摘要
This paper discusses how to apply the two-level approximate discrete complex image method to fast and accurately compute the low frequency Green’s functions. Through numerical simulation, the approximate parameters in the computation of low frequency electromagnetic field are determined as following: 1) sampling number N of spectral Green’s function in the two-approximate integral interval is ten times of the number of approximate polynomial M; 2) the integral interval is about 40/r, where r is the offset; 3) the conjunction value L1 of the two level integral interval is Q times of the ratio of the total size of the integral interval L2 and the sampling number N1 of the second integral interval; and 4) the optimal value of Q is determined by the cross point of the spectral Green’s function approximate error against Q and the horizontal axis.