Total-Field versus Scattered-Field Finite-Difference Codes: A Comparative Assessment

This paper deals with time-domain finite-difference (TDFD) techniques for solutions of Maxwell´s equations. Two types of algorithms are treated: scattered-field algorithms in which the incident fields (E¿i,H¿i), are analytically known but the scattered fields (E¿s,H¿s) must be computed with TDFD methods, and total-field calculations in which total fields (E¿T,H¿T) are found by TDFD techniques. Nonlinear problems and heavily shielded cavities can only be treated with the total-field approach. The price of this generality is an increase in mathematical complexity and computational cost.