Repeaters for multibeam satellites

摘要

A repeater for a multibeam communications satellite combines the features of coaxial channel interbeam switching and subchannelization of some of the channels. In one embodiment described, the input radio-frequency signals from the input beams are fed through the input multiplexers to form channels. Some, but not all, channels are subsequently subchannelized for interbeam switching. In another embodiment of the invention, a portion of the incoming radio frequency signals bypasses the input demultiplexer and is filtered for noise-limiting reasons, converted down to an intermediate frequency and then subchannelized using SAW filters. The specification also teaches that digital techniques can be used to obtain the same results. Especially in the case of satellites with a large number of beams and a large number of channels, it is not necessary to have full interbeam switching of all the subchannels derived from one channel: instead, the specification proposes the use of parallel configurations of smaller, less complex switching networks.