Analysis of Axially Symmetrical Coaxial Discontinuity Structures by Using Two-Dimensional Nonuniform Finite-Difference Frequency Domain Method

By combining the main features of the 2D finite-difference time domain (FDTD) method and the traditional finite-difference frequency domain (FDFD) method, a 2D FDFD method with nonuniform grids and perfectly matched layers (PML) is presented in this paper to analyze axially symmetrical coaxial discontinuity structures. Numerical results show that the 2D FDFD method is much more efficient than the commonly used 2D FDTD method in solving the frequency response of the structures. High accuracy of the 2D FDFD method is shown in a simple numerical example which can be solved by using the mode matching method.