Joint Receive Antenna Selection and Beamforming in RIS-Aided MIMO Systems

TL;DR

This paper proposes a low-complexity joint design for RIS-assisted MIMO systems, optimizing antenna selection, precoding, and RIS phase-shifts to maximize uplink sum-rate with an efficient iterative algorithm.

Contribution

It introduces a novel joint optimization framework for antenna selection, precoding, and RIS phase-shifts in RIS-aided MIMO systems, using a tractable iterative algorithm.

Findings

The proposed algorithm effectively approximates the optimal design.

Numerical results show superior performance over benchmarks.

The method reduces computational complexity for large systems.

Abstract

This work studies a low-complexity design for reconfigurable intelligent surface (RIS)-aided multiuser multiple-input multiple-output systems. The base station (BS) applies receive antenna selection to connect a subset of its antennas to the available radio frequency chains. For this setting, the BS switching network, uplink precoders, and RIS phase-shifts are jointly designed, such that the uplink sum-rate is maximized. The principle design problem reduces to an NP-hard mixed-integer optimization. We hence invoke the weighted minimum mean squared error technique and the penalty dual decomposition method to develop a tractable iterative algorithm that approximates the optimal design effectively. Our numerical investigations verify the efficiency of the proposed algorithm and its superior performance as compared with the benchmark.