Fiber Optic Raman Distributed Temperature Sensor Based on an Ultrashort Pulse Mode-Locked Fiber Laser

The testing of an all-fiber erbium ultrashort pulsed laser in a distributed fiber temperature sensor as a source of probing pulses has been performed. Among the prospects of such an approach are an improved signal–noise ratio in the receiving system and a better spatial resolution of the temperature sensor. The experiments have revealed the factors that limit the effective length of the fiber temperature sensor, such as a high pulse repetition frequency and intrinsic laser noises. As a result of the performed work, the distributed fiber optical temperature sensor with a near-room-temperature resolution of ~1.5 K, an effective length of ~3 m, and a spatial resolution of ~10 cm has been developed.