TY - JOUR
T1 - Reconfigurable Intelligent Surfaces in 6G
T2 - Reflective, Transmissive, or Both?
AU - Zeng, Shuhao
AU - Zhang, Hongliang
AU - Di, Boya
AU - Tan, Yunhua
AU - Han, Zhu
AU - Poor, H. Vincent
AU - Song, Lingyang
N1 - Funding Information:
Manuscript received February 10, 2021; accepted February 22, 2021. Date of publication February 26, 2021; date of current version June 10, 2021. This work was supported in part by the National Natural Science Foundation of China under Grants 61625101, 61829101, and 61941101, and in part by the U.S. National Science Foundation under Grants EARS-1839818, CNS-1717454, CNS-1731424, CNS-1702850, and CCF-1908308. The associate editor coordinating the review of this letter and approving it for publication was C. You. (Corresponding author: Lingyang Song.) Shuhao Zeng, Yunhua Tan, and Lingyang Song are with the Department of Electronics, Peking University, Beijing 100871, China (e-mail: shuhao.zeng@pku.edu.cn; tanggeric@pku.edu.cn; lingyang.song@ pku.edu.cn). Hongliang Zhang and H. Vincent Poor are with the Department of Electrical Engineering, Princeton University, Princeton, NJ 08544 USA (e-mail: hongliang.zhang92@gmail.com; poor@princeton.edu). Boya Di is with the Department of Computing, Imperial College London, London SW7 2AZ, U.K. (e-mail: diboya92@gmail.com). Zhu Han is with the Department of Electrical and Computer Engineering, B. Reconfigurable Intelligent Surfaces mentofComputerScienceand Engineering,Kyung HeeUniversity,SeoulUniversityofHouston,Houston,TX77004USA,andalsowiththeDepart- An RIS is composed of M × N sub-wavelength elements, 02447,SouthKorea(e-mail:zhan2@uh.edu). each with the size of lM × lN. As shown in Fig. 1, each Digital Object Identifier 10.1109/LCOMM.2021.3062615 element has several PIN diodes onboard. When the biased 1558-2558 © 2021 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission. See https://www.ieee.org/publications/rights/index.html for more information.
Publisher Copyright:
© 1997-2012 IEEE.
PY - 2021/6
Y1 - 2021/6
N2 - Reconfigurable intelligent surfaces (RISs) have attracted wide interest from industry and academia since they can shape the wireless environment into a desirable form at low cost. In practice, RISs have three types of implementations: 1) reflective, where signals can be reflected to the users on the same side of the base station (BS), 2) transmissive, where signals can penetrate the RIS to serve the users on the opposite side of the BS, and 3) hybrid, where the RISs have a dual function of reflection and transmission. Most existing works focus on the reflective type RISs, and the other two types of RISs have not been well investigated. In this letter, a downlink multi-user RIS-assisted communication network is considered, where the RIS can be one of these types. We derive the system sum-rate, and discuss which type can yield the best performance under a specific user distribution. Numerical results verify our analysis.
AB - Reconfigurable intelligent surfaces (RISs) have attracted wide interest from industry and academia since they can shape the wireless environment into a desirable form at low cost. In practice, RISs have three types of implementations: 1) reflective, where signals can be reflected to the users on the same side of the base station (BS), 2) transmissive, where signals can penetrate the RIS to serve the users on the opposite side of the BS, and 3) hybrid, where the RISs have a dual function of reflection and transmission. Most existing works focus on the reflective type RISs, and the other two types of RISs have not been well investigated. In this letter, a downlink multi-user RIS-assisted communication network is considered, where the RIS can be one of these types. We derive the system sum-rate, and discuss which type can yield the best performance under a specific user distribution. Numerical results verify our analysis.
KW - Reconfigurable intelligent surfaces
KW - sum-rate analysis
KW - type selection
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U2 - 10.1109/LCOMM.2021.3062615
DO - 10.1109/LCOMM.2021.3062615
M3 - Article
AN - SCOPUS:85101795335
SN - 1089-7798
VL - 25
SP - 2063
EP - 2067
JO - IEEE Communications Letters
JF - IEEE Communications Letters
IS - 6
M1 - 9365009
ER -