English
Related papers

Related papers: Outage Performance Analysis of HARQ-Aided Multi-RI…

200 papers

Integrated sensing and communication (ISAC) has been envisioned as a promising technique to alleviate the spectrum congestion problem. Inspired by the applications of reconfigurable intelligent surface (RIS) in dynamically manipulating…

Signal Processing · Electrical Eng. & Systems 2023-02-23 Honghao Luo , Rang Liu , Ming Li , Qian Liu

This paper provides a theoretical framework for understanding the performance of reconfigurable intelligent surface (RIS)-aided massive multiple-input multiple-output (MIMO) with zero-forcing (ZF) detectors under imperfect channel state…

Information Theory · Computer Science 2021-11-03 Kangda Zhi , Cunhua Pan , Gui Zhou , Hong Ren , Maged Elkashlan , Robert Schober

In this letter, we investigate a cell-free network aided by hybrid reconfigurable intelligent surfaces (RISs), which consists of a mixture of passive and active elements that are capable of amplifying and reflecting the incident signal. To…

Signal Processing · Electrical Eng. & Systems 2022-10-05 Wanting Lyu , Yue Xiu , Songjie Yang , Chau Yuen , Zhongpei Zhang

This letter studies the throughput and the outage probability of spectrum sharing networks utilizing hybrid automatic repeat request (HARQ) feedback. We focus on the repetition time diversity and the incremental redundancy HARQ protocols…

Information Theory · Computer Science 2013-10-16 Behrooz Makki , Alexandre Graell i Amat , Thomas Eriksson

In this paper, we study the performance of wireless communications empowered by Reconfigurable Intelligent Surface (RISs) over Nakagami-m fading channels. We consider two phase configuration designs for the RIS, one random and another one…

Information Theory · Computer Science 2023-09-22 Dimitris Selimis , Kostas P. Peppas , George C. Alexandropoulos , Fotis I. Lazarakis

A reconfigurable intelligent surface (RIS) is a nearly-passive flat layer made of inexpensive elements that can add a tunable phase shift to the impinging electromagnetic wave and are controlled by a low-power electronic circuit. This paper…

Signal Processing · Electrical Eng. & Systems 2022-05-04 Stefano Buzzi , Emanuele Grossi , Marco Lops , Luca Venturino

This paper focuses on the design of transmission methods and reflection optimization for a wireless system assisted by a single or multiple reconfigurable intelligent surfaces (RISs). The existing techniques are either too complex to…

Information Theory · Computer Science 2023-09-13 Wei Jiang , Hans D. Schotten

Inexpensive tags powered by energy harvesting (EH) can realize green (energy-efficient) Internet of Things (IoT) networks. However, tags are vulnerable to energy insecurities, resulting in poor communication ranges, activation distances,…

Signal Processing · Electrical Eng. & Systems 2023-09-19 Diluka Galappaththige , Fatemeh Rezaei , Chintha Tellambura , Sanjeewa Herath

We propose a reconfigurable intelligent surface (RIS)-assisted underlay spectrum sharing system, in which a RIS-assisted secondary network shares the spectrum licensed for a primary network. The secondary network consists of a secondary…

Information Theory · Computer Science 2024-04-23 Yazan H. Al-Badarneh , Mustafa K. Alshawaqfeh , Osamah S. Badarneh , Yazid M. Khattabi

Reconfigurable intelligent surface (RIS) is a promising technology that can reshape the electromagnetic environment in wireless networks, offering various possibilities for enhancing wireless channels. Motivated by this, we investigate the…

Information Theory · Computer Science 2024-09-02 Shengguo Meng , Wankai Tang , Weicong Chen , Jifeng Lan , Qun Yan Zhou , Yu Han , Xiao Li , Shi Jin

Intelligent reflecting surface (IRS) is envisioned to play a significant role in future wireless communication systems thanks to its powerful capability of enabling smart and reconfigurable radio environment. In this paper, we study the…

Information Theory · Computer Science 2021-02-23 Weidong Mei , Rui Zhang

We address the reflection optimization problem for a reconfigurable intelligent surface (RIS), where the RIS elements feature a set of non-uniformly spaced discrete phase shifts. This is motivated by the actual behavior of practical RIS…

Information Theory · Computer Science 2023-11-14 Seyedkhashayar Hashemi , Hai Jiang , Masoud Ardakani

This paper investigates the system spectral efficiency (SE) in reconfigurable intelligent surface (RIS)-aided multiuser multiple-input single-output (MISO) systems, where RIS can reconfigure the propagation environment via a large number of…

Information Theory · Computer Science 2020-01-31 Yulan Gao , Chao Yong , Zehui Xiong , Dusit Niyato , Yue Xiao , Jun Zhao

Active reconfigurable intelligent surfaces (RISs) have recently been proposed to compensate for the severe multiplicative fading effect of conventional passive RIS-aided systems. Each reflecting element of active RISs is assisted by an…

Information Theory · Computer Science 2023-02-21 Gui Zhou , Cunhua Pan , Hong Ren , Dongfang Xu , Zaichen Zhang , Jiangzhou Wang , Robert Schober

Practical hardware limitations often impose a reduced number of available phase shifts at the elements of a reconfigurable intelligent surface (RIS). Most works often assume continuous phase-shits at the RIS elements for the transmit and…

Information Theory · Computer Science 2023-04-20 Nuno Souto

Reconfigurable intelligent surfaces (RIS) have drawn considerable attention recently due to their controllable scattering elements that are able to direct electromagnetic waves into desirable directions. Although RISs share some…

Information Theory · Computer Science 2021-04-08 Mohanad Obeed , Anas Chaaban

A hardware model for active simultaneously transmitting and reflecting reconfigurable intelligent surfaces (STAR-RISs) is proposed consisting of reflection-type amplifiers. The amplitude gains of the STAR element are derived for both…

Signal Processing · Electrical Eng. & Systems 2023-02-10 Jiaqi Xu , Jiakuo Zuo , Joey Tianyi Zhou , Yuanwei Liu

Reconfigurable intelligent surface (RIS) has emerged as a promising technology for improving capacity and extending coverage of wireless networks. In this work, we consider RIS-aided millimeter wave (mmWave) multiple-input and…

Information Theory · Computer Science 2023-04-17 Yabo Guo , Peng Sun , Zhengdao Yuan , Qinghua Guo , Zhongyong Wang

With the rapid development of Internet of Things (IoT), massive machine-type communication has become a promising application scenario, where a large number of devices transmit sporadically to a base station (BS). Reconfigurable intelligent…

Information Theory · Computer Science 2021-01-26 Shuhao Xia , Yuanming Shi , Yong Zhou , Xiaojun Yuan

Reconfigurable intelligent surface (RIS) has become a focal point of extensive research due to its remarkable "squared gain". However, achieving a substantial beamforming gain typically requires a significant number of elements, which leads…

Information Theory · Computer Science 2023-11-20 Hao Xie , Dong Li