The simultaneous measurement of strain and temperature distributions from Brillouin backscatter

The strain dependence of the optical power for Brillouin scattering in optical fibres has been measured for the fast time. Together with measurements of the dependence of Brillouin power on temperature and the variation of Brillouin frequency with temperature and strain we demonstrate viability far a simultaneous temperature and strain sensor based on spontaneous Brillouin scattering. We report the first simultaneous distributed strain and temperature sensor based on this idea. The sensor achieves a 100 με strain and 4°C temperature resolution, with 40 m spatial resolution, over a sensing length of 1200 m