FDTD mesh generation algorithm based on STL file

For the calculation of complex targets by using the finite-difference time-domain(FDTD) method, an improved algorithm is proposed to directly transform the unstructured grids into Yee grids. Based on the ray intersection method, the algorithm updates the ray equation with its intersection to the triangle surface element, leading to a rapid mesh generation scheme. Also, it reduces the computational complexity and enhances the efficiency of meshing. Examples, from dielectric balls, warships, and F22 aircraft models, verify this algorithm can facilitate the FDTD calculation of large-scale complex targets.