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This work investigates a robust resource allocation framework for a downlink multi-user communication system integrating movable antennas (MAs) and reconfigurable intelligent surfaces (RISs) under the rate-splitting multiple access (RSMA)…

Signal Processing · Electrical Eng. & Systems 2026-05-12 Muhammad Asif , Asim Ihsan , Zhongliang Wang , Manzoor Ahmed , Xingwang Li , Arumugam Nallanathan , Symeon Chatzinotas

In this work, in order to achieve higher spectrum efficiency, we propose a reconfigurable intelligent surface (RIS)-assisted multi-user communication uplink system. Different from previous work in which the RIS only optimizes the phase of…

Information Theory · Computer Science 2020-11-19 Liang Yang , Fanxu Meng , Mazen O. Hasna , Ertugrul Basar

This work makes the preliminary contribution of studying the asymptotic performance of a multi-user intelligent reflecting surface (IRS) assisted-multiple-input single-output (MISO) downlink system under imperfect CSI. We first extend the…

Information Theory · Computer Science 2020-08-20 Bayan Al-Nahhas , Qurrat-Ul-Ain Nadeem , Anas Chaaban

We carry out a theoretical analysis of the uplink (UL) of a massive MIMO system with per-user channel correlation and Rician fading, using two processing approaches. Firstly, we examine the linear minimum-mean-square-error receiver under…

Information Theory · Computer Science 2018-09-07 Ikram Boukhedimi , Abla Kammoun , Mohamed-Slim Alouini

As a critical technology for next-generation communication networks, integrated sensing and communication (ISAC) aims to achieve the harmonious coexistence of communication and sensing. The degrees-of-freedom (DoF) of ISAC is limited due to…

Information Theory · Computer Science 2024-10-28 Yongqing Xu , Yong Li , Tony Q. S. Quek

This paper explores an integrated sensing and communication (ISAC) network empowered by multiple active simultaneously transmitting and reflecting reconfigurable intelligent surfaces (STAR-RISs). A base station (BS) furnishes downlink…

Signal Processing · Electrical Eng. & Systems 2025-07-25 Hyeonho Noh , Hyeonsu Lyu , Hyun Jong Yang

Reconfigurable intelligent surfaces (RIS) can be crucial in next-generation communication systems. However, designing the {RIS} phases according to the instantaneous channel state information (CSI) can be challenging in practice due to the…

Information Theory · Computer Science 2023-09-26 Athira Subhash , Abla Kammoun , Ahmed Elzanaty , Sheetal Kalyani , Yazan H. Al-Badarneh , Mohamed-Slim Alouini

In this paper, we consider an active reconfigurable intelligent surface (RIS) to assist the multiuser downlink transmission in the presence of practical hardware impairments (HWIs), including the HWIs at the transceivers and the phase noise…

Signal Processing · Electrical Eng. & Systems 2024-02-19 Zhangjie Peng , Zhibo Zhang , Cunhua Pan , Marco Di Renzo , Octavia A. Dobre , Jiangzhou Wang

We consider the cell-free massive multiple-input multiple-output (MIMO) downlink, where a very large number of distributed multiple-antenna access points (APs) serve many single-antenna users in the same time-frequency resource. A simple…

Information Theory · Computer Science 2017-11-27 Hien Quoc Ngo , Le-Nam Tran , Trung Q. Duong , Michail Matthaiou , Erik G. Larsson

The integration of electromagnetic metasurfaces into wireless communications enables intelligent control of the propagation environment. Recently, flexible intelligent metasurfaces (FIMs) have evolved beyond conventional reconfigurable…

Signal Processing · Electrical Eng. & Systems 2026-01-23 Ling He , Vaibhav Kumar , Anastasios Papazafeiropoulos , Miaowen Wen , Le-Nam Tran , Marwa Chafii

Reconfigurable intelligent surfaces (RIS) as an effective technique for intelligently manipulating channel paths through reflection to serve desired users. Full-duplex (FD) systems, enabling simultaneous transmission and reception from a…

Information Theory · Computer Science 2023-11-08 Li-Hsiang Shen , Chia-Jou Ku , Kai-Ten Feng

We consider a cell-free massive multiple-input multiple-output (MIMO) system with multi-antenna access points and user equipments (UEs) over Weichselberger Rician fading channels with random phase-shifts. More specifically, we investigate…

Information Theory · Computer Science 2022-07-25 Xin Li , Jiayi Zhang , Zhe Wang , Bo Ai , Derrick Wing Kwan Ng

This paper investigates energy efficiency (EE) optimization for an uplink multiuser system assisted by a movable-element reconfigurable intelligent surface (ME-RIS) and a base station equipped with movable antennas (MA-BS). We jointly…

Signal Processing · Electrical Eng. & Systems 2026-03-31 Ayda Nodel Hokmabadi , Mohamed Elhattab , Chadi Assi

In this paper, we explore the integration of low-power, low-cost stacked intelligent metasurfaces (SIM) into cell-free (CF) massive multiple-input multiple-output (mMIMO) systems to enhance access point (AP) capabilities and address high…

Information Theory · Computer Science 2024-09-20 Enyu Shi , Jiayi Zhang , Yiyang Zhu , Jiancheng An , Chau Yuen , Bo Ai

In the intelligent reflecting surface (IRS) assisted communication systems, the acquisition of channel state information (CSI) is a crucial impediment for achieving the passive beamforming gain of IRS because of the considerable overhead…

Information Theory · Computer Science 2020-01-20 Zhaorui Wang , Liang Liu , Shuguang Cui

This paper considers a cell-free massive multipleinput multiple-output (MIMO) integrated sensing and communication (ISAC) system, where distributed MIMO access points (APs) are used to jointly serve the communication users and detect the…

Information Theory · Computer Science 2023-10-16 Mohamed Elfiatoure , Mohammadali Mohammadi , Hien Quoc Ngo , Michail Matthaiou

Reconfigurable Intelligent Surfaces (RIS) are an emerging technology that can be used to reconfigure the propagation environment to improve cellular communication link rates. RIS, which are thin metasurfaces composed of discrete elements,…

Signal Processing · Electrical Eng. & Systems 2020-11-11 Pooja Nuti , Brian L. Evans

Intelligent reflecting surface (IRS) has drawn a lot of attention recently as a promising new solution to achieve high spectral and energy efficiency for future wireless networks. By utilizing massive low-cost passive reflecting elements,…

Information Theory · Computer Science 2022-10-17 Ming-Min Zhao , Qingqing Wu , Min-Jian Zhao , Rui Zhang

Cell-Free Massive Multiple-input Multiple-output (mMIMO) consists of many access points (APs) in a coverage area that jointly serve the users. These systems can significantly reduce the interference among the users compared to conventional…

Information Theory · Computer Science 2021-11-16 Abbas Khalili , Alexei Ashikhmin , Hong Yang

Most works in IRS-assisted systems have ignored the impact of the inevitable residual hardware impairments (HWIs) at both the transceiver hardware and the IRS while any relevant works have addressed only simple scenarios, e.g., with…

Information Theory · Computer Science 2021-09-07 Anastasios Papazafeiropoulos , Cunhua Pan , Pandelis Kourtessis , Symeon Chatzinotas , John M. Senior