1.
Mohammadi, Mohammadali; Mobini, Zahra; Ngo, Hien Quoc; Matthaiou, Michail
Ten Years of Research Advances in Full-Duplex Massive MIMO Journal Article
In: IEEE Transactions on Communications, vol. 73, no. 3, pp. 1756–1786, 2025, ISSN: 1558-0857.
Abstract | Links | BibTeX | Tags: Cell-free massive multiple-input multiple-output (CF-mMIMO), energy efficiency (EE), Full-duplex system, in-band full-duplex (IBFD), Interference cancellation, Massive MIMO, network-assisted IBFD CF-mMIMO (NAFD CF-mMIMO), self-interference (SI), spectral efficiency (SE), Surveys, Transceivers, Wireless networks, Wireless sensor networks
@article{mohammadi_ten_2025,
title = {Ten Years of Research Advances in Full-Duplex Massive MIMO},
author = {Mohammadali Mohammadi and Zahra Mobini and Hien Quoc Ngo and Michail Matthaiou},
url = {https://ieeexplore.ieee.org/document/10684260},
doi = {10.1109/TCOMM.2024.3464414},
issn = {1558-0857},
year = {2025},
date = {2025-03-01},
urldate = {2025-10-08},
journal = {IEEE Transactions on Communications},
volume = {73},
number = {3},
pages = {1756–1786},
abstract = {We present an overview of ongoing research endeavors focused on in-band full-duplex (IBFD) massive multiple-input multiple-output (MIMO) systems and their applications. In response to the unprecedented demands for mobile traffic in concurrent and upcoming wireless networks, a paradigm shift from conventional cellular networks to distributed communication systems becomes imperative. Cell-free massive MIMO (CF-mMIMO) emerges as a practical and scalable implementation of distributed/network MIMO systems, serving as a crucial physical layer technology for the advancement of next-generation wireless networks. This architecture inherits benefits from co-located massive MIMO and distributed systems and provides the flexibility for integration with the IBFD technology. We delineate the evolutionary trajectory of cellular networks, transitioning from conventional half-duplex multi-user MIMO networks to IBFD CF-mMIMO. The discussion extends further to the emerging paradigm of network-assisted IBFD CF-mMIMO (NAFD CF-mMIMO), serving as an energy-efficient prototype for asymmetric uplink and downlink communication services. This novel approach finds applications in dual-functionality scenarios, including simultaneous wireless power and information transmission, wireless surveillance, and integrated sensing and communications. We highlight various current use case applications, discuss open challenges, and outline future research directions aimed at fully realizing the potential of NAFD CF-mMIMO systems to meet the evolving demands of future wireless networks.},
keywords = {Cell-free massive multiple-input multiple-output (CF-mMIMO), energy efficiency (EE), Full-duplex system, in-band full-duplex (IBFD), Interference cancellation, Massive MIMO, network-assisted IBFD CF-mMIMO (NAFD CF-mMIMO), self-interference (SI), spectral efficiency (SE), Surveys, Transceivers, Wireless networks, Wireless sensor networks},
pubstate = {published},
tppubtype = {article}
}
We present an overview of ongoing research endeavors focused on in-band full-duplex (IBFD) massive multiple-input multiple-output (MIMO) systems and their applications. In response to the unprecedented demands for mobile traffic in concurrent and upcoming wireless networks, a paradigm shift from conventional cellular networks to distributed communication systems becomes imperative. Cell-free massive MIMO (CF-mMIMO) emerges as a practical and scalable implementation of distributed/network MIMO systems, serving as a crucial physical layer technology for the advancement of next-generation wireless networks. This architecture inherits benefits from co-located massive MIMO and distributed systems and provides the flexibility for integration with the IBFD technology. We delineate the evolutionary trajectory of cellular networks, transitioning from conventional half-duplex multi-user MIMO networks to IBFD CF-mMIMO. The discussion extends further to the emerging paradigm of network-assisted IBFD CF-mMIMO (NAFD CF-mMIMO), serving as an energy-efficient prototype for asymmetric uplink and downlink communication services. This novel approach finds applications in dual-functionality scenarios, including simultaneous wireless power and information transmission, wireless surveillance, and integrated sensing and communications. We highlight various current use case applications, discuss open challenges, and outline future research directions aimed at fully realizing the potential of NAFD CF-mMIMO systems to meet the evolving demands of future wireless networks.
2.
Wang, Zihao; El-Hajjar, Mohammed; Yang, Lie-Liang
Orbital Angular Momentum for Wireless Communications: Key Performance Indicators and Performance Comparison Journal Article
In: IEEE Access, vol. 13, pp. 80889–80913, 2025, ISSN: 2169-3536.
Abstract | Links | BibTeX | Tags: 6G communications, 6G mobile communication, antenna array, Antenna arrays, directivity, divergence angle, Key performance indicator, key performance indicators, Linear antenna arrays, OAM-mode, OFDM, orbital angular momentum (OAM), Orbital calculations, phased array, Phased arrays, purity, Three-dimensional displays, Wireless communication, Wireless communications, Wireless sensor networks
@article{wang_orbital_2025,
title = {Orbital Angular Momentum for Wireless Communications: Key Performance Indicators and Performance Comparison},
author = {Zihao Wang and Mohammed El-Hajjar and Lie-Liang Yang},
url = {https://ieeexplore.ieee.org/document/10990278},
doi = {10.1109/ACCESS.2025.3567732},
issn = {2169-3536},
year = {2025},
date = {2025-01-01},
urldate = {2025-10-08},
journal = {IEEE Access},
volume = {13},
pages = {80889–80913},
abstract = {Orbital angular momentum (OAM) is an intrinsic property of electromagnetic (EM) waves that has opened new possibilities for enhancing the capacity of wireless communications. Consequently, it has garnered significant attention in recent years. For wireless communications, antenna arrays are the most effective and widely studied approaches for OAM-wave generation. Various types of antenna arrays have been explored in research and development; however, a comprehensive comparison of these arrays remains lacking. This paper addresses this gap by first reviewing the various types of phased arrays that have been considered for OAM generation in the literature. Subsequently, it addresses the key performance indicators (KPIs) of the antenna arrays for OAM-wave generation. These KPIs include directivity, the largest producible OAM-mode (LPM), OAM-mode multiplexing capability, divergence angle, and mode purity. Based on the KPIs, a comparative analysis is conducted across several types of antenna arrays, including uniform square arrays (USA), uniform circular arrays (UCA), three-dimensional (3D) helical circular arrays (HCA), 3D helical circular sub-arrays (HCSA), and concentric UCAs (CUCA), under various settings. The study highlights the advantages and limitations of each antenna array type and examines how different parameters influence their performance.},
keywords = {6G communications, 6G mobile communication, antenna array, Antenna arrays, directivity, divergence angle, Key performance indicator, key performance indicators, Linear antenna arrays, OAM-mode, OFDM, orbital angular momentum (OAM), Orbital calculations, phased array, Phased arrays, purity, Three-dimensional displays, Wireless communication, Wireless communications, Wireless sensor networks},
pubstate = {published},
tppubtype = {article}
}
Orbital angular momentum (OAM) is an intrinsic property of electromagnetic (EM) waves that has opened new possibilities for enhancing the capacity of wireless communications. Consequently, it has garnered significant attention in recent years. For wireless communications, antenna arrays are the most effective and widely studied approaches for OAM-wave generation. Various types of antenna arrays have been explored in research and development; however, a comprehensive comparison of these arrays remains lacking. This paper addresses this gap by first reviewing the various types of phased arrays that have been considered for OAM generation in the literature. Subsequently, it addresses the key performance indicators (KPIs) of the antenna arrays for OAM-wave generation. These KPIs include directivity, the largest producible OAM-mode (LPM), OAM-mode multiplexing capability, divergence angle, and mode purity. Based on the KPIs, a comparative analysis is conducted across several types of antenna arrays, including uniform square arrays (USA), uniform circular arrays (UCA), three-dimensional (3D) helical circular arrays (HCA), 3D helical circular sub-arrays (HCSA), and concentric UCAs (CUCA), under various settings. The study highlights the advantages and limitations of each antenna array type and examines how different parameters influence their performance.
3.
Goay, Amus Chee Yuen; Mishra, Deepak; Matthaiou, Michail; Seneviratne, Aruna
Range Maximization by Optimizing Tag-to-Tag Cooperative Backscatter Communication Journal Article
In: IEEE Transactions on Green Communications and Networking, pp. 1–1, 2025, ISSN: 2473-2400.
Abstract | Links | BibTeX | Tags: Backscatter, Backscatter communication, cooperation, green communication, Internet of Things, Protocols, Quality of service, range maximization, Reflection coefficient, Relays, Resource management, tag-to-tag network, Throughput, time allocation, Wireless communication, Wireless sensor networks
@article{goay_range_2025,
title = {Range Maximization by Optimizing Tag-to-Tag Cooperative Backscatter Communication},
author = {Amus Chee Yuen Goay and Deepak Mishra and Michail Matthaiou and Aruna Seneviratne},
url = {https://ieeexplore.ieee.org/document/11008574},
doi = {10.1109/TGCN.2025.3570568},
issn = {2473-2400},
year = {2025},
date = {2025-01-01},
urldate = {2025-10-08},
journal = {IEEE Transactions on Green Communications and Networking},
pages = {1–1},
abstract = {Backscatter communication (BackCom) is a wireless technology that transmits information wirelessly by modulating the reflection of an incident signal, offering the advantages of low power consumption and low cost. This paper introduces a novel cooperative timing protocol in a two-tag BackCom network, where a single reader communicates with two passive backscatter tags using a cooperative scheme. These tags encode their information by modulating the backscattered signal and then transmitting it back to the reader. In the considered tag-to-tag cooperative scheme, the tag closer to the reader assists the farther tag in relaying its information, effectively mitigating the doubly near-far problem commonly experienced in BackCom systems. The primary objective is to maximize the transmission range of the farther tag by jointly optimizing the proposed time allocation scheme and reflection coefficients while meeting the spectral efficiency and energy threshold constraints for the quality of service and sustainability requirements. This article formulates a non-convex optimization problem and proposes a solution methodology that efficiently approximates the optimized solution with low complexity. Numerical simulations are presented to analyze the effects of varying energy and spectral efficiency requirements on the maximized transmission range. The results demonstrate that the proposed tag-to-tag cooperative BackCom framework provides a significant performance improvement, with an average range gain of over 30% compared to the non-cooperative scheme.},
keywords = {Backscatter, Backscatter communication, cooperation, green communication, Internet of Things, Protocols, Quality of service, range maximization, Reflection coefficient, Relays, Resource management, tag-to-tag network, Throughput, time allocation, Wireless communication, Wireless sensor networks},
pubstate = {published},
tppubtype = {article}
}
Backscatter communication (BackCom) is a wireless technology that transmits information wirelessly by modulating the reflection of an incident signal, offering the advantages of low power consumption and low cost. This paper introduces a novel cooperative timing protocol in a two-tag BackCom network, where a single reader communicates with two passive backscatter tags using a cooperative scheme. These tags encode their information by modulating the backscattered signal and then transmitting it back to the reader. In the considered tag-to-tag cooperative scheme, the tag closer to the reader assists the farther tag in relaying its information, effectively mitigating the doubly near-far problem commonly experienced in BackCom systems. The primary objective is to maximize the transmission range of the farther tag by jointly optimizing the proposed time allocation scheme and reflection coefficients while meeting the spectral efficiency and energy threshold constraints for the quality of service and sustainability requirements. This article formulates a non-convex optimization problem and proposes a solution methodology that efficiently approximates the optimized solution with low complexity. Numerical simulations are presented to analyze the effects of varying energy and spectral efficiency requirements on the maximized transmission range. The results demonstrate that the proposed tag-to-tag cooperative BackCom framework provides a significant performance improvement, with an average range gain of over 30% compared to the non-cooperative scheme.