Experimental Study on Brillouin Optical Fiber Temperature Distributed Sensing System

Based on a temperature measurement principle of Brillouin optical time-domain fiber sensor, an optical fiber temperature distributed sensing system was established. Brillouin frequency shift temperature coefficient of the system is calibrated by measuring the Brillouin frequency shift spectrums of the optical sensing fiber to determine the peak Brillouin frequency shift at different temperatures. With the system temperature coefficient, system experiments on measuring the temperature of 900m optical fiber were carried out. Experimental results show that temperature changes on the sensing optical fiber can be sensitively sensed in the system. And relative errors of these measurements are between 0.017% and 0.279%.