Study of high-efficiency corrugated hard-horn antennas using classical approaches: Hard circular waveguide mode, phase factor, and aperture integration

In this paper, a classical-type approach is used to analyze the hard horn antenna. The quasi-TEM mode in the longitudinally corrugated cylindrical waveguide is found by using the homogenized asymptotic boundary conditions. The finite horn length is accounted for by including a phase factor in the waveguide-aperture fields, and the radiation patterns are finally obtained by aperture integration. The bandwidth is found to be much wider than previously anticipated with respect to low cross-polarization. Also, an advanced mode-matching code has been used for verification of the aperture field and the radiation patterns obtained with the much faster classical model