Practical comparison of finite difference time domain schemes

Practical finite-difference methods for the time-domain Maxwell´s equations are considered. Leap frog, Lax-Wendroff, and upwind schemes are considered. As the basis of this analysis, Maxwell´s equations are expressed as a system of conservation laws. Practical considerations, such as computational efficiency and memory requirements, for the methods are discussed. The example of the penetration of electromagnetic energy through a shield with a thick gap in two dimensions is used to compare the methods. It is shown that the time per node is relatively constant for each method, but is considerably greater for the upwind scheme. It is also shown that the upwind algorithm resolves discontinuities in the medium better than the other techniques.<>