Automatic identification of arrival time of acoustic emission signal by means of AR model

The information of acoustic emission (AE) signal's arrival time is very important for event location, event identification and source mechanism analysis. In practical, engineering, the manual picking and amplitude threshold setting up are routinely used to determine the arrival time of acoustic emission signal. To improve the defect of commonly used method, the first arrival time of AE signal was automatically determined through combining AR model of the noise with the acoustic emission signal based on Akaike's information criterion (AIC). The results show that the proposed method is more sensitive to the change of amplitude-frequency characteristics in contrast to the amplitude threshold method. In case the signal-to-noise ratio (SNR) takes the same value, the error of the approach is less than that of threshold detection. Especially, when the SNR is so law that the detection by use of threshold will be no longer effective, the results of the approach are still of enough accuracy.