Scanning phased array antenna system

摘要

The present invention relates to a phased array antenna system which transmits a local oscillator signal in a scanable spotbeam from a first array of feed elements (12l-12m) via a reflector or lens (16) and a frequency diplexing means (18) to a second array of feed elements (20l-20n) disposed on the image plane of the first array of feed elements. A message signal in a second beam also impinging the frequency diplexing means from a separate direction is also received at the second array of feed elements. The message signal and the local oscillator signal concurrently received at each of the feed elements of the second array are mixed in individual mixers and the output of each mixer can be reradiated for transmission to a remote receiver or combined with the outputs of the other mixers for use by a local receiver. A feed element for use in an antenna for mixing a local oscillator and RF signal to produce an IF or baseband signal, or vice versa, using a stripline arrangement is also disclosed.