An Adaptive Segmented Reduced Basis Method for Fast Interpolating the Wideband Scattering of the Dielectric–Metallic Targets

In this letter, an interpolation method, i.e., the volume surface-integral equation-based adaptive segmented reduced basis method (VSIE-ASRBM), is proposed to fast analyze the wideband electromagnetic (EM) scattering of dielectric-metallic targets. First, by integrating with the hybrid multilevel accelerated Cartesian expansion multilevel fast multipole algorithm (MLACE-MLFMA), the broadband EM scattering of electrically large dielectric-metallic targets can be calculated without repeated meshes. Second, replicative calculations of the near-region impedance element are avoided by the empirical interpolation method. Moreover, different from the iteration process of the VSIE enhanced by MLACE-MLFMA, the current distribution can be obtained mainly by calculating the far-region impedance matrix and the sampling current vector multiplications. Meanwhile, an adaptive segmented strategy is adopted to further improve the interpolation efficiency. The proposed VSIE-ASRBM has three advantages: adaptive segmented interpolation, lower interpolation memory cost, and higher interpolation efficiency. The accuracy and efficiency will be demonstrated in two numerical examples.