摘要
热层大气风速的测量可以采用干涉法来进行,由于光源(气辉辐射谱线)的强度很弱,故干涉法对测量系统要求很高。利用半导体激光器(LD)的调制特性和法布里-帕罗干涉仪(FPI)的高光谱分辨能力设计了一种用简单设备进行大气风场模拟与测量的方法。改变LD的驱动电流使其输出激光频率改变,从而模拟气辉辐射的多普勒频移,通过分析FPI获得的干涉图可检测出该频移,进而得到等效风速。模拟风速的相对误差不超过6.5%,最小模拟风速为20.01m/s,且测量结果与LD的线性调制特性很相符。使用该方法可以有效地对多普勒风速测量原理、数据处理方法、系统性能以及测量误差进行分析和评估。
Interferometer can be used in the measurement of thermospheric wind velocities and there are strict requirements on the measurement system since the intensity of source （emission of airglow） is very weak. Based on the modulation property of a laser diode （LD） and high optical spectrum resolving power of Fabry-Perot Interferometer （FPI）, a method to simulate wind velocity with simple equipment is discussed. Doppter＇s shift of airglow is simulated by changing the modulation current of LD, which leads to change in frequency of output laser. The equivalent wind velocity can be derived by analyzing interferometric images obtained by FPI. Relative errors of simulated velocities are less than 6.5%, and the least simulated velocity is 20.01 m/s. The results agree with the liner modulation property of LD perfectly. This method can be applied in analysis and evaluation of the principles, data processing methods, system performance and measurement errors.
出处
《应用光学》
CAS
CSCD
北大核心
2009年第2期285-290,共6页
Journal of Applied Optics
