ABSTRACT
FDTD as developed here solves the Maxwell curl equations for the scattered E and H fields using a broadband analytically described transient incident E and H waveform. The numerical solutions are based on the leapfrog technique. There are many alternate formulations of FDTD to this approach. We feel none are superior in general and most, if not all, have some weakness. It is nonetheless important to survey these alternate formulations so as to provide an appreciation of the possibilities and perhaps to discover a particularly apt approach to a particular problem.
