English
Related papers

Related papers: Statistically Optimal Beamforming and Ergodic Capa…

200 papers

Benefiting from its capability to generalize existing reconfigurable intelligent surface (RIS) architectures and provide additional design flexibility via interactions between RIS elements, beyond-diagonal RIS (BD-RIS) has attracted…

Signal Processing · Electrical Eng. & Systems 2025-01-20 Xiaohua Zhou , Tianyu Fang , Yijie Mao

Reconfigurable intelligent surface (RIS)-aided rate-splitting multiple access (RSMA) systems have demonstrated remarkable potential in enhancing spectral efficiency. However, most existing works rely on ideal hardware, which is…

Information Theory · Computer Science 2026-03-20 Xuejun Cheng , Qian Zhang , Yunnuo Xu , Zheng Dong , Ju Liu , Bruno Clerckx

Reconfigurable intelligent surface (RIS) is a newly-emerged technology that might fundamentally change how wireless networks are operated. Though extensively studied in recent years, the practical limitations of RIS are often neglected when…

Signal Processing · Electrical Eng. & Systems 2023-12-12 Parisa Ramezani , Yasaman Khorsandmanesh , Emil Björnson

The opportunistic beamforming in the downlink of multiple-input single-output (MISO) systems forms $N$ transmit beams, usually, no more than the number of transmit antennas $N_t$. However, the degrees of freedom in this downlink is as large…

Information Theory · Computer Science 2009-01-05 Minghua Xia , Wenkun Wen , Soo-Chang Kim

This paper investigates the performance of reconfigurable intelligent surface (RIS)-aided massive multiple-input multiple-output (MIMO) systems with direct links, and the phase shifts of the RIS are designed based on the statistical channel…

Information Theory · Computer Science 2021-02-16 Kangda Zhi , Cunhua Pan , Hong Ren , Kezhi Wang

Reconfigurable intelligent surfaces (RIS)-assisted massive multiple-input multiple-output (mMIMO) is a promising technology for applications in next-generation networks. However, reflecting-only RIS provides limited coverage compared to a…

Information Theory · Computer Science 2023-09-18 Anastasios Papazafeiropoulos , Le-Nam Tran , Zaid Abdullah , Pandelis Kourtessis , Symeon Chatzinotas

A fluid reconfigurable intelligent surface (fRIS)-aided integrated sensing and communication (ISAC) system is proposed to enhance multi-target sensing and multi-user communication. Unlike the conventional RIS, the fRIS employs movable…

Signal Processing · Electrical Eng. & Systems 2026-01-08 Junjie Ye , Peichang Zhang , Xiao-Peng Li , Lei Huang , Yuanwei Liu

In the paper, the physical-layer security for reconfigurable intelligent surface (RIS) aided integrated sensing and communication (ISAC) system is studied. There is an active eavesdropper (AE) as well as a passive eavesdropper (PE), and…

Information Theory · Computer Science 2026-05-11 Yueyi Dong , Tian Zhang

Mutual Coupling (MC) is an unavoidable feature in Reconfigurable Intelligent Surfaces (RISs) with sub-wavelength inter-element spacing. Its inherent presence naturally leads to non-local RIS structures, which can be efficiently described…

Information Theory · Computer Science 2024-04-09 Dilki Wijekoon , Amine Mezghani , George C. Alexandropoulos , Ekram Hossain

Reconfigurable Intelligent Surfaces (RIS) or Intelligent Reflecting Surfaces (IRS) are metasurfaces that can be deployed in various places in wireless environments to make these environments controllable and reconfigurable. In this paper,…

Information Theory · Computer Science 2020-01-22 S. Mohammad Razavizadeh , Tommy Svensson

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

Simultaneously reflecting and transmitting reconfigurable intelligent surfaces (STAR-RIS) has recently emerged as prominent technology that exploits the transmissive property of RIS to mitigate the half-space coverage limitation of…

Signal Processing · Electrical Eng. & Systems 2024-04-01 Muhammad Faraz Ul Abrar , Muhammad Talha , Rafay Iqbal Ansari , Syed Ali Hassan , Haejoon Jung

Active reconfigurable intelligent surface (RIS) is a new RIS architecture that can reflect and amplify communication signals. It can provide enhanced performance gain compared to the conventional passive RIS systems that can only reflect…

Information Theory · Computer Science 2024-01-12 Qian Zhang , Mingjie Shao , Qiang Li , Ju Liu

In this letter, we derive an expression for the achievable rate in a multiple-input multiple-output (MIMO) system assisted by a beyond-diagonal reconfigurable intelligent surface (BD-RIS) when the channels to and from the BD-RIS are…

Information Theory · Computer Science 2025-04-11 Ignacio Santamaria , Jesus Gutierrez , Mohammad Soleymani , Eduard Jorswieck

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

This paper considers downlink of reconfigurable intelligent surface (RIS) assisted cooperative non-orthogonal multiple access (CNOMA) systems. Our objective is to minimize the total transmit power by jointly optimizing the active…

Signal Processing · Electrical Eng. & Systems 2020-12-08 Jiakuo Zuo , Yuanwei Liu , Naofal Al-Dhahir

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 investigates the problem of resource allocation for multiuser communication networks with a reconfigurable intelligent surface (RIS)-assisted wireless transmitter. In this network, the sum transmit power of the network is…

Signal Processing · Electrical Eng. & Systems 2020-09-25 Zhaohui Yang , Wei Xu , Chongwen Huang , Jianfeng Shi , Mohammad Shikh-Bahaei

Reconfigurable intelligent surface (RIS) has entered the public consciousness as a promising technology for enhancing the performance of future wireless communication systems by dynamically constructing the wireless channels. In this…

Information Theory · Computer Science 2023-03-02 Pingping Zhang , Shiqi Gong , Shaodan Ma

In this paper, a discrete reconfigurable intelligent surface (RIS)-assisted spatial shift keying (SSK) multiple-input multiple-output (MIMO) scheme is investigated, in which a direct link between the transmitter and the receiver is…

Information Theory · Computer Science 2024-11-04 Xusheng Zhu , Qingqing Wu , Wen Chen , Xinyuan He , Lexi Xu , Yaxin Zhang