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