Cooperative Rotatable IRSs for Wireless Communications: Joint Beamforming and Orientation Optimization

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Peng, Qiaoyan, Wu, Qingqing, Chen, Guangji, Chen, Wen, Shen, Shanpu, Ma, Shaodan
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908714517135360
author Peng, Qiaoyan
Wu, Qingqing
Chen, Guangji
Chen, Wen
Shen, Shanpu
Ma, Shaodan
author_facet Peng, Qiaoyan
Wu, Qingqing
Chen, Guangji
Chen, Wen
Shen, Shanpu
Ma, Shaodan
contents Rotatable intelligent reflecting surfaces (IRSs) introduce a new degree of freedom (DoF) for shaping wireless propagation by adaptively adjusting the orientation of IRSs. This paper considers an angle-dependent reflection model in a wireless communication system aided by two rotatable IRSs. Specifically, we study the joint design of the base station transmit beamforming, as well as the cooperative passive beamforming and orientation of the two IRSs, to maximize the received signal-to-noise ratio (SNR). Under the light-of-sight (LoS) channels, we first develop a particle swarm optimization (PSO) based method to determine the IRS rotation and derive an optimal rotation in a closed-form expression for a two-dimensional IRS deployment. Then, we extend the design to the general Rician fading channels by proposing an efficient alternating optimization and PSO (AO-PSO) algorithm. Numerical results validate the substantial gains achieved by the IRS rotation over fixed-IRS schemes and also demonstrate the superior performance of the double rotatable IRSs over a single rotatable IRS given a sufficient total number of IRS elements.
format Preprint
id arxiv_https___arxiv_org_abs_2512_14037
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Cooperative Rotatable IRSs for Wireless Communications: Joint Beamforming and Orientation Optimization
Peng, Qiaoyan
Wu, Qingqing
Chen, Guangji
Chen, Wen
Shen, Shanpu
Ma, Shaodan
Signal Processing
Rotatable intelligent reflecting surfaces (IRSs) introduce a new degree of freedom (DoF) for shaping wireless propagation by adaptively adjusting the orientation of IRSs. This paper considers an angle-dependent reflection model in a wireless communication system aided by two rotatable IRSs. Specifically, we study the joint design of the base station transmit beamforming, as well as the cooperative passive beamforming and orientation of the two IRSs, to maximize the received signal-to-noise ratio (SNR). Under the light-of-sight (LoS) channels, we first develop a particle swarm optimization (PSO) based method to determine the IRS rotation and derive an optimal rotation in a closed-form expression for a two-dimensional IRS deployment. Then, we extend the design to the general Rician fading channels by proposing an efficient alternating optimization and PSO (AO-PSO) algorithm. Numerical results validate the substantial gains achieved by the IRS rotation over fixed-IRS schemes and also demonstrate the superior performance of the double rotatable IRSs over a single rotatable IRS given a sufficient total number of IRS elements.
title Cooperative Rotatable IRSs for Wireless Communications: Joint Beamforming and Orientation Optimization
topic Signal Processing
url https://arxiv.org/abs/2512.14037