A dual-band equal-beam reflector multiple beam antenna for satellite communications

A dual-band multiple beam antenna (MBA) system that is suitable for satellite communications at K/Ka-band frequencies is introduced in this paper. This antenna system employs a minimum number of reflectors, just half of conventional multiple beam antennas, because it uses a dual-band feed horn. It is shown that the antenna system can provide higher edge-of-coverage (EOC) gain and higher co-polar isolation (C/I) among beams that re-use the same frequency channels by using feed horns with high efficiency. Reflectors in this antenna system are illuminated by the mainlobe of the downlink feed single at lower frequency, while the mainlobe and first sidelobe of the uplink feed single illuminate reflectors at higher frequency so that the uplink and downlink antenna singles can cover the same cell size on the Earth.