Beam squint compensation technique for the Sardinia Radio Telescope

This paper analyses the beam squint compensation of the Sardinia Radio Telescope, when used for deep-space Telemetry, Tracking & Command. The proposed technique consists in the displacement of the lower beam-waveguide mirrors to separate the transmission and reception beams of the antenna. Two design approaches are discussed. The first is a bottom-up method, very accurate and straightforward but requiring many repeated and time-consuming analyses of the whole antenna. The second method is a top-down approach, based on the electromagnetic field matching on a fictitious planar grid defined along the beam-waveguide. This second method is much faster and it allows for implementing an automatic routine, based on an analytical formulation, to determine the best mirror movement for a given beam squint.