Strain measurement in multimode fibers using Brillouin optical time-domain reflectometry

Summary form only given. In summary, a Brillouin optical time domain reflectometer (BOTDR) has been demonstrated, for the first time to our knowledge, as useful in evaluating, distributed strain in multimode fibers. The Brillouin frequency shift was not sensitive to small differences in modal excitation. Changes in average fiber strain measured using this method and the phase-shift technique were shown to be in agreement. Differences in cabled longitudinal fiber strain due to differing thermal responses of buffer material and the cable reel have been demonstrated.