Research on interference avoidance technology for low Earth orbit satellite based on spatial processing

Abstract

With the rapid development of low earth orbit (LEO) satellite systems, the interference between LEO satellite constellations using the same frequency has become increasingly prominent. Because of the large number and high dynamic characteristic of LEO systems, the traditional interference avoidance methods have great limitations. Based on existing interference avoidance methods, this paper establishes a mathematical model of the interference avoidance for LEO satellite systems, and proposes an interference avoidance method using spatial processing. Aiming at the fatal main lobe interference avoidance problem, the method turns main lobe interference into side lobe interference by switching the beam of earth station to other satellites within the visual range. Then it uses adaptive beamforming method of side lobe null broadening to suppress side lobe interference in high dynamic environment. The interference scenario between OneWeb and Starlink constellations is used for simulation. The results turn out that the proposed method can effectively reduce the interference between LEO constellations and improve the link quality.