Common aperture satellite antenna system for multiple contoured beams and multiple spot beams

This paper presents a novel satellite antenna that generates simultaneously multiple contoured beams at Ku-band and multiple spot beams at Ka-band using a common aperture reflector antenna. It employs a shaped reflector that optimizes the RF performance of the desired Ku-band contoured beams on the ground by employing multiple corrugated horns that are located along the focal-plane of the reflector. The synthesized reflector surface at Ku-band is employed to generate the Ka-band spot beams by "un-folding" the large quadratic phase distribution using an optimized location for the Ka feeds that is far from the focal-plane and by placing the feeds on a spherical arc. The common aperture antenna replaces three or more large reflectors on the spacecraft and provides significant cost and mass reductions for future communications satellites.