Use of static field solutions in the FDTD method for the efficient treatment of curved metal surfaces

The treatment of surfaces which are curved or which are not parallel to the co-ordinate axes using the finite difference time domain (FDTD) method is notoriously problematic. The Letter describes a technique which is general, comparatively simple and requires negligible computational overhead. Results are given for the example of a circular cylindrical cavity resonator which show good agreement with analytical formulas.