Overlapped Feeds in Multi Beam Reflector Antennas

The performances of focal plane arrays that implement multi- beam coverage from a single reflector antenna are usually reduced by conflicting requirements on the feed elements. Dense packing is required to minimize the beam separation, while typically large apertures provide the high feed directivity which in turn translates in low spill over losses from the reflector. In this contribution, the use of a dielectric super-layer to shape the radiation pattern of each feed, so that the spill over from the reflector is reduced without increasing the dimensions of each aperture, is discussed.