Fiber-optic perimeter location system based on wavelet transformation

In order to improve the location accuracy of dual Mach-Zehnder interferometic based fiber-optic perimeter location system, the influence of signal frequency range and signal noise ratio (SRN) was analyzed and emulated. Basing on these, a fiber cable, which combines the high-sensitivity to vibration and the adaptability to complex environment, was adopted to ensure the reliability and extend the signal frequency range. The wavelet de-noising algorithm was employed to extract the effective frequency component, filter the noise and advance the SNR. Finally, a field test with 31 km monitoring length was carried out to justify the excellent performance of the proposed fiber cable and the effectiveness of the wavelet de-noising algorithm.