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Related papers: Unsupervised Learning for Passive Beamforming

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This paper studies the beamforming optimization challenge in reconfigurable intelligent surface (RIS)-aided multiple-input single-output (MISO) systems, where the RIS phase configuration is discrete. Conventional optimization methods for…

Signal Processing · Electrical Eng. & Systems 2024-01-17 Rujing Xiong , Xuihui Dong , Tiebin Mi , Kai Wan , Robert Caiming Qiu

Reconfigurable intelligent surfaces (RISs) have become a promising technology to meet the requirements of energy efficiency and scalability in future six-generation (6G) communications. However, a significant challenge in RISs-aided…

Information Theory · Computer Science 2024-08-22 Xinquan Wang , Fenghao Zhu , Qianyun Zhou , Qihao Yu , Chongwen Huang , Ahmed Alhammadi , Zhaoyang Zhang , Chau Yuen , Mérouane Debbah

Since reconfigurable intelligent surface (RIS) is considered to be a passive reflector for rate performance enhancement, a RIS-aided amplify-and-forward (AF) relay network is presented. By jointly optimizing the beamforming matrix at AF…

Information Theory · Computer Science 2023-03-01 Xuehui Wang , Feng Shu , Riqing Chen , Peng Zhang , Qi Zhang , Guiyang Xia , Weiping shi , Jiangzhou Wang

Active Reconfigurable Intelligent Surfaces (RIS) are a promising technology for 6G wireless networks. This paper investigates a novel hybrid deep reinforcement learning (DRL) framework for resource allocation in a multi-user uplink system…

Signal Processing · Electrical Eng. & Systems 2025-12-29 Mohamed Shalma , Engy Aly Maher , Ahmed El-Mahdy

The integration of Reconfigurable Intelligent Surfaces (RISs) into wireless environments endows channels with programmability, and is expected to play a key role in future communication standards. To date, most RIS-related efforts focus on…

Information Theory · Computer Science 2022-02-17 Kyriakos Stylianopoulos , Nir Shlezinger , Philipp del Hougne , George C. Alexandropoulos

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

The Reconfigurable Intelligent Surface (RIS) constitutes one of the prominent technologies for the next generation of wireless communications. It is envisioned to enhance the signal coverage in cases when the direct link of the…

Signal Processing · Electrical Eng. & Systems 2022-11-01 Kun Chen-Hu , George C. Alexandropoulos , Ana García Armada

In next-generation wireless networks, reconfigurable intelligent surface (RIS)-assisted multiple-input multiple-output (MIMO) systems are foreseeable to support a large number of antennas at the transceiver as well as a large number of…

Information Theory · Computer Science 2023-01-24 Chang Cai , Xiaojun Yuan , Ying-Jun Angela Zhang

The emerging technology of Reconfigurable Intelligent Surfaces (RISs) is provisioned as an enabler of smart wireless environments, offering a highly scalable, low-cost, hardware-efficient, and almost energy-neutral solution for dynamic…

Information Theory · Computer Science 2022-05-11 George C. Alexandropoulos , Kyriakos Stylianopoulos , Chongwen Huang , Chau Yuen , Mehdi Bennis , Mérouane Debbah

The physical layer security (PLS) is investigated for reconfigurable intelligent surface (RIS) assisted wireless networks, where a source transmits its confidential information to a legitimate destination with the aid of a single small RIS…

Information Theory · Computer Science 2022-10-06 Haiyan Guo , Zhen Yang , Yulong Zou , Bin Lyu , Yuhan Jiang , Lajos Hanzo

Reconfigurable intelligent surfaces (RISs) achieve high passive beamforming gains for signal enhancement or interference nulling by dynamically adjusting their reflection coefficients. Their employment is particularly appealing for…

Information Theory · Computer Science 2022-12-01 Ming-Min Zhao , Kaidi Xu , Yunlong Cai , Yong Niu , Lajos Hanzo

In this letter, we consider an intelligent reflecting surface (IRS)-assisted multiuser communication system, where an IRS is deployed to provide virtual line-of-sight (LoS) links between an access point (AP) and multiple users. We consider…

Information Theory · Computer Science 2020-06-30 Changsheng You , Beixiong Zheng , Rui Zhang

Large intelligent surface (LIS) has emerged as a promising new solution to improve the energy and spectrum efficiency of wireless networks. A LIS, composed of a large number of low-cost and energy-efficient reconfigurable passive reflecting…

Information Theory · Computer Science 2019-08-09 Wenjing Yan , Xiaoyan Kuai , Xiaojun Yuan

Most research works on reconfigurable intelligent surfaces (RIS) rely on idealized models of the reflection coefficients, i.e., uniform reflection amplitude for any phase and sufficient phase shifting capability. In practice however, such…

Signal Processing · Electrical Eng. & Systems 2024-04-17 Lin Cao , Haifan Yin , Li Tan , Xilong Pei

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

We introduce a novel deep reinforcement learning (DRL) approach to jointly optimize transmit beamforming and reconfigurable intelligent surface (RIS) phase shifts in a multiuser multiple input single output (MU-MISO) system to maximize the…

Networking and Internet Architecture · Computer Science 2023-03-30 Baturay Saglam , Doga Gurgunoglu , Suleyman S. Kozat

The integration of tunability mechanisms in the metasurface design has unleashed a tremendous potential for wireless communications. In particular, reconfigurable intelligent surfaces (RISs) can manipulate the reflections of an incident…

Applied Physics · Physics 2025-04-10 Vasileios G. Ataloglou , George V. Eleftheriades

This paper considers an active reconfigurable intelligent surface (RIS)-aided integrated sensing and communication (ISAC) system. We aim to maximize radar signal-to-interference-plus-noise-ratio (SINR) by jointly optimizing the beamforming…

Information Theory · Computer Science 2024-02-06 Zhiyuan Yu , Hong Ren , Cunhua Pan , Gui Zhou , Boshi Wang , Mianxiong Dong , Jiangzhou Wang

This paper focuses on multi-user downlink signal transmission in a wireless system aided by multiple reconfigurable intelligent surfaces (RISs). In such a multi-RIS, multi-user, multi-antenna scenario, determining a set of RIS phase shifts…

Information Theory · Computer Science 2023-03-17 Wei Jiang , Hans D. Schotten

In this paper, intelligent reflecting surface (IRS) is introduced to enhance the network performance of cognitive radio (CR) systems. Specifically, we investigate robust beamforming design based on both bounded channel state information…

Signal Processing · Electrical Eng. & Systems 2024-01-08 Lei Zhang , Cunhua Pan , Yu Wang , Hong Ren , Kezhi Wang
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