An Enhanced Preconditioned JMCFIE-DDM for Analysis of Electromagnetic Scattering by Composite Objects

For electromagnetic wave scattering by composite conductor and dielectric objects, an efficient integral equation solver is imperative. In this letter, An enhanced preconditioned hybrid approach combining a nonconformal, nonoverlapping domain decomposition method (DDM) and electric/magnetic current combined-field integral equation (JMCFIE) is proposed. It provided a flexible method to decompose the complex composite problem into easily solvable subdomains. To prevent unphysical reflections from the touching the face of the subdomain, Robin-type transmission conditions are used across the touching face of subdomains. An enhanced preconditioned inner-outer iteration scheme is employed in which DDM acts as a block Jacobi preconditioner for the whole system as the outer iteration, and a four-partition block-diagonal preconditioner (4PBDP) that is based on self-interactions of the finest level clusters of multilevel fast multipole algorithm (MLFMA) is further used in the inner iteration solution. In numerical examples, the efficiency of the proposed scheme is shown.