光谱稳定性对直接探测多普勒测风激光雷达的影响研究

从种子注入固体激光器的不稳定和多普勒频移检测干涉仪的光谱漂移出发,模拟和分析其对基于双边缘探测技术的直接探测多普勒激光雷达风速测量准确度的影响. 模拟结果显示,在5 min积分时间的30 000个脉冲内,如果达到风速准确度1 m/s,要求激光器出现多纵模的脉冲不能超过总脉冲个数的0.06％.在干涉仪光谱稳定方面,使用两级温控可以将干涉仪温度控制在±0.002℃,对应风速误差为±0.226 m/s.同时提出通过监视种子注入过程中的脉冲建立时间和干涉仪温度,可以在数据反演时,消除激光频率跳动和干涉仪光谱漂移对风速测量准确度的影响.

Effect of Spectrum Uncertainty for Direct-Detection Doppler Wind Lidar

The wind error of the double-edge technique Doppler lidar due to the instability of injection-seeding solid laser and the drift of interferometer′s spectrum was analyzed.Corresponding numerical simulation indicated that if the wind error of 1 m/s was achieved,the unsuccessful injection-seeding pulses should be less than 0.06% in integration time of 5 min.(30 000 pulses).In the respect of spectrum drift of the interferometer,double temperature control systems were used and the accuracy of ±0.002℃ was obtained,corresponding to the wind error of ±0.226 m/s.Monitoring of buildup time of the injection-seeding laser and temperature of the interferometer was significantly to improve the invertion accuracy of wind error by rejecting the data with frequency jumping and drifting.Researches of injection-seeding and spectrum stability of the interferometer were practical for the development of double-edge wind lidar.