外加正交电磁场等离子体中电磁波透射特性  

Transmission Characteristics of Electromagnetic Waves in Plasma with External Orthogonal Electromagnetic Fields

作　　者：张洁[1] 赵善超 张国栋 ZHANG Jie;ZHAO Shanchao;ZHANG Guodong(College of Physics and Electronic Engineering,Northwest Normal University,Lanzhou 730070)

机构地区：[1]西北师范大学物理与电子工程学院,兰州730070

出　　处：《空间科学学报》2021年第6期881-886,共6页Chinese Journal of Space Science

基　　金：甘肃省科技计划项目(20JR10RA080);西北师范大学青年教师能力提升计划项目(NWNU-LKQN-17-14)共同资助。

摘　　要：在基于磁流体动力学和电磁波传播理论的基础上,针对航天飞行器再入过程中的黑障问题,提出了一种物理模型.利用数值分析方法,研究电磁窗周围的电子密度在不同的飞行器轴向距离下,随着飞行器法向距离增加呈现出的变化趋势;改变外加电场和磁场的交叉角度,分析不同角度下电磁窗周围电子密度的变化趋势;研究有外加正交电磁场的电子密度与无外加电磁场电子密度比值的变化趋势和电磁波衰减的变化趋势.结果表明:当外加正交电磁场时,接收天线周围的电子密度随飞行器法向距离的增加而不断减小,其与无外加电磁场时电子密度之比呈现不断下降的趋势;电磁波的衰减在不同飞行高度和外加磁场强度下,随着电磁波频率的增加而不断减小.这为减缓“黑障”问题提供了一种新的方法.On the basis of Magnetohydrodynamics(MHD)and the theory of electromagnetic wave propagation,a physical model is proposed to solve the blackout in the reentry process of spacecraft.By means of numerical analysis,the variation trend of the electron density around the electromagnetic window is studied with the increase of the normal distance of the aircraft model under the premise of different axial distances of the aircraft model;the variation trend of electron density around the electromagnetic window is analyzed by changing the cross angle of the applied electric field and magnetic field;the variation trend of the ratio of electron density after applying an orthogonal electromagnetic field to electron density without applying electromagnetic field and the variation trend of attenuation of electromagnetic wave.The results show that when the orthogonal electromagnetic field is applied,the electron density around the antenna decreases with the increase of the normal distance of the aircraft,and the ratio of electron density to that without the applied electromagnetic field shows a decreasing trend.Attenuation of the electromagnetic wave decreases with the increase of electromagnetic frequency at different flying heights and magnetic field strength of the applied magnetic field.This provides a new method to alleviate the blackout.

关 键 词：黑障 电磁窗 等离子体鞘套 电磁波衰减 

分 类 号：P354[天文地球—空间物理学]