Half-Duplex/Full-Duplex MU-mMIMO : Metamaterial-Based Large-Scale Array & Hybrid Beamforming Design

This book presents an integrated study of metamaterial-based large-scale antenna arrays and beamforming optimization for both Half-Duplex (HD) and Full-Duplex (FD) massive MIMO (mMIMO) systems. As a cornerstone of future wireless communications, mMIMO provides substantial improvements in capacity and spectral efficiency, which this book illustrates. With strategically designed beamforming, these arrays can precisely direct energy toward intended users, while effectively suppressing interference. Metamaterial structures with tunable electromagnetic properties further enhance performance by enabling compact, high-isolation antenna elements and novel interference mitigation strategies. In addition, hybrid beamforming architectures are investigated to achieve an optimal balance between system performance and hardware complexity.

The first part of this book focuses on HD MU-mMIMO. Various planar and non-planar array structures are studied through full-wave simulations and prototype measurements, considering user distributions and hardware non-idealities. Novel nulling beamforming algorithms are developed, targeting both Far-Field angular separation and Near-Field spatially separated users. Deep, precisely aligned nulls are created to effectively suppress multi-user interference to noise levels, while preserving desired signal strength.  The second part addresses FD mMIMO, where concurrent transmission and reception promise doubled spectral efficiency, but demand strong self-interference (SI) suppression. A multi-stage transmit–receive isolation framework is introduced, integrating antenna isolation, joint beamforming, and metamaterial absorber structures. By combining beam-level isolation with cancellation techniques, experimental measurements demonstrate that residual SI can be suppressed to the noise floor, thereby ensuring reliable FD mMIMO performance.

This book is intended for researchers, engineers and advanced-level students focused on advanced wireless systems, antenna innovations, and 5G-and-beyond technology development.  It is especially valuable to R&D professionals in telecommunications companies, RF/microwave design firms, or labs working on next-generation wireless networks, antennas, and full-duplex solutions. The content provides both theoretical foundations and practical design considerations for mMIMO, full-duplex architectures, and metamaterial-based antennas. It also caters to specialists in electrical engineering, wireless communications, antenna/RF design, or signal processing who seek an in-depth exploration of cutting-edge multi-antenna technologies.

Tho Le-Ngoc obtained his B.Eng. (with Distinction) in Electrical Engineering in 1976, his M.Eng. in 1978 from McGill University, Montreal, and his Ph.D. in Digital Communications in 1983 from the University of Ottawa, Canada. During 1977–1982, he was with Spar Aerospace Limited and involved in the development and design of satellite communications systems. During 1982–1985, he was an engineering manager of the Radio Group in the Department of Development Engineering of SRTelecom Inc., where he developed the new point-to-multipoint DA-TDMA/TDM Subscriber Radio System SR500. During 1985–2000, he was a professor at the Department of Electrical and Computer Engineering of Concordia University. Since 2000, he has been with the Department of Electrical and Computer Engineering of McGill University. His research interest is in the area of broadband digital communications. He is a fellow of the Institute of Electrical and Electronics Engineers (IEEE), the Engineering Institute of Canada (EIC), the Canadian Academy of Engineering (CAE), and the Royal Society of Canada (RSC). He is the recipient of the 2004 Canadian Award in Telecommunications Research and the recipient of the IEEE Canada Fessenden Award 2005. He holds a Canada Research Chair (Tier I) on Broadband Access Communications.

 Yuanzhe Gong received the B.Eng. (Hons.) and Ph.D. degrees in Electrical and Computer Engineering from McGill University, Montreal, QC, Canada, in 2020 and 2025, respectively. Since 2018, he has served as a teaching assistant in the Department of Electrical and Computer Engineering at McGill and as a research associate with the Broadband Communication Research Laboratory. He was the recipient of the McGill Engineering Doctoral Award (MEDA), the Graduate Research Enhancement and Travel Award (GREAT Award), the McGill Graduate Excellence Fellowship, the Dean’s Honour List, and the McGill Faculty of Engineering Scholarship. His research interests include wireless communications, antenna design, metamaterial-based large-scale array structures, massive MIMO, near-field communications, intelligent beamforming optimization algorithms, and full-duplex systems.

Mobeen Mahmood received his B.Sc. (Hons.) in Electrical Engineering from the University of Engineering and Technology (UET), Taxila, Pakistan in 2013; M.Sc. (Hons.) Electrical Engineering from the American University of Sharjah (AUS), Sharjah, UAE in 2019; and Ph.D. in Electrical Engineering from McGill University, Montreal, QC, Canada in 2024. From 2014 to 2017, he was with China Mobile Pakistan (CMPak), Islamabad, Pakistan. He is the recipient of AUS teaching assistantship, AUS research assistantship, Fonds de Recherche du Québec-Nature and Technologies (FRQNT), IEEE VTS Student Travel Award, IEEE Canada Vehicular Technologies Grant, McGill Graduate Research Enhancement and Travel Award (GREAT Award), McGill Graduate Excellence Fellowship, McGill Engineering Class of 1936 Fellowship, and J.W.McConnell Memorial Fellowship as part of McGill Engineering Doctoral Award (MEDA). His main research interests include massive MIMO, hybrid beamforming, UAV communications, AI-enable wireless networks, and full-duplex communications.