Wavelet analysis of vortex signal
Hongjun Sun, Wei-jie Qu · 2009
Vortex signal is a kind of single frequency sine wave signal which is often noised. Comparing with the algorithms of time-frequency analysis, Wavelet analysis method is perfected in process of filtering and frequency detecting. This paper uses wavelet analysis method to denoise and detect both simulation signal and vortex signal, the symletA wavelet is selected to be the original wavelet; the number of decomposition levels is decided by ratio of approximation coefficients standard deviation and detail coefficients standard deviation; the frequency is detected by the new peak search method based on mathematical statistics. The final results show that using wavelet analysis method, vortex signal frequency can be detected almost up to the theoretical low limit of vortex flowmeter.