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arXiv · 2302.07065

120 km single-photon Brillouin optical time domain reflectometry

Maxime Romanet·Luis Miguel Giraldo·Maxime Zerbib·Etienne Rochat·Kien Phan Huy·Jean-Charles Beugnot
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Abstract

We present a novel distributed Brillouin optical time domain reflectometer (BOTDR) using standard telecommunication fibers based on single-photon avalanche diodes (SPADs) in gated mode, hd-BOTDR, with a range of 120 km and 10 m spatial resolution. We experimentally demonstrate the ability to perform a distributed temperature measurement, by detecting a hot spot at 100 km. Instead of using a frequency scan like conventional BOTDR, we use a frequency discriminator based on the slope of a fiber Bragg grating (FBG) to convert the count rate of the SPAD into a frequency shift. A procedure to take into account the FBG drift during the acquisition and perform sensitive and reliable distributed measurements is described. We also present the possibility to differentiate strain and temperature.

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Maxime Romanet, Luis Miguel Giraldo, Maxime Zerbib, Etienne Rochat, Kien Phan Huy, Jean-Charles Beugnot. 2023-02-14. 120 km single-photon Brillouin optical time domain reflectometry. https://doi.org/10.1364/oe.492488

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