激光多普勒双光束双散射模式测速技术研究  

Investigation on Dual-beam and Dual-dispersion Laser Doppler Speedometer

作　　者：黄富瑜[1] 李勇[2] 沈洪斌[1] 李莉[1] 周水庆[1] 王元铂[1] 

机构地区：[1]军械工程学院光学与电子工程系,河北石家庄050003 [2]河南质量工程职业学院,河南平顶山467000

出　　处：《应用激光》2009年第3期244-247,共4页Applied Laser

摘　　要：采用双光束—双散射模式对气流的流速进行了测量,得到了多普勒频移信号,并对信号进行了滤波处理,提高了信噪比。滤波后的信号经数字相关处理器进行二值化和自相关运算处理后,得出气流的流动速度,进而得到时间函数曲线和速度分布直方图。将测量结果与某时刻速度的理论计算结果进行比较,测得速度与计算值偏差为0.3%,根据统计结果,测得速度的标准差为5.29%。最后对影响测量精度的因素进行了分析,通过前置滤波放大器降低了系统噪声,实验结果表明该方法对气流速度测量具有较高的精度。The transverse velocity of a moving airstream is measured by using dual beam and dual-dispersion mode, and Doppler frequency signals are recorded. Signal data filtering is carried on to enhance SNR. Signals after being filtered are disposed through binarization and autocorrelation, and the floating velocity is gained. Thus the time function curve and bar chart of velocity distributing are showed. Comparing the geodesic result and calculated result of one time, the deviation is 0.3%, and the standard deviation of the geodesic based on the result of statistic result is 5.29%. At the end, the factors influencing the precision are analyzed, it indicates that system noises can be reduced by filtering amplifier, and the result shows the precision of laser Doppler speedometer is high in this method.

关 键 词：多普勒测速 双光束-双散射 二值化 自相关 

分 类 号：TP332[自动化与计算机技术—计算机系统结构] TH824[自动化与计算机技术—计算机科学与技术]