Optical fiber characterization for optimization of a Brillouin-scattering-based fiber optic sensor

Abstract

Brillouin scattering-based distributed fiber optic sensors have been shown to be effective diagnostic tools for monitoring structural health and detecting fires and hot spots, among other uses. Current research has mainly been focused on improving the spatial, strain and temperature resolutions, and sensing lengths of these systems, generally by the use of better signal processing and improved equipment. In contrast, there has been little published work on optimizing the sensing optical fiber itself. A number of commercially available optical fibers have been measured in order to determine how to optimize their Brillouin characteristics. Some characteristics chosen are the number of Brillouin peaks, the frequency of the peaks, their linewidth, and the temperature and strain coefficients of each peak. It is shown that lowering the intrinsic Brillouin frequency of the fiber can increase the Brillouin strain coefficient and decrease the temperature coefficient of the optical fiber for the main Brillouin peak, among other results.

Analysis of Brillouin Scattering Based Fiber Optic Sensor Bonding Effects

“…One method involved the use of optical fiber with multiple-peaked Brillouin spectra. Each spectral peak may have different strain and temperature coefficients, which would allow a system of two equations and two unknowns to be solved for the applied temperature and strain (Lee et al, 2001;Brown et al, 2004;Zou et al, 2004). In order to prove that bonding the optical fiber changes the temperature coefficients for all spectral peaks, further tests were performed.…”

High‐performance Brillouin distributed temperature sensor using Fourier wavelet regularised deconvolution algorithm

“…However, the downside is the receiver complexity. BDS [4, 5] can be implemented using either spontaneous or stimulated Brillouin scattering (SBS) mechanism. The spontaneous‐BDS require a simpler implementation scheme [6].…”