The Research of Improvements in Raman Distributed Temperature Sensor

Temperature measurement system has been applied in industrial areas extensively. The fiber optic distributed temperature system is one of the most popular means. Measurement error is relatively large when using the distributed temperature sensors (DTS) based on Raman scattering to measure ambient temperature in harsh environments. In this paper, we propose a novel calibration technique to measure the temperature highly accurately over a wide range of temperatures. We also propose an improved double-ended configuration that is insusceptible to the differential loss change in the fiber. By using the improved double-ended configuration, through the anti-Stokes and Stokes signal intensity comparison, the differential mode signal loss in the temperature measurement can be suppressed in optical fiber. So, the measurement results of automatic calibration are irrespectively with the wastage of optical fiber sensors. The result shows that we can obtain the temperature parameters accuracy in wide temperature range, and temperature measurement system has high robustness in harsh environments, suitable for field use.