基于Labview的激光多普勒测速仪的频谱校正

在激光多普勒测速仪中,为了减小由信号处理算法带来的测量误差,提出运用频谱校正算法对多普勒信号的频谱进行校正,详细阐述了能量重心法、比值法和相位差法3种离散频谱校正算法的基本原理,运用这3种算法对理想正弦信号进行仿真,并运用比值法对信号施加不同频率和信噪比的噪音下的正弦信号和实测的多普勒信号进行仿真及实验研究。结果表明:3种算法都可以使信号的频率更接近于真实值,其中能量重心法校正精度相对较低,比值法和相位差法精度较高,尤其是比值校正算法处理速度更快,校正的精度基本不受信噪比的影响。将比值法运用于激光多普勒测速系统,与光接收计数法测量结果进行比较,结果显示:校正后比较正前激光多普勒测速仪测量相对精度提高了2～3倍。

Spectrum correction of laser Doppler velocimeter based on Labview

In order to decrease the measuring error of signal processing in laser Doppler velocimeter(LDV), frequency spectrum correction methods for laser Doppler signal were proposed. Basic principles of energy centrobaric correction, ratio correction and phase difference correction were expounded. The three methods processing ideal sinusoidal signals was simulated with different signal frequencies, and so was the ratio method processing sinusoidal signals with different noises and signa-to-noise ratios. The results...