Domain Decomposition Method Based on Integral Equation for Solution of Scattering From Very Thin, Conducting Cavity

In this communication, a novel domain decomposition method (DDM) based on integral equation is developed for solving scattering problems of very thin, conducting cavity. By imposing equivalent electric and magnetic currents on the aperture, the original problem is transformed into interior and exterior problems. Different from traditional method based on interior-exterior equivalence principle, this work couples the exterior and interior problems only through the transmission condition on the aperture. Based on this DDM, a well-posed combined field integral equation (CFIE) is successfully developed to realize fast solution of electromagnetic scattering from open-ended cavity with extremely thin or zero thickness. Compared to the electric field integral equation, the proposed CFIE significantly improves the convergence rate of iterative solvers. Numerical results are given to demonstrate the validity and advantages of the present method.