Hemispherical dielectric resonator antenna with a concentric conductor

A hemispherical dielectric resonator antenna with a concentric conductor is studied theoretically. The new configuration offers a wider bandwidth and a higher resonant frequency than that without the conductor. The exact electric field Green's function due to the probe current is presented, and the moment method is used to solve the probe current from which the broadside TE/sub 111/ mode VSWR is determined. The effects of the probe displacement and of the probe length on the VSWR are discussed.