Article
Computer Science, Information Systems
Yunyang Zhang, Aijun Liu, Pinghui Li, Siqi Jiang
Summary: This article proposes the use of deep neural networks to solve challenges in LEO satellite communication systems and introduces the SatCP and SatHB schemes for downlink CSI acquisition and hybrid beamforming design. Numerical results demonstrate the effectiveness of these schemes in improving system capacity and achieving global high-speed interconnection.
IEEE INTERNET OF THINGS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Zhangjie Peng, Xianzhe Chen, Wei Xu, Cunhua Pan, Li-Chun Wang, Lajos Hanzo
Summary: This study investigates massive access in IoT using MIMO technology and AF relay systems, with the use of the AMP algorithm for device activity detection and channel estimation. Achievable rates for active devices are analyzed and closed-form expressions derived for different beamforming schemes at the relay. A low-complexity algorithm is proposed to optimize the pilot length, with simulation results verifying the accuracy of the proposed strategies.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2021)
Article
Telecommunications
Mobeen Mahmood, Asil Koc, Tho Le-Ngoc
Summary: This letter investigates the performance of various three-dimensional array structures in the design of hybrid precoder for millimeter wave multi-user massive MIMO systems. The results show that 3D array structures can provide high spectral and energy efficiencies, with non-varying achievable rate independent from the user angular location.
IEEE COMMUNICATIONS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Emily Naviasky, Lorenzo Iotti, Greg LaCaille, Borivoje Nikolic, Elad Alon, Ali M. Niknejad
Summary: This article introduces a 71-86 GHz 16-element array receiver ASIC designed for Massive MIMO wireless uplink, with support for up to 16 spatially multiplexed users simultaneously. The ASIC is optimized for low power consumption, achieving high data rates and multiple user connections.
IEEE JOURNAL OF SOLID-STATE CIRCUITS
(2021)
Article
Engineering, Electrical & Electronic
Rafael P. Torres, Jesus R. Perez, Luis Valle
Summary: In this letter, a comparative analysis is presented on the hardening effect of concentrated and distributed massive multiple-input-multiple-output channels (C-mMIMO and D-mMIMO, respectively). The analysis is conducted in two buildings with similar structural characteristics, considering the frequency bands of 3.5 and 26 GHz for 5G deployments. Experimental data at 3.5 GHz and simulation results at 26 GHz using a rigorous ray tracing method are used. Both measurements and simulations show that indoor environments provide a sufficiently high level of hardening for mMIMO systems, contributing to the reliability of communication systems or sensor networks.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2023)
Article
Telecommunications
Azzam Al-Nahari, Riku Jantti, Deepak Mishra, Jyri Hamalainen
Summary: This study investigates the role of massive MIMO in improving the spectral and energy efficiency of monostatic backscatter communication systems, as well as the performance of precoders and combiners. The results show that with perfect channel state information, the total transmit power can be scaled down by a factor of the square of the number of transmit antennas without loss in performance.
IEEE COMMUNICATIONS LETTERS
(2021)
Article
Chemistry, Analytical
Yushintia Pramitarini, Ridho Hendra Yoga Perdana, Kyusung Shim, Beongku An
Summary: This paper proposes a deep learning-based secure multicast routing protocol for flying ad hoc networks. The protocol predicts secure and unsecured routes using deep learning to avoid wormhole attacks and improves node connectivity and multicast member management with a particle swarm optimization-based clustering protocol.
Article
Engineering, Electrical & Electronic
Qiang Sun, Xiaodi Ji, Zhe Wang, Xiaomin Chen, Yongjie Yang, Jiayi Zhang, Kai-Kit Wong
Summary: This paper studies the impact of hardware impairments on cell-free mMIMO systems in practical applications. The results show that the effect of hardware impairments can be mitigated in the presence of user terminals with multiple antennas. However, the achievable transmission rate is constrained by pilot contamination and pilot overhead.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Xin Liu, Wenhua Chen, Jiaming Chu, Fadhel M. Ghannouchi, Zhenghe Feng
Summary: A novel multi-stream spatial digital predistortion technique is proposed in this paper to address the DPD implementation issue in fully-connected hybrid beamforming transmitters by linearizing beam signals instead of individual PAs. The proposed technique achieved improvements of better than 13 dB adjacent channel power ratio and 12 dB normalized mean square error in experimental tests.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2021)
Article
Engineering, Electrical & Electronic
Hanlin Xiu, Zhen Gao, Anwen Liao, Yikun Mei, Dezhi Zheng, Shufeng Tan, Marco Di Renzo, Lajos Hanzo
Summary: This paper investigates a joint active user detection (AUD) and channel estimation (CE) scheme based on compressive sensing (CS) for millimeter-wave (mmWave)/terahertz (THz) systems in the context of non-uniform array structures. By exploiting the structured sparsity of mmWave/THz massive IoT access channels, the authors formulate the problem as a multiple measurement vector (MMV)-CS problem and develop an orthogonal approximate message passing (OAMP)-EM-MMV algorithm to solve it. Simulation results show the improved performance of the proposed scheme compared to conventional CS-based algorithms.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
K. E. Purushothaman, V. Nagarajan
Summary: 5G network is crucial in various fields and user numbers are increasing. Machine learning methods are introduced for better resource allocation in 5G networks. The proposed method using deep neural network for resource allocation in 5G mMIMO outperforms existing methods.
INTERNATIONAL JOURNAL OF ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Jinlong Zhan, Xiaodai Dong
Summary: In this paper, a framework for interference cancellation in downlink millimeter wave multi-user massive MIMO systems using hybrid beamforming is proposed. Three successive interference cancellation aided hybrid beamforming algorithms are introduced to address inter-user and intra-user interference. The numerical results show that these algorithms outperform existing approaches in terms of spectral efficiency.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Jiajia Guo, Chao-Kai Wen, Shi Jin
Summary: The proposed CsiFBnet framework focuses on maximizing beamforming performance gain rather than feedback accuracy, and is applied to single-cell and multi-cell systems. Using an autoencoder architecture, the neural networks are trained with an unsupervised learning strategy, showing significant performance improvement and complexity reduction compared to conventional DL-based CSI feedback methods in simulation results.
IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
(2021)
Article
Computer Science, Information Systems
Jiayi Zhang, Jingyi Fan, Jing Zhang, Derrick Wing Kwan Ng, Qiang Sun, Bo Ai
Summary: This article investigates the performance of NOMA-based cell-free mMIMO for IoT considering spatially correlated Rician fading channels. The closed form expressions for SE and energy efficiency are derived, considering imperfect successive interference cancellation and pilot contamination. The results show that the magnitude of spatial correlation negligibly affects the SE in spatially correlated Rician fading channels, and NOMA-based cell-free mMIMO provides significant performance gain compared to conventional orthogonal multiple-access schemes.
IEEE INTERNET OF THINGS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Mohammed Almoneer, Jin Gyu Lim, Hang Yu, Patrick Mitran, Slim Boumaiza
Summary: This article investigates the impact of precoding on the performance of massive MIMO transmitters with antenna crosstalk. A new metric, average active impedance, is introduced to quantify load modulation, and three new precoding schemes are proposed to improve the transmitter's resilience to variation in channel conditions. Experiments confirmed that the proposed schemes equalize average-power levels across all RF chains.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2022)
Article
Engineering, Electrical & Electronic
Xiaochen Xia, Yurong Wang, Kui Xu, Youyun Xu
Summary: This paper proposes a novel binary channel feature map (CFM) concept to address the challenge of unknown propagation environment in aerial platform (AP)-assisted air-to-ground (A2G) communications. With the assistance of binary CFM, a unified framework for A2G information and energy delivery is proposed, achieving optimization of transmit parameters, AP position, and efficient delivery of information and energy.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2022)
Article
Computer Science, Information Systems
Tao Zhou, Kui Xu, Zhexian Shen, Wei Xie, Dongmei Zhang, Jianhui Xu
Summary: This letter studies a new application scenario for intelligent reflecting surfaces (IRSs) - using IRSs for user positioning. Multiple aerial intelligent reflecting surfaces (AIRSs) are deployed in the air to locate users in a certain area. Experimental results show that the proposed positioning strategy has good performance.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Jiahua Qiu, Kui Xu, Xiaochen Xia, Zhexian Shen, Wei Xie, Dongmei Zhang, Meng Wang
Summary: This paper studies how to improve the secure transmission performance of cell-free massive MIMO systems by using location technology. It proposes a user location estimation method based on fingerprint positioning and a channel estimation algorithm based on location information. The results show that the proposed secure transmission strategy can effectively increase the secrecy rate in strong interference environments.
IEEE TRANSACTIONS ON SIGNAL AND INFORMATION PROCESSING OVER NETWORKS
(2022)
Article
Telecommunications
Chengjian Liao, Kui Xu, Hongpeng Zhu, Xiaochen Xia, Qiao Su, Nan Sha
Summary: In order to address the physical layer security issues in the information backhaul link of the satellite-UAV integrated network, a two-layer Stackelberg game model is proposed. This model can resist eavesdropping and jamming attacks by adjusting the transmission power strategy and sending jamming signals. A price incentive mechanism is established to encourage active participation and cooperation of UAVs.
CHINA COMMUNICATIONS
(2022)
Article
Computer Science, Information Systems
Huazhi Hu, Wei Xie, Kui Xu, Xiaochen Xia, Meng Wang, Shengwei Liu, Na Li
Summary: This paper presents the application of intelligent reflecting surfaces (IRSs) in a cell-free massive MIMO network to enhance secure transmission. By jointly optimizing active beamforming of access points (APs) and passive beamforming of IRSs, the leaked information to eavesdroppers is limited and the system's downlink transmission is maximized. The proposed joint precoding framework solves the nonconvex problem through multidimensional complex quadratic transformation and convex optimization methods, and obtains the optimal solution using an alternating algorithm.
SECURITY AND COMMUNICATION NETWORKS
(2022)
Article
Engineering, Electrical & Electronic
Chen Wei, Kui Xu, Zhexian Shen, Xiaochen Xia, Wei Xie, Chunguo Li
Summary: This paper investigates the uplink transmission for user-centric cell-free massive MIMO systems. A novel pilot assignment scheme is proposed to alleviate pilot contamination, and a location-aided combining scheme is introduced to balance the relationship among spectral efficiency, user equipment fairness and complexity. Furthermore, a fairness coefficient and a metric representing inter-user interference are proposed to evaluate system performance.
EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING
(2022)
Article
Telecommunications
Nan Ma, Kui Xu, Xiaochen Xia, Chen Wei, Qiao Su, Maiying Shen, Wei Xie
Summary: This paper proposes an anti-jamming power control framework that improves the sum rate and energy efficiency of UAV-assisted air-to-ground communication. It also tracks user locations through a trajectory design scheme.
IEEE COMMUNICATIONS LETTERS
(2022)
Article
Telecommunications
Chen Wei, Kui Xu, Xiaochen Xia, Qiao Su, Maiying Shen, Wei Xie, Chunguo Li
Summary: In this paper, we investigate the problem of user-centric access point (AP) selection for cell-free massive MIMO systems. We employ game theory to model the AP service cluster formation as a local altruistic game and propose an improved concurrent spatial adaptive play algorithm to achieve the optimal solution. Simulation results show that the proposed algorithm outperforms existing algorithms in terms of convergence speed, highlighting the superiority of the game-theoretic AP selection method.
IEEE COMMUNICATIONS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Guojie Hu, Zan Li, Jiangbo Si, Kui Xu, Donghui Xu, Yunlong Cai, Naofal Al-Dhahir
Summary: This paper investigates UAV-enabled proactive eavesdropping over distributed transmit beamforming-based suspicious communications. The approximated distributions of the receiving SINR at D and the UAV are characterized in closed form using the Laguerre series approximation and the central limit theorem. A novel and low-complexity solution is proposed in the high SNR regime to maximize the minimum eavesdropping success probability of the UAV for those suspicious communications links.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
Mi Zhang, Xiaochen Xia, Kui Xu, Xiaoqin Yang, Wei Xie, Yunkun Li, Yang Liu
Summary: This paper investigates orthogonal time-frequency space (OTFS) modulation as a promising waveform for achieving integrated sensing and communication (ISAC) due to its advantages in high-mobility adaptability and spectral efficiency. Accurate channel acquisition is critical in OTFS modulation-based ISAC systems for both communication reception and sensing parameter estimation. However, the fractional Doppler frequency shift significantly spreads the effective channels of the OTFS signal, making efficient channel acquisition challenging. To address this issue, a new structured Bayesian learning approach is proposed in this paper, which includes a novel structured prior model for the delay-Doppler channel and a successive majorization-minimization (SMM) algorithm for efficient posterior channel estimate computation. Simulation results show that the proposed approach outperforms the reference schemes, especially in the low signal-to-noise ratio (SNR) region.
Article
Computer Science, Information Systems
Na Li, Yuanyuan Gao, Kui Xu, Mingxi Guo, Nan Sha, Xiaoyu Wang, Guangyu Wang
Summary: This article investigates the security performance of a CF massive MIMO system composed of randomly distributed APs and multiple users. A spatial sparsity-based pilot attack detection method is proposed to determine the presence of an eavesdropper, and different data transmission schemes are developed accordingly. In the presence of an eavesdropper, a rate maximization power allocation algorithm is proposed, while an achievable rate equalization power allocation algorithm is proposed in the absence of an eavesdropper, providing fair services for all legitimate users. Furthermore, an AP selection scheme and conjugate beamforming are used to enhance the system's security performance and mitigate the impact of a pilot spoofing attack.
IEEE SYSTEMS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Guojie Hu, Zan Li, Jiangbo Si, Kui Xu, Yunlong Cai, Donghui Xu, Naofal Al-Dhahir
Summary: In this paper, we propose a novel simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS)-assisted proactive eavesdropping strategy to address the trade-off between concealment and eavesdropping performance in wireless surveillance. By deploying a STAR-RIS between the monitor and the suspicious system, reflection and transmission are implemented to vary the channel power gains, thereby facilitating eavesdropping.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Kui Xu, Xiaochen Xia, Chunguo Li, Wei Xie, Jie Liu, Rangang Zhu, Huasen He
Summary: This paper proposes a robust DOA estimation and tracking scheme for massive MIMO-OFDM systems using integrated sensing and communication. Simulation results demonstrate that the proposed method can accurately estimate DOA even in low signal-to-noise ratio conditions.
SCIENCE CHINA-INFORMATION SCIENCES
(2023)
Article
Computer Science, Information Systems
Xiaochen Xia, Kui Xu, Wei Xie, Youyun Xu, Nan Sha, Yurong Wang
Summary: This article introduces a method using aerial base stations to solve coverage, deployment and cost issues in wireless networks. By constructing a binary radio map, a framework for multiple base station deployment and user association is proposed and tested in a complex urban scenario, showing improved performance compared to reference schemes.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Kui Xu, Mouhua Huang, Dongmei Zhang, Xiaochen Xia, Wei Xie, Nan Sha
Summary: Cell-free massive MIMO networks provide high spectral efficiency and uniform signal coverage for smart city applications, but the limited capacity of the fronthaul link constrains the optimization of user rate. This paper proposes QT-MM and QT-SM optimization algorithms for CF mMIMO OFDM systems, which effectively prevent very low user rates when the fronthaul capacity is limited.
IEEE OPEN JOURNAL OF THE COMMUNICATIONS SOCIETY
(2022)
