A novel approach to enhance the bandwidth of miniaturized dielectric resonator antennas

The paper presents the concept and implementation of a wideband, high-gain miniaturized dielectric resonator antenna (DRA). A dual-resonance characteristic is achieved by merging the resonances of an aperture antenna and a DRA; miniaturization is provided by the high dielectric constant of the resonator. The design enhances the bandwidth of the constituent antennas without compromising their efficiency and radiation characteristics. In addition, the design enforces low cross-polarization levels as well its a unique polarization direction over the entire bandwidth. It is shown that, with proper design, the two resonances inherent in all DRA designs with resonant feed structures can be merged for bandwidth optimization. In addition, the similarity of the aperture and DRA radiation characteristics allows preservation of the radiation patterns and polarization over the entire bandwidth. The design parameters are summarized and simulation results given. A 0.2λ₀ antenna exhibiting over 25% bandwidth and gain exceeding 4 dBi has been built and characterized.