An Efficient Solution for Electromagnetic Scattering by Multi-layered Spherical Structures

This work proposes an efficient method for calculating the electromagnetic scattering by a multi-layered sphere. Under the framework of BoR-MoM, an innovative method for dealing with the singularity in the Modal Green’s function is put forward. The modal Green’s function is divided into the singular and non-singular components. The Fourier coefficients of the singularity part are given in a semi-analytical way, which are applied to the calculation of the impedance matrix. Furthermore, FFT helps to execute the algorithms and reduce the computational complexity effectively. Numerical simulations demonstrate that, in the case of a large problem tested, where about 105 wavelengths are included along the generatrix of a perfectly electrically conducting (PEC) sphere, only 0.67 s with 630 sampling points are required to achieve a relative error of 0.21%. While 1.88 s with 1082 cylindrical and spherical functions by Mie scattering is required. The proposed method offers an alternative accurate way for the scattering solution of a multi-layered sphere instead of the Mie method.