<title>Improving the temperature resolution and response speed of distributed optical fiber temperature sensor with wavelet</title>

Abstract

Distributed optical fiber temperature sensor system can sense the temperature changes along the optical fiber by the continuous form of distance. For the characteristics of insulation and resistance to electromagnetic interference, it has a wide using prospect in the field of petroleum and gas pipeline, tunnel and mine. The distributed temperature measurement is realized by using single channel anti-Stokes light, and the temperature and space resolution of the system can be assured. But the anti-Stokes signal will be submerged by noise because of the weakness of anti-Stokes light signal, the loss of scattering light and the system noise. In order to reduce the influence of various noises in distributed temperature measurement, the method of increasing the times of signal accumulating is used to increase temperature resolution. But this will lengthen the period of temperature measurement and influence the practical application of the system. By using the multi-resolution analysis of Wavelet to handle the distributed temperature signal, we can shorten the period of temperature measurement and enhance the response speed of system on the basis of the assurance of time and space resolutions.