Design of dual-mode conical horn feed with equal E and H patterns

This paper presents a high power feed system for 7.3 m Cassegrain antenna. In order to make E and H patterns of the feed equal in the illuminated area, the dual-mode conical horn is chosen as the feed form. Since the high power signal is transmitted from the BJ-32 waveguide, a mode convertor from rectangular TE10 mode to circular TE11 mode in the feed system should be provided. The feed system, including a dual-mode conical horn and a mode convertor, was designed, manufactured, and measured. The measured results indicate that the feed system achieves the design goal, and the measured results agree well with the theoretical results.