Abstract:

The adjustment of the reflector antenna feed position and orientation depends on engineering experience, adjustment quantities are calculated from far field in this paper. Based on aperture field method, the influence relationship between feed errors and far field is expanded into firstorder Taylor series, resulting that explicit sensitiveness expressions of far field to feed errors are established. Then feed errors and far field are linked with overdetermined linear equations, and feed adjustment quantities can be approximatively calculated based on singular value decomposition method with the help of measured far field. For a 4 m reflector antenna, the applicable scope of the proposed method is discussed, and simulation cases show that the electrical performance can be effectively improved after adjusting the feed. The proposed method provides the theoretical guidance for the feed installation and adjustment.