改进高阶FDTD(CM24)比FDTD(2,4)高阶方法精度更高，容易编程实现，且易与并行技术结合，适合求解三维电大尺寸的时域电磁问题。但目前还没用于电磁散射的研究。.本项目首先研究CM24高阶散射模型：1）建立CM24的入射波加载模型。推导CM24高阶总散场边界条件；实现入射波在一维网格与三维计算主网格中传播的数值色散匹配，且保持入射波长时间传播后不失真；将入射波无泄漏地引进CM24的总场区域。 2）建立CM24高阶局部共形网格技术，实现对目标曲面的精确建模。CM24的计算公式是从麦斯韦积分方程推导而来，而局部共形技术也是基于环路积分思想，二者易于结合。3）研究高阶共形网格不稳定性的根源，结合显性无条件稳定技术，实现不减小时间步长下的稳定计算。.最后，结合CM24与准静态方法，模拟微动目标的时域回波序列。基于CNN机器学习方法，自动获取微动特征，实现目标智能识别。

A new conservative high-order modified FDTD(2,4) Scheme can acquire higher computational accuracy than FDTD(2,4). When computing by CM24, we are able to program easily and combine it with parallel technique to solve electrical large dimension problems. However, CM24 hasn’t been researched on problems of electromagnetic scattering..We first establish CM24 high-order scattering model: 1) The model of introducing incident wave into CM24 total region is established. High-order total-scattered field boundary condition is derived. We keep the same numerical dispersion of incident wave propagating in 1D auxiliary grids as that in 3D CM24 main computational grids. And the waveform of incident wave will not be distorted when propagating a long distance with long time. Incident wave is introduced into CM24 total field region without leakage. 2) A CM24-compatible conformal algorithm is established in order to model curves of objects accurately. CM24 formula are derived from integral equations. Conformal technique is also base on the contour integral method so that they can be cooperated easily. 3) Based on explicit unconditionally stable algorithm, the root of the unstability of high-order conformal technique is studied. We try to achieve stability of the CM24 conformal technique without reducing the time step..Finally, we simulate time-domain scattered fields from the objects with micro-motion at different time arrays, combing CM24 and quasi-static method. Based on CNN method, the feature of micro-motions of object is acquired automatically and targets can be detected intelligently.