Power Allocation and Beamforming Design for Uplink Rate-Splitting Multiple Access with User Cooperation

We consider a two-user uplink cooperative rate-splitting multiple access (C-RSMA) and seek to maximize the minimum signal-to-interference-plus-noise ratio (SINR) by jointly optimizing the beamforming at the base station (BS) and device transmit power. Due to the high coupling among the variables, the problem is non-convex and difficult to solve directly. To handle this challenge, we utilize successive convex approximation (SCA) and difference of convex (DC) based approach to approximate the non-convex problem to a convex one. The simulation results demonstrate that our proposed scheme can outperform cooperative non-orthogonal multiple access (C-NOMA) and other baseline schemes.