Fast algorithm for simulating 3-D electromagnetic inverse scattering in horizontally stratified medium via DTA
水平层状介质中基于DTA的三维电磁波逆散射快速模拟算法

Two kinds of approximations called DTA1 and DTA2 for integral equations are obtained according to different back substituting method on the basis of diagonal tensor approximation(DTA) in order to improve the efficiency for simulating 3-D electromagnetic scattering and inverse scattering in horizontally stratified medium.The approximations can be used as the initial guess and pre-conditioner in the stabilized biconjugate-gradient fast Fourier transform(BCGS-FFT) algorithm for computing integral equations,and hence a hybrid DTA-BCGS algorithm with higher efficiency is formed.Numerical scattering examples have shown the high accuracy of DTA2 and the high efficiency of hybrid DTA-BCGS algorithm,especially of hybrid DTA2-BCGS.Since DTA2 has a much higher accuracy,it is combined with distorted Born iterative inversion method(DBIM) and a fast electromagnetic inverse scattering technique is formed to reconstruct 3-D inhomogeneous objects.Numerical inverse scattering examples have demonstrated the efficiency of the inverse scattering technique in reconstructing arbitrary 3-D inhomogeneous objects in horizontally stratified medium.