Beam forming network for multiple-beam-feed sharing antenna system

Abstract

A multiple beam antenna system (10) for use in satellite communications. The system (10) includes a feed array (20) containing multiple feed elements (22) which operate in connection with communications beams. In a transmitter application, the feed elements (22) are driven by feed signals delivered thereto from a beam forming network (14). The beam forming network includes multiple beam ports (16) which receive as inputs composite beam signals. The beam forming network includes feed ports (18) as outputs which deliver feed signals to the feed array (20). The beam forming network (14) includes a divider circuit trace (48) and a combiner circuit trace (46) aligned along substantially parallel planes. Combiners (111-117) within the combiner circuit trace (46) are arranged in clusters (92), such that each combiner (111-117) within a cluster (92) operates in conjunction with a common feed signal. The dividers (121-127) are similarly grouped in clusters (94), such that each divider (121-127) within a cluster (94) operates in conjunction with a common composite beam signal. The combiner and divider clusters (92, 94) are arranged with respect to one another to simplify and minimize the length of interconnections (60) therebetween.