Unique reflector arrangement with very wide field of view for multibeam antennas

We minimise the aberrations arising in a double reflector antenna when the feed is displaced from the focus. In a previous article, astigmatism and primary coma were reduced by slightly deforming the two reflecting surfaces and optimising the principal ray angles of incidence. Here we further reduce aberrations by determining the optimum subreflector magnification. The result is a new reflector arrangement, consisting of a deformed paraboloid combined with a deformed hyperboloid, having the widest possible field of view obtainable with two reflectors in a compact arrangement of short focal length.