English
Related papers

Related papers: Channel Estimation for RIS-Empowered Multi-User MI…

200 papers

Reconfigurable intelligent surface (RIS) is a candidate technology for future wireless networks. It enables to shape the wireless environment to reach massive connectivity and enhanced data rate. The promising gains of RIS-assisted networks…

Signal Processing · Electrical Eng. & Systems 2022-06-09 Paulo R. B. Gomes , Gilderlan T. de Araújo , Bruno Sokal , André L. F. de Almeida , Behrooz Makki , Gábor Fodor

Double-reconfigurable intelligent surface (RIS) is a promising technique, achieving a substantial gain improvement compared to single-RIS techniques. However, in double-RIS-aided systems, accurate channel estimation is more challenging than…

Information Theory · Computer Science 2022-11-30 Songjie Yang , Wanting Lyu , Yue Xiu , Zhongpei Zhang , Chau Yuen

This paper proposes a correlation-based three-stage channel estimation strategy with low pilot overhead for reconfigurable intelligent surface (RIS)-aided millimeter wave (mmWave) multi-user (MU) MIMO systems, in which both users and base…

Signal Processing · Electrical Eng. & Systems 2025-02-11 Liuchang Zhuo , Cunhua Pan , Hong Ren , Ruisong Weng , Shi Jin , A. Lee Swindlehurst , Jiangzhou Wang

This paper investigates the reconfigurable reflecting surface (RIS)-aided multiple-input-single-output (MISO) systems with imperfect channel state information (CSI), where RIS-related channels are modeled by Rician fading. Considering the…

Information Theory · Computer Science 2021-07-13 Kangda Zhi , Cunhua Pan , Hong Ren , Kezhi Wang , Maged Elkashlan

Beyond diagonal reconfigurable intelligent surface (BD-RIS) refers to a family of RIS architectures characterized by scattering matrices not limited to being diagonal and enables higher wave manipulation flexibility and large performance…

Signal Processing · Electrical Eng. & Systems 2025-04-16 Rui Wang , Shuowen Zhang , Bruno Clerckx , Liang Liu

Reconfigurable Intelligent Surface (RIS) technology has emerged as a key enabler for future wireless communications. However, its potential is constrained by the difficulty of acquiring accurate user-to-RIS channel state information (CSI),…

Signal Processing · Electrical Eng. & Systems 2026-04-20 Md. Shahriar Sadid , Ali A. Nasir , Saad Al-Ahmadi , Samir Al-Ghadhban

Recent research has focused on reconfigurable intelligent surface (RIS)-assisted cell-free systems with the goal of enhancing coverage and lowering the cost of cell-free networks. However, current research makes the assumption that the…

Signal Processing · Electrical Eng. & Systems 2022-07-29 Songjie Yang , Chenfei Xie , Mingwei Wang , Zhongpei Zhang

In this paper, we propose a novel two-stage based uplink channel estimation strategy with reduced pilot overhead and error propagation for a reconfigurable intelligent surface (RIS)-aided multi-user (MU) millimeter wave (mmWave) system.…

Signal Processing · Electrical Eng. & Systems 2022-08-24 Zhendong Peng , Cunhua Pan , Gui Zhou , Hong Ren

The reconfigurable intelligent surface (RIS) with low hardware cost and energy consumption has been recognized as a potential technique for future 6G communications to enhance coverage and capacity. To achieve this goal, accurate channel…

Information Theory · Computer Science 2021-01-26 Xiuhong Wei , Decai Shen , Linglong Dai

The deployment of multiple reconfigurable intelligent surfaces (RISs) enhances the propagation environment by improving channel quality, but it also complicates channel estimation. Following the conventional wireless communication system…

Information Theory · Computer Science 2024-11-22 Weicong Chen , Yu Han , Chao-Kai Wen , Xiao Li , Shi Jin

This paper proposes a three-stage uplink channel estimation protocol for reconfigurable intelligent surface (RIS)-aided multi-user (MU) millimeter-wave (mmWave) multiple-input single-output (MISO) systems, where both the base station (BS)…

Signal Processing · Electrical Eng. & Systems 2026-02-24 Tian Qiu , Ruidong Li , Cunhua Pan , Taihaon Zhang , Dongnan Xia , Changhong Wang , Hong Ren

The reconfigurable intelligent surface (RIS) technology is a promising enabler for millimeter wave (mmWave) wireless communications, as it can potentially provide spectral efficiency comparable to the conventional massive multiple-input…

Information Theory · Computer Science 2022-02-22 Xuemeng Zhou , Zhiyu Yang , Tianyi Zhang , Yi Jiang

Reconfigurable intelligent surfaces (RIS) is a promising solution to build a programmable wireless environment via steering the incident signal in fully customizable ways with reconfigurable passive elements. In this paper, we consider a…

Signal Processing · Electrical Eng. & Systems 2019-12-30 Huayan Guo , Ying-Chang Liang , Jie Chen , Erik G. Larsson

Beyond diagonal reconfigurable intelligent surface (BD-RIS) architectures offer superior beamforming gain over conventional diagonal RISs. However, the channel estimation overhead is the main hurdle for reaping the above gain in practice.…

Signal Processing · Electrical Eng. & Systems 2026-02-25 Rui Wang , Junyuan Gao , Shuowen Zhang , Bruno Clerckx , Liang Liu

Reconfigurable intelligent surface (RIS) is a newly-emerged technology that, with its unique features, is considered to be a game changer for future wireless networks. Channel estimation is one of the most critical challenges for the…

Signal Processing · Electrical Eng. & Systems 2023-03-30 Mehdi Haghshenas , Parisa Ramezani , Emil Björnson

Reconfigurable intelligent surface (RIS) has recently drawn intensive attention due to its potential of simultaneously realizing high spectral and energy efficiency in a sustainable way. This paper focuses on the design of efficient…

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

Continuous efforts have been devoted to integrate millimeter wave (mmWave) and terahertz (THz) bands into future communication standards in order to overcome the bandwidth shortage problem and achieve high data rates, primarily through…

Signal Processing · Electrical Eng. & Systems 2026-03-05 Sung Hyuck Hong , Junil Choi

Deploying multiple beyond diagonal reconfigurable intelligent surfaces (BD-RISs) can potentially improve the communication performance thanks to inter-element connections of each BD-RIS and inter-surface cooperative beamforming gain among…

Signal Processing · Electrical Eng. & Systems 2026-02-23 Junyuan Gao , Shuowen Zhang , Liang Liu

Channel estimation is challenging for the reconfigurable intelligent surface (RIS)-aided wireless communications. Since the number of coefficients of the cascaded channel among the base station (BS), the RIS and the user equipments (UEs) is…

Signal Processing · Electrical Eng. & Systems 2020-05-19 Chen Hu , Linglong Dai

Reconfigurable intelligent surfaces (RISs) have been proposed recently as new technology to tune the wireless propagation channels in real-time. However, most of the current works assume single-RIS (S-RIS)-aided systems, which can be…

Signal Processing · Electrical Eng. & Systems 2021-09-21 Khaled Ardah , Sepideh Gherekhloo , André L. F. de Almeida , Martin Haardt