Two domain decomposition methods, SDIM and CBFM, for scattering from a two-dimensional perfectly conducting rough...

This paper focuses on the two domain decomposition methods, the subdomain decomposition iterative method (SDIM) and the characteristics basis function method (CBFM), combined with adaptive cross approximation (ACA) to compute the normalized radar cross section (NRCS) from a perfectly conducting two-dimensional (2D) randomly rough surface. The 3D electromagnetic problem is solved from the electric field integral equation discretized by the Galerkin method of moments with the Rao-Wilton-Glisson basis functions. In addition, a parametric study versus the number of blocks, the number of overlapping edges, the thresholds of recompressed ACA (RACA; ACA combined with two QR decompositions and truncated by a SVD procedure, also named ACA-SVD or ACA-TSVD), and the parameters inherent to the CBFM is investigated. The complexity of the two methods is also addressed.