Method for Identifying Mechanical Vibration Source Based on Detected Signals by Optical Fiber

A Optical Fiber Vibration pre-Warning System (OFVWS) has an ability to detect and identify vibration signals by using a optical fiber cable lain along with pipes, hence it has been widely applied in some safety fields, such as the pipeline transportation, national defense, military base and so on. In the application of the OFVWS, one of the key issues is to identify harmful mechanical vibration sources quickly and efficiently. In this paper, we analyzed vibration signal produced by mechanical vibration sources and extracted the signal features transmitted by the OFVWS. A conclusion was drawn that most of mechanical vibration sources have an obvious feature of fundamental frequency. Based on this conclusion, we developed a method to detecting and recognizing a mechanical vibration source based on a variation coefficient of fundamental frequency periods. This method is able to accurately judge if the detected vibration signals having a feature of fundamental frequency or not by calculating and analyzing its variation coefficient of fundamental frequency periods. Field test results showed that this method can identify various harmful mechanical vibration sources, and have a high probability of detection and recognition, and a low probability of false alarm. Copyright © 2013 IFSA.