电离层人工调制在水平分层电离层中所激发的ELF波辐射  

Radiation of ELF waves by ionospheric artificial modulation into a stratified ionosphere

作　　者：汪枫[1,2] 赵正予[1] 常珊珊[1] 赵光欣[2] 青海银[1] 

机构地区：[1]武汉大学电子信息学院空间物理系,武汉430072 [2]武汉纺织大学电子与电气工程学院,武汉430200

出　　处：《地球物理学报》2012年第7期2167-2176,共10页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目(40804038)资助

摘　　要：通过大功率ELF/VLF调幅高频波能有效地扰动低电离层,形成等效的ELF/VLF电离层虚拟天线,用来辐射ELF/VLF波,所辐射出的低频信号可以进入中性大气层形成地球-电离层波导.本文基于调制加热模型,采用全波有限元算法计算由人工调制电离层所形成的电偶极矩所辐射出的ELF波在水平分层电离层中的波场,计算结果将与地面观测结果进行比较.模拟结果表明,所辐射出的ELF波在电离层中形成一个窄的准直波束,海面所能接收到的ELF信号强度为pT量级,并且频率越低,海面所接收到的场强就越小,与HAARP实验数据一致.结果还表明,低纬电离层对低频信号的传播衰减较大,并且所能透射出电离层的角度小,因此高纬地区更适合地球-电离层波导的激发.Using powerful high-frequency radio waves modulated at ELF/VLF can efficiently modify the lower ionosphere which can act as an equivalent ELF/VLF virtual antenna for the generation of ELF/VLF waves which can propagate in the Earth-ionosphere waveguide. In this paper, based on the modulation model, a full-wave finite element method is used to calculate the field of the ELF waves radiated by the dipole moment which is produced by ionospheric artificial modulation in the stratified ionosphere and the calculated values are compared to the ground observation. The numerical modeling shows that these waves form a narrow collimated beam and the magnitude of field intensity of low frequency signals received on the sea is ~pT which will become smaller when the frequency is lower and this result is in accordance with the laboratorydata from HAARP. The result also shows that it has stronger attenuation and small angel penetrating the ionosphere for the low signal at low latitude, so that the excitation of the Earth- ionosphere waveguide is easier at high latitude.

关 键 词：电离层人工调制 ELF波 全波解 数值模拟 HAARP实验 

分 类 号：P352[天文地球—空间物理学]