临近空间等离子体鞘套对太赫兹波传播特性分析

Analysis of Terahertz Wave Propagation in Near Space Plasma Sheath

针对高超声速飞行器在临近空间巡航时出现的通信"黑障"问题,根据RAM C提供的飞行试验数据,建立一维等离子体鞘套模型,通过数值计算分析了等离子体与太赫兹波的相互作用机理,并从等离子体厚度、等离子体电子密度、等离子体碰撞频率和太赫兹波入射角等条件得到了太赫兹波在等离子体鞘套中的传输特性曲线。仿真结果表明:把太赫兹波段作为临近空间平台通信,有利于解决"黑障"问题,其中在大气窗口0.22THz处的衰减均在30dB以下。此论证结果可为临近空间平台设计的高超声速飞行器选用通信频段时提供参考。

Aimed at the problem that the communication blackout usually happens when a hypersonic vehi- cle voyage closes to the space, a model of plasma sheath is established according to the data provided by ra- dio attenuation measurement C （RAM C） voyage experiment. Through numerical calculation, the principle of interaction between plasma and terahertz wave is analyzed, and the properties of terahertz wave propa- gation in plasma sheath are obtained by changing the parameters of plasma including plasma thickness, plasma density, plasma collision frequency and terahertz wave incident angle. The simulation shows that taking the terahertz frequency band as communication frequency band in near space, this is advantageous to the solution of communication blackout problem in the value of attenuation less than 30 dB at the atmos- pheric window of 0.22 THz. The result can be used as reference for design of communication platform in the near space.