Computation of cross-polarization radiated by an elliptical feed horn

Elliptical waveguides and horns find various applications, such as feeds for shaped reflector antennas [1–6], in microwave resonator [7], filter [8], polarizer [9], etc. As a radiating feed, the elliptical waveguide/horn can generate different beamwidths in two-orthogonal planes. Such feeds are preferred for space-borne reflector antennas to obtain an elliptical footprint on earth [4]. Generally, for radar, remote sensing as well as for satellite applications it is preferred that the overall cross-polarization in the secondary radiation pattern should be as small as possible. As, one of the sources of overall cross-polarization is the cross-polarization of the feed that illuminates the reflector antenna, it is worthwhile to first estimate the cross-polarization of the primary feed. In this context, the present paper is focused on the computation of cross-polarization radiated by an elliptical waveguide and the elliptical horn.