Research on Signal Propagation Model of Buried Pipe Fiber Vibration Monitoring System

Abstract The signal processing methods related to Ф-OTDR fiber monitoring system are unable to analyze the signal characteristics in terms of signal generation and propagation. These models lack the correspondence between the disturbance event parameters and the fiber structure parameters and cannot quantify the characteristics. Moreover, the signal processing methods are not targeted, and the accuracy of pattern recognition is low. In this work, we establish a complete theoretical model for the intrusion signal propagation process of the buried pipeline Ф-OTDR optical fiber monitoring system. The proposed model takes the signal generation, propagation in the medium to the optical fiber, and the entire process of the variations in light intensity in the optical fiber into consideration. The accuracy of the proposed model is verified by comparing the acquired field vibrations with simulation results. The results presented in this work provide a complete theoretical framework for the signal analysis and processing methods of the Ф-OTDR optical fiber monitoring system. Moreover, it also provides ideas for the study of pattern recognition algorithms.