About the Author xv
Acknowledgments xvii
Introduction xix
1 Introduction 1
1.1 Overview 1
1.2 Radio Frequency Communication 1
1.2.1 Limitations for Future RF Communication 3
1.2.1.1 Spectrum Congestion 3
1.2.1.2 Limited Bandwidth 3
1.2.1.3 Line-of-Sight Requirements 3
1.2.1.4 Signal Attenuation and Interference 4
1.2.1.5 Security Concerns 4
1.2.1.6 Energy Efficiency 4
1.3 Optical Communication 4
1.3.1 Future Opportunities for Optical Communication 5
1.3.1.1 High Data Rates 5
1.3.1.2 Low Latency 5
1.3.1.3 Large Bandwidth 5
1.3.1.4 Immunity to Electromagnetic Interference 5
1.3.1.5 Secure Communication 5
1.3.1.6 Energy Efficiency 6
1.4 Hybrid System 6
1.4.1 Scope of Hybrid Communication 6
1.4.1.1 Seamless Connectivity 7
1.4.1.2 Enhanced Reliability 7
1.4.1.3 Improved Performance 7
1.4.1.4 Flexibility and Scalability 8
1.4.1.5 Multimodal Communication 8
1.4.1.6 Advanced Applications 8
1.5 History of Visible Light Communication 8
1.5.1 Ancient Signaling Methods 8
1.5.2 Optical Telegraphs 9
1.5.3 Alexander Graham Bell’s Photophone (1880) 9
1.5.4 Invention of Light Emitting Diodes (LEDs) 9
1.5.5 Early Research into VLC (1990s–2000s) 9
1.5.6 Harald Haas and Li-Fi (2011) 9
1.5.7 Technological Advancements 9
1.5.8 Standardization Efforts 10
1.5.9 Integration with Modern Communication Systems 10
1.5.10 Current Trends and Future Prospects 10
1.6 Visible Light Communication 10
1.6.1 Problem 1 10
1.6.1.1 Current Industry Trend 11
1.6.1.2 Possible Solution 11
1.6.2 Problem 2 11
1.6.2.1 Current Industry Trend 12
1.6.2.2 Possible Solution 13
1.6.3 Opti Wave System Tool 13
References 13
2 Visible Light Communication 15
2.1 Overview 15
2.2 Background 16
2.3 VLC for Indoor Communication 17
2.4 Opportunities and Limitations 19
2.4.1 Applications 21
2.5 Modulation Techniques 22
2.5.1 On–Off Keying 22
2.5.2 Pulse Width Modulation 23
2.5.3 Pulse Position Modulation (PPM) 24
2.5.4 Orthogonal Frequency Division Multiplexing 25
2.5.5 Color Shift Keying 26
2.5.6 Optical Asymmetric Modulation 27
2.5.7 Discrete Multi-Tone (DMT) 28
2.6 Light Fidelity and Wireless Fidelity Comparison 29
2.7 VLC Transmitter and Receiver 29
2.7.1 VLC Transmitter 30
2.7.2 VLC Receiver 31
References 32
3 Radio over Fiber System 35
3.1 Overview 35
3.1.1 Direct Modulation 36
3.1.2 External Modulation 36
3.2 Radio over Fiber Link Configuration 37
3.2.1 Radio Frequency over Fiber 37
3.2.2 Intermediate Frequency over Fiber 37
3.2.3 Baseband over Fiber 37
3.2.4 Millimeter-Wave Signal Generation 38
3.2.5 Applications 39
3.2.5.1 Satellite Communication 39
3.2.5.2 Cellular Networks 39
3.2.5.3 Transportation and Vehicles 39
3.2.5.4 Visible Light Communication 40
3.3 Radio over Fiber System-Level Analysis 40
3.3.1 Encoding Formats 40
3.3.2 PIN and APD Photodiodes 40
3.4 Simulation 40
3.4.1 Result 41
3.5 Future Multifunctional RoF Home Network 41
3.5.1 Fiber to the Home (FTTH) 42
3.5.2 Multifrequency RoF System Design 45
References 47
4 Digital Coherent Integration with Radio over Fiber 51
4.1 Digital Coherent System Analysis 51
4.1.1 DP-QPSK Transmitter 52
4.1.2 Digital Coherent Optical Receiver 54
4.1.3 Optical Integration Technology 55
4.1.3.1 PLC Technology 55
4.1.3.2 Optical Semiconductor 55
4.1.3.3 High-Speed Electronic Devices 55
4.1.4 Digital Signal Processing in a Coherent Receiver 55
4.2 Software Implementation 56
4.3 Digital Coherent RoF System Analysis 58
4.3.1 Proposed System Design and Analysis 59
4.3.2 Simulation 60
References 62
5 Proposed Hybrid System for Indoor VLC 65
5.1 Overview 65
5.1.1 Backhaul Connection 66
5.1.2 Uplink Connectivity 66
5.2 Proposed System Design 67
5.2.1 OFDM Coherent RoF 67
5.2.1.1 Architecture Design 68
5.2.2 Modeling in OptiSystem 15 69
5.3 Proposed Auto Channel Switching Unit (ACSU) 73
5.3.1 Modeling of the Auto Channel Switching Unit (ACSU) 78
5.4 Feasibility Analysis 80
5.4.1 Technical Feasibility 80
5.4.2 Cost-Benefits Analysis 80
References 81
6 Proposed Indoor Hybrid System Modeling 83
6.1 Modeling of Indoor Hybrid System for VLC 83
6.2 VLC and RoF Indoor Downloading 83
6.3 Wi-Fi and RoF for Indoor Purposes 89
7 Conclusion and Future Work 91
7.1 Conclusion 91
7.2 Future Work 92
7.3 Applications of VLC in 6G and Above Communication 93
7.3.1 High-Speed Data Transfer 93
7.3.1.1 High Bandwidth 93
7.3.1.2 Spectral Efficiency 93
7.3.1.3 Short-Range Communication 93
7.3.1.4 Low Latency 93
7.3.1.5 Integration with Existing Infrastructure 93
7.3.1.6 Security and Privacy 94
7.3.1.7 Complementary to RF Technologies 94
7.3.2 Indoor Localization and Navigation 94
7.3.2.1 Precise Positioning 94
7.3.2.2 Multilayered Positioning 94
7.3.2.3 Low Latency 94
7.3.2.4 High-Density Deployment 95
7.3.2.5 Complementary to GPS 95
7.3.2.6 Integration with Smart Lighting 95
7.3.2.7 Privacy and Security 95
7.3.3 Augmented Reality (AR) and Virtual Reality (VR) 95
7.3.3.1 Low Latency Communication 95
7.3.3.2 High Bandwidth 96
7.3.3.3 Indoor Localization and Positioning 96
7.3.3.4 Interactive Projection Mapping 96
7.3.3.5 Gesture Recognition 96
7.3.3.6 Privacy and Security 96
7.3.3.7 Multiuser Collaboration 96
7.3.4 Smart Infrastructure and Internet of Things (IoT) 97
7.3.4.1 Smart Lighting Systems 97
7.3.4.2 Indoor Positioning and Navigation 97
7.3.4.3 Environmental Monitoring 97
7.3.4.4 Smart Retail and Hospitality 97
7.3.4.5 Smart Transportation 97
7.3.4.6 Industrial Automation 98
7.3.4.7 Energy Harvesting 98
7.3.5 Telecommunication/Wireless 98
7.3.5.1 Indoor Wireless Networking 98
7.3.5.2 Li-Fi 98
7.3.5.3 Last-Mile Connectivity 98
7.3.5.4 Secure Communications 99
7.3.5.5 Smart Cities 99
7.3.5.6 Augmented Reality (AR) and Location-Based Services 99
7.3.5.7 Vehicle-to-Infrastructure (V2I) Communication 99
8 The Role of AI and Machine Learning in 6G 101
8.1 Overview of AI and ML Concepts 101
8.1.1 Key AI and ML Concepts 101
8.2 Evolution of AI in Telecommunications 104
8.2.1 Early Adoption (1980s–1990s) 104
8.2.2 Growth Phase (2000s) 104
8.2.3 Modern Era (2010s) 105
8.2.4 Current Trends (2020s) 105
8.2.5 Future Directions (2030s and beyond) 106
8.3 Why AI and ML are Critical for 6G 106
8.4 Applications of AI and ML in Wireless Networks 108
8.4.1 Network Management and Optimization 108
8.4.2 Enhanced User Experience 109
8.4.3 Security and Fraud Detection 109
8.4.4 Predictive Maintenance and Fault Management 109
8.4.5 Advanced Communication Techniques 110
8.4.6 Edge Computing and IoT 110
8.5 6G and Visible Light Communication (VLC) 110
8.5.1 Ultrahigh-Speed Data Transmission 111
8.5.2 Enhanced Indoor Localization and Positioning 111
8.5.3 Secure and Resilient Communication 111
8.5.4 Energy-Efficient Networking 111
8.5.5 Overcoming RF Limitations and Interference 112
9 Future Research Directions for Visible Light Communication (VLC) in 6G Networks 113
9.1 VLC with Terahertz 113
9.1.1 Research Focus: Investigate Seamless Integration of VLC with Terahertz (THz) Communication Technologies 113
9.1.1.1 Complementary Strengths 113
9.1.1.2 Applications 114
9.1.1.3 Research Directions 115
9.2 Enhanced Modulation and Coding Schemes 115
9.2.1 Research Focus: Develop Advanced Modulation and Coding Techniques Tailored for VLC in 6G Networks 115
9.2.1.1 Key Areas of Research 116
9.3 Hybrid VLC-RF Networks 118
9.3.1 Research Focus: Explore Hybrid Visible Light Communication (VLC) and Radio Frequency (RF) Network Architectures to Enhance Both Coverage and Reliability 118
9.3.1.1 Key Points 118
9.3.1.2 Challenges 119
9.3.1.3 Potential Solutions and Approaches 119
9.3.1.4 Collaborative Communication Strategies 120
9.4 Massive MIMO and Beamforming Techniques 120
9.4.1 Research Focus: Investigate the Integration of Massive Multiple-Input Multiple-Output (MIMO) and Beamforming Techniques Within Visible Light Communication (VLC)-Enabled 6G Networks 120
9.4.1.1 Key Points 120
9.4.1.2 Challenges 121
9.4.1.3 Potential Solutions and Approaches 121
9.5 Network Slicing and Service Differentiation 122
9.5.1 Research Focus: Explore Network Slicing and Service Differentiation Mechanisms Tailored for Visible Light Communication (VLC) Networks Within the Context of 6G 122
9.5.1.1 Key Points 122
9.5.1.2 Challenges 123
9.5.1.3 Potential Solutions and Approaches 123
9.5.1.4 Application Scenarios 124
9.6 Energy-Efficient VLC Systems 124
9.6.1 Research Focus: Develop Energy-Efficient Visible Light Communication (VLC) Systems Tailored for Sustainable 6G Networks 124
9.6.1.1 Key Points 124
9.6.1.2 Challenges 125
9.6.1.3 Potential Solutions and Approaches 125
9.6.1.4 Application Scenarios 126
9.7 Security and Privacy Enhancements 127
9.7.1 Research Focus: Investigate Advanced Security and Privacy Mechanisms Specifically Designed for Visible Light Communication (VLC) in 6G Networks 127
9.7.1.1 Key Points 127
9.7.1.2 Challenges 127
9.7.1.3 Potential Solutions and Approaches 128
9.7.1.4 Application Scenarios 129
Index 131
