Weak-form BCGS-FFT combined with DCIM for analysis of electromagnetic scattering from 3D object in planarly multilayered media

An efficient algorithm is presented for 3D volume EFIE in layered media. In the handling procedure of stabilized bi-conjugate gradient fast Fourier transform (BCGS-FFT), discrete complex image method (DCIM) is introduced to dramatically accelerate calculation of time-consuming "Sommerfeld integral" in dyadic Green\´s function (DGF). Before which, DGF is spit to circumvent difficulties in utilizing DCIM in volume EFIE. In this paper, a two-step pole-searching procedure is used to extract the "surface-wave poles", and then a two-level generalized pencil of function (GPOF) method is utilized to realize DCIM, which ensure DCIM agree well with numerical integration in tens of wavelengths. At last, several reported numerical examples are newly presented to demonstrate the accuracy and efficiency of this algorithm.