RSMA for Reconfigurable Holographic Surface-aided Downlink Near-Field Communication

This work integrates rate-splitting multiple access (RSMA) in a reconfigurable intelligent surface (RIS)-aided holographic multi-input-multi-output (MIMO) downlink wireless communication system under near-field coverage. To maximize the sum rate of the system, we jointly optimize the transmit beamforming at the Base station (BS) and passive beamforming at the RIS. We suggest an iterative solution based on alternating optimization (AO) that efficiently solves the joint optimization problem utilizing analytical tools such as the successive convex approximation. Finally, the numerical results are shown to confirm the proposed algorithm’s convergence and efficacy. Furthermore, We also highlight the impact of reflecting elements, minimum rate constraint, maximum transmit power at the BS, and number of downlink users. The dominance of RSMA over conventional multiple-access technologies such as non-orthogonal multiple access (NOMA) is also demonstrated.