Radiation characteristics of cylindrical dielectric resonator antennas

The radiation patterns of cylindrical dielectric resonator antennas excited with a TM/sub 11/ mode are computed numerically using the method of moments. The numerical data obtained are in good agreement with available experimental results. The effect of the ground plane size, dielectric constant, and resonator dimensions on the radiation patterns are investigated. It is found that the symmetry of the radiation patterns is improved by reducing the grounds plane dimensions, while the backlobe level is reduced by placing the antenna in a topless cylindrical cavity. Further improvement is obtained by surrounding the cylinder by a quarter-wavelength choke.<
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