Group and phase velocities in the TLM-symmetrical-condensed node mesh

This paper presents the analytical expressions of group and phase velocities as a function of frequency in the TLM-symmetrical-condensed node mesh for the three fundamental directions. The direction /spl lsqb/1, 1, 1/spl rsqb/ happens to be more dispersive than the directions /spl lsqb/1, 1, 0/spl rsqb/ and /spl lsqb/1, 0, 0/spl rsqb/, giving the TLM-symmetrical-condensed formulation dispersion characteristics similar to those of the FD-TD algorithm with a Courant number of 1//spl radic/3.<
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