高层大气风场四强度测量法误差分析与计算

Error analysis of four-intensity algorithm used for the measurement of upper atmosphere

利用干涉成像光谱技术和电磁波的多普勒效应,通过测量高层大气(80—300km)中的气辉(极光)辐射线的四个干涉强度值而获知高层大气的速度和温度信息.采用四强度干涉测量法,分别对基于Michelson干涉仪的动镜扫描和基于无动镜四分区镀膜的干涉图获取模式所引起的测量误差进行了深入的理论分析与研究.给出了由于此测量误差所导致的相位误差所引起的高层大气风场速度、温度的误差数值;采用计算机模拟得出了在不同相位误差条件下,两种模式计算得到的风场速度和温度的误差分布图;给出了风速误差、温度误差与相位步进误差的关系曲线.理论计算结果表明:基于Michelson干涉仪动镜扫描探测模式的速度误差是基于无动镜四分区镀膜模式的两倍,而动镜模式的温度精度略高一些.该研究对提高高层大气风场的探测精度提供了重要的理论指导,对高层大气风场探测模式的研究以及仪器装置的研制均具有重大的理论意义和实践价值.

With imaging interferometry and Doppler Effect, the information of the upper atmosphere including velocity and temperature can be obtained by measuring four interference intensities of the aurora in the upper atmosphere （80-300 km）. Theoretical analysis of the measurement error when using four-intensity algorithm in the moving mirror model and divided mirror model is presented respectively. The error of velocity and temperature of the upper atmosphere caused by random phase error is given. By computer simulation, we get the distribution map of velocity error and temperature error in the two models. The result shows that the error of the velocity with the divided mirror model is about half that with the moving mirror model, while the moving mirror model has appreciably higher accuracy for temperature. The research can help us to improve the detection precision of upper atmospheric wind in theory. It has important theoretical significance and practical value both for the research of the detect mode and manufacture of the equipment.