Abstract

In this work, a distributed hydrostatic pressure sensor based on Brillouin dynamic gratings (BDGs) was proposed and demonstrated for the first time to the best of our knowledge. The hydrostatic pressure sensing is realized through measuring the pressure-induced birefringence changes through exciting and probing the BDGs; while the temperature can be compensated by measuring the temperature-induced Brillouin frequency shift (BFS) through differential pulsewidth pair Brillouin optical time-domain analysis (DPP-BOTDA). The thin-diameter high-birefringent PM-PCF is used as the fiber under test and its porous-structure cladding is liable to be deformed exhibiting a high sensitivity to pressure. A distributed measurement with a 20-cm spatial resolution and a measurement accuracy as high as 0.025 MPa is reported.

© 2016 Optical Society of America