Feed array and beam forming network design for a reconfigurable satellite antenna

Describes the design considerations and component development for a feed array and beam forming network (BFN) associated with a multibeam reconfigurable antenna. Such antennas are being considered for future communications satellite systems to provide increased capacity and coverage flexibility. The antenna being developed to demonstrate this technology consists of a large offset reflector system and an active feed cluster of 128 horns, each with an associated amplifier, that generates 128 component beams of 0.45°x-3 dB beamwidths in the 12/14-GHz bands over a 4° x 8° x field of view for CONUS coverage. Eight reconfigurable shaped beams, each using the entire frequency band, are formed by the beam forming networks. The feed elements are dual mode conical horns providing good beam symmetry, low mutual coupling effects, and good cross-polarization properties (>30 dB)