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Related papers: Joint Active and Passive Beamforming for RIS-aided…

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The amalgamation of cell-free networks and reconfigurable intelligent surface (RIS) has become a prospective technique for future sixth-generation wireless communication systems. In this paper, we focus on the precoding and beamforming…

Information Theory · Computer Science 2023-11-23 Peng Zhang , Jiayi Zhang , Huahua Xiao , Xiaodan Zhang , Derrick Wing Kwan Ng , Bo Ai

In this paper, we consider and study a cell-free massive MIMO (CF-mMIMO) system aided with reconfigurable intelligent surfaces (RISs), where a large number of access points (APs) cooperate to serve a smaller number of users with the help of…

Information Theory · Computer Science 2021-05-17 Bayan Al-Nahhas , Mohanad Obeed , Anas Chaaban , Md. Jahangir Hossain

By reconfiguring the propagation environment of electromagnetic waves artificially, reconfigurable intelligent surfaces (RISs) have been regarded as a promising and revolutionary hardware technology to improve the energy and spectrum…

Signal Processing · Electrical Eng. & Systems 2020-06-03 Huiyuan Yang , Xiaojun Yuan , Jun Fang , Ying-Chang Liang

As communication systems that employ millimeter wave (mmWave) frequency bands must use large antenna arrays to overcome the severe propagation loss of mmWave signals, hybrid beamforming has been considered as an integral component of mmWave…

Signal Processing · Electrical Eng. & Systems 2022-06-28 Sung Hyuck Hong , Jaeyong Park , Sung-Jin Kim , Junil Choi

Reconfigurable intelligent surface (RIS)-assisted cell-free (CF) multiple-input multiple-output (MIMO) networks can significantly enhance system performance. However, the extensive deployment of RIS elements imposes considerable channel…

Signal Processing · Electrical Eng. & Systems 2025-06-30 Hongqin Ke , Jindan Xu , Wei Xu , Chau Yuen , Zhaohua Lu

Reconfigurable intelligent surface (RIS)-based communication networks promise to improve channel capacity and energy efficiency. However, the promised capacity gains could be negligible for passive RISs because of the double pathloss…

Information Theory · Computer Science 2022-06-30 Shayan Zargari , Azar Hakimi , Chintha Tellambura , Sanjeewa Herath

Recently, the reconfigurable intelligent surface (RIS), benefited from the breakthrough on the fabrication of programmable meta-material, has been speculated as one of the key enabling technologies for the future six generation (6G)…

Information Theory · Computer Science 2022-06-23 Chongwen Huang , Ronghong Mo , Chau Yuen

Reconfigurable intelligent surfaces (RISs) have emerged as a candidate technology for future 6G networks. However, due to the "multiplicative fading" effect, the existing passive RISs only achieve a negligible capacity gain in environments…

Information Theory · Computer Science 2023-01-20 Zijian Zhang , Linglong Dai , Xibi Chen , Changhao Liu , Fan Yang , Robert Schober , H. Vincent Poor

Reconfigurable intelligent surfaces (RISs) have a revolutionary capability to customize the radio propagation environment for wireless networks. To fully exploit the advantages of RISs in wireless systems, the phases of the reflecting…

Machine Learning · Computer Science 2022-04-29 Zongze Li , Shuai Wang , Qingfeng Lin , Yang Li , Miaowen Wen , Yik-Chung Wu , H. Vincent Poor

The adoption of a Reconfigurable Intelligent Surface (RIS) for downlink multi-user communication from a multi-antenna base station is investigated in this paper. We develop energy-efficient designs for both the transmit power allocation and…

Information Theory · Computer Science 2022-06-23 Chongwen Huang , Alessio Zappone , George C. Alexandropoulos , Mérouane Debbah , Chau Yuen

Reconfigurable intelligent surfaces (RIS) have been actively researched as a potential technique for future wireless communications, which intelligently ameliorate the signal propagation environment. In the conventional design, each RIS…

Information Theory · Computer Science 2022-03-17 Qingchao Li , Mohammed El-Hajjar , Ibrahim Hemadeh , Arman Shojaeifard , Alain A. M. Mourad , Bruno Clerckx , Lajos Hanzo

Reconfigurable intelligent surface (RIS) is a promising technology for future wireless communications due to its capability of optimizing the propagation environments. Nevertheless, in literature, there are few prototypes serving multiple…

Signal Processing · Electrical Eng. & Systems 2024-05-14 Zhibo Zhou , Haifan Yin , Li Tan , Ruikun Zhang , Kai Wang , Yingzhuang Liu

This study investigates a robust reconfigurable intelligent surface (RIS)-assisted multiple-input multiple-output (MIMO) system for secure wireless communication, in which a multi-antenna transmitter (Alice) sends confidential messages to a…

Signal Processing · Electrical Eng. & Systems 2026-02-20 Rakesh Ranjan , Ahmad Sirojuddin , Manjesh K. Hanawal , Himanshu B. Mishra , Wan-Jen Huang ID

Reconfigurable intelligent surface~(RIS) has drawn a great attention worldwide as it can create favorable propagation conditions by controlling the phase shifts of the reflected signals at the surface to enhance the communication quality.…

Information Theory · Computer Science 2020-01-24 Hongliang Zhang , Boya Di , Lingyang Song , Zhu Han

Reconfigurable intelligent surface (RIS) is a promising technology to enhance the spectral and energy efficiency in a wireless communication system. The design of the phase shifts of an RIS in every channel coherence interval demands a huge…

Signal Processing · Electrical Eng. & Systems 2024-05-15 Sadaf Syed , Dominik Semmler , Donia Ben Amor , Michael Joham , Wolfgang Utschick

This paper investigates the optimization of reconfigurable intelligent surface (RIS) in an integrated sensing and communication (ISAC) system. \red{To meet the demand of growing number of devices, power domain non-orthogonal multiple access…

Signal Processing · Electrical Eng. & Systems 2023-09-13 Wanting Lyu , Yue Xiu , Xinyang Li , Songjie Yang , Phee Lep Yeoh , Yonghui Li , Zhongpei Zhang

In recent years there has been a growing interest in reconfigurable intelligent surfaces (RISs) as enablers for the realization of smart radio propagation environments which can provide performance improvements with low energy consumption…

Information Theory · Computer Science 2022-07-26 Nuno Souto , João Carlos Silva

Transmitting data using the phases on reconfigurable intelligent surfaces (RIS) is a promising solution for future energy-efficient communication systems. Recent work showed that a virtual phased massive multiuser…

Signal Processing · Electrical Eng. & Systems 2023-10-26 Wai-Yiu Keung , Hei Victor Cheng , Wing-Kin Ma

This paper considers wireless communication assisted by a reconfigurable intelligent surface (RIS), focusing on the two-timescale approach, in which the RIS phase shifts are optimized based on channel statistics to mitigate the overheads…

Information Theory · Computer Science 2025-07-30 Masoud Sadeghian , Angel Lozano , Gabor Fodor

In this paper, we investigate the potential of employing reconfigurable intelligent surface (RIS) in integrated sensing and communication (ISAC) systems. In particular, we consider an RIS-assisted ISAC system in which a multi-antenna base…

Signal Processing · Electrical Eng. & Systems 2023-01-27 Rang Liu , Ming Li , A. Lee Swindlehurst