A comparison of the dispersion error of higher-order finite-difference time-domain schemes with Daubechies´ multi-resolution time-domain schemes

For electrically large problems, the numerical dispersion inherent in the classical Yee finite-difference time-domain (FDTD) algorithm can introduce significant errors. The 3D dispersion errors of the higher-order FDTD schemes as developed by Zhang and Chen (2000) are compared with the same size computational stencil MRTD schemes using Daubechies´ scaling functions (Fujii and Hoefer, 2000). The accuracy of both the higher-order FDTD schemes and the Daubechies MRTD schemes are compared via direct evaluation of the dispersion relation governing each algorithm. An optimal or near optimal Courant number is used for each scheme to further reduce numerical dispersion.