ANALYSIS OF GENERAL 3-D PEC STRUCTURES USING IMPROVED CPFDTD ALGORITHM

The contour path finite difference time domain (CPFDTD) method, employ ing locally distorted integration contours, has been shown to give acc urate results for curved three-dimensional metal structures. The numer ical stability of this scheme is not, however, guaranteed and signific ant skill is required to generate an appropriate grid. The authors pre sent a modification to the three-dimensional CPFDTD method Which ensur es stability and which permits simple generation of the locally distor ted grid. The accuracy of the scheme is demonstrated through the calcu lation of the resonant frequencies of circular cylindrical and spheric al resonators.