A feed system for a multibeam antenna at 20/30 GHz

A Feed System is presented capable of handling two indipendent Communication Channels at 20 GHz and One RF Sensing Signal at 27 GHz. The trade off results for the feed at 20 GHz show that a smoothed wall conical horn with shaped profile operating on the TE_{11} mode is the best compromise between electrical performance and mechanical constraints. A special OMT is described which allows the introduction of the RF Sensing signal at 27 GHz without the excitation of spurious modes. Furthermore the RF Sensing port present enough directivity to minimize power loss.