Identification of Effective Events Recorded by Optical Fiber Microseismic Monitoring System

Abstract

Abstract At present, the development of microseismic monitoring system based on electronic sensors is restricted by the problems of power supply, electromagnetic interference and etc. How to select effective microseismic events from the massive and uninterrupted raw data is also a huge problem. In this paper, the DFB laser is used to demodulate the external vibration signal detected by the FBG sensor. The first arrival time of the P wave and the end point of the signal are picked up by using the improved STA/LTA algorithm. The method of calculating the optimal time window width is established by using the characteristics of periodic vibration wave. The criterion of the effective signal is established by using the maximum energy ratio of the effective signal. The resolution of this demodulation method is 0.01 pm. The criterion of effective signal discrimination can be used to accurately determine whether a channel event belongs to an effective signal or a noise signal. The microseismic monitoring system based on optical fiber sensor meets the needs of monitoring in a harsh mine environment, and the effective event discrimination criterion based on signal deviation is feasible.