An Efficient Electromagnetic Scattering Analysis Method for Multiple Objects Based on Characteristic Modes and MLFMA

An efficient method, characteristic mode-multilevel fast multipole algorithm-clustering (CM-MLFMA-Clustering) method, is proposed for analyzing electromagnetic scattering in multi-object systems. This approach integrates theory of characteristic modes (TCM) with the fast multipole method (FMM) to accelerate the computation of total scattering contributions, including individual object scattering and mutual coupling effects. To accurately account for mutual coupling effects induced by scattering fields between objects, we introduce a novel coupling modal weighting coefficient (CMWC), extending the conventional modal weighting coefficient (MWC). The total scattering fields are obtained through a linear superposition of dominant modes weighted by both MWC and CMWC. Additionally, a dual-scheme FMM is proposed to enhance computational efficiency. The first scheme employs MLFMA for pairwise electromagnetic coupling calculations, while the second scheme utilizes a K-means clustering algorithm to efficiently manage large multi-object systems. Numerical results confirm the method’s accuracy, demonstrating a significant reduction in memory requirements and computational complexity, achieving approximatelyO(N)scaling observed in numerical simulations.