针对临近空间飞行器的黑障问题，根据模拟的RAM C-III飞行器周围的流场分布结果，计算了等离子体电子密度和碰撞频率，并根据其分布建立了非均匀的等离子体模型。在此基础上，利用散射矩阵方法分析了太赫兹波在等离子体中的传输特性随着等离子体密度、等离子体厚度、等离子体碰撞频率的变化以及外加磁场对传输特性的影响。结果表明，太赫兹波的传输损耗随着等离子体电子密度和等离子体厚度的增加而增加，而碰撞频率的增加会使得透射率先减小后增加。在外加磁场的作用下，左旋太赫兹波的传输特性会得到改善；而对于右旋太赫兹波，磁场的施加会引入吸收峰，并且随着磁感应强度的增加向高频方向移动。

In this paper, the plasma electron density and collision frequency are calculated based on the flow field simulation of RAM C-III air vehicle, and an inhomogeneous plasma model is established according to the calculation results. The effects of plasma density, plasma thickness, plasma collision frequency and external magnetic field on the propagation characteristics of terahertz wave in plasma are analyzed using scattering matrix method. The results show that the propagation loss increases with plasma electron density and plasma thickness, while the transmittance decreases first and then increases with the increasing of collision frequency. When an external magnetic field is applied, the propagation characteristics of the left-handed polarized terahertz wave will be improved, while for the right-handed polarized terahertz wave, the application of magnetic field induces an absorption peak, which shifts to high frequency range with the increasing of magnetic induction intensity. This work may make a contribution to solving the problem of communication blackout.