English
Related papers

Related papers: On Channel Estimation for Group-Connected Beyond D…

200 papers

Reconfigurable intelligent surface (RIS) is envisioned to be an essential component of the paradigm for beyond 5G networks as it can potentially provide similar or higher array gains with much lower hardware cost and energy consumption…

Information Theory · Computer Science 2020-07-09 Hang Liu , Xiaojun Yuan , Ying-Jun Angela Zhang

The beyond-diagonal reconfigurable intelligent surface (BD-RIS) is a recent architecture in which scattering elements are interconnected to enhance the degrees of freedom for wave control, yielding performance gains over traditional…

Signal Processing · Electrical Eng. & Systems 2026-03-17 Gilderlan Tavares de Araújo , André L. F. de Almeida , Buno Sokal , Gabor Fodor

Extremely large-scale reconfigurable intelligent surfaces (XL-RISs) have emerged as a promising technology for millimeter-wave (mmWave) communications. However, the exceedingly large aperture of XL-RISs renders the RIS-user links likely to…

Information Theory · Computer Science 2026-05-11 Erkang Dong , Taihao Zhang , Cunhua Pan , Hong Ren , Jiangzhou Wang

In this paper, we adopt a three-stage based uplink channel estimation protocol with reduced pilot overhead for an reconfigurable intelligent surface (RIS)-aided multi-user (MU) millimeter wave (mmWave) communication system, in which both…

Signal Processing · Electrical Eng. & Systems 2023-04-18 Zhendong Peng , Gui Zhou , Cunhua Pan , Hong Ren , A. Lee Swindlehurst , Petar Popovski , Gang Wu

Reconfigurable Intelligent Surfaces (RISs) have been recently considered as an energy-efficient solution for future wireless networks due to their fast and low-power configuration, which has increased potential in enabling massive…

Information Theory · Computer Science 2022-06-27 Li Wei , Chongwen Huang , George C. Alexandropoulos , Chau Yuen , Zhaoyang Zhang , Mérouane Debbah

Reconfigurable Intelligent Surface (RIS) panels are envisioned as a key technology for sixth-generation (6G) wireless networks, providing a cost-effective means to enhance coverage and spectral efficiency. A critical challenge is the…

Signal Processing · Electrical Eng. & Systems 2025-12-16 Saifur Rahman , Syed Luqman Shah , Salman Khan , Jalal Khan , Muhammad Irfan , Maaz Shafi , Said Muhammad , Fazal Muhammad , Mohammad Shahed Akond

Channel estimation in reconfigurable intelligent surfaces (RIS)-aided systems is crucial for optimal configuration of the RIS and various downstream tasks such as user localization. In RIS-aided systems, channel estimation involves…

Signal Processing · Electrical Eng. & Systems 2023-12-19 Firas Fredj , Amal Feriani , Amine Mezghani , Ekram Hossain

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

Beyond diagonal reconfigurable intelligent surface (BD-RIS), with its enhanced degrees of freedom compared to conventional RIS, has demonstrated notable potential for enhancing wireless communication performance. However, a key challenge in…

Signal Processing · Electrical Eng. & Systems 2025-09-15 Yijie Liu , Weidong Mei , He Sun , Dong Wang , Peilan Wang

Channel estimation is challenging for the reconfigurable intelligence surface (RIS) assisted millimeter wave (mmWave) communications. Since the number of coefficients of the cascaded channels in such systems is closely dependent on the…

Signal Processing · Electrical Eng. & Systems 2021-06-22 Yushan Liu , Shun Zhang , Feifei Gao , Jie Tang , Octavia A. Dobre

Reconfigurable intelligent surfaces (RISs) consist of many passive elements of metamaterials whose impedance can be controllable to change the characteristics of wireless signals impinging on them. Channel estimation is a critical task when…

Information Theory · Computer Science 2023-09-14 Özlem Tuğfe Demir , Emil Björnson

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

Reconfigurable intelligent surfaces (RISs) have been proposed as a key enabler to improve the coverage of the signals and mitigate the frequent blockages in millimeter wave (mmWave) multiple-input multiple-output (MIMO) communications.…

Signal Processing · Electrical Eng. & Systems 2021-07-16 Rafaela Schroeder , Jiguang He , Glauber Brante , Markku Juntti

To achieve the more significant passive beamforming gain in the double-intelligent reflecting surface (IRS) aided system over the conventional single-IRS counterpart, channel state information (CSI) is indispensable in practice but also…

Information Theory · Computer Science 2021-03-12 Beixiong Zheng , Changsheng You , Rui Zhang

Reconfigurable intelligent surface (RIS) is a promising candidate technology for the upcoming Sixth Generation (6G) communication system for its ability to manipulate the wireless communication environment by controlling the coefficients of…

Information Theory · Computer Science 2023-09-29 Haochen Li , Zhiwen Pan , Bin Wang , Nan Liu , Xiaohu You

Beyond diagonal reconfigurable intelligent surface (BD-RIS) extends conventional RIS through novel architectures, such as group-connected RIS, with scattering matrix not restricted to being diagonal. However, it remains unexplored how to…

Information Theory · Computer Science 2024-05-08 Matteo Nerini , Shanpu Shen , Bruno Clerckx

The channel estimation problem has been widely discussed in traditional reconfigurable intelligent surface assisted multiple-input multiple-output. However, solutions for channel estimation adapted to beyond diagonal RIS need further study,…

Signal Processing · Electrical Eng. & Systems 2024-12-05 Gilderlan T de Araujo , Andre L. F. de Almeida

Beyond-diagonal reconfigurable intelligent surface (BD-RIS) has been proposed recently as a novel and generalized RIS architecture that offers enhanced wave manipulation flexibility and large coverage expansion. However, the beyond-diagonal…

Information Theory · Computer Science 2023-12-27 Tianyu Fang , Yijie Mao

In reconfigurable intelligent surface (RIS)-assisted millimeter-wave (mmWave) communication systems, the large-scale RIS introduces pronounced geometric effects that lead to the coexistence of far-field and near-field propagation.…

Signal Processing · Electrical Eng. & Systems 2026-02-09 Xiaokun Tuo , Ming-Min Zhao , Xiang Wang , Changsheng You , Min-Jian Zhao

In this paper, we investigate cascaded channel estimation for reconfigurable intelligent surface (RIS)-aided millimeter-wave multi-user communication systems. Since the complex channel gains of the cascaded RIS channel are generally…

Signal Processing · Electrical Eng. & Systems 2025-10-21 Gyoseung Lee , Junil Choi