A High-Efficiency Flat Plate Array for Direct Broadcast Satellite Applications

The design and performance of a low-cost, lightweight, high-efficiency flat plate array for receive-only satellite applications are described. The design is based on work performed at COMSAT Laboratories that has led to the development of novel printed-circuit radiators for both linearly polarized and circularly polarized applications. The radiating elements are excited via electromagnetic coupling to the feed lines, thus avoiding costly interconnections and resulting in a design that is highly amenable to low-cost mass production. The design is being implemented in a joint COMSA T/Matsushita Electric Works venture which has resulted in the production of commercial flat plate antennas that are presently available in Japan and will soon be introduced in Europe. The performance of these antennas is comparable to that of a parabolic antenna and exceeds that achieved by any competing commercially available flat antenna design.