Energy-Efficient RSMA for Multigroup Multicast and Multibeam Satellite Communications

This letter studies energy-efficient rate-splitting multiple access (RSMA) for multigroup multicast and multibeam satellite communication systems. Specifically, we minimize the unmet system capacity, which means the rate difference between the requested user rate and the effective achieved rate, and communication energy consumption by optimizing the power allocation and rate allocation under the per-feed power and sum radiated power constraints. To solve the non-convex optimization problem, auxiliary variables and epigraph method are introduced to transform the original problem into a difference of convex functions programming. Then, the successive convex approximation (SCA) technique is used to obtain a suboptimal solution. Numerical results verify the superiority of our proposed solution compared to the benchmark methods.