We study the performance of a phase-noise impaired double reconfigurable intelligent surface (RIS)-aided multiuser (MU) multiple-input single-output (MISO) system under spatial correlation at both RISs and base-station (BS). The downlink achievable rate is derived in closed-form under maximum ratio transmission (MRT) precoding. In addition, we obtain the optimal phase-shift design at both RISs in closed-form for the considered channel and phase-noise models. Numerical results validate the analytical expressions, and highlight the effects of different system parameters on the achievable rate. Our analysis shows that phase-noise can severely degrade the performance when users do not have direct links to both RISs, and can only be served via the double-reflection link. Also, we show that high spatial correlation at RISs is essential for high achievable rates.
@article{arxiv.2201.12129,
title = {Impact of Phase-Noise and Spatial Correlation on Double-RIS-Assisted Multiuser MISO Networks},
author = {Zaid Abdullah and Anastasios Papazafeiropoulos and Steven Kisseleff and Symeon Chatzinotas and Bjorn Ottersten},
journal= {arXiv preprint arXiv:2201.12129},
year = {2022}
}