On the Design of Broadbeam of Reconfigurable Intelligent Surface

Lin, X., Zhang, L. , Tukmanov, A., Liu, Y., Abbasi, Q. and Imran, M. A. (2024) On the Design of Broadbeam of Reconfigurable Intelligent Surface. IEEE Transactions on Communications, (doi: 10.1109/TCOMM.2024.3354200) (Early Online Publication)

Abstract

Reconfigurable intelligent surface (RIS) has been identified as a promising disruptive innovation to realize a faster, safer and more efficient communication system. In this paper, we study the broad beamwidth design of RIS. A problem is formulated to achieve broadbeam with maximum and equal power gain within a pre-defined angular region given constraints of the unit modulus weights of RIS. Since the formulated problem is non-convex, where the optimal solution cannot be analytically obtained, we propose the difference-of-convex-based semi-definite programming (DC-SDP) algorithm. In addition, as important guidance of signal coverage for arbitrary angular regions, we mathematically derive the relationship between the angular range of the spatial sector and the maximum average received power. The upper bounds of the average received power with different RIS configurations are also obtained, where uniform rectangular array (URA) and uniform linear array (ULA) are considered. Simulation results demonstrate the effectiveness of our derivations and verify that our proposed DC-SDP algorithm is applicable in practical applications and outperforms other baseline methods. Overall, this work can be viewed as a foundation for the practical implementation of RIS on coverage enhancement and can also be seen as an initial step towards achieving channel estimation.

• Item Type: Articles
• Additional Information: This work was supported in part by the U.K. Engineering and Physical Sciences Research Council (EPSRC) with British Telecom.
• Status: Early Online Publication
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Liu, Yihong and Zhang, Professor Lei and Imran, Professor Muhammad and Tukmanov, Dr Anvar and Lin, Ms Xinyi and Abbasi, Professor Qammer
• Authors: Lin, X., Zhang, L., Tukmanov, A., Liu, Y., Abbasi, Q., and Imran, M. A.
• College/School: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity; College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: IEEE Transactions on Communications
• Publisher: IEEE
• ISSN: 0090-6778
• ISSN (Online): 1558-0857
• Published Online: 15 January 2024
• Copyright Holders: Copyright © 2024 IEEE
• First Published: First published in IEEE Transactions on Communications 2024
• Publisher Policy: Reproduced in accordance with the publisher copyright policy