飞行器再入大气层时高速压缩周围气体,在高温作用下会在飞行器表面生成一层等离子体,导致通信信号难以传输,这是研究降低等离子体电磁波损耗的重要原因。文中针对电磁波在等离子体中的传播特性进行了理论分析,并在CST软件中建立了等离子体模型,仿真并分析了等离子体电波传播的损耗特性。为了改善电磁波通过等离子体层的能力,降低损耗,在等离子体区施加电场 仿真结果表明:施加电场后,对于频率f>7.25 GHz的电磁波,其在等离子体内的传播常数S21减小,传播能力提升,最大改善了6 dB。文中设计了等离子体试验箱,通过仿真研究得到了该试验箱等离子体分布,并据此研究了试验箱等离子体的电波传播能力,为实验提供理论参考。

When the aircraft reenters the atmosphere, the surrounding air is compressed due to high speed, and the plasma sheath caused by high temperature is generated which will shield electromagnetic wave communication. Therefore, it is very important to study the electromagnetic wave attenuation in plasma. In this paper, the propagation characteristics of electromagnetic wave in plasma are analyzed theoretically, a plasma model is established using CST software, and the attenuation constant in plasma is simulated and analyzed. In order to improve the propagation capability of electromagnetic wave in plasma and reduce attenuation, an electric field is applied across the plasma area. The simulation results show that the S21 of electromagnetic wave in plasma with electric field is significantly reduced when f>7.25 GHz, with maximum reduction of 6 dB. The plasma test chamber is designed, and the plasma distribution of the test chamber is obtained through simulation. Based on the distribution, the wave propagation in plasma in the test chamber is studied, which provides a theoretical reference for the experiment.

P354.4