REFLECTOR ANTENNA WITH COINCIDENT TRANSMIT-RECEIVE BEAMS PLUS CONICAL SCANNED RECEIVE BEAM

摘要

An antenna system includes a feedhorn (12) main reflector,(16) sub-reflector, and frequency selective member (24). The sub-reflector (20) includes an axially symmetrical reflecting surface (22) The frequency selective member(24) includes an axially non-symmetrical reflecting surface (22). The frequency selective member (24) transmits signals having a first frequency from the feedhorn (12) to the sub-reflector (20). These signals are symmetrically reflected by the sub­reflector (20) to the main reflector (16). The frequency selective member (24) reflects signals having a second frequency from the main reflector (16) to the feedhorn.(12) These signals are reflected at a small conical angle by the frequency selective member (24) to the feedhorn. (12) In this way, the present transmit/receive system provides coincident transmit and receive signals with only conically scanned receive signals.