Perfect channel state information (CSI) is challenging to obtain due to the limited signal processing capability at the intelligent reflection surface (IRS). In this paper, we study the worst-case robust beamforming design for an IRS-aided multiuser multiple-input single-output (MU-MISO) system under the assumption of imperfect CSI. We aim for minimizing the transmit power while ensuring that the achievable rate of each user meets the quality of service (QoS) requirement for all possible channel error realizations. With unit-modulus and rate constraints, this problem is non-convex. The imperfect CSI further increases the difficulty of solving this problem. By using approximation and transformation techniques, we convert this problem into a squence of semidefinite programming (SDP) subproblems that can be efficiently solved. Numerical results show that the proposed robust beamforming design can guarantee the required QoS targets for all the users.
@article{arxiv.1911.06237,
title = {Robust Beamforming Design for Intelligent Reflecting Surface Aided MISO Communication Systems},
author = {Gui Zhou and Cunhua Pan and Hong Ren and Kezhi Wang and Marco Di Renzo and Arumugam Nallanathan},
journal= {arXiv preprint arXiv:1911.06237},
year = {2020}
}
Comments
This paper has been accepted in IEEE Wireless Communication Letter. This paper is the first to study the robust transmission design for IRS-aided MISO system as the CSI is challenging to obtain, and thus CSI is generally imperfect