The Finite-Difference Time-Domain Method (FDTD)
Application of the Finite-Difference Time-Domain (FDTD) technique to simulate electromagnetic phenomena was first reported by K. S. Yee in 1966. As in many of the techniques the FDTD technique starts with a discretization of the equations that model the phenomena. In this case, a pair of differential equations (Maxwell or Telegrapher) are converted to a group of difference equations that are solved for staggered time and space intervals. This mathematical discretization conveys a physical segmentation of the structure on study. The segmentation can be performed using cells of equal and different sizes, in different directions, and of regular and arbitrary shapes. At present, people working with FDTD follow two general ways. Some persons work with the curl Maxwell equations and the absorbing boundary conditions to solve radiation, propagation, and scattering problems using a full wave model. Other persons work with the telegrapher equations and circuital boundaries to solve circuit and power transmission problems in one and two dimensions.