Experimental Research of 30 km Long Distance Distributed Optical Fiber Raman Temperature Sensor System

A 30 km long range distributed optical fiber Raman temperature sensor (DOFRTS) system has been made, it use new measuring temperature principle of optical fiber amplified anti Stokes Raman spontaneous scattering. In the system, 1550 nm erbium doped optical fiber laser, high speed data acquisition card and signal processing technique are used. By using these technique, the problem of weak signal detection is resolved and signal to noise ratio is increased. All components of system are put into an intellectualized constant temperature box and work in constant temperature condition. Stability and environment adaptability are improved. By appraisal, performance of the system is listed as follows: optical single mode fiber: 31 km, temperature rang: 0～100℃ (can be expanded), temperature measuring uncertainty: ±2℃, temperature resolution: 0.1℃, measurement time: 432 s, spatial resolution: 4 m. The contrast table of the performance of DOFRTS system is given in the paper.