An Brillouin backscattered power a measure for sensing strain in civil structures due to displacement of optical fiber
In this paper the application of Brillouin Scattering for monitoring strain along the fiber is carried out by designing a strain sensor. Inside the fiber the photons interact with the fiber molecules and cause some changes in the propagation of light. The backscattered light spectrum contains three types of light signal namely; the Rayleigh backscattered light, the Brillouin backscattered light and the Raman backscattered light. The backscattered optical signals carries much information on the variation of strain in the path of wave propagation. The Brillouin backscattered light signal power can be used to obtain information about the strain distribution along the fiber. The changes in Brillouin backscattered light signal is effective in detecting the strain changes in the surrounding. In this paper the application of Brillouin Scattering for strain monitoring is performed. Detailed designing of a strain sensor for application in civil structures is done to validate the proposed method using the OptiSystem software.
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