多普勒效应对雷电源辐射定位的影响

Influence of Doppler effect on the radiation positioning of the thunder source

利用电磁辐射信号进行雷电源探测和定位是当前雷电研究的重要探测手段,其定位结果的准确性对正确认识闪电的放电机理非常重要。本文通过数学推导建立了多普勒效应在球坐标下的定位影响理论模型;用Matlab软件进行模拟,分析了多普勒效应对阵列接收信号的影响及误差,研究了多普勒效应对运动雷电源定位结果产生的影响。研究结果表明,多普勒效应对于不同类型、不同距离、不同高度的闪电影响程度不同;根据雷电发展的不同阶段,雷电源的运动速度不同,多普勒效应带来的误差也不同,且其带来的误差是不可忽略的。该研究对实现更高时空分辨力的运动雷电源定位结果和雷电的精细化研究具有重要意义。

The employment of electromagnetic radiation signal is an important detection means in current lightning research,and the accuracy of its positioning results is very important to correctly understand the discharge mechanism of lightning.In this paper,the theoretical model of the Doppler effect on the array and on the localization result of the motion lightning source is built.The results show that the Doppler effect affects at different degrees on the lightning of different types,at different distances and heights.When the speed of the lightning source is different,the Doppler effect is different as well,and the errors cannot be negligible.This work is important for the motion lightning source localization at higher spatiotemporal resolution and the refined study of lightning.