50-km single-ended spontaneous-Brillouin-based distributed-temperature sensor exploiting pulsed Raman amplification.

We demonstrate enhanced performance of a single-ended spontaneous-Brillouin-intensity-based distributed-temperature sensor with a sensing length of 50 km and a spatial resolution of 15 m by use of Raman amplification of the probe pulse within the sensing fiber. The Raman amplification was achieved with a copropagating pump pulse at 1450 nm. The standard deviation error of the temperature resolution was 1 degree C at the front end and increased to less than 13 degrees C at 50 km with Raman pulse amplification.