Effect of attack angle on the electromagnetic wave transmission characteristics in the hypersonic plasma sheath of a re-entry vehicle  

作　　者：Xin AI Qiuyue NIE Zhonglin ZHANG Peiqi CHEN Shulei ZHENG Changshi YAN Guoqiang WEI 艾昕;聂秋月;张仲麟;陈培奇;郑树磊;闫昌时;魏国强(School of Electrical Engineering and Automation,Harbin Institute of Technology,Harbin 150001,People’s Republic of China;Laboratory for Space Environment and Physical Sciences,Harbin Institute of Technology,Harbin 150001,People’s Republic of China;School of Physics,Harbin Institute of Technology,Harbin 150001,People’s Republic of China)

机构地区：[1]School of Electrical Engineering and Automation,Harbin Institute of Technology,Harbin 150001,People’s Republic of China [2]Laboratory for Space Environment and Physical Sciences,Harbin Institute of Technology,Harbin 150001,People’s Republic of China [3]School of Physics,Harbin Institute of Technology,Harbin 150001,People’s Republic of China

出　　处：《Plasma Science and Technology》2024年第12期49-62,共14页等离子体科学和技术（英文版）

基　　金：supported by National Natural Science Foundation of China(Nos.92271202 and 92371105)。

摘　　要：The attack angle may greatly affect the hypersonic plasma sheaths around the re-entry vehicle,thereby affecting the transmission characteristics of electromagnetic(EM)waves in the sheaths.In this paper,we propose an integrated three-dimensional(3D)model with various attack angles and realistic flying conditions of radio attenuation measurement C-II(RAM C-II)re-entry tasks for analyzing the effect of the attack angle on the transmission characteristics of EM waves in the sheaths.It is shown that the electron density and collision frequency of the sheath on the windward side can be increased by an order of magnitude with the increase of the attack angle.Meanwhile,the thickness of the sheath on the leeward side is increased where the electron density and collision frequency are reduced.The EM waves are mainly reflected on the windward plasma sheath due to the cutoff effect,and the radio-frequency(RF)blackout is mitigated if the antenna is positioned on the leeward side.Thus,by planning the trajectory properly and installing the antenna accordingly during the re-entry,it is possible to provide an approach for mitigation of the RF blackout problem to an extent.

关 键 词：attack angle hypersonic plasma sheath re-entry vehicle transmission characteristics 

分 类 号：V419[航空宇航科学与技术—航空宇航推进理论与工程] O53[理学—等离子体物理] O441.4[理学—物理]