FDTD Analysis of a Probe-Fed Dielectric Resonator Antenna in Rectangular Waveguide

Abstract — Dielectric resonator antennas (DRA) are charac-terized for operation in a guided-wave environment with the ultimate goal of their use in modeling of waveguide-based DRA amplifier arrays for spatial power combining. Performance of a single probe-fed DRA element in rectangular waveguide is analyzed by varying design parameters of the DRA and the feeding probe to optimize the structure for the scattering char-acteristics (port matching and coupling). The effect of hard walls on the DRA behavior is also studied. The numerical analysis of waveguide-based DRA elements is based on the Finite-Difference Time-Domain (FDTD) method and a coaxial probe is modeled by a thin wire approximation implemented in the FDTD algorithm. The numerical results are compared with those generated by using commercial software and exhibit a very good agreement. Index Terms — Dielectric resonator antenna, rectangular waveguide, hard wall, Finite-Difference Time-Domain method. I