基于平衡流场的再入飞行器电磁散射特性分析

针对高速再入飞行器穿过大气层时产生冗长等离子尾流的特点，综合利用真实气体效应情况下等离子体流场计算方法和移位算子时域有限差分电磁散射建模方法。首先由再入飞行器相关参数得到其周围非均匀等离子体流场的分布情况，然后据此建立含等离子体尾流目标的电磁散射模型。以锥球形目标为例，计算和分析了以零攻角再入时的低频电磁散射特性。结果表明,当飞行器再入速度较高时，等离子体尾流在低频段将显著增强其后向散射，有利于低频雷达探测再入目标。

Analysis of electromagnetic scattering characteristics of the reentry vehicle based on equilibrium flowfields

A redundant plasma wake is produced when the high speed reentry vehicle cuts through the atmosphere. Accordingly, the plasma wake calculation method under the condition of real gas effect and the shift operator finite difference time domain method are utilized comprehensively. Firstly, the distribution of the inhomogeneous plasma flowfield is achieved by the relative parameters of the reentry vehicle, and hereby the electromagnetic scattering model of the plasma wake target is established. Taking the cone spheroid target as an example, the low frequency electromagnetic scattering characteristics are calculated and analyzed when it cuts through the atmosphere with a zero attack angle. The results demonstrate that the back scattering of the reentry vehicle with a high speed is dramatically enhanced at low frequency band by the plasma wake, from which the low frequency radar will benefit in detecting reentry vehicles.