Very short and efficient feeder design from monomode waveguide

Abstract

In this paper, we present an original and short corrugated horn antenna profile to obtain the HE11 corrugated circular waveguide mode exciting with a pure TE11 monomode smooth circular waveguide mode. We will obtain a far field pattern with a very low crosspolarization, high symmetry and very low sidelobes in a wide frequency band. The proposed corrugated antenna has a longitudinal section composed of two hyperbolic profiles in series, one concave and the other convex united at a point, such that the derivative is continuous. Superimposed there is an additional tapering of the corrugation depth that goes from λ/2 at taper input to λ/4 within the first hyperbola. This original synthesis procedure has been successfully tested by computational simulation. The calculation method has been validated with experimental results of other authors.