English
Related papers

Related papers: Phase Shift Design for RIS-Aided Cell-Free Massive…

200 papers

Downlink reconfigurable intelligent surface (RIS)-assisted multi-input-multi-output (MIMO) systems are considered with far-field, near-field, and hybrid-far-near-field channels. According to the angular or distance information contained in…

Information Theory · Computer Science 2023-10-03 Suyu Lv , Yuanwei Liu , Xiaodong Xu , Arumugam Nallanathan , A. Lee Swindlehurst

This work studies the net sum-rate performance of a distributed reconfigurable intelligent surfaces (RISs)-assisted multi-user multiple-input-single-output (MISO) downlink communication system under imperfect instantaneous-channel state…

Signal Processing · Electrical Eng. & Systems 2023-08-10 Bayan Al-Nahhas , Qurrat-UI-Ain Nadeem , Aryan Kaushik , Anas Chaaban

Transmissive reconfigurable intelligent surfaces (RIS) represent a transformative architecture for future wireless networks, enabling a paradigm shift from traditional costly base stations to low-cost, energy-efficient transmitters. This…

Information Theory · Computer Science 2025-11-17 Zhengwei Jiang , Yufeng Zhou , Xusheng Zhu , Wen Chen , Qingqing Wu , Kai-Kit Wong

In this letter, we present in detail the system-level modeling of reconfigurable intelligent surface (RIS)-assisted cellular systems by considering a 3-dimensional channel model between base station, RIS, and user. We prove that the optimal…

Information Theory · Computer Science 2023-05-03 Pavan Reddy M. , SaiDhiraj Amuru , Kiran Kuchi

We present efficient algorithms for the sum-spectral efficiency (SE) maximization of the multi-user reconfigurable intelligent surface (RIS)-aided multiple-input multiple-output (MIMO) broadcast channel based on a zero-forcing approach.…

Information Theory · Computer Science 2023-11-21 Dominik Semmler , Michael Joham , Wolfgang Utschick

Reconfigurable intelligent surfaces (RISs) have emerged as a promising solution that can provide dynamic control over the propagation of electromagnetic waves. The RIS technology is envisioned as a key enabler of sixth-generation networks…

Signal Processing · Electrical Eng. & Systems 2025-02-26 Ishan Koralege , Arthur S. de Sena , Nurul H. Mahmood , Farjam Karim , Dimuthu Lesthuruge , Samitha Gunarathne

An innovative evolutionary method for the dynamic control of reconfigurable intelligent surfaces (RISs) is proposed. It leverages, on the one hand, on the exploration capabilities of evolutionary strategies and their effectiveness in…

Systems and Control · Electrical Eng. & Systems 2023-09-11 Francesco Zardi , Giacomo Oliveri , Andrea Massa

A reconfigurable intelligent surface (RIS) is a planar surface that can enhance the quality of communication by providing control over the communication environment. Reflection optimization is one of the pivotal challenges in RIS setups.…

Information Theory · Computer Science 2024-11-26 Seyedkhashayar Hashemi , Masoud Ardakani , Hai Jiang

Reconfigurable intelligent surface (RIS) is a novel meta-material which can form a smart radio environment by dynamically altering reflection directions of the impinging electromagnetic waves. In the prior literature, the inter-RIS links…

Information Theory · Computer Science 2024-03-13 Kaizhe Xu , Jiajia Guo , Jun Zhang , Shi Jin , Shaodan Ma

We propose an alternating optimization framework for maximizing energy efficiency (EE) in reconfigurable intelligent surface (RIS) assisted distributed MIMO (D-MIMO) systems under both coherent and non-coherent reception modes. The…

This work studies a low-complexity design for reconfigurable intelligent surface (RIS)-aided multiuser multiple-input multiple-output systems. The base station (BS) applies receive antenna selection to connect a subset of its antennas to…

Signal Processing · Electrical Eng. & Systems 2022-12-29 Chongjun Ouyang , Ali Bereyhi , Saba Asaad , Ralf R. Müller , Hongwen Yang

In this paper, we study the transmission design for reconfigurable intelligent surface (RIS)-aided multiuser communication networks. Different from most of the existing contributions, we consider long-term CSI-based transmission design,…

Information Theory · Computer Science 2021-11-25 Hong Ren , Cunhua Pan , Liang Wang , Zhoubing Kou , Kezhi Wang

This work studies the net sum-rate performance of a distributed reconfigurable intelligent surfaces (RISs)-assisted multi-user multiple-input-single-output (MISO) downlink communication system under imperfect instantaneous-channel state…

Information Theory · Computer Science 2023-07-04 Bayan Al-Nahhas , Qurrat-Ul-Ain Nadeem , Anas Chaaban

It is challenging to precisely configure the phase shifts of the reflecting elements at the reconfigurable intelligent surface (RIS) due to inherent hardware impairments (HIs). In this paper, the mean square error (MSE) performance is…

Information Theory · Computer Science 2022-08-17 Jingwen Zhao , Ming Chen , Cunhua Pan , Zhiyang Li , Gui Zhou , Xiao Chen

Antenna selection is capable of reducing the hardware complexity of massive multiple-input multiple-output (MIMO) networks at the cost of certain performance degradation. Reconfigurable intelligent surface (RIS) has emerged as a…

Information Theory · Computer Science 2020-09-17 Jinglian He , Kaiqiang Yu , Yuanming Shi , Yong Zhou , Wei Chen , Khaled B. Letaief

Active reconfigurable intelligent surfaces (RISs) employ amplification to overcome attenuation caused by the RIS cascaded link. In this paper, we analyze the effects of phase errors and channel aging in active simultaneously transmitting…

Information Theory · Computer Science 2025-10-16 Jun Qian , Ross Murch , Khaled B. Letaief

Reducing computational complexity is crucial in optimizing the phase shifts of Intelligent Reflecting Surface (IRS) systems since IRS-assisted communication systems are generally deployed with a large number of reflecting elements (REs).…

Information Theory · Computer Science 2022-04-12 Ahmad Sirojuddin , Dony Darmawan Putra , Wan-Jen Huang

This paper investigates the integration of beyond-diagonal reconfigurable intelligent surfaces (BD-RISs) into cell-free massive multiple-input multiple-output (CF-mMIMO) systems, focusing on applications involving simultaneous wireless…

Information Theory · Computer Science 2025-08-21 Thien Duc Hua , Mohammadali Mohammadi , Hien Quoc Ngo , Michail Matthaiou

In this paper, we focus our attention on the mitigation of beam squint for reconfigurable intelligent surface (RIS) aided wideband millimeter wave (mmWave) communications. Due to the intrinsic passive property, the phase shifts of all…

Information Theory · Computer Science 2021-03-23 Yun Chen , Da Chen , Tao Jiang

We consider a reconfigurable intelligent surface (RIS) assisted multiple-input multiple-output (MIMO) system in the presence of scattering objects. The MIMO transmitter and receiver, the RIS, and the scattering objects are modeled as…

Information Theory · Computer Science 2023-09-19 H. El Hassani , X. Qian , S. Jeong , N. S. Perović , M. Di Renzo , P. Mursia , V. Sciancalepore , X. Costa-Pérez