High-Efficiency Square-Aperture Horn Antenna with a Linear Spline Profile

The geometrical efficiency within an array cell of a square-aperture horn is supposed to be higher compared to a circular horn resulting in its suitability for array applications. In this article, the electromagnetic characterization of an HFSS-simulated horn antenna design is presented. The present work demonstrates a square-aperture horn antenna incorporated inside a rectangular parallelepiped metallic structure. The proposed horn consists of a rectangular waveguide segment, a linearly spline-profiled section, and a square aperture-with a loaded polyethylene dielectric lens-directed to free space. At 10 GHz, aperture efficiency is improved to 95.4% and the design produces nearly equal 3 dB and 10 dB beamwidth patterns in both H- and E-planes. The generation of higher order mode coefficients was analyzed while VSWR and radiation pattern were also simulated across the X-band.