Low-Profile Radially Corrugated Horn Antenna

Abstract

[EN] This letter proposes a low-profile horn antenna with radial corrugations. The depth and width of the corrugations are suitably chosen to excite the mode HE11 in the corrugated section. This mode spreads uniformly across the whole aperture, thereby maximizing the radiating area and the aperture efficiency. The good polarization purity of mode HE11 provides a good cross-polar level and a low sidelobe level. The structure is fed by a circular waveguide with two matching elements on the feeding plane that minimize the return loss level. A prototype has been fabricated and measured to operate in the Ku band. The prototype, with a height of just 6.9 mm, i.e., 0.3 lambda0, provides a maximum gain above 12.2 dBi and an aperture efficiency better than 72% within the operating frequency band.