In this work an experimental development of a distributed Brillouin sensor in optical fiber, for strain and temperature detection in civil infrastructures, is presented. With this configuration it is possible to get 5 m of spatial resolution and the possibility of sensing up to 50 km of standard optical fiber with an acceptable contrast. Investigation of a method to extend-range distributed temperature and strain sensor based on detection of the Brillouin frequency shift combined with counter-propagating Raman amplification has been realized. 50-km-range of standard-single-mode silica fiber (SSMF) has been sensed with a greater signal contrast.

Peer reviewed