English
Related papers

Related papers: Two-Timescale Joint Precoding Design and RIS Optim…

200 papers

This study proposes a novel precoding scheme for multiuser multiple-input multiple-output (MIMO) relay systems in the presence of imperfect channel state information (CSI). The base station (BS) and the MIMO relay station (RS) are both…

Information Theory · Computer Science 2014-12-18 Y. Cai , R. C. de Lamare , L. L. Yang , M. Zhao

Reconfigurable intelligent Surfaces (RIS) and half-duplex decoded and forwarded (DF) relays can collaborate to optimize wireless signal propagation in communication systems. Users typically have different rate demands and are clustered into…

Information Theory · Computer Science 2025-06-04 Huijun Tang , Jieling Zhang , Zhidong Zhao , Huaming Wu , Hongjian Sun , Pengfei Jiao

This paper introduces two machine learning optimization algorithms to significantly enhance position estimation in Reconfigurable Intelligent Surface (RIS) aided localization for mobile user equipment in Non-Line-of-Sight conditions.…

Signal Processing · Electrical Eng. & Systems 2024-05-06 Rafael A. Aguiar , Nuno Paulino , Luís M. Pessoa

Reconfigurable intelligent surface (RIS) is an emerging technology to enhance wireless communication in terms of energy cost and system performance by equipping a considerable quantity of nearly passive reflecting elements. This study…

Information Theory · Computer Science 2021-03-17 Jun Zhang , Jie Liu , Shaodan Ma , Chao-Kai Wen , Shi Jin

Integrating reconfigurable intelligent surfaces (RIS) into wireless communication systems is a promising approach for enhancing coverage and data rates by intelligently redirecting signals, through a process known as beamforming. However,…

Systems and Control · Electrical Eng. & Systems 2025-08-26 Luis C. Mathias , Atefeh Termehchi , Taufik Abrão , Ekram Hossain

In reconfigurable intelligent surface (RIS)-assisted wireless communication systems, the pointing accuracy and intensity of reflections depend crucially on the 'profile,' representing the amplitude/phase state information of all elements in…

Signal Processing · Electrical Eng. & Systems 2023-09-12 Wei Wang , Peizheng Li , Angela Doufexi , Mark A Beach

Reconfigurable intelligent surfaces (RISs) have recently attracted interest for non-terrestrial networks (NTNs), especially for improving satellite communication performance. However, RIS-assisted urban NTN designs that jointly support…

Signal Processing · Electrical Eng. & Systems 2026-04-22 Muhammad Khalil , Ke Wang , Jinho Choi

Reconfigurable intelligent surface (RIS) is a promising technology to enhance the spectral and energy efficiency in a wireless communication system. The design of the phase shifts of an RIS in every channel coherence interval demands a huge…

Signal Processing · Electrical Eng. & Systems 2024-05-15 Sadaf Syed , Dominik Semmler , Donia Ben Amor , Michael Joham , Wolfgang Utschick

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

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

Reconfigurable intelligent surface (RIS) is a promising technology for future wireless communication systems. Conventional RIS is constrained to a diagonal scattering matrix, which limits its flexibility. Recently, beyond-diagonal RIS…

Signal Processing · Electrical Eng. & Systems 2026-03-17 Zheyu Wu , Matteo Nerini , Bruno Clerckx

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

Reconfigurable intelligent surfaces (RISs) can improve the capacity of wireless communication links by passively beamforming the impinging signals in desired directions. This feature has been demonstrated both analytically and…

Signal Processing · Electrical Eng. & Systems 2025-01-23 Emil Björnson , Özlem Tuğfe Demir

This paper investigates the problem of resource allocation for a wireless communication network with distributed reconfigurable intelligent surfaces (RISs). In this network, multiple RISs are spatially distributed to serve wireless users…

Signal Processing · Electrical Eng. & Systems 2020-05-04 Zhaohui Yang , Mingzhe Chen , Walid Saad , Wei Xu , Mohammad Shikh-Bahaei , H. Vincent Poor , Shuguang Cui

The conventional beam management procedure mandates that the user equipment (UE) periodically measure the received signal reference power (RSRP) and transmit these measurements to the base station (BS). The challenge lies in balancing the…

Systems and Control · Electrical Eng. & Systems 2023-10-31 Junshuo Liu , Rujing Xiong , Jialong Lu , Tiebin Mi , Robert C. Qiu

Existing works mainly rely on the far-field planar-wave-based channel model to assess the performance of reconfigurable intelligent surface (RIS)-enabled wireless communication systems. However, when the transmitter and receiver are in…

Signal Processing · Electrical Eng. & Systems 2024-03-20 Hao Jiang , Wangqi Shi , Zaichen Zhang , Cunhua Pan , Qingqing Wu , Feng Shu , Ruiqi Liu , Jiangzhou Wang

Considering the dimensionality of a typical reconfigurable intelligent surface (RIS), channel state information acquisition in RIS-assisted systems requires lengthy pilot transmissions. Moreover, the large aperture of the RIS may cause…

Signal Processing · Electrical Eng. & Systems 2023-12-27 Mehdi Haghshenas , Parisa Ramezani , Maurizio Magarini , Emil Björnson

Reconfigurable intelligent surfaces (RISs) have been recently considered as a promising candidate for energy-efficient solutions in future wireless networks. Their dynamic and lowpower configuration enables coverage extension, massive…

Information Theory · Computer Science 2021-07-22 Li Wei , Chongwen Huang , Qinghua Guo , Zhaoyang Zhang , Merouane Debbah , Chau Yuen

We consider the extra degree of freedom offered by the rotation of the reconfigurable intelligent surface (RIS) plane and investigate its potential in improving the performance of RIS-assisted wireless communication systems. By considering…

Information Theory · Computer Science 2022-02-14 Yajun Cheng , Wei Peng , Chongwen Huang , George C. Alexandropoulos , Chau Yuen , Mérouane Debbah

This paper explores the near field (NF) covert communication with the aid of rate-splitting multiple access (RSMA) and reconfigurable intelligent surfaces (RIS). In particular, the RIS operates in the NF of both the legitimate user and the…

Signal Processing · Electrical Eng. & Systems 2025-07-30 Atiquzzaman Mondal , Amira Bendaimi , Huseyin Arslan