Publications (166)
Unicast-Multicast Cell-Free Massive MIMO: Gradient-Based Resource Allocation
Mustafa S. Abbas, Zahra Mobini, Hien Quoc Ngo +1
We consider a cell-free massive multiple-input multiple-output (CF-mMIMO) system with joint unicast and multi-group multicast transmissions. We derive exact closed-form expressions…
Reconfigurable Massive MIMO: Precoding Design and Channel Estimation in the Electromagnetic Domain
Keke Ying, Zhen Gao, Yu Su +3
Reconfigurable massive multiple-input multiple-output (RmMIMO), as an electronically-controlled fluid antenna system, offers increased flexibility for future communication systems…
When Cell-Free Massive MIMO Meets OTFS Modulation: The Downlink Case
Mohammadali Mohammadi, Hien Quoc Ngo, Michail Matthaiou
We provide a performance evaluation of orthogonal time frequency space (OTFS) modulation in cell-free massive MIMO (multiple-input multiple-output) systems. By leveraging the inher…
Ten Years of Research Advances in Full-Duplex Massive MIMO
Mohammadali Mohammadi, Zahra Mobini, Hien Quoc Ngo +1
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…
Uplink Analysis of Large MU-MIMO Systems With Space-Constrained Arrays in Ricean Fading
Harsh Tataria, Peter J. Smith, Michail Matthaiou +1
Closed-form approximations to the expected per-terminal signal-to-interference-plus-noise-ratio (SINR) and ergodic sum spectral efficiency of a large multiuser multiple-input multi…
Cell-Free Massive MIMO Surveillance of Multiple Untrusted Communication Links
Zahra Mobini, Hien Quoc Ngo, Michail Matthaiou +1
A cell-free massive multiple-input multiple-output (CF-mMIMO) system is considered for enhancing the monitoring performance of wireless surveillance, where a large number of distri…
Cell-Free Massive MIMO SWIPT with Beyond Diagonal Reconfigurable Intelligent Surfaces
Duc Thien Hua, Mohammadali Mohammadi, Hien Quoc Ngo +1
We investigate the integration of beyond diagonal reconfigurable intelligent surfaces (BDRISs) into cell free massive multiple input multiple output (CFmMIMO) systems to enhance si…
3-D Positioning and Environment Mapping for mmWave Communication Systems
Jie Yang, Shi Jin, Chao-Kai Wen +2
Millimeter-wave (mmWave) cloud radio access networks (CRANs) provide new opportunities for accurate cooperative localization, in which large bandwidths, large antenna arrays, and i…
How to Scale Up the Spectral Efficiency of Multi-way Massive MIMO Relaying?
Chung Duc Ho, Hien Quoc Ngo, Michail Matthaiou +1
This paper considers a decode-and-forward (DF) multi-way massive multiple-input multiple-output (MIMO) relay system where many users exchange their data with the aid of a relay sta…
Cell-Free Massive MIMO Surveillance Systems
Zahra Mobini, Hien Quoc Ngo, Michail Matthaiou +1
Wireless surveillance, in which untrusted communications links are proactively monitored by legitimate agencies, has started to garner a lot of interest for enhancing the national…
How Does Cell-Free Massive MIMO Support Multiple Federated Learning Groups?
Tung T. Vu, Hien Quoc Ngo, Thomas L. Marzetta +1
Federated learning (FL) has been considered as a promising learning framework for future machine learning systems due to its privacy preservation and communication efficiency. In b…
Channel Estimation and Hybrid Combining for Wideband Terahertz Massive MIMO Systems
Konstantinos Dovelos, Michail Matthaiou, Hien Quoc Ngo +1
Terahertz (THz) communication is widely considered as a key enabler for future 6G wireless systems. However, THz links are subject to high propagation losses and inter-symbol inter…
Millimeter Wave Communications for Future Mobile Networks
Ming Xiao, Shahid Mumtaz, Yongming Huang +8
Millimeter wave (mmWave) communications have recently attracted large research interest, since the huge available bandwidth can potentially lead to rates of multiple Gbps (gigabit…
Deep Energy Autoencoder for Noncoherent Multicarrier MU-SIMO Systems
Thien Van Luong, Youngwook Ko, Ngo Anh Vien +2
We propose a novel deep energy autoencoder (EA) for noncoherent multicarrier multiuser single-input multipleoutput (MU-SIMO) systems under fading channels. In particular, a single-…
A Hypernetwork Based Framework for Non-Stationary Channel Prediction
Guanzhang Liu, Zhengyang Hu, Lei Wang +3
In order to break through the development bottleneck of modern wireless communication networks, a critical issue is the out-of-date channel state information (CSI) in high mobility…
(Non)-Coherent MU-MIMO Block Fading Channels with Finite Blocklength and Linear Processing
Junjuan Feng, Hien Quoc Ngo, Michail Matthaiou
This paper studies the coherent and non-coherent multiuser multiple-input multiple-output (MU-MIMO) uplink system in the finite blocklength regime. The i.i.d. Gaussian codebook is…
Superdirective Antenna Pairs for Energy-Efficient Terahertz Massive MIMO
Konstantinos Dovelos, Stylianos D. Assimonis, Hien Quoc Ngo +1
Terahertz (THz) communication is widely deemed the next frontier of wireless networks owing to the abundant spectrum resources in the THz band. Whilst THz signals suffer from sever…
On the Performance of Zero-Forcing Processing in Multi-Way Massive MIMO Relay Networks
Chung Duc Ho, Hien Quoc Ngo, Michail Matthaiou +1
We consider a multi-way massive multiple-input multiple-output relay network with zero-forcing processing at the relay. By taking into account the time-division duplex protocol wit…
Hybrid Processing Design for Multipair Massive MIMO Relaying with Channel Spatial Correlation
Milad Fozooni, Hien Quoc Ngo, Michail Matthaiou +2
Massive multiple-input multiple-output (MIMO) avails of simple transceiver design which can tackle many drawbacks of relay systems in terms of complicated signal processing, latenc…
Cell-Free Massive MIMO for ISAC: Access Point Operation Mode Selection and Power Control
Mohamed Elfiatoure, Mohammadali Mohammadi, Hien Quoc Ngo +1
This paper considers a cell-free massive multipleinput multiple-output (MIMO) integrated sensing and communication (ISAC) system, where distributed MIMO access points (APs) are use…
Modular-CAPA-Based Communication Systems: Joint Activation and Beamforming Design
Mengyu Qian, Xidong Mu, Li You +1
The paper studies a modular continuous aperture array (CAPA) system where only selected sub‑apertures are activated, and proposes joint activation and beamforming designs to maximi…
A New Look at Dual-Hop Relaying: Performance Limits with Hardware Impairments
Emil Björnson, Michail Matthaiou, Mérouane Debbah
Physical transceivers have hardware impairments that create distortions which degrade the performance of communication systems. The vast majority of technical contributions in the…
Measurement-Based Small-Scale Channel Model for Sub-6 GHz RIS-Assisted Communications
Jian Sang, Jifeng Lan, Mingyong Zhou +6
Reconfigurable intelligent surfaces (RISs) have attracted increasing interest from both academia and industry, thanks to their unique features on controlling electromagnetic (EM) w…
Massive MIMO with Multi-Antenna Users under Jointly Correlated Ricean Fading
Konstantinos Dovelos, Michail Matthaiou, Hien Quoc Ngo +1
We study the uplink performance of massive multiple-input multiple-output (MIMO) when users are equipped with multiple antennas. To this end, we consider a generalized channel mode…
Network-Assisted Full-Duplex Cell-Free Massive MIMO Systems Under Infeasible Circumstances
Trinh Van Chien, Bui Trong Duc, Mohammadali Mohammadi +2
Cell-free massive multiple-input multiple-output is a potential candidate for future networks with pervasive connectivity by utilizing coherent joint transmission and distributed a…
Hybrid Millimeter-Wave Systems: A Novel Paradigm for HetNets
Hani Mehrpouyan, Michail Matthaiou, Rui Wang +2
Heterogeneous Networks (HetNets) are known to enhance the bandwidth efficiency and throughput of wireless networks by more effectively utilizing the network resources. However, the…
Dimensional Scaling Laws for Continuous Fluid Antenna Systems
Peter J. Smith, Amy S. Inwood, Michail Matthaiou +1
Consider the signal-to-noise ratio (SNR) of a continuous fluid antenna system (CFAS) operating over a Rayleigh fading channel. In this paper, we extend traditional system assumptio…
Cell-Free Massive MIMO SWIPT with Beyond Diagonal Reconfigurable Intelligent Surfaces
Thien Duc Hua, Mohammadali Mohammadi, Hien Quoc Ngo +1
This paper investigates the integration of beyond-diagonal reconfigurable intelligent surfaces (BD-RISs) into cell-free massive multiple-input multiple-output (CF-mMIMO) systems, f…
Multiple-Target Detection in Cell-Free Massive MIMO-Assisted ISAC
Mohamed Elfiatoure, Mohammadali Mohammadi, Hien Quoc Ngo +2
We propose a distributed implementation for integrated sensing and communication (ISAC) backed by a massive multiple input multiple output (CF-mMIMO) architecture without cells. Di…
Time-Domain Channel Measurements and Small-Scale Fading Characterization for RIS-Assisted Wireless Communication Systems
Yanqing Ren, Mingyong Zhou, Xiaokun Teng +5
Reconfigurable intelligent surfaces (RISs) have attracted extensive attention from industry and academia. In RIS-assisted wireless communication systems, practical channel measurem…
Optimized Energy Harvesting in Cell-Free Massive MIMO Using Markov Process Evolution
Muhammad Zeeshan Mumtaz, Mohammadali Mohammadi, Hien Quoc Ngo +1
This paper investigates a discrete energy state transition model for energy harvesting (EH) in cell-free massive multiple-input-multiple-output (CF-mMIMO) networks. A Markov chain-…
Joint User Association and Power Control for Cell-Free Massive MIMO
Chongzheng Hao, Tung Thanh Vu, Hien Quoc Ngo +4
This work proposes novel approaches that jointly design user equipment (UE) association and power control (PC) in a downlink user-centric cell-free massive multiple-input multiple-…
Cell-Free Massive MIMO-Based Physical-Layer Authentication
Isabella W. G. da Silva, Zahra Mobini, Hien Quoc Ngo +1
In this paper, we exploit the cell-free massive multiple-input multiple-output (CF-mMIMO) architecture to design a physical-layer authentication (PLA) framework that can simultaneo…
STAR-RIS-Aided Cell-Free Massive MIMO with Imperfect Hardware
Zeping Sui, Hien Quoc Ngo, Michail Matthaiou
This paper considers a simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS)-aided cell-free massive multiple-input multiple-output (CF-mMIMO) sy…
Superdirective Arrays with Finite-Length Dipoles: Modeling and New Perspectives
Konstantinos Dovelos, Stylianos D. Assimonis, Hien Quoc Ngo +1
Dense arrays can facilitate the integration of multiple antennas into finite volumes. In addition to the compact size, sub-wavelength spacing enables superdirectivity for endfire o…
Uplink Performance Analysis of Multicell MU-MIMO Systems with ZF Receivers
Hien Quoc Ngo, Michail Matthaiou, Trung Q. Duong +1
We consider the uplink of a multicell multiuser multiple-input multiple-output system where the channel experiences both small and large-scale fading. The data detection is done by…
Spectral Efficiency Analysis of Near-Field Holographic MIMO over Ricean Fading Channels
Mengyu Qian, Xidong Mu, Li You +2
With the denser distribution of antenna elements, stronger mutual coupling effects would kick in among antenna elements, which would eventually affect the communication performance…
Impact of Residual Transmit RF Impairments on Training-Based MIMO Systems
Xinlin Zhang, Michail Matthaiou, Mikael Coldrey +1
Radio-frequency (RF) impairments, that exist intimately in wireless communications systems, can severely degrade the performance of traditional multiple-input multiple-output (MIMO…
Distributed Near-Field Channel Estimation for U6G XL-MIMO Systems under Beam Squint
Zhizheng Lu, Yu Han, Xiao Li +2
Since the beam squint and near-field effects both inherently exist in upper-6 GHz (U6G) extremely large-scale multiple-input multiple-output (XL-MIMO) systems, wideband near-field…
Large intelligent surface (LIS)-based communications: New features and system layouts
Jide Yuan, Hien Quoc Ngo, Michail Matthaiou
The concept of large intelligent surface (LIS)-based communication has recently attracted increasing research attention, where a LIS is considered as an antenna array whose entire…
Anti-Malicious ISAC Using Proactive Monitoring
Zonghan Wang, Zahra Mobini, Hien Quoc Ngo +1
In this paper, we investigate proactive monitoring to mitigate malicious activities in integrated sensing and communication (ISAC) systems. Our focus is on a scenario where a cell-…
Massive MIMO with Optimal Power and Training Duration Allocation
Hien Quoc Ngo, Michail Matthaiou, Erik G. Larsson
We consider the uplink of massive multicell multiple-input multiple-output systems, where the base stations (BSs), equipped with massive arrays, serve simultaneously several termin…
Spectral Efficiency Analysis of Multi-Cell Massive MIMO Systems with Ricean Fading
Pei Liu, Kai Luo, Da Chen +2
This paper investigates the spectral efficiency of multi-cell massive multiple-input multiple-output systems with Ricean fading that utilize the linear maximal-ratio combining dete…
Cell-Free Full-Duplex Communication -- An Overview
Diluka Galappaththige, Mohammadali Mohammadi, Hien Quoc Ngo +2
Cell-free (CF) architecture and full-duplex (FD) communication are leading candidates for next-generation wireless networks. The CF framework removes cell boundaries in traditional…
Intelligent Reflecting Surface-Aided Wideband THz Communications: Modeling and Analysis
Konstantinos Dovelos, Stylianos D. Assimonis, Hien Quoc Ngo +2
In this paper, we study the performance of wideband terahertz (THz) communications assisted by an intelligent reflecting surface (IRS). Specifically, we first introduce a generaliz…
Performance Analysis and Optimization of STAR-RIS-Aided Cell-Free Massive MIMO Systems Relying on Imperfect Hardware
Zeping Sui, Hien Quoc Ngo, Michail Matthaiou +1
Simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS)-aided cell-free massive multiple-input multiple-output (CF-mMIMO) systems are investigated…
Impact of Line-of-Sight and Unequal Spatial Correlation on Uplink MU-MIMO Systems
Harsh Tataria, Peter J. Smith, Larry J. Greenstein +2
Closed-form approximations of the expected per-terminal signal-to-interference-plus-noise-ratio (SINR) and ergodic sum spectral efficiency of a multiuser multiple-input multiple-ou…
Hybrid centralized-distributed precoding in fronthaul-constrained CF-mMIMO systems
Zahra Mobini, Hien Quoc Ngo, Ardavan Rahimian +4
We investigate a fronthaul-limited cell-free massive multiple-input multiple-output (CF-mMIMO) system and propose a hybrid centralized-distributed precoding strategy that dynamical…
Performance Characterization of Continuous Reconfigurable Intelligent Surfaces
Amy S. Inwood, Peter J. Smith, Mahmoud AlaaEldin +1
We consider a reconfigurable intelligent surface (RIS) that can implement a phase rotation continuously over the whole surface rather than via a finite number of discrete elements.…
Energy Efficiency Optimization in Hardware-Constrained Large-Scale MIMO Systems
Xinlin Zhang, Michail Matthaiou, Mikael Coldrey +2
Large-scale multiple-input multiple-output (MIMO) communication systems can bring substantial improvement in spectral efficiency and/or energy efficiency, due to the excessive degr…
Secure Task Offloading and Resource Allocation Design for Multi-Layer Non-Terrestrial Networks
Alejandro Flores, Isabella W. G. da Silva, Vu Nguyen Ha +4
Remote and resource-constrained Internet-of-Things (IoT) deployments often lack terrestrial connectivity for task offloading, motivating non-terrestrial networks (NTNs) with onboar…
Static Power Consumption Modeling and Measurement of Reconfigurable Intelligent Surfaces
Jinghe Wang, Wankai Tang, Shi Jin +2
Reconfigurable intelligent surfaces (RISs) are anticipated to transform wireless communication in a way that is both economical and energy efficient. Revealing the practical power…
Smart Radio Environments
Gabriele Gradoni, Marco Di Renzo, Ana Diaz-Rubio +27
This Roadmap takes the reader on a journey through the research in electromagnetic wave propagation control via reconfigurable intelligent surfaces. Meta-surface modelling and desi…
SWIPT in Cell-Free Massive MIMO Using Stacked Intelligent Metasurfaces
Thien Duc Hua, Mohammadali Mohammadi, Hien Quoc Ngo +1
We investigate the integration of stacked intelligent metasurfaces (SIMs) into cell-free massive multiple input multiple output (CF-mMIMO) system to enhance the simultaneous wirele…
On the Impact of Spillover Losses in 28 GHz Rotman Lens Arrays for 5G Applications
Muhammad Ali Babar Abbasi, Harsh Tataria, Vincent F. Fusco +1
This work demonstrates the sensitivity of lens antenna arrays operating at millimeter-wave (mmWave) frequencies. Considering a Rotman lens array in receive mode, our investigation…
Massive Access in Extra Large-Scale MIMO with Mixed-ADC over Near Field Channels
Yikun Mei, Zhen Gao, De Mi +5
Massive connectivity for extra large-scale multi-input multi-output (XL-MIMO) systems is a challenging issue due to the near-field access channels and the prohibitive cost. In this…
Pinching-Antenna System-Assisted Localization: A Stochastic Geometry Perspective
Jiajun He, Xidong Mu, Hien Quoc Ngo +1
This paper proposes a novel localization framework underpinned by a pinching-antenna (PA) system, in which the target location is estimated using received signal strength (RSS) mea…
When Physical Layer Key Generation Meets RIS: Opportunities, Challenges, and Road Ahead
Ning Gao, Yu Han, Nannan Li +2
Physical layer key generation (PLKG) is a promising technology to obtain symmetric keys between a pair of wireless communication users in a plug-and-play manner. The shared entropy…
Cell-Free Massive MIMO Meets OTFS Modulation
Mohammadali Mohammadi, Hien Quoc Ngo, Michail Matthaiou
We provide the first-ever performance evaluation of orthogonal time frequency space (OTFS) modulation in cell-free massive multiple-input multiple-output (MIMO) systems. To investi…
Phase-Shift and Transmit Power Optimization for RIS-Aided Massive MIMO SWIPT IoT Networks
Mohammadali Mohammadi, Hien Quoc Ngo, Michail Matthaiou
We investigate reconfigurable intelligent surface (RIS)-assisted simultaneous wireless information and power transfer (SWIPT) Internet of Things (IoT) networks, where energy-limite…
On the Total Energy Efficiency of Cell-Free Massive MIMO
Hien Quoc Ngo, Le-Nam Tran, Trung Q. Duong +2
We consider the cell-free massive multiple-input multiple-output (MIMO) downlink, where a very large number of distributed multiple-antenna access points (APs) serve many single-an…
Power consumption Reduction in ELAA-Assisted ISAC Systems
Xiaomin Cao, Mohammadali Mohammadi, Hien Quoc Ngo +1
In this paper, we consider power consumption reduction in extremely large antenna arrays (ELAAs) for integrated sensing and communication (ISAC) applications. Although ELAAs are cr…
Optimal Per-Antenna ADC Bit Allocation in Correlated and Cell-Free Massive MIMO
Daniel Verenzuela, Emil Björnson, Michail Matthaiou
In Massive MIMO base stations (BSs), the hardware design needs to balance high spectral efficiency (SE) with low complexity. The level of hardware impairments (HWIs) indicates how…
Impact of Residual Transmit RF Impairments on Training-Based MIMO Systems
Xinlin Zhang, Michail Matthaiou, Mikael Coldrey +1
Radio-frequency (RF) impairments, which intimately exist in wireless communication systems, can severely limit the performance of multiple-input multiple-output (MIMO) systems. Alt…
Availability of Aerial Heterogeneous Networks for Reliable Emergency Communications
Teng Wu, Jiandong Li, Junyu Liu +4
We investigate network availability (NA) in aerial heterogeneous networks (AHetNets) for effective emergency rescue, where diverse delay-constrained communication services must be…
Electromagnetic Modeling of Holographic Intelligent Reflecting Surfaces at Terahertz Bands
Konstantinos Dovelos, Stylianos D. Assimonis, Hien Quoc Ngo +2
Intelligent reflecting surface (IRS)-assisted wireless communication is widely deemed a key technology for 6G systems. The main challenge in deploying an IRS-aided terahertz (THz)…
Multi-Domain Supervised Contrastive Learning for UAV Radio-Frequency Open-Set Recognition
Ning Gao, Tianrui Zeng, Bowen Chen +3
5G-Advanced (5G-A) has enabled the vibrant development of low altitude integrated sensing and communication (LA-ISAC) networks. As a core component of these networks, unmanned aeri…
Pinching-Antenna-Enabled Cognitive Radio Networks
Zeyang Sun, Xidong Mu, Shuai Han +2
This paper investigates a pinching-antenna (PA)-enabled cognitive radio network, where both the primary transmitter (PT) and secondary transmitter (ST) are equipped with a single w…
Super-Directive Antenna Arrays: How Many Elements Do We Need?
Ihsan Kanbaz, Okan Yurduseven, Michail Matthaiou
Super-directive antenna arrays have faced challenges in achieving high realized gains ever since their introduction in the academic literature. The primary challenges are high impe…
Topology-Aware Coordination for Multi-Functional Low-Altitude Wireless Networks
Jiajun He, Han Yu, Yiran Guo +6
Low-altitude wireless networks (LAWNs) are expected to consist of multi-tier, heterogeneous terrestrial and non-terrestrial devices, where effective coordination is essential to fu…
EsaNet: Environment Semantics Enabled Physical Layer Authentication
Ning Gao, Qiying Huang, Cen Li +2
Wireless networks are vulnerable to physical layer spoofing attacks due to the wireless broadcast nature, thus, integrating communications and security (ICAS) is urgently needed fo…
Pinching-Antenna-based Communications: Spectral Efficiency Analysis and Deployment Strategies
Mengyu Qian, Xidong Mu, Li You +1
A multiple-waveguide pinching-antenna (PA)-based multi-user communication system is investigated. With a given number of PAs, two deployment strategies are considered, namely the c…
Beamforming and Resource Allocation for Delay Minimization in RIS-Assisted OFDM Systems
Yu Ma, Xiao Li, Chongtao Guo +3
This paper investigates a joint beamforming and resource allocation problem in downlink reconfigurable intelligent surface (RIS)-assisted orthogonal frequency division multiplexing…
Mobile Communications in Intelligent Rail Transit: From LCX to PASS
Yiran Guo, Wei Chen, Cong Yu +3
Wireless communications in intelligent rail transit face harsh propagation conditions, including severe penetration loss, frequent blockages, and amplified large-scale fading. Exis…
How to Proactively Monitor Untrusted Communications with Cell-Free Massive MIMO?
Isabella W. G. da Silva, Zahra Mobini, Hien Q. Ngo +2
This paper studies a cell-free massive multiple-input multiple-output (CF-mMIMO) proactive monitoring system in which multiple multi-antenna monitoring nodes (MNs) are assigned to…
Cell-Free Massive MIMO with OTFS Modulation: Power Control and Resource Allocation
Mohammadali Mohammadi, Hien Quoc Ngo, Michail Matthaiou
We consider the downlink of cell-free massive multiple-input multiple-output (MIMO) systems with orthogonal time frequency space (OTFS) modulation. Two pilot-based channel estimati…
Prospective Multiple Antenna Technologies for Beyond 5G
Jiayi Zhang, Emil Björnson, Michail Matthaiou +3
Multiple antenna technologies have attracted large research interest for several decades and have gradually made their way into mainstream communication systems. Two main benefits…
Hybrid STAR-RIS Architecture for Joint Localization, Communication, and Power Transfer
Haoran Ni, Mohammadali Mohammadi, Xidong Mu +2
We propose a hybrid simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) architecture with dynamically switched active and passive elements to s…
BER Analysis and Optimization for Continuous RIS-Enabled NOMA
Mahmoud AlaaEldin, Amy S. Inwood, Peter J. Smith +1
This letter investigates a novel uplink (UL) system that integrates power-domain non-orthogonal multiple access (PD-NOMA) with a continuous reconfigurable intelligent surface (CRIS…
Multipair Two-way Half-Duplex Relaying with Massive Arrays and Imperfect CSI
Chuili Kong, Caijun Zhong, Michail Matthaiou +2
We consider a two-way half-duplex relaying system where multiple pairs of single antenna users exchange information assisted by a multi-antenna relay. Taking into account the pract…
RIS-Assisted Cell-Free Massive MIMO Relying on Reflection Pattern Modulation
Zeping Sui, Hien Quoc Ngo, Trinh Van Chien +2
We propose reflection pattern modulation-aided reconfigurable intelligent surface (RPM-RIS)-assisted cell-free massive multiple-input-multiple-output (CF-mMIMO) schemes for green u…
Deep Learning for CSI Feedback: One-Sided Model and Joint Multi-Module Learning Perspectives
Yiran Guo, Wei Chen, Feifei Sun +3
The use of deep learning (DL) for channel state information (CSI) feedback has garnered widespread attention across academia and industry. The mainstream DL architectures, e.g., Cs…
On the Multivariate Gamma-Gamma () Distribution with Arbitrary Correlation and Applications in Wireless Communications
Jiayi Zhang, Michail Matthaiou, George K. Karagiannidis +1
The statistical properties of the multivariate Gamma-Gamma () distribution with arbitrary correlation have remained unknown. In this paper, we provide analytical expressions…
Massive MIMO with Non-Ideal Arbitrary Arrays: Hardware Scaling Laws and Circuit-Aware Design
Emil Björnson, Michail Matthaiou, Mérouane Debbah
Massive multiple-input multiple-output (MIMO) systems are cellular networks where the base stations (BSs) are equipped with unconventionally many antennas, deployed on co-located o…
Hybrid OTFS/OFDM Design in Massive MIMO
Ruoxi Chong, Mohammadali Mohammadi, Hien Quoc Ngo +2
We consider a downlink (DL) massive multiple-input multiple-output (MIMO) system, where different users have different mobility profiles. To support this system, we categorize the…
Power Scaling of Uplink Massive MIMO Systems with Arbitrary-Rank Channel Means
Qi Zhang, Shi Jin, Kai-Kit Wong +2
This paper investigates the uplink achievable rates of massive multiple-input multiple-output (MIMO) antenna systems in Ricean fading channels, using maximal-ratio combining (MRC)…
Distributed Detection and Bandwidth Allocation with Hybrid Quantized and Full-Precision Observations over Multiplicative Fading Channels
Linlin Mao, Zeping Sui, Michail Matthaiou +1
A hybrid detector that fuses both quantized and full-precision observations is proposed for weak signal detection under additive and multiplicative Gaussian noise. We first derive…
How to Combine OTFS and OFDM Modulations in Massive MIMO?
Ruoxi Chong, Mohammadali Mohammadi, Hien Quoc Ngo +2
In this paper, we consider a downlink (DL) massive multiple-input multiple-output (MIMO) system, where different users have different mobility profiles. To support this system, we…
Multi-Way Massive MIMO with Maximum-Ratio Processing and Imperfect CSI
Chung Duc Ho, Hien Quoc Ngo, Michail Matthaiou +1
This paper considers a multi-way massive multiple-input multiple-output relaying system, where single-antenna users exchange their information-bearing signals with the help of one…
Secure Transmission in Cell-Free Massive MIMO under Active Eavesdropping
Yasseen Sadoon Atiya, Zahra Mobini, Hien Quoc Ngo +1
We study secure communications in cell-free massive multiple-input multiple-output (CF-mMIMO) systems with multi-antenna access points (APs) and protective partial zero-forcing (PP…
Power-Efficient XL-MIMO Design for Mixed Near- and Far-Field SWIPT Systems
Muhammad Zeeshan Mumtaz, Mohammadali Mohammadi, Hien Quoc Ngo +2
The paper proposes a power‑efficient design for extra‑large MIMO systems that serve simultaneous wireless information and power transfer (SWIPT) users in both near‑field and far‑fi…
Cell-Free Massive MIMO-Assisted SWIPT for IoT Networks
Mohammadali Mohammadi, Le-Nam Tran, Zahra Mobini +2
This paper studies cell-free massive multiple-input multiple-output (CF-mMIMO) systems that underpin simultaneous wireless information and power transfer (SWIPT) for separate infor…
Spatial Limits of Fluid Antenna Systems
Amy S. Inwood, Peter J. Smith, Rajitha Senanayake +1
Continuous fluid antenna systems (CFASs) represent an upper bound on the spatial diversity performance of fluid antenna systems (FASs), achieved when antennas may be positioned any…
Pilot Power Allocation Through User Grouping in Multi-Cell Massive MIMO Systems
Pei Liu, Shi Jin, Tao Jiang +2
In this paper, we propose a relative channel estimation error (RCEE) metric, and derive closed-form expressions for its expectation and the achievable uplink rat…
Integrated Communications and Security: RIS-Assisted Simultaneous Transmission and Generation of Secret Keys
Ning Gao, Yuze Yao, Shi Jin +2
We develop a new integrated communications and security (ICAS) design paradigm by leveraging the concept of reconfigurable intelligent surfaces (RISs). In particular, we propose RI…
A Multi-Scenario UAV RF Dataset with Real-World Acquisition and Signal Processing Benchmarking
Haolin Zheng, Ning Gao, Zhenghang Zhu +3
We present a real-world multi-scenario unmanned aerial vehicle (UAV) radio frequency (RF) dataset, namely DRFF-R2, which is collected using a dedicated acquisition platform under d…
On the Spectral Efficiency of Space-Constrained Massive MIMO with Linear Receivers
Jiayi Zhang, Linglong Dai, Michail Matthaiou +2
In this paper, we investigate the spectral efficiency (SE) of massive multiple-input multiple-output (MIMO) systems with a large number of antennas at the base station (BS) account…
Near-Field SWIPT Using XL-MIMO: Power Allocation and Subarray Activation
Muhammad Zeeshan Mumtaz, Mohammadali Mohammadi, Hien Quoc Ngo +1
This paper investigates the simultaneous wireless information and power transfer (SWIPT) capability of a modular extremely large multiple-input multiple-output (XL-MIMO) system, in…
On the MIMO Capacity with Residual Transceiver Hardware Impairments
Xinlin Zhang, Michail Matthaiou, Emil Björnson +2
Radio-frequency (RF) impairments in the transceiver hardware of communication systems (e.g., phase noise (PN), high power amplifier (HPA) nonlinearities, or in-phase/quadrature-pha…
DYVERSE: DYnamic VERtical Scaling in Multi-tenant Edge Environments
Nan Wang, Michail Matthaiou, Dimitrios S. Nikolopoulos +1
Multi-tenancy in resource-constrained environments is a key challenge in Edge computing. In this paper, we develop 'DYVERSE: DYnamic VERtical Scaling in Edge' environments, which i…