Partially Loaded Cavity Analysis by Using the 2-D FDTD Method

A compact two-dimensional(2-D)finite-difference time-domain(FDTD)method is proposed to calculate the resonant frequencies and quality factors of a partially loaded cavity that is uniform in the𝑧-direction and has an arbitrary cross section in the𝑥x–y𝑦plane.With the description of𝑧dependence by𝑘z,the three-dimensional(3-D)problem can be transformed into a 2-D problem.Therefore,less memory and CPU time are required as compared to the conventional 3-D FDTD method.Three representative examples,a half-loaded rectangular cavity,an inhomogeneous cylindrical cavity and a cubic cavity loaded with dielectric post,are presented to validate the utility and efficiency of the proposed method.