Research On Distributed Optical Fiber Temperature And Strain Sensing Technology Based On Brillouin Scattering

The state of the art of distributed optical fiber sensing technology has been introduced with particular attention to the distributed sensing based on Brillouin scattering. The temperature and strain dependences of Brillouin shift and intensity have been investigated theoretically, and the achieved temperature and strain coefficients of Brillouin shift and intensity accord very well with the reported experimental results. The methods for calculating the performances of Brillouin sensing system such as signal to noise ratio, spatial resolution, measurement time et al. has been studied. A system capable of realizing temperature and strain sensing with high spatial resolution and high accuracy has been designed and the performances of the system has been evaluated. An experiment system for Brillouin spectrum measurement has been setup. Brillouin spectra of the seawater-corrosion resistant carbon-coated fiber, high-temperature resistant fiber and G.652, G.655 communication fiber at room temperature have been measured, and the qualitative measurement of temperature and strain dependences of Brillouin spectrum in G.652 optical fiber has been also accomplished..