A computerized system for Monitoring and informing about any unauthorized drilling operations near the cables.

Abstract

The biggest challenge is to protect the cables in cities and villages from random excavations, as the protection of these cables by traditional methods such as concrete and some cement stones is not sufficient. It has become necessary to search for effective and alternative protection techniques that can protect the cables. In this paper, a novel method is proposed to design a drill monitoring system for early warning using fiber optic distributed acoustic sensing systems (DAS) based on phase OTDR. The proposed method has three stages. The first stage is to use buried fiber optic cable as a sensing system to detect any activity such as drilling or digging near the cable. The second stage is the processing system; in this stage, the sensed signal is de-noised using a wavelet transform, and then the difference is used for high pass filtering. This phase includes the autocorrelation to improve the interferometric visibility of the movements or threats near the goal area via a fiber optic cable. Moreover, the correlated signal power is computed and sent to the test and comparison stages. In the last stage, all signals are compared with a predefined threshold; if the average exceeds the threshold, the discrete signal is considered to be high, and there is drilling near cables; otherwise, the signals are considered to be undesired signals. Different types of activities were used at different SNR levels to assess the effects of the proposed method on detection performance. The results show the effectiveness of the used system for early drilling detection to protect the cables.