Going beyond 1000000 resolved points in a Brillouin distributed fiber sensor: theoretical analysis and experimental demonstration

摘要

A distributed fiber sensor has been developed that can resolve more than 2 million points along its length. The system, built by Andrey Denisov and co-workers from École Polytechnique Fédérale de Lausanne, offers a spatial resolution of just 8.3 mm over a distance of 17.5 km. This has been achieved by combining phase-modulation correlation-domain analysis with temporal gating of the pump signal and a theoretical model to optimize the signal-to-noise ratio. The measurement time varies cubically with the number of sample points. Consequently, a measurement of 300 000 points corresponding to a resolution of 5 cm takes only 4 min. Thus, the researchers say that a coarse scan of the whole fiber can be quickly made prior to a finer resolution scan of the region of interest.