Introducing a Sub-cell Tensor Technique into a (2,4) FDTD Method

摘要

A sub-cell tensor based technique for modeling dielectric interfaces is introduced into a (2,4) FDTD method. For each cell containing an interface, a tensor based method that enforces continuity conditions is used to determine the fields on both sides the sloped interface. These fields are then volumetrically averaged. The approach is used to calculate a corrected field value at each grid point of the large fourth-order stencil. The combined algorithm is computationally homogeneous, unlike most previous algorithms of this type, and thus lends itself to parallel processing. Additionally, the method may be used with other higher-order stencils. The accuracy is tested using the exact Mie series solution for scattering from a dielectric sphere. It is shown that using the (2,4) tensor method results in ～50-70% less error than the (2,4) standard Yee method in the vicinity of a dielectric sphere.