A Domain Decomposition Method for Electromagnetic Radiation and Scattering Analysis of Multi-Target Problems

A domain decomposition method is presented for analyzing electromagnetic problems involving multiple separable scatterers. The method first decomposes the original problem into several disjoint subregions. In each subregion, the domain decomposition method is further applied by decomposing the region into smaller, possibly repeated, subdomains. The domain decomposition method is general enough for arbitrary geometries, but is also capable of exploiting repetitions. This renders geometrically complicated and electrically large subregion problems tractable. The subregions communicate through the near-field Green's function. To overcome the vast computational costs required in exchanging information between electrically large subregions, the adaptive cross approximation algorithm is adopted to expedite the process. The method is applied to study radiation characteristics of a reflector antenna system and an antenna array in the presence of a frequency selective surface to demonstrate the utility of the present approach.