Method for identifying arrival time of acoustic emission signal based on de-noising processing

Signal arrival time is vital information in the research of rock acoustic emission source TDOA location. Rock acoustic emission signal is complex and contains a lot of pulse interferences and random noises. Its arrival time is of poor readability. The method of traditional manual identification is time-consuming, for instance, the threshold method presents low accuracy, and AR-AIC method's precision would decrease if SNR is low. To solve the problems mentioned above, firstly, part of the pulse interferences and random noises in original acoustic emission signals were eliminated by median filter and singular value decomposition. Secondly, the main components of the signals were retained to improve SNR and enhance the readability of arrival time by wavelet packet decomposition soft threshold de-noising. Finally, arrival time was identified in the gained time window through combining with the AR model of signals and noises by calculating AIC(K) twice. ©, 2015, China Coal Society. All right reserved.