Parametric study of shaped Cassegrain antennas

The effect on gain and the first few sidelobes of Cassegrain antennas due to axial feed and subreflector shifts is investigated. The shaped and classical Cassegrain designs are the objects of study, and the motivation is the concern over possible compromise introduced by the maximum G/Ta design philosophy on a radio telescope antenna. The result of the investigation is a set of general design rules for shaped Cassegrain antennas, based on the examples studied.