An interactive demonstration of electromagnetic wave propagation using time-domain finite differences

The finite difference time-domain (FDTD) method is one of the most widely used computational methods in electromagnetics. Using FDTF, Maxwell´s equations are solved directly in the time domain via finite differences and time stepping. the basic approach is relatively easy to understand and is an alternative to the more usual frequency-domain approaches. In order to take advantage of this, an interactive personal computer program based on FDTD has been developed. The program directly solves Maxwell´s equation via finite differences. The solution is for one dimension, corresponding to normal incidence propagation through a planar stratified medium. The program displays an electromagnetic pulse as it propagates through the medium. Since Maxwell´s equations are solved directly, the reflected and transmitted pulse amplitudes demonstrate how the reflection and transmission coefficients determine reflected and transmitted wave amplitudes. Since lossy material layers can be included, frequency dispersion can be demonstrated