Average Rate Maximization for Mobile STAR-RIS-Aided NOMA System
Peiyu Wang, Hong Wang, Yibo Fu
Abstract
Simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) has been regarded as a revolutionary technology for the sixth generation (6G) mobile networks. This letter investigates the transmission scheme for mobile STAR-RIS-assisted non-orthogonal multiple access (NOMA) system. Specifically, an uplink average rate maximization problem is solved by jointly optimizing the phase shifts, the channel assignment, and the STAR-RIS’s location for mobile STAR-RIS-aided NOMA system. Particularly, a channel assignment scheme is developed to enhance the performance of NOMA system with multiple users. Furthermore, a successive convex approximation (SCA) method is invoked to address the STAR-RIS location design subproblem and a semi-definite programming (SDP) method is leveraged to solve the phase shift optimization subproblem. Simulation results show that the proposed mobile STAR-RIS-empowered NOMA method achieves better average rate performance than various benchmarking schemes.