Energy- and spectral-efficient power allocation in multi-beam satellites system with co-channel interference

Multi-beam broadband satellite communication can afford high throughput demands and flexible deployments with large coverage area, except for their scarce and expensive onboard resources. By introducing a shadowed-Rice (SR) fading model in this paper, a power allocation scheme is proposed for energy efficiency (EE) and spectrum efficiency (SE) trade-off in the multi-beam satellite system with co-channel interference. To meet different traffic demand among various spot beams, signal-to-interference-ratio (SIR) is first derived according to the statistic characteristic of the forward link and the analytical result of the achievable rate is approximately obtained in a closed-form expression. Then, the inter-beam power allocation problem is formulated as a multi-objective optimization problem under constraints of individual throughput and total power consumption. A multi-objective metaheuristic technique, namely non-dominated sorting in genetic algorithms (NSGA-II), is adopted to solve this optimization problem and obtain applicable Pareto front. Simulation results demonstrate the validity of the closed-form expression and the efficiency of the NSGA-II algorithm.