Modal considerations for synthesizing the tapering profile of a quadruple-ridged flared horn antenna

A technique is proposed to synthesize the ridge taper of a quadruple-ridged flared horn (QRFH) antenna. By considering the modal propagation in the horn it is possible to improve the antenna performance. A QRFH is designed for an offset Gregorian reflector system and produces an aperture efficiency above 50% across the entire operational bandwidth (6∶1).