Abstract:

A conformal finite-difference time domain (FDTD) mesh-generating scheme for coated targets based on the triangle-patch is presented. For every vertex, the triangle-patches which have a common vertex should be figured out, and all the unit external normal vectors of these triangle-patches are directly summed up. The vector summation can be approximately seen as an external “average normal vector” of the common vertex. A data file about the coordinates of vertexes on coating can be got by removing the vertexes with a distance of coating thickness along their normal line, respectively. If a target is “internal coated”, then vertexes should be removed along the positive direction of normal; else if it is “externally coated”, then vertexes should be removed along the negative direction of normal. When a target is partially coated, only the vertexes on the coating part need to be removed, and the other vertexes remain unchanged. The triangle-patches data files about the original target and coating are used to generate FDTD conformal meshes for coated targets. The numerical results validate this scheme.