摘要
讨论了一种新的超声信号到达时间检测方法.运用小波的奇异点定位功能,将小波函数为拟小波的小波变换与希尔伯特变换相结合,对经过希尔伯特变换后的超声波信号进行5层小波分解,利用分解结果计算出超声波信号到达接收超声传感器的时间.实验中用超声传感器采集空气中传播的超声波数据测试结果,得到较精确的结果.与一般的小波变换处理的结果相比较,此方法对检测在任意时间区间上为一致L ipsch itz∞的具正弦函数特性的超声波信号的到达时间点比较适用.
A new method for time-arrival location of ultrasonic signal is developed in this paper. Using wavelet singularity detection, wavelet decomposition and Hilbert transform are combined to decompose the received ultrasonic signal to 5 levels after HUbert transform, then to locate the arrival time of the received signal. Tests with sampled ultrasonic data sequence show good validity of this method. Compared with the results derived from wavelet decomposition with out Hilbert transform, this method is better in detecting the arrival time of ultrasonic signal with characteristic of sine wave which is uniformly Lipschitz at any time interval.
出处
《武汉理工大学学报（交通科学与工程版）》
2006年第5期873-876,共4页
Journal of Wuhan University of Technology（Transportation Science & Engineering）
基金
江苏省高校自然科学研究项目资助(批准号:02KJD460005)
关键词
小波变换
拟小波
奇异性
希尔伯特变换
wavelet transform
quasi wavelet
singularity
Hilbert transform
