激光多普勒测速仪中的频谱分析技术

为了提高激光多普勒测速仪的测速精度,将频谱分析技术应用于多普勒信号的处理中,先对信号进行频谱细化,再对细化后的频谱进行校正。阐述了几种常见的频谱细化和频谱校正算法的基本原理,并对它们的频谱分析精度和运算量进行了比较。在Matlab平台上将它们应用于理想正弦信号进行仿真,比较了各种算法的优缺点,最后将频谱细化和频谱校正技术应用于实测多普勒信号的处理中。仿真和实验结果表明:频谱细化技术可以大大提高激光多普勒信号的频谱分辨率,频谱校正技术可以准确地校正多普勒频率,减小信号处理的误差。将其运用于激光多普勒测速仪中切实可行,为设计高精度的激光多普勒测速仪创造了条件。

Frequency analysis technology in laser Doppler velocimeter

A new method of signal processing was proposed in order to eliminate the noise interference and enhance the measurement accuracy of laser Doppler velocimeter(LDV).The frequency spectrum zooming and frequency spectrum correction technology were applied in the signal detection system of LDV.Basic principle of frequency analysis algorithms was briefly introduced,and then spectrum simulations of ideal sinusoidal signals were studied based on these algorithms.Goertzel zooming method and ratio correcting method were applied in realtime Doppler signal measurement.The simulation and experimental results indicate that resolution of frequency spectrum can be improved by frequency spectrum zooming technology and the accuracy of signal processing can be greatly improved by frequency spectrum correction technology.The frequency spectrum resolution and measurement accuracy of LDV system with the frequency analysis technology can be obviously improved.This application creates conditions for the design of high accuracy LDV.