基于转动拉曼测温激光雷达数据采集系统的阈值校正和延时补偿技术  

Threshold Amendment and Time-Delay Compensation of Rotational Raman Lidar for Atmospheric Temperature Measurement

作　　者：孔卫国[1] 陈思颖[1] 张寅超[1] 陈和[1] 邱宗甲[1] 王玉诏[1] 刘鹏[1] 倪国强[1] 

机构地区：[1]北京理工大学光电成像技术与系统教育部重点实验室,北京100081

出　　处：《激光与光电子学进展》2011年第2期73-79,共7页Laser & Optoelectronics Progress

基　　金：国家973计划(2009CB72400402);国家自然科学基金(40905016)资助课题

摘　　要：针对转动拉曼测温激光雷达数据采集系统中光子计数卡各通道阈值及延时之间的误差,结合光子计数卡的工作原理以及方波信号幅值电压的波动性,构建阈值测量系统,以方波信号作为通道的输入,通过调整阈值电压设定值,使计数值达到最大的方法对通道的阈值误差进行了测量,并对其进行了曲线拟合。构建延时测量系统,测量各通道之间的延时差,并提出了对其进行补偿的方案。对阈值误差测量数据及拟合结果进行了分析,分析结果表明通过拟合曲线对各通道阈值电压进行设定,可更快地设置所要求的阈值电压。对延时差的补偿可以使温度分布廓线定位精度提高约10m。Differences exist among the trigger channel and two count channels of multiscaler,which is an essential component of the rotational Raman lidar system for atmospheric temperature measurement,both in the threshold and time-delay aspects,and they will impact the temperature measurement results.A measuring system is established for the threshold differences,based on the working principle of the multiscaler and the voltage fluctuation of square waves.In the measuring system,square waves with different voltage values are input to the two count channels successively.Through changing the set threshold value,the count value will be at the peak under a particular set threshold value.By this way,pairs of respective set threshold values of the two count channels corresponding to the same input square wave can be obtained,and furthermore the threshold curves can be fitted.One more measuring system is established for the time-delay differences,and the method for compensating the differences is also proposed.Analysis shows that with the threshold value set according to the fitted curves,the appropriate thresholds can be set more quickly,and the positioning accuracy of atmospheric temperature profile can be improved by about 10 m with the time-delay differences compensated.

关 键 词：大气光学 转动拉曼激光雷达 阈值校正 延时补偿 光子计数 

分 类 号：TN958.98[电子电信—信号与信息处理]