Reconfigurable Intelligent Surfaces for 6G and Beyond Wireless Networks
1st Edition
Published on 9. May 2025
Book
Hardback
640 pages
978-1-394-25011-0 (ISBN)
Description
New insights into trends, deployments, applications, and associated benefits of reconfigurable intelligent surfaces (RIS) in emerging wireless communication systems
Reconfigurable Intelligent Surfaces for 6G and Beyond Wireless Networks analyzes the design and applications of RIS in 6G and beyond, such as aiding efficient wireless signal transmission from the transmitter to the receiver while considering several practical constraints. In addition, the book offers advanced signal-processing algorithms to enable RIS applications in realistic environments and leverages advanced mathematical tools and machine learning algorithms to analyze RIS dynamics in evolving wireless networks.
Written in an easy-to-understand format, this book addresses the need to design energy- and spectral-efficient RIS models to address several network issues, including interference, pathloss, delay, traffic outage, etc. It also discusses critical security and privacy issues affecting all stakeholders in the wireless ecosystem, providing practical deep learning-based solutions to address these problems appropriately.
This book also addresses critical concepts, design principles, applications, and issues with RIS, shedding light on the recent progress and advancement in RIS-assisted wireless networks for 6G and beyond.
With contributions from experts and researchers from across the globe, this invaluable resource includes information on:
Emerging applications and potential use cases of reconfigurable intelligent surfaces in advanced wireless communication systems
Channel modeling and propagation measurements in RIS-based wireless communication systems
Energy and spectral efficiency and rate fairness for RIS-aided multiuser massive MIMO systems
Performance optimization of multiple RIS-assisted multiuser MIMO communication systems
Analytical phase-shift and amplitude element optimization for energy-efficient active RIS-aided massive MIMO systems
Physical layer security architecture and frameworks for RIS-aided wireless communication systems
RIS deployment in terrestrial and non-terrestrial wireless communication systems
Application of AI and ML techniques for intelligent power control in RIS-empowered wireless communication systems
Reconfigurable Intelligent Surfaces for 6G and Beyond Wireless Networks is an essential up-to-date reference on the subject for industry and academic researchers, scientists, and engineers in the fields of wireless communications, ICTs, MIMO, antennas, sensing, channel measurements, and modeling technologies, as well as engineers and professionals involved in RIS-assisted wireless networks.
Reconfigurable Intelligent Surfaces for 6G and Beyond Wireless Networks analyzes the design and applications of RIS in 6G and beyond, such as aiding efficient wireless signal transmission from the transmitter to the receiver while considering several practical constraints. In addition, the book offers advanced signal-processing algorithms to enable RIS applications in realistic environments and leverages advanced mathematical tools and machine learning algorithms to analyze RIS dynamics in evolving wireless networks.
Written in an easy-to-understand format, this book addresses the need to design energy- and spectral-efficient RIS models to address several network issues, including interference, pathloss, delay, traffic outage, etc. It also discusses critical security and privacy issues affecting all stakeholders in the wireless ecosystem, providing practical deep learning-based solutions to address these problems appropriately.
This book also addresses critical concepts, design principles, applications, and issues with RIS, shedding light on the recent progress and advancement in RIS-assisted wireless networks for 6G and beyond.
With contributions from experts and researchers from across the globe, this invaluable resource includes information on:
Emerging applications and potential use cases of reconfigurable intelligent surfaces in advanced wireless communication systems
Channel modeling and propagation measurements in RIS-based wireless communication systems
Energy and spectral efficiency and rate fairness for RIS-aided multiuser massive MIMO systems
Performance optimization of multiple RIS-assisted multiuser MIMO communication systems
Analytical phase-shift and amplitude element optimization for energy-efficient active RIS-aided massive MIMO systems
Physical layer security architecture and frameworks for RIS-aided wireless communication systems
RIS deployment in terrestrial and non-terrestrial wireless communication systems
Application of AI and ML techniques for intelligent power control in RIS-empowered wireless communication systems
Reconfigurable Intelligent Surfaces for 6G and Beyond Wireless Networks is an essential up-to-date reference on the subject for industry and academic researchers, scientists, and engineers in the fields of wireless communications, ICTs, MIMO, antennas, sensing, channel measurements, and modeling technologies, as well as engineers and professionals involved in RIS-assisted wireless networks.
More details
Language
English
Place of publication
United States
Publishing group
John Wiley & Sons Inc
Target group
Professional and scholarly
Product notice
sewn/stitched
Cloth over boards
Dimensions
Height: 229 mm
Width: 152 mm
Thickness: 35 mm
Weight
1016 gr
ISBN-13
978-1-394-25011-0 (9781394250110)
Copyright in bibliographic data and cover images is held by Nielsen Book Services Limited or by the publishers or by their respective licensors: all rights reserved.
Schweitzer Classification
Other editions
Additional editions
Agbotiname Lucky Imoize | Vinoth Babu Kumaravelu | Dinh-Thuan Do
Reconfigurable Intelligent Surfaces for 6G and Beyond Wireless Networks
E-Book
05/2025
1st Edition
Wiley
€129.99
Available for download
Agbotiname Lucky Imoize | Vinoth Babu Kumaravelu | Dinh-Thuan Do
Reconfigurable Intelligent Surfaces for 6G and Beyond Wireless Networks
E-Book
05/2025
1st Edition
Wiley
€129.99
Available for download
Persons
Agbotiname Lucky Imoize is a Lecturer in the Department of Electrical and Electronics Engineering at the University of Lagos, Nigeria.
Vinoth Babu Kumaravelu, PhD, is a Professor in the Department of Communication Engineering, School of Electronics Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, India.
Dinh-Thuan Do, PhD, is an Assistant Professor of Computer and Electrical Engineering, School of Engineering, University of Mount Union, Ohio, USA.
Vinoth Babu Kumaravelu, PhD, is a Professor in the Department of Communication Engineering, School of Electronics Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, India.
Dinh-Thuan Do, PhD, is an Assistant Professor of Computer and Electrical Engineering, School of Engineering, University of Mount Union, Ohio, USA.
Content
About the Editors xxiii
About the Contributors xxv
Preface xxxix
Acknowledgments xli
Introduction xliii
1 Reconfigurable Intelligent Surfaces-Assisted Wireless Communication Systems: Baseband Processing Perspective 1
Thiruvengadam Sundarrajan Jayaraman, Velmurugan Periyakarupan Gurusamy Sivabalan, Vinoth Babu Kumaravelu, Agbotiname Lucky Imoize, and Helen Sheeba John Kennedy
1.1 Introduction 1
1.2 RelatedWork 4
1.3 Comprehensive Overview of RIS 7
1.4 Characterization of RIS 11
1.5 Results and Discussions 21
1.6 Conclusion and Future Directions 27
2 Emerging Applications and Potential Use Cases of Reconfigurable Intelligent Surfaces in Wireless Communication Systems 33
Helen Sheeba John Kennedy, Anjana Babu Sujatha, Suganthi Evangeline Chakkaravarthy, Dipinkrishnan Rayaroth, Vinoth Babu Kumaravelu, Narushan Pillay, Arthi Murugadass, and Vishnu Vardhan Gudla
2.1 Introduction 33
2.2 Use Cases of RIS 36
2.3 RIS Applications 50
2.4 Challenges and Research Trends 59
2.5 Conclusions 61
3 Reconfigurable Intelligent Surfaces for 6G: A Comprehensive Overview and Electromagnetic Analysis 71
Suganthi Evangeline Chakkaravarthy, Dipinkrishnan Rayaroth, Vinoth Babu Kumaravelu, Thiruvengadam Sundarrajan Jayaraman, Velmurugan Periyakarupan Gurusamy Sivabalan, Vetrivel Chelian Thirumavalavan, Rajeshkumar Venkatesan, Arthi Murugadass, and Agbotiname Lucky Imoize
3.1 Introduction 71
3.2 Overview of RIS 75
3.3 EM Analysis of RIS 89
3.4 Impact of Mutual Coupling in RIS 92
3.5 Impact of Spatial Correlation in RIS 93
3.6 Results and Discussion 101
3.7 Conclusions 106
4 Spectral Efficiency and Rate Fairness for RIS-Aided Multiuser Massive MIMO System 113
Rafael Augusto Pedriali, Wilson de Souza Junior, and Taufik Abrao
4.1 Introduction 113
4.2 Fundamental Concepts 118
4.3 Methodology 136
4.4 Numerical Results 148
4.5 Conclusions 162
5 Performance Optimization of Multiple RIS-Assisted Multiuser MIMO Communication Systems 169
Francisco Ruben Castillo Soria, Roilhi Frajo Ibarra-Hernandez, Carlos Adrian Gutierrez Diaz de Leon, Abel Garcia Barrientos, Sharon Macias-Velasquez, and Jose Alberto del Puerto-Flores
5.1 Introduction 169
5.2 RelatedWork 171
5.3 N-RIS-assisted MU-MIMO System Model 173
5.4 Blind RISs and Optimized Transmission 176
5.5 System Performance Results 180
5.6 Artificial Intelligence in RIS-assisted MU-MIMO Systems 186
5.7 Future Trends, Challenges, and Opportunities 195
5.8 Conclusion 196
6 Analytical Phase Shift and Amplitude Element Optimization for Energy-Efficient Active RIS-Aided Massive MIMO Systems 201
Wilson de Souza Junior, Jose Carlos Marinello Filho, and Taufik Abrao
6.1 Introduction 201
6.2 RelatedWorks 205
6.3 General System Model for RIS-aided M-MIMO 211
6.4 Optimization Techniques 218
6.5 Problem Formulation 221
6.6 Proposed Solution 222
6.7 Numerical Results 228
6.7.1 Efficiency of the Proposed Algorithm 228
6.8 Conclusions and Perspectives 233
7 Element Grouping in IRS-Aided Wireless Communication System 243
Samarendra Nath Sur, Huu Quy Tran, and Agbotiname Lucky Imoize
7.1 Introduction 243
7.2 Element Grouping 246
7.3 Mathematical Model 252
7.4 Results 260
7.5 Conclusion and Future Scope 264
8 Reconfigurable Intelligent Surface-Empowered Non-orthogonal Multiple Access: Outage and ABER Analysis of Smart and Blind Transmissions 271
Vinoth Babu Kumaravelu, Anjana Babu Sujatha, Helen Sheeba John Kennedy, Francisco Ruben Castillo Soria, Dinh-Thuan Do, Velmurugan Periyakarupan Gurusamy Sivabalan, Thiruvengadam Sundarrajan Jayaraman, Agbotiname Lucky Imoize, Vishnu Vardhan Gudla, and Arthi Murugadass
8.1 Introduction 271
8.2 RelatedWorks 274
8.3 RIS-AP-NOMA 277
8.4 Analytical Model 278
8.5 Discussions on Simulations 285
8.6 Conclusions 296
9 Convergence of RIS with Emerging Wireless Technologies 301
Mehmet Bilim, Nuri Kapucu, Yasin Kabalci, and Vinoth Babu Kumaravelu
9.1 Introduction 301
9.2 RIS-Assisted Wireless Communication Systems 302
9.3 Theoretical Analysis of RIS-Assisted Systems 321
10 A Survey on RIS for 6G-IoT Wireless Positioning and Localization 335
Vivek Menon Unnikrishnan, Poongundran Selvaprabhu, Nivetha Baskar, Vinoth Kumar Chandra Babu, Rajeshkumar Venkatesan, Vinoth Babu Kumaravelu, Sunil Chinnadurai, and Agbotiname Lucky Imoize
10.1 Introduction 335
10.2 Role of RIS-Assisted IoT Networks inWireless Positioning and Localization 338
10.3 Localization Principles and RIS-Aided Localization Algorithms 348
10.4 State-of-the-Art Research on Positioning and Localization with the Assistance of RIS in 6G-IoT 354
10.5 Potential Challenges of RIS-Aided 6G-IoT for Wireless Positioning and Localization 362
10.6 Future Research Directions 365
10.7 Conclusions 368
11 Security and Privacy Issues in RIS-Based Wireless Communication Systems 377
Nivetha Baskar, Poongundran Selvaprabhu, Vivek Menon Unnikrishnan, Vinoth Kumar Chandra Babu, Vinoth Babu Kumaravelu, Vetriveeran Rajamani, Sunil Chinnadurai, and Md. Abdul Latif Sarker
11.1 Introduction 377
11.2 RelatedWork 380
11.3 Ensuring Security and Privacy in 6G Applications Assisted by RIS 381
11.4 Various Threats and Attacks in RIS-Supported Wireless Systems 388
11.5 Secure Physical Layer Networks for RIS-Assisted System 394
11.6 Conclusions and Future Scope 398
12 AI and ML Techniques for Intelligent Power Control in RIS-Empowered Wireless Communication Systems 405
Ammar Summaq, Mukkara Prasanna Kumar, Sunil Chinnadurai, Poongundran Selvaprabhu, Vinoth Babu Kumaravelu, and Agbotiname Lucky Imoize
12.1 Introduction 405
12.2 RelatedWork 408
12.3 DRL Algorithms for RIS-Assisted Wireless Communication Systems 413
12.4 Proposed Method for Intelligent Power Control 419
12.5 Results and Analysis 425
12.6 Discussions 426
12.7 Limitations of the Survey 427
12.8 Critical Lessons Learned 427
12.9 Conclusion 428
12.10 Future Scope 428
13 An Overview of Channel Modeling and Propagation Measurements in IRS-Based Wireless Communication Systems 435
Mukkara Prasanna Kumar, Ammar Summaq, Sunil Chinnadurai, Vinoth Babu Kumaravelu, Poongundran Selvaprabhu, Agbotiname Lucky Imoize, and Gaurav Jaiswal
13.1 Introduction 435
13.2 RelatedWork 438
13.3 IRS Technology and Its Fundamental Principles 440
13.4 Channel Modeling and Propagation Measurements for Communication Systems 441
13.5 IRS Channel Modeling 448
13.6 Limitations of the Survey 464
13.7 Critical Lessons Learned 465
13.8 Potential Challenges of Propagation Measurements and Channel Modeling 465
13.9 Conclusion and Future Scope 466
14 Deep Reinforcement Algorithms in RIS-Empowered Wireless Communication Systems 475
Dang Ngoc Thien Nguyen
14.1 Introduction 475
14.2 RelatedWorks 477
14.3 What is Deep Reinforcement Learning? 480
14.4 Deep Reinforcement Learning Algorithms for RIS-Empowered Wireless Communication Systems 489
14.5 Limitations and Key Takeaways 493
14.6 Conclusion 494
15 Examining Physical Layer Security for RIS-Aided Wireless Communication Systems 499
Tuan Minh La, Hieu Tri Nguyen, and Khoi Nguyen Phan
15.1 Introduction 499
15.2 RelatedWorks 501
15.3 Fundamentals of PLS, RIS, and IoT 504
15.4 RIS-Aided PLS 509
15.5 Mathematical Analysis of PLS in an RIS-Aided NOMA Network 516
15.6 Limitations and Key Takeaways 519
15.7 Conclusion 520
16 RIS-Empowered Terrestrial and Non-terrestrial Wireless Communication Systems 525
Unwana Macaulay Ekpe
16.1 Introduction 525
16.2 Metamaterials and Metasurfaces 527
16.3 RIS-Empowered Terrestrial Communication Systems 530
16.4 RIS-Empowered Non-Terrestrial Communication Systems 540
16.5 Lessons Learned and Future Research Direction 547
16.6 Conclusion 548
17 Energy Efficiency and Optimization of RIS-Based Wireless Communication Systems 551
Kien Ho, Minh Dang Nguyen, Minh Tuan Pham, Hung Gia Truong, and Arjun Chakravarthi Pogaku
17.1 Introduction 551
17.2 Optimization for RIS-Based Transmission 555
17.3 Cooperative RIS 559
17.4 Optimization for RIS-Assisted Beamforming 563
17.5 RIS Partitioning 571
17.6 Simulation Results of Multiple RISs Systems 574
17.7 Discussion 577
17.8 Conclusion 577
References 578
Index 583
About the Contributors xxv
Preface xxxix
Acknowledgments xli
Introduction xliii
1 Reconfigurable Intelligent Surfaces-Assisted Wireless Communication Systems: Baseband Processing Perspective 1
Thiruvengadam Sundarrajan Jayaraman, Velmurugan Periyakarupan Gurusamy Sivabalan, Vinoth Babu Kumaravelu, Agbotiname Lucky Imoize, and Helen Sheeba John Kennedy
1.1 Introduction 1
1.2 RelatedWork 4
1.3 Comprehensive Overview of RIS 7
1.4 Characterization of RIS 11
1.5 Results and Discussions 21
1.6 Conclusion and Future Directions 27
2 Emerging Applications and Potential Use Cases of Reconfigurable Intelligent Surfaces in Wireless Communication Systems 33
Helen Sheeba John Kennedy, Anjana Babu Sujatha, Suganthi Evangeline Chakkaravarthy, Dipinkrishnan Rayaroth, Vinoth Babu Kumaravelu, Narushan Pillay, Arthi Murugadass, and Vishnu Vardhan Gudla
2.1 Introduction 33
2.2 Use Cases of RIS 36
2.3 RIS Applications 50
2.4 Challenges and Research Trends 59
2.5 Conclusions 61
3 Reconfigurable Intelligent Surfaces for 6G: A Comprehensive Overview and Electromagnetic Analysis 71
Suganthi Evangeline Chakkaravarthy, Dipinkrishnan Rayaroth, Vinoth Babu Kumaravelu, Thiruvengadam Sundarrajan Jayaraman, Velmurugan Periyakarupan Gurusamy Sivabalan, Vetrivel Chelian Thirumavalavan, Rajeshkumar Venkatesan, Arthi Murugadass, and Agbotiname Lucky Imoize
3.1 Introduction 71
3.2 Overview of RIS 75
3.3 EM Analysis of RIS 89
3.4 Impact of Mutual Coupling in RIS 92
3.5 Impact of Spatial Correlation in RIS 93
3.6 Results and Discussion 101
3.7 Conclusions 106
4 Spectral Efficiency and Rate Fairness for RIS-Aided Multiuser Massive MIMO System 113
Rafael Augusto Pedriali, Wilson de Souza Junior, and Taufik Abrao
4.1 Introduction 113
4.2 Fundamental Concepts 118
4.3 Methodology 136
4.4 Numerical Results 148
4.5 Conclusions 162
5 Performance Optimization of Multiple RIS-Assisted Multiuser MIMO Communication Systems 169
Francisco Ruben Castillo Soria, Roilhi Frajo Ibarra-Hernandez, Carlos Adrian Gutierrez Diaz de Leon, Abel Garcia Barrientos, Sharon Macias-Velasquez, and Jose Alberto del Puerto-Flores
5.1 Introduction 169
5.2 RelatedWork 171
5.3 N-RIS-assisted MU-MIMO System Model 173
5.4 Blind RISs and Optimized Transmission 176
5.5 System Performance Results 180
5.6 Artificial Intelligence in RIS-assisted MU-MIMO Systems 186
5.7 Future Trends, Challenges, and Opportunities 195
5.8 Conclusion 196
6 Analytical Phase Shift and Amplitude Element Optimization for Energy-Efficient Active RIS-Aided Massive MIMO Systems 201
Wilson de Souza Junior, Jose Carlos Marinello Filho, and Taufik Abrao
6.1 Introduction 201
6.2 RelatedWorks 205
6.3 General System Model for RIS-aided M-MIMO 211
6.4 Optimization Techniques 218
6.5 Problem Formulation 221
6.6 Proposed Solution 222
6.7 Numerical Results 228
6.7.1 Efficiency of the Proposed Algorithm 228
6.8 Conclusions and Perspectives 233
7 Element Grouping in IRS-Aided Wireless Communication System 243
Samarendra Nath Sur, Huu Quy Tran, and Agbotiname Lucky Imoize
7.1 Introduction 243
7.2 Element Grouping 246
7.3 Mathematical Model 252
7.4 Results 260
7.5 Conclusion and Future Scope 264
8 Reconfigurable Intelligent Surface-Empowered Non-orthogonal Multiple Access: Outage and ABER Analysis of Smart and Blind Transmissions 271
Vinoth Babu Kumaravelu, Anjana Babu Sujatha, Helen Sheeba John Kennedy, Francisco Ruben Castillo Soria, Dinh-Thuan Do, Velmurugan Periyakarupan Gurusamy Sivabalan, Thiruvengadam Sundarrajan Jayaraman, Agbotiname Lucky Imoize, Vishnu Vardhan Gudla, and Arthi Murugadass
8.1 Introduction 271
8.2 RelatedWorks 274
8.3 RIS-AP-NOMA 277
8.4 Analytical Model 278
8.5 Discussions on Simulations 285
8.6 Conclusions 296
9 Convergence of RIS with Emerging Wireless Technologies 301
Mehmet Bilim, Nuri Kapucu, Yasin Kabalci, and Vinoth Babu Kumaravelu
9.1 Introduction 301
9.2 RIS-Assisted Wireless Communication Systems 302
9.3 Theoretical Analysis of RIS-Assisted Systems 321
10 A Survey on RIS for 6G-IoT Wireless Positioning and Localization 335
Vivek Menon Unnikrishnan, Poongundran Selvaprabhu, Nivetha Baskar, Vinoth Kumar Chandra Babu, Rajeshkumar Venkatesan, Vinoth Babu Kumaravelu, Sunil Chinnadurai, and Agbotiname Lucky Imoize
10.1 Introduction 335
10.2 Role of RIS-Assisted IoT Networks inWireless Positioning and Localization 338
10.3 Localization Principles and RIS-Aided Localization Algorithms 348
10.4 State-of-the-Art Research on Positioning and Localization with the Assistance of RIS in 6G-IoT 354
10.5 Potential Challenges of RIS-Aided 6G-IoT for Wireless Positioning and Localization 362
10.6 Future Research Directions 365
10.7 Conclusions 368
11 Security and Privacy Issues in RIS-Based Wireless Communication Systems 377
Nivetha Baskar, Poongundran Selvaprabhu, Vivek Menon Unnikrishnan, Vinoth Kumar Chandra Babu, Vinoth Babu Kumaravelu, Vetriveeran Rajamani, Sunil Chinnadurai, and Md. Abdul Latif Sarker
11.1 Introduction 377
11.2 RelatedWork 380
11.3 Ensuring Security and Privacy in 6G Applications Assisted by RIS 381
11.4 Various Threats and Attacks in RIS-Supported Wireless Systems 388
11.5 Secure Physical Layer Networks for RIS-Assisted System 394
11.6 Conclusions and Future Scope 398
12 AI and ML Techniques for Intelligent Power Control in RIS-Empowered Wireless Communication Systems 405
Ammar Summaq, Mukkara Prasanna Kumar, Sunil Chinnadurai, Poongundran Selvaprabhu, Vinoth Babu Kumaravelu, and Agbotiname Lucky Imoize
12.1 Introduction 405
12.2 RelatedWork 408
12.3 DRL Algorithms for RIS-Assisted Wireless Communication Systems 413
12.4 Proposed Method for Intelligent Power Control 419
12.5 Results and Analysis 425
12.6 Discussions 426
12.7 Limitations of the Survey 427
12.8 Critical Lessons Learned 427
12.9 Conclusion 428
12.10 Future Scope 428
13 An Overview of Channel Modeling and Propagation Measurements in IRS-Based Wireless Communication Systems 435
Mukkara Prasanna Kumar, Ammar Summaq, Sunil Chinnadurai, Vinoth Babu Kumaravelu, Poongundran Selvaprabhu, Agbotiname Lucky Imoize, and Gaurav Jaiswal
13.1 Introduction 435
13.2 RelatedWork 438
13.3 IRS Technology and Its Fundamental Principles 440
13.4 Channel Modeling and Propagation Measurements for Communication Systems 441
13.5 IRS Channel Modeling 448
13.6 Limitations of the Survey 464
13.7 Critical Lessons Learned 465
13.8 Potential Challenges of Propagation Measurements and Channel Modeling 465
13.9 Conclusion and Future Scope 466
14 Deep Reinforcement Algorithms in RIS-Empowered Wireless Communication Systems 475
Dang Ngoc Thien Nguyen
14.1 Introduction 475
14.2 RelatedWorks 477
14.3 What is Deep Reinforcement Learning? 480
14.4 Deep Reinforcement Learning Algorithms for RIS-Empowered Wireless Communication Systems 489
14.5 Limitations and Key Takeaways 493
14.6 Conclusion 494
15 Examining Physical Layer Security for RIS-Aided Wireless Communication Systems 499
Tuan Minh La, Hieu Tri Nguyen, and Khoi Nguyen Phan
15.1 Introduction 499
15.2 RelatedWorks 501
15.3 Fundamentals of PLS, RIS, and IoT 504
15.4 RIS-Aided PLS 509
15.5 Mathematical Analysis of PLS in an RIS-Aided NOMA Network 516
15.6 Limitations and Key Takeaways 519
15.7 Conclusion 520
16 RIS-Empowered Terrestrial and Non-terrestrial Wireless Communication Systems 525
Unwana Macaulay Ekpe
16.1 Introduction 525
16.2 Metamaterials and Metasurfaces 527
16.3 RIS-Empowered Terrestrial Communication Systems 530
16.4 RIS-Empowered Non-Terrestrial Communication Systems 540
16.5 Lessons Learned and Future Research Direction 547
16.6 Conclusion 548
17 Energy Efficiency and Optimization of RIS-Based Wireless Communication Systems 551
Kien Ho, Minh Dang Nguyen, Minh Tuan Pham, Hung Gia Truong, and Arjun Chakravarthi Pogaku
17.1 Introduction 551
17.2 Optimization for RIS-Based Transmission 555
17.3 Cooperative RIS 559
17.4 Optimization for RIS-Assisted Beamforming 563
17.5 RIS Partitioning 571
17.6 Simulation Results of Multiple RISs Systems 574
17.7 Discussion 577
17.8 Conclusion 577
References 578
Index 583