Optimization Procedure for Wideband Matched Feed Design

The inherently high cross polarization of prime focus offset reflector antennas can be compensated by launching higher order modes in the feed horn. Traditionally, the bandwidth of such systems is in the order of a few percent. We present a novel design procedure where the entire matched feed and reflector system can be efficiently optimized. This allows the design parameters of the matched feed to be directly related to the desired design goals in the secondary pattern over a specified band. Using this procedure, we present a design of a die-castable axially corrugated matched feed horn that provides an XPD improvement better than 7 dB over a 12% bandwidth for a reflector with an f/D of 0.5. An investigation of the mode requirement for an arbitrary circular aperture feed is also presented.

Publication: Proc. EuCAP’2016, 10th European Conference on Antennas and Propagation
Place: Davos, Switzerland, 10-15 April 2016