斜拉桥健康监测信号改进小波相关降噪

Improved Wavelet Correlation De-noising on Cable-Stayed Bridge Health Monitoring Signal

为提高斜拉桥健康监测动态信号的降噪效果,针对传统小波相关降噪算法的缺陷,提出一种改进小波相关降噪算法。该算法将各层小波系数的主要能量周期作为相关检测邻域范围,并根据斜拉桥动态响应信号特征设置降噪阈值,最后采用一种全新的信号重构算法,得到降噪后的信号。将该算法与传统小波相关降噪和小波默认阈值降噪算法进行仿真试验比较,结果表明,改进小波相关降噪算法具有较好的降噪效果,能够应用于斜拉桥健康监测动态响应信号的降噪处理。

To enhance the dynamic signal de-noising effects of cable-stayed bridge health monitoring,an improved wavelet correlation de-noising algorithm is proposed in order to deal with defects of traditional one.The improved algorithm uses the main energy periods of wavelet coefficients of each layer as the correlation detection neighborhood sizes,and sets a de-noising threshold on the basis of the characteristics of cable-stayed bridge dynamic response signal.Finally the de-noised signal is obtained by a new algorithm on signal reconstruction.Two algorithms,called the traditional wavelet correlation de-noising and wavelet default threshold de-noising algorithms,are compared with the improved one in series of simulation experiments.The results show that improved wavelet correlation de-noising algorithm has better denoising effect,thus it can be used in dynamic signal de-noising of cable-stayed bridge health monitoring.