Analysis of dielectric resonator antennas using characteristic modes

The characteristic mode (CM) theory has been widely used for solving the resonant behaviors of radiation problems, since it can get the resonance frequency and orthogonal modal field. However, most previous works focus on the perfect conducting bodies. Now we propose a systematic method to analyze the dielectric resonator antennas (DRA) by using CM theory. The calculation of the CMs bases on the PMCHWT formulation. Moreover, the feeding location is optimized by studying the modal field distribution inside the dielectrics. A DRA with multiple dielectrics is analyzed in this paper. Numerical results present a good agreement with HFSS simulations. It validates the accuracy of the proposed method to analyze the radiating properties of DRA.