Rate Splitting Multiple Access for Next Generation Cognitive Radio Enabled LEO Satellite Networks

TL;DR

This paper introduces a novel RSMA-based resource allocation scheme for cognitive radio-enabled LEO satellite networks, optimizing sum rate while managing interference with GEO satellites.

Contribution

It presents an innovative three-step optimization framework combining convex approximation, KKT conditions, and greedy algorithms for resource management in LEO SatCom.

Findings

Significant sum rate improvement over benchmark schemes

Effective interference management with GEO SatCom

Demonstrated efficiency of the proposed optimization approach

Abstract

This paper proposes a cognitive radio enabled LEO SatCom using RSMA radio access technique with the coexistence of GEO SatCom network. In particular, this work aims to maximize the sum rate of LEO SatCom by simultaneously optimizing the power budget over different beams, RSMA power allocation for users over each beam, and subcarrier user assignment while restricting the interference temperature to GEO SatCom. The problem of sum rate maximization is formulated as non-convex, where the global optimal solution is challenging to obtain. Thus, an efficient solution can be obtained in three steps: first we employ a successive convex approximation technique to reduce the complexity and make the problem more tractable. Second, for any given resource block user assignment, we adopt KKT conditions to calculate the transmit power over different beams and RSMA power allocation of users over each beam. Third, using the allocated power, we design an efficient algorithm based on the greedy approach for resource block user assignment. Numerical results demonstrate the benefits of the proposed optimization scheme compared to the benchmark schemes.