Radiation fields of the short-backfire antenna

A method for the approximate calculation of the radiation fields of a short-backfire antenna is presented. This technique is based upon the assumption that the aperture field is distributed approximately cosinusoidally in both horizontal and vertical planes as evidenced by near-zone field measurements. It appears that the short-backfire antenna is essentially a circular aperture antenna with cosinusoidal aperture field, and that the dipole functions merely as an exciter for this field.