Use of Rate Splitting in Multibeam Multicast NOMA Satellite Communication Systems

In this paper, we investigate the use of rate splitting to enhance the performance of multibeam multicast NOMA satellite communication systems. Rate splitting (RS) is employed to mitigate interbeam interference, and the NOMA technique is implemented in each beam to enhance spectrum efficiency. The combination of these two strategies increases the system's throughput flexibility. In addition, we derive a method for optimizing power allocation to maximize the sum-rate of the proposed scheme. This paper uses the quadratic transform method to transform the nonconvex optimization problem into a convex problem. The numerical results show that the proposed scheme outperforms the state-of-the-art systems.