频谱细化及频谱校正技术在激光多普勒测速仪中的应用

Application of frequency spectrum refinement and correction technology in laser Doppler velocimeter

提出了对多普勒信号先进行频谱细化,再进行频谱校正的方法,阐述了几种常见的离散频谱细化和频谱校正算法的基本原理,并运用它们对不同频率的理想正弦信号和实测的多普勒信号进行谱仿真和实测研究。理论分析和实验结果表明:频谱细化算法中Goertzel细化算法所需的运算量最少,计算速度最快;频谱校正算法中比值校正算法校正公式简单,运算量少,且校正精度较高;频谱细化和频谱校正技术大大提高了频谱分辨率,将其运用于频谱分析型激光多普勒测速仪中切实可行。

In this paper, frequency spectrum refinement and frequency spectrum correction method for Doppler signal was proposed separately. Basic principle of frequency spectrum refinement and frequency spectrum correction algo-rithm was expounded. Spectrum simulation of different frequency ideal sinusoidal signal and real-time Doppler signal were studied based on these theories. Theoretical analyses and experimental results demonstrated that, the Goertzel re- finement algorithm has the least computing amount and the quickest computing speed ; the ratio correction algorithm for frequency correction has simple correction formula,less computing amount and higher correction accuracy. Resolution of frequency spectrum can be improved by frequericy spectrum refinement and correction technology ,which is practical useful in frequency spectrum analyzing laser Doppler velocimeter.