Measurement Range Enlargement in Brillouin Optical Correlation Domain Analysis Using Multiple Correlation Peaks
نویسندگان
چکیده
So far, Brillouin scattering based sensors have been studied as promising technology for a distributed temperature or strain measurement in structural health monitoring [1-10]. Intrinsically, Brillouin scattering is an effect caused by acoustic vibrations in the medium when laser light travels in a medium such as an optical fiber. Since the sound wave is traveling, light is also subjected to a Doppler shift, so its frequency changes. The Brillouin frequency shift ν B can be calculated from the effective refractive index of the propagating media n, the acoustic velocity Va, and the wavelength of the incident light λ :
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