1’000’000 resolved points along a Brillouin distributed fibre sensor

The challenge to resolve a record of one million points along a single optical fibre is demonstrated using a Brillouin distributed fibre sensor. The proposed system is based on a phase-correlation technique combined with a temporal pump gating, making possible to detect a 14 mm-long hot-spot located at the end of a 17.5 km-long fibre. This corresponds to an increase by one order of magnitude in the number of points that a single system has resolved, representing a major breakthrough in the field. Specific issues arising when resolving such a large number of points are discussed.