A method for incorporating different sized cells into the finite-difference time-domain analysis technique

A method is presented that simplifies the process of incorporating a refined mesh around a discontinuity in a finite-difference time-domain (FD-TD) algorithm. The technique is used to calculate the tangential electric fields on the boundaries between different sized cells in a variable step size mesh environment. A waveguide is modeled in two dimensions and the accuracy of the mesh refinement algorithm is tested by measuring the amount of field reflected during the transition from a coarse mesh to a fine mesh. The amount of error is found to be less than 1%.<>