Transmit-Receive L/S-Band Feed Chain for Array-Fed Unfurlable Reflector Antennas

This work describes part of the activities carried out in Thales Alenia Space Italy and Space Engineering for the development of RF chains to be employed in the next generation L/S band multi-beam antennas. More specifically, we are targeting the kind of antennas which are used in the frame of the Mobile Satellite Services (MSS) and are required to generate a cellular coverage. The MSS antennas can be characterized by a relatively low number of contoured beams, as it happens in the S-DMB applications and/or by a relatively high number of beams occurring in L/S band for point to point services. For what concerns the design of the feed system, the two antenna family lead to different requirements and to different solutions. In our work, we have studied a radiating element suitable for both type of antennas, adaptable to waveguide or coax interface and interfaced to a coax interdigital diplexer compatible to the limited radiating element envelope.