A high-accuracy realization of the Yee algorithm using non-standard finite differences

New nonstandard second-order finite differences (FD's) are introduced, which when substituted into the Yee algorithm, reduce the solution error by a factor of 10/sup -4/ on a coarse computational grid. Using /spl lambda//h (grid spacings per wavelength)=8, one achieves the same accuracy as the standard Yee algorithm does at /spl lambda//h=1140. In addition, greater algorithmic stability allows a reduction in the number of iterations needed to solve a problem.