Spatial resolution is an important parameter in distributed optical fiber Raman temperature sensor system (DOFRTS). In this paper, a 10 kilometers long DOFRTS with spatial resolution of about 6 meters is constructed. The spatial resolution is limited by electrical bandwidth of the photodetector circuit and the data acquisition part. The abrupt temperature changes along the fiber axis are treated as temporal pulse signals, and a linear amplitude coefficient modification algorithm is used to improve the spatial resolution. The experimental results show that the temperature amplitudes from 3 meters region to 6 meters can be modified accurately. Therefore, a DOFRTS of high spatial resolution but low system cost could be successfully constructed.
Cryogenic-temperature profiling of high-power superconducting lines using local and distributed optical-fiber sensors