Raman distributed optical fiber temperature measurement system based on scattered light power correction

Aiming at the sensitivity of Raman anti-Stokes scattered light to the temperature, a novel distributed optical fiber temperature measurement system based on automatic power correction algorithm is proposed and experimentally demonstrated. The power automatic correction algorithm is based on corresponding temperature data and power value of the scattering position for temperature calibration. And by the power and temperature conversion relationship of the Raman anti-Stokes scattering light, the measured Raman anti-Stokes optical time domain reflecting trace for temperature demodulation is corrected by the obtained power correction coefficient. Therefore, the influence of unfavorable factors in traditional single-channel and double-channel Raman optical fiber distributed temperature demodulation methods are eliminated, so that the stability and measurement accuracy of the temperature measurement system is improved. The experimental system is set up with multimode fiber (MMF) in a range of about 16.3km, and the experimental results achieved the spatial resolution of 2m and the temperature measurement accuracy of ±1.6℃, and the response time is less than 1.5s, which is of great significance to practical engineering application.