Robust Transceiver Design for RIS-Aided mmWave Systems Under Hardware Impairments and CSI Uncertainty

Abstract

This letter investigates robust transceiver design for reconfigurable intelligent surface (RIS)-assisted millimeter-wave multiuser multiple-input single-output (MU-MISO) systems. We explicitly consider practical hardware impairments, including phase errors and phase-dependent amplitude response, alongside channel state information (CSI) uncertainty. A joint optimization algorithm based on alternating optimization is proposed to design the transmit precoder, receiving equalizer, and discrete RIS phase shifts. The objective is to minimize the worst-case mean square error (MSE). Simulation results demonstrate that the proposed scheme significantly enhances system robustness and outperforms existing benchmarks under realistic hardware constraints.