STAR-RIS-aided RSMA for the URLLC multi-user MIMO Downlink

TL;DR

This paper explores the integration of STAR-RIS with RSMA to improve energy efficiency in multi-user MIMO downlink systems, demonstrating significant gains through joint optimization.

Contribution

It introduces a joint optimization algorithm for STAR-RIS and RSMA in FBL MIMO systems, highlighting the synergy and energy efficiency improvements over existing methods.

Findings

STAR-RIS achieves full-plane coverage.

RSMA effectively manages interference.

Significant energy efficiency gains over traditional methods.

Abstract

Rate splitting multiple access (RSMA) is intrinsically amalgamated with simultaneously transmitting and reflecting (STAR) reconfigurable intelligent surfaces (RIS) to enhance energy efficiency (EE) of the finite block length (FBL) multiple-input multiple-output (MIMO) downlink. An alternating optimization-based algorithm is proposed to jointly optimize the transmit beamforming matrices, STAR-RIS configurations, and rate-splitting parameters. STAR-RIS attains 360-degree full-plane coverage, while RSMA provides a prominent gain by efficiently managing interference. Numerical results reveal a strong synergy between RSMA and STAR-RIS, demonstreating significant EE gains over reflective RIS and spatial division multiple access (SDMA).