基于小波去噪的激光多普勒振动信号处理

Laser Doppler vibration signal processing based on wavelet denoising

为了降低激光多普勒振动信号中噪声产生的影响,采用基于改进小波去噪算法的激光多普勒振动信号处理方法,将尺度引入阈值函数,确立新的评价指标用于选择最优分解层数,从而来改进小波阈值去噪算法,并利用改进的算法处理振动信号,进行了仿真分析和实验验证,取得了处理前后的振动数据。结果表明,改进算法处理仿真信号的信噪比比原有算法提升19.4%;实验测得音叉振动频率为515Hz,与实际音叉频率基本吻合。这一结果对降低激光多普勒振动信号中噪声的影响、获取振动状态是有帮助的。

In order to reduce the interference of noise in laser Doppler vibration signal,a laser Doppler vibration signal processing method based on improved wavelet de-noising was proposed.The scale was introduced into the threshold function,and a new evaluation index was established to select the optimal decomposition level.The improved algorithm was used to process the vibration signal.The improved algorithm and the original algorithm were adopted for processing the vibration signal.The simulation analysis and experimental verification were then carried out,and the vibration data before and after processing were obtained.The results indicate that the signal-to-noise ratio of simulated signals processed by the improved algorithm is 19.4%higher than that of the original soft and hard threshold algorithm.The measured tuning fork vibration frequency is 515Hz,which is consistent with the actual tuning fork frequency.This result is helpful to reduce the influence of noise in the laser Doppler vibration signal and obtain the vibration state.