A fully distributed simultaneous strain and temperature sensor using spontaneous Brillouin backscatter

We report here the first simultaneous measurement of strain and temperature using Brillouin backscatter in an optical fiber. A new sensor arrangement is presented which allows the distributed measurement of Brillouin spectra. Simultaneous measurement of spontaneous Brillouin power and Brillouin shift distributions are made from these spectra, and from this information, we obtain fully distributed measurements of strain and temperature. Our sensor achieves a 100-μ/spl epsiv/ strain and 4/spl deg/C temperature resolution, with 40-m spatial resolution, over a sensing length of 1200 m.