2Ã\x972 juxtaposed Type Optical Fiber Raman Temperature Sensor

We report on a 2×2 juxtaposed type optical fiber Raman temperature Sensor. Two output ports of the 2×2 couple make coupling of the optical fiber respectively and two optical fiber made fascis will be a item of the sensor optical fiber. On the condition that the quasi-continuous wave inputs, the couple has the nonlinear switch theory, hence the signals received by the detector will take four times of what a single sensor optical fiber does. A new demodulated method for the simultaneous distributed temperature measurement in an optical fiber based on spatially resolving the Ant-Stokes signals of the spontaneous Raman back-scattering, the sensitivity of sensor is heightened. We make up the experimental system and achieve 5km of length, 1m of distance resolution, accuracy to ±0.1°C.