Method of Moment Weighted Domain Decomposition Method for Scattering From Large Platforms

Abstract

General theory of the Method of Moments weighted domain decomposition method (MoM weighted DDM) is proposed for time-harmonic scattering from composite objects using surface integral equations (SIEs). The MoM weighted DDM is a triple-step iterative method applied to the SIE problem decomposed into subdomain problems. In the first step of each iteration, the subdomain problems are solved without mutual coupling taken into account. In the second step of each iteration, all subdomain solutions from the current and all previous iterations are linearly combined with weights that are determined by the MoM. In the third step of each iteration, the residual of the original SIE problem is found, which is to be used as the excitation in the next iteration. This novel approach features fast convergence and high compression rate of the initial set of bases, thus enabling solution of electrically large scatterers. The compact matrix representation enables easy implementation using a direct MoM solver as a numerical engine and easy parallelization. In the implementation of the method, additional acceleration is achieved using the concepts of active subdomains and far-field approximation. The effectiveness of the method is demonstrated on a model of a combat airplane analyzed up to 20 GHz (1000 wavelengths).