The Research of Raman Type Distributed Optical Fiber Temperature Measuring Method

WT5”BZ]:The principle of Raman scattering type distributed optical fiber temperature measuring method has been researched,and four demodulation methods using single channel and double channels have been discussed.The expression of relative temperature sensitivity S a,S s,S a/s and S a/R of four demodulation methods have been put forward and the values are 1.065 %·K -1 ,0.104 %·K -1 ,0.862 %·K -1 and 1.065 %·K -1 respectively in the 0～120 ℃ region.Because of the “cross talk” of wavelength division multiplexer,the relative temperature sensitivity of practical system is lower than the theoretical value. [WT5”HZ]