Optimization of the Finite Difference Time Domain Simulations for Radar Cross Section Calculation

We optimize the Finite Difference Time Domain (FDTD) electromagnetic solver, HiFDTD, for better numerical performance on the radiation scattering problems of non-penetrable objects. Being a volumetric method, FDTD is not well suited for solving Radar Cross Sections (RCS) problems with complexity scaling as the surface of the object. In contrast to traditional FDTD solvers, in HiFDTD the 3D mesh is updated asynchronously and this allows for very efficient skipping of regions where no update is required. The performance scaling of the developed HiFDTD RCS solver version is compared for various standard scattering problems (Sphere, NASA Almond, STL Airplane) with the results obtained by the Method of Moments. We show that for large problems the performance of HiFDTD RCS scales approximately as the third power of the linear problem size.