A combination of linear and slot antennas for quasi-isotropic coverage

The combination of a linear antenna and slot antenna can be used to provide a relatively isotropic radiation pattern when the dipole is perpendicular to the plane of the slot. The theoretical far-field radiation pattern of a dipole flanked by a two-element array of slot antennas is formulated. The fields for two different phasings between the elements of the combination antenna are calculated and the degree of approximation to an isotropic source in the sense of the total field noted. An experimental antenna was fabricated and the radiated fields measured with good agreement found with the theoretical formulas.