2.I Derivation of FD Pulsone Expression in (2.44) 90

Appendix 2.J TDM I/O Relation 90

2.j.1 Proof of Theorem 2.5 91

Appendix 2.K FDM I/O Relation 92

2.k.1 Proof of Theorem 2.6 93

Appendix 2.L Discrete DD Domain Signals 94

2.l.1 Impulse Signal in Discrete DD Domain 95

Appendix 2.M Derivation of Zak-OTFS Modulator Architecture 96

Appendix 2.N Derivation of Zak-O...

Biographie:
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Sommaire:

Saif Khan Mohammed, PhD, is a Professor in the Department of Electrical Engineering at IIT Delhi, India. He worked extensively in industry before transitioning to academia, and his research interests include wireless communication, signal processing, OTFS, and related subjects.

Ronny Hadani, PhD, is an Associate Professor in the Department of Mathematics, University of Texas, Austin, USA. He is the co-founder of Cohere Technologies and co-inventor of Cohere's OTFS modulation scheme. His research focuses on representation theory, harmonic analysis, and signal processing.

Ananthanarayanan Chockalingam, PhD, is a Professor in the Department of Electrical and Communication Engineering, Indian Institute of Science, Bangalore, India. He has made pioneering contributions in the area of large MIMO systems. He has vast industry experience in wireless communications....