基于双窗全相位FFT的激光多普勒频率提取与校正方法

针对于激光多普勒信号解算中存在的频谱泄露以及栅栏效应等问题,将性能更优异的汉宁自卷积窗(HSCW)以及全相位频谱分析(apFFT)运用于多普勒信号的短时傅里叶变换(STFT)中,并且通过双谱线法对所获得的频谱进行了校正。理论与仿真表明,双汉宁自卷积窗(HSCW)apFFT比传统apFFT更能抑制旁谱泄露,并且相对于传统FFT,双HSCW窗apFFT所提供的的频谱位置与幅值能够更好的满足双谱线校正法频率校正的要求。通过将该种算法应用于高冲击下加速度传感器的校准系统中,实测结果表明,其解算结果与标准传感器的加速度峰值误差在1 %左右。

Frequency extraction and correction based on double-window all-phase FFT of laser Doppler

For the problems of spectrum leakage and fence effect in laser Doppler signal solution,The Hanning Self-Convolution Window(HSCW) and the All-Phase Spectrum Analysis(apFFT) with better performance are applied to the Short-Time Fourier Transform(STFT) of the Doppler signal.The obtained spectrum is corrected by the double-spectrum lines method.The theory and simulation show that the double Hanning self-convolution window(HSCW) apFFT can suppress the side spectrum leakage more than the traditional apFFT,and the spectral position and amplitude provided by the double HSCW window apFFT can better satisfy this method for frequency correction compared to the traditional FFT.By applying this algorithm to the calibration system of the acceleration sensor under high impact,the measured results show that the error between the algorithm and the standard sensor is about 1 %.