MODELING OF THIN DIELECTRIC STRUCTURES USING THE FINITE-DIFFERENCE TIME-DOMAIN TECHNIQUE

The finite-difference time-domain (FDTD) technique is applied to scattering problems involving thin dielectric sheets, conductor-backed dielectric sheets, and conductor-backed dielectric sheets containing cracks in the dielectric material. A "smart cell" technique is developed that enables these geometries to be modeled with a spatial grid that is much larger than the dielectric slab and crack widths. This technique is computationally more efficient than the "brute force" (or ordinary) FDTD approach, which must use cells small enough to resolve the dielectric sheets. Numerical results are presented which show that this technique yields accurate scattering results at a large savings in computational resources.