BOTDA Sensing Employing a Modified Brillouin Fiber Laser Probe Source

A theoretical and experimental study has been carried out on a tunable dual pump-probe optical source for distributed Brillouin optical time-domain analysis (BOTDA). The developed source exploits a modified Brillouin ring laser technology and is capable of a tuning range of similar to 200 MHz without using phase-locked loop or optical sideband generation techniques, and exhibits a linewidth smaller than 2.5 MHz and similar to 0.5 mW power. In BOTDA experiments, the proposed source has demonstrated to be an efficient solution enabling distributed sensing over 10 km single mode fiber with a spatial resolution of similar to 4 m, and a strain and temperature resolutions of similar to 10 mu epsilon and similar to 0.5 degrees C respectively.