An efficient partial extrapolation BCGS-FFT method for solving electromagnetic scattering problems

In order to quickly solve electromagnetic scattering problem of oscillation, singularity, slow convergence in Sommerfeld integrals, a new method is proposed which is a partition-extrapolation method used to accelerate the Sommerfeld tail integral calculation, and combined with the stabilized biconjugate fast Fourier transform (BCGS-FFT) algorithm for solving electromagnetic scattering problems field distribution. First of all, the expression form of the electric field integral equation (EFIE) is given. And a convenient elliptic integral path is applied to minimize the oscillation and singularity of the sommerfeld integral in the process of solving the EFIE. The Levin extrapolation method is used at the tails of the Sommerfeld integral to improve the integral convergence speed in order to quickly fill the dyadic Green’s function matrixes. Then a variety of numerical experiments are carried out for the new method, which have verified the accuracy of the algorithm, and compared the calculation efficiency of the new method with that of the traditional BCGS-FFT method. It is found that the new method can save 20%−37% of the calculation time under the condition of maintaining the same calculation accuracy. This method can be applied to the electromagnetic scattering calculation of complex scatterer embedded in multi-layer space and provides a new method for solving the electromagnetic scattering field of target region quickly.