The radiation of spherical sector horns with walls of differing impedance

The implementation of an antenna system with given radiation characteristics requires frequently the development of horn-type radiators with directional diagrams which satisfy special requirements. An investigation is conducted of spherical sector horns with walls having certain surface impedance characteristics. For small angles of aperture, the spherical sector horn represents a good approximation for the pyramidal horn which is mainly used in practical applications. The radiation field is computed with the aid of the aperture field method. It is assumed that only the main carrier wave is excited. The admissibility of this assumption has been verified with the aid of experimental data. The transversal field distribution is determined by means of a finite difference procedure.