Abstract:

The temperature effects of Raman and Rayleigh light in the distributed optical fiber temperature sensor system are mainly discussed. The analysis shows that the anti Stokes light temperature sensitivity is much higher than Stokes light and it is why all such sensor systems generally use it for temperature information. Then, two demodulation methods are theoretically analyzed in detail by comparing their system temperature sensitivities. Finally, an algorithm is proposed according to the loss of the sensing optical fiber, which is necessary to an actual sensor system. Application practice has indicated that all the above conclusions are correct and reasonable.

Key words: Raman scat tering, Rayleigh scat tering, temperature op t ical fiber, demodulat ion