The dispersion characteristics of the FD-TD method

The numerical phase and group velocity characteristics of the three-dimensional FDTD (finite-difference time-domain) algorithm are derived from the dispersion relation for wave propagation in the TEM, TE, or TM mode. From these dispersion characteristics, numerical errors due to dispersion can be easily assessed and would be used in determining the mesh size and the stability factor in order to minimize such errors.<
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