FDTD analysis of a probe-fed dielectric resonator antenna in rectangular waveguide

A probe-fed dielectric resonator antenna (DRA) element is investigated for operation in a waveguide environment with application to spatial power combining amplifier arrays. The method of analysis is based on the finite-difference time-domain (FDTD) approach, wherein a rectangular waveguide and DRA are discretized by using a traditional Yee cell griding and a coaxial line is modeled by a thin wire approximation. The input impedance and scattering parameters are studied by varying geometrical and material parameters of the DRA and the coaxial probe feed. The numerical results obtained by the proposed FDTD method are compared with those generated by using a commercial software and exhibit very good agreement.