title: System optimization of a long-range Brillouin-loss-based distributed fiber sensor.
abstract: We report a high-performance 25 km Brillouin-loss-based distributed fiber sensor through optimizing system parameters. First, the Brillouin spectrum distortion and measurement error induced by the excess amplification on probe pulse are investigated, and the results indicate that a low continuous-wave pump power is essential to decrease the measurement error. Then an optimal pulse pair is determined through the differential Brillouin gain evolution along the entire sensing fiber in a differential pulse-width pair Brillouin optical time domain analysis. Using dispersion-shifted fiber to allow a high-power probe pulse, we realize a 25 km sensing range with a spatial resolution of 30 cm and a strain accuracy of ±20 με, which we believe is the best performance in such a length, to the best of our knowledge.
authors.affiliation: Fiber Optics Group, Department of Physics, University of Ottawa, Ottawa, Canada, K1N 6N5. aldendong@gmail.com
authors.forename: Yongkang
authors.initials: Y
authors.lastname: Dong
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Bao