Improvement of contoured beam characteristics of a parabolic reflector antenna by asymmetrically distributed array feed

Precise contoured beam is important especially in broadcasting satellite application. In order to achieve a precise contoured beam for Malaysia, selection of feed structures is very important. In this paper, feed structures for horn antenna and array antenna are studied for a parabolic reflector antenna system. Feed positions of the feed structures are determined by a newly developed feed position graph. For the case of a horn feed, a problem with regards to its physical dimension is shown. By employing array feed, precise contoured beams are achieved. The actual performance and accuracy of contoured beams are ensured through electromagnetic simulations in FEKO.