Surface Distortion Compensation in Reflector Antennas Using a Shaped Sub-Reflector

Surface distortions on the main reflector change the radiation pattern of the reflector antenna and degrade their radiation characteristics. There are different methods to compensate the undesired effects of the main reflector’s surface distortion. in the present study, it has been shown that by using a shaped sub-reflector, one can compensate the effects of the main reflector’s distortions. Based on the variational mathematics, the radiation pattern has been linearized and reformulated in the matrix form. The reverse problem has been solved using the Singular Value Decomposition (SVD), and it is shown that for a dual-reflector antenna, the proposed method can be used to design a compensator shaped sub-reflector. Results show that if the amplitude of the distortion on the main reflector is less than quarter wavelength, the proposed algorithm can converge to the solution very fast.