Efficient Discontinuous Galerkin Integral Equation Method for Electromagnetic Modelling of Multi-Scale PEC Objects

To meet the increasing demand of high-fidelity electromagnetic simulations, the discontinuous Galerkin method is introduced into surface integral equation (SIE) methods and surface-partition based domain decomposition SIE methods are proposed for efficiently simulating opening electromagnetic problems from electrically large and multi-scale PEC objects. In this paper, the multilevel fast multipole algorithm (MLFMA) is applied to accelerate the solution of the resulting matrix equation, and a new restricted overlapping preconditioner based on MLFMA oct-tree boxes is proposed to effectively improve the iterative convergence. Comparing with the existing domain decomposition based preconditioner, the new preconditioner is easy-to-implement, resource saving, and not sensitive to the transmission conditions at contour boundaries between subdomains. The performance of the discontinuous Galerkin domain decomposition method of SIE equipped with the new preconditioner is demonstrated by numerical experiments.