The efficient analysis of cylindrical resonators using a modified FDTD method

The author describes a method of efficiently and accurately treating cylindrical metal structures whose feature sizes are similar to or smaller than the unit cell size of the FDTD mesh and he has demonstrated the accuracy obtainable for the particular example of a centre fed dipole. It is possible to apply the same technique to dielectric boundaries or to metal edges and corners by choosing suitable functions for the asymptotic field variation. Thus a single unified algorithm can be applied to a wide variety of geometric details. The application of this technique to a complex structure involving wires, narrow slots, and dielectric boundaries is presented