Research on Robust Beamforming Algorithm in Dual Satellite Communication System

To solve the problem of interference existing in the frequency sharing between the Geostationary Earth Orbit (GEO) satellite system and the Low Earth Orbit (LEO) satellite system，this paper reconsidered the use strategy of spatial spectrum resources, proposed a robust adaptive beamforming algorithm based on low-orbit distributed satellite cluster from point view of power isolation in the spatial domian. The proposed beamforming algorithm comprehensively consider the robust constraint design for the certain error in the array steering vector caused by the long propagation delay of the satellite communication system based on linearly constrained minimum variance (LCMV) criterion. A nonconvex beamforming optimization problem was relaxed to a second-order cone constraints (SOCP) problem. Thus, the beamformer weight vector was obtained by the Taylor series approximation method. Simulation results show that the proposed robust beamforming algorithm is more adaptable in the satellite communication environment, and can effectively alleviate the problem of co-frequency interference caused by frequency sharing of dual-satellite communication systems.