Performance of RIS-Assisted Alamouti STBC-NOMA Network

Abstract

This study considers a non-orthogonal multiple access system, where the base station (BS) with Alamouti space-time block coding communicates with multiple users (L) with the help of a reconfigurable intelligent surface (RIS). In the system, the RIS elements are divided into L groups, each group serves one user and aligns the phases of the incoming signals consistently. The expression of outage probability for the users is defined using the statistical properties of the signal-to-interference+noise ratio (SINR) of the reflection channel from the BS to the users via the RIS. The numerical results are presented with Monte Carlo simulations for Rayleigh fading channel. © 2025 Elsevier B.V., All rights reserved.