Measurement range elongation based on a temporal gating scheme in Brillouin correlation domain distributed discrimination system for strain and temperature operated by a single laser

摘要

We have demonstrated distributed discrimination of strain and temperature by localizing and scanning both the Stimulated Brillouin scattering (SBS) and the Brillouin dynamic grating (BDG) along a polarization maintaining fiber, with elongated measurement range. The localization and scanning is performed by a correlation domain technique, whose measurement range is restricted by the distance between consecutive correlation peaks. To overcome this restriction, we applied a temporal gating scheme to the system, enlarging the measurement range from ~8 m to ~500 m. Here, we report the results confirming the effectiveness of this scheme in a system operated by a single laser source and demonstrate strain-temperature discrimination when strain or temperature is applied to segments on the 500-m-long fiber under test.