At present, the demand for perimeter security system is increasing greatly, especially for such system based on distributed optical fiber sensing. This paper proposes a perimeter security monitoring system based on phase⁃sensitive coherent optical time domain reflectometry(Ф⁃COTDR) with the practical pattern recognition function. We use fast Fourier transform (FFT) to exact features from intrusion events and a multi⁃class classification algorithm derived from support vector machine (SVM) to work as a pattern recognition technique. Five different types of events are classified by using a classification algorithm based on SVM through a three⁃dimensional feature vector. Moreover, the identification results of the pattern recognition system show that an identification accurate rate of 92.62% on average can be achieved.
fiber optics sensors; COTDR; distributed vibration sensing; SVM; pattern recognition