Abstract: The surface–volume–surface electric field integral equation (SVS-EFIE) can lead to complex equations, laborious implementation, and unacceptable computational complexity in the method of moments (MoM). Therefore, a general matrix equation (GME) is proposed for electromagnetic scattering from arbitrary metal–dielectric composite objects, and its enhanced solution is presented in this paper. In previous works, MoM solution formulation of SVS-EFIE considering only three-region metal–dielectric composite scatters was presented, and the two-stage process resulted in two integral operators in SVS-EFIE, which is arduous to implement and is incapable of reducing computational complexity. To address these difficulties, GME, which is versatile for homogeneous objects and composite objects consisting of more than three sub-regions, is proposed for the first time. Accelerated solving policies are proposed for GME based on coupling degree concerning the spacing between sub-regions, and the coupling degree standard can be adaptively set to balance the accuracy and efficiency. In this paper, the reformed addition theorem is applied for the strong coupling case, and the iterative method is presented for the weak coupling case. Parallelism can be easily applied in the enhanced solution. Numerical results demonstrate that the proposed method requires only 11.6% memory and 11.8% CPU time on average compared to the previous direct solution.

任意金属–介电混合体面体面电场积分方程（SVS-EFIE）的增强解

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