目标电磁散射极点的不变性特征分析

对频域磁场积分方程在离散化的基础上进行了矢量分析，发现离散化后的矩阵方程中含有频率因子的算子矩阵仅包含了反映散射体形状的矢量信息，从而得出极点的分布只依赖于目标的外部形状信息这一结论；然后利用FDTD进行了仿真研究，从不同姿态角(散射方向)的后时响应数据中提取了极点，结果保持了较好的一致，进一步证实了目标姿态角的改变不会影响极点的分布这一特征。

Analysis of the Invariability of Target Electromagnetic Scattering Poles

The magnetic field integral equation is analyzed in vector way after it is discreted in frequency domain. It can be found that the arithmetic operator which includes frequency element in the matrix equation only contains the vector information of the scattering body's shape. So we can draw a conclusion that the distribution of poles is only due to the exterior shape of the scattering body. We also studied this problem with FDTD method, calculated the cone's poles from the scattering data in late time in different scattering directions, and found that the position of poles are all agreed with the theoretical results well. It is proved that the distribution of poles can not be affected by the change of target pose.