Article
Engineering, Civil
Bismark Okyere, Leila Musavian, Berna Ozbek, Sherif A. Busari, Jonathan Gonzalez
Summary: In this article, the resilience of Massive MIMO Physical Layer Network Coding (PNC) to jamming attacks in vehicular networks is investigated, revealing that the combination of PNC and Massive MIMO performs better in lower SNR regions against jamming attacks.
IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS
(2021)
Article
Mathematics
Shakti Raj Chopra, Akhil Gupta, Sudeep Tanwar, Calin Ovidiu Safirescu, Traian Candin Mihaltan, Ravi Sharma
Summary: This paper introduces the use of adaptive antenna grouping and multilevel space-time trellis coding scheme in a multi-user Massive MIMO system, which achieves flexible data transfer speeds, encoding gains, improved spectral efficiency, and low decoding complexity.
Article
Telecommunications
Ibrahim Elleuch, Ali Pourranjbar, Georges Kaddoum
Summary: In a multi-user wireless network, users trying to learn anti-jamming strategies may face interference, and a solution is proposed to cooperatively learn anti-jamming techniques using distributed learning algorithms. A novel distributed multi-agent reinforcement learning algorithm is introduced, where users learn each other's strategies without the need for communication, resulting in improved transmission rates and elimination of mutual interference.
IEEE COMMUNICATIONS LETTERS
(2021)
Article
Telecommunications
Ti Ti Nguyen, Kim-Khoa Nguyen
Summary: Accurate CSI estimation is crucial for beamforming in massive MIMO systems. This study proposes a pilot-partitioning protocol to address pilot contamination caused by non-orthogonal pilot training. The protocol decomposes long-length orthogonal pilots into short-length sub-pilots and regenerates orthogonal pilots using channel correlation among consecutive slots. Additionally, an AP selection framework is proposed to eliminate ineffective APs distorted by adversarial transmissions, and power control strategies are developed for system optimization.
IEEE TRANSACTIONS ON COGNITIVE COMMUNICATIONS AND NETWORKING
(2023)
Article
Telecommunications
Ali Rezaei, Abolfazl Falahati, Shayan Zargari
Summary: This paper investigates the channel estimation and power allocation problems in a multi-way massive MIMO communication system. The relay handles signal transmission in multiple-access and broadcast stages using the maximum-ratio combining process and maximum-ratio transmission method, respectively. An optimal power allocation algorithm for energy efficiency is proposed based on the derived asymptotic SINR performance, and the trade-off between spectral efficiency and energy efficiency is explored. Simulation results verify the effectiveness of the algorithm.
WIRELESS PERSONAL COMMUNICATIONS
(2023)
Article
Telecommunications
Ali Rezaei, Abolfazl Falahati, Shayan Zargari
Summary: This paper investigates a multi-way massive MIMO communication system where multiple users transmit data through a multiple-antenna amplify-and-forward relay. The relay estimates the channels of all users and applies maximum-ratio combining in a multiple-access stage with imperfect channel state estimation. Then, maximum-ratio transmission is used in the broadcast stage. The paper derives the asymptotic performance of signal-to-interference-plus-noise ratio and formulates an optimal power allocation algorithm for energy efficiency. It also examines the trade-off between spectral efficiency and energy efficiency under imperfect channel state estimation and compares the performance of the optimal power allocation algorithm with uniform power allocation.
WIRELESS PERSONAL COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Brijesh Chander Pandey, Saif Khan Mohammed, Patchava Raviteja, Yi Hong, Emanuele Viterbo
Summary: In this paper, we propose a novel OTFS based multi-user precoder at the base station (BS) and a corresponding low complexity detector (LCD) at the user terminals (UTs), allowing for separate demodulation of each DD domain information symbol at the UT. The proposed low complexity detector achieves a sum spectral efficiency close to that achieved with optimal joint demodulation at each UT as the number of BS antennas Q increases. The spectral efficiency and error rate performance of the proposed OTFS based massive MIMO precoder is significantly more robust to channel induced Doppler spread compared to OFDM based multi-user massive MIMO systems.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2021)
Article
Computer Science, Information Systems
Li You, Yufei Huang, Wen Zhong, Wenjin Wang, Xiqi Gao
Summary: This paper focuses on the design of energy efficient precoding in multi-cell massive MIMO systems with statistical channel state information (CSI) at the transmitter. An online algorithm is proposed to achieve a no-regret transmission, gradually approaching the performance of a fixed offline method with full knowledge of future CSI. The online algorithm considers distributed optimization, reduces information exchange between cells, utilizes random matrix theory and Charnes-Cooper transform to address complexity and nonconvexity issues, and applies the online gradient ascent method for power allocation based on past CSI.
SCIENCE CHINA-INFORMATION SCIENCES
(2023)
Article
Computer Science, Information Systems
Lihua Pang, Heng Zhao, Yang Zhang, Yijian Chen, Zhaohua Lu, Anyi Wang, Jiandong Li
Summary: This article focuses on resource optimization for hybrid energy harvesting massive MIMO systems, aiming to maximize system energy efficiency through renewable energy use. It introduces offline and online algorithms to address practical constraints and achieve a good balance between performance and implementation complexity.
IEEE SYSTEMS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Long Dinh Nguyen, Hoang Duong Tuan, Trung Q. Duong, H. Vincent Poor, Lajos Hanzo
Summary: The study focused on investigating the capability of mMIMO systems to support a large user-population by introducing a new time-fraction-wise beamforming technique. A new user service scheduling scheme was proposed to address the issue of serving a large number of users, especially in the presence of multi-cell interference. The study demonstrated that the numbers of users served by the multi-cell mMIMO can be doubled within a time-slot.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2021)
Article
Engineering, Electrical & Electronic
Kunlun Wang, Yong Zhou, Jun Li, Long Shi, Wen Chen, Lajos Hanzo
Summary: This paper tackles the energy-efficient task offloading problem in a massive MIMO-aided fog computing system and proposes an optimization scheme for joint task offloading and power allocation. By solving the non-convex optimization problem in two steps, the total energy consumption of the fog access node is significantly reduced with the proposed approach.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2021)
Article
Computer Science, Information Systems
Samira Mujkic, Suad Kasapovic, Mohammed Abuibaid
Summary: This paper investigates the resource optimization problem for a multi-cell massive MIMO network with load adaptive base stations, considering the impact of user location distribution variation on energy efficiency. Different coverage areas with varying user densities are modeled to represent ULD variation.
CMC-COMPUTERS MATERIALS & CONTINUA
(2022)
Article
Computer Science, Artificial Intelligence
Byung Moo Lee, Hong Yang
Summary: This article presents energy efficient scheduling and power control schemes for Massive MIMO with massive Internet of Things (IoT) connectivity. The study focuses on improving spectral efficiency (SE) and fairness by reusing reference signal (RS) and proposing a sigmoid function based power allocation scheme.
EXPERT SYSTEMS WITH APPLICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Xinjiang Xia, Dongming Wang, Junhui Zhao, Zhi Zhang, Xiaohu You
Summary: This paper investigates the joint optimization of energy harvesting and transmission in cell-free massive MIMO with network-assisted full duplexing. The proposed scheme aims to maximize energy efficiency while guaranteeing quality-of-service, energy harvesting and compressed fronthaul requirements. Two-stage strategies of energy harvesting and transceiver design are proposed, and a fractional programming-based two-tier iterative algorithm is used to solve the highly nonconvex optimization problem. Simulation results show that the proposed algorithms outperform traditional schemes.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Mahmoud Alageli, Aissa Ikhlef, Jonathon Chambers
Summary: In this paper, the ultimate severity of a concurrent spoofing-jamming un-detected attack from a full-duplex multi-antenna eavesdropper on a legitimate user equipment in a massive MIMO system is evaluated. The eavesdropper exploits its antennas to spoof and jam the legitimate user simultaneously, causing a significant decrease in the ergodic rate. The eavesdropper optimizes the power allocation and antenna subsets to minimize the ergodic rate difference.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Tan N. Nguyen, Dinh-Hieu Tran, Trinh Van Chien, Van-Duc Phan, Nhat-Tien Nguyen, Miroslav Voznak, Symeon Chatzinotas, Bjorn Ottersten, H. Vincent Poor
Summary: This article investigates the physical layer security with radio frequency energy harvesting in a simultaneous wireless information and power transfer cooperative network. A low-complexity sensor source selection scheme is proposed, and two relaying strategies are considered. Analytical expressions for the outage probability and intercept probability are derived, and simulation results show the superiority of the proposed scheme.
IEEE SENSORS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Trinh Van Chien, Eva Lagunas, Tung Hai Ta, Symeon Chatzinotas, Bjorn Ottersten
Summary: This article discusses multi-beam high throughput satellite (HTS) systems where all beams reuse the same spectrum. A novel user scheduling and power allocation design is proposed to provide guarantees in terms of the individual QoS requirements while maximizing the system throughput under a limited power budget. The effectiveness of the algorithms on GEO satellite networks is demonstrated through numerical results, showing better QoS satisfaction combined with outstanding overall system throughput.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Giovanni Geraci, David Lopez-Perez, Mohamed Benzaghta, Symeon Chatzinotas
Summary: Integrating terrestrial and non-terrestrial networks has significant implications for both technological and societal development, with potential to connect the unconnected and enhance user experience. This convergence of ground, air, and space wireless communications poses challenges for the mobile and satellite industries, requiring the establishment of a new 3D wireless network architecture. This article explores the opportunities, challenges, and research problems associated with this revolution, showcasing how terrestrial networks can be re-engineered to accommodate aerial services or complemented by non-terrestrial infrastructure.
IEEE COMMUNICATIONS MAGAZINE
(2023)
Article
Engineering, Electrical & Electronic
Steven Kisseleff, Konstantinos Ntontin, Symeon Chatzinotas
Summary: Reconfigurable intelligent surfaces (RISs) are used to improve wireless system coverage and control communication environment through signal manipulation, particularly reflection. RIS can enhance spatial diversity and signal quality via passive beamforming. This work introduces a novel concept of cable-aided distributed RIS (CRIS) that connects distant locations, enabling superior signal propagation conditions compared to current technologies.
IEEE COMMUNICATIONS MAGAZINE
(2023)
Article
Engineering, Electrical & Electronic
Xingyu Zhou, Keke Ying, Zhen Gao, Yongpeng Wu, Zhenyu Xiao, Symeon Chatzinotas, Jinhong Yuan, Bjorn Ottersten
Summary: This paper investigates the integration of grant-free non-orthogonal multiple access (GF-NOMA) paradigm with orthogonal time frequency space (OTFS) modulation for low Earth orbit (LEO) satellite-based Internet of Things (IoT) to address challenges such as long round-trip latency and severe Doppler effect. The proposed two-stage successive active terminal identification and channel estimation scheme along with a low-complexity multi-user signal detection method demonstrate superior performance compared to existing solutions in terms of ATI, CE, and SD under the mentioned challenges.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Lin Chen, Vu Nguyen Ha, Eva Lagunas, Linlong Wu, Symeon Chatzinotas, Bjorn Ottersten
Summary: Beam Hopping (BH) is a popular technique for multi-beam satellite communication system to selectively illuminate beams and focus satellite resources efficiently. The main limitation of conventional BH is the need for adjacent beam avoidance to minimize interference. This paper proposes a dynamic beam illumination scheme with selective precoding to cover high-demand areas, and presents two convexification frameworks for solving the beam illumination design problem. A greedy algorithm is also proposed to reduce complexity while maintaining good performance. Simulation results show that the proposed schemes outperform the benchmarks in terms of demand matching performance and precoding usage minimization.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2023)
Article
Computer Science, Information Systems
Ahmet M. Elbir, Symeon Chatzinotas
Summary: The Terahertz (THz) band, with its ultra-wide bandwidth and narrow beamwidth, is considered for the development of the sixth generation wireless networks. However, THz-band transmission faces challenges such as beam-splitting, where the beams generated at different subcarriers split and point in different directions. An approach called beam-split-aware orthogonal matching pursuit (BSA-OMP) is proposed to efficiently estimate the THz channel and beamformer design without additional hardware. Numerical results show that the BSA-OMP approach outperforms existing state-of-the-art techniques.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Anastasios Papazafeiropoulos, Ahmet M. Elbir, Pandelis Kourtessis, Ioannis Krikidis, Symeon Chatzinotas
Summary: Reconfigurable intelligent surface (RIS) is a cost-effective and promising solution to extend wireless signal coverage and improve performance. This paper proposes a cooperative double-RIS with simultaneously transmitting and reflecting RIS (STAR-RIS) architecture, denoted as RIS/STAR-RIS, under correlated Rayleigh fading conditions, to assist communication in a massive multiple-input multiple-output (mMIMO) setup.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Asad Mahmood, Thang Xuan Vu, Symeon Chatzinotas, Bjorn Ottersten
Summary: This paper investigates OFDMA-enabled multiple UAV communication systems for on-demand services, aiming to provide efficient resource allocation, 3D placement of UAVs, and user association matrices. The proposed iterative algorithm achieves fast convergence speed and demonstrates superior sum-rate performance compared to existing designs.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Manzoor Ahmed, Abdul Wahid, Sayed Shariq Laique, Wali Ullah Khan, Asim Ihsan, Fang Xu, Symeon Chatzinotas, Zhu Han
Summary: This article comprehensively reviews the impact of metasurfaces on sixth-generation (6G) wireless communications and focuses on the recently developed reconfigurable intelligent surface (RIS) with simultaneous transmission and reflection capabilities (STAR-RIS). The article discusses the protocols, advantages, and applications of STAR-RIS, as well as resource allocation strategies and performance evaluation measures. It also highlights the open research problems and potential future prospects in this field.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Article
Computer Science, Information Systems
Mohammed Al-Ansi, Manjur Kolhar, Essam Sourour, Symeon Chatzinotas
Summary: This study proposes biased-power allocation (Bi-PA) and shared antenna selection (SAS) as two methods to improve the effectiveness of spatial modulation integrated into layer division multiplexing (SM-LDM) in broadcasting systems. Bi-PA enhances bit error rate (BER) fairness across layers and SAS alleviates the complexity of successive interference cancellation and enhances spectral and energy efficiencies. The proposed approaches show advantages such as nearly identical BERs for both layers, significant BER reduction, and improved achievable rates.
Article
Engineering, Electrical & Electronic
Mahdis Jalali, Flor Ortiz, Eva Lagunas, Steven Kisseleff, Luis Emiliani, Symeon Chatzinotas
Summary: The number of NGSO satellite constellations is increasing, which will inevitably cause co-channel interference with GSO networks, affecting the operation of both NGSO and GSO satellites. To protect GSO systems from interference, ITU has established regulations for emitted power flux-densities from NGSO systems. We propose a joint power and tilt control strategy to maximize user demand satisfaction and ensure compliance with ITU limits, reducing interference levels and improving service continuity.
IEEE OPEN JOURNAL OF VEHICULAR TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Juan Andres Vasquez-Peralvo, Jorge Querol, Flor Ortiz, Jorge Luis Gonzalez Rios, Eva Lagunas, Victor Monzon Baeza, Gianluca Fontanesi, Luis Manuel Garces-Socorras, Juan Carlos Merlano Duncan, Symeon Chatzinotas
Summary: This paper presents an approach for beam pattern synthesis in geostationary satellite communication systems. The approach can generate beams with different beamwidths and control them independently for the two principal cuts. A weight matrix with beamforming coefficients is computed to synthesize the required beam.
Proceedings Paper
Engineering, Electrical & Electronic
Juan A. Vasquez-Peralvo, Juan Carlos Merlano Duncan, Jorge Luis Gonzalez-Rios, Symeon Chatzinotas
Summary: This paper presents the design of a miniaturized intertwined pass-band inductive frequency selective surface in a 2.5D configuration. The proposed structure shows high miniaturization capabilities and offers a wide stop-band in upper frequencies with a fractional bandwidth of 73.15%. This design can serve as a starting point for other types of structures.
2023 INTERNATIONAL WORKSHOP ON ANTENNA TECHNOLOGY, IWAT
(2023)
Article
Computer Science, Information Systems
Hayder Al-Hraishawi, Houcine Chougrani, Steven Kisseleff, Eva Lagunas, Symeon Chatzinotas
Summary: The next phase of satellite technology is characterized by the emergence of non-geostationary orbit (NGSO) satellites, which offer new communication capabilities and support for digital technologies. NGSO systems provide lower propagation delay, smaller size, and lower signal losses compared to conventional geostationary orbit (GSO) satellites, enabling latency-critical applications and improving communication speed and energy efficiency. This paper presents a comprehensive survey of state-of-the-art NGSO research, covering communication prospects, physical layer and radio access technologies, networking aspects, and system features and architectures. The paper also discusses the challenges of integrating NGSO systems with GSO and terrestrial networks, including spectrum access, regulatory issues, constellation design, resource management, and user equipment requirements. Finally, it outlines innovative research directions and new opportunities for future NGSO research.
IEEE COMMUNICATIONS SURVEYS AND TUTORIALS
(2023)
