高超声速目标的电磁散射特性研究一直是天基、地基和海基雷达对高速目标实时监测、解决再入“黑障”问题的一个重要需求。由于飞行器在高速飞行时，其头部至尾部对空气的电离度是不同的，这就形成了飞行器迎风面与背风面等离子体流场中各个参数在空间中大梯度分布且时变的特性。在这种情况下，很多传统的数值方法和解析方法难以对飞行器迎风区与背风区的电磁散射场得到理想的计算结果。为此我们引入一种新网格进行Maxwell方程的离散推导——面中心立方体（Face-centered cube, FCC）网格。FCC网格是一种类似于晶体结构的空间分布网格，同时由于FCC网格的间隔采样点多，在处理复杂介质，尤其是介质参数存在大梯度变化时，其稳定性条件比传统的Yee元胞更好，对非均匀介质引起的色散误差也有很大的提升。本项目将采用FCC-FDTD方法对非均匀大梯度和时变特性的等离子体鞘套及其高速目标电磁散射特性展开计算和分析。

The study of hypersonic targets’ electromagnetic (EM) characteristics has always been an important requirement of space-based, ground-based and sea-based radar for real-time monitoring of high-speed targets and solving the problem of re-entry "blackout". During flight of hypersonic vehicle in near space, the ionization degree of air in the head and tail of aircraft is different, which results in a large gradient distribution and time-varying characteristics of the parameters in the plasma flow on the windward and leeward surfaces of the aircraft. In this case, many traditional numerical and analytical methods are difficult to obtain perfect results. For this reason, we introduce a new mesh for the discrete derivation of Maxwell equation- Face-centered cube (FCC) mesh. FCC grid is a kind of a spatial distribution grid similar to crystal structure. Because of the dense distribution of field components in the FCC mesh, the stability condition of the FCC mesh is better than that of the traditional Yee cell for the complex media, especially when the medium parameters have large gradient changes. During the research the FCC-FDTD method is adopted to calculate and analyze the EM characteristics of high-speed targets combined with the non-uniform and time-varying plasma model.