Optimal Beam Power Control for Co-Existing Multibeam GEO and LEO Satellite System

Abstract

With the development of satellite technology, the number of space satellites, especially low earth orbit (LEO) satellites, has increased dramatically. Due to the spectrum scarcity, sharing spectrum between different satellite systems is a promising option. This paper studies the cognitive satellite system with the co-existence of geostationary earth orbit (GEO) and LEO satellites. Based on the interference analysis, an adaptive beam power control problem is formulated that attempts to maximize the throughput of the LEO satellite users subject to the quality of service constraints of the GEO satellite users. The fractional programming technique is adopted to transform this nonconvex problem into a tractable form, which can be solved efficiently. Simulation results demonstrate that the proposed beam power control scheme can not only improve the spectrum efficiency of the co-existing satellite systems, but also ensure the user fairness.