Investigation on the working point of slope-assisted dynamic Brillouin distributed fiber sensing

Abstract

In this paper, an investigation on the working point of slope-assisted dynamic distributed Brillouin sensing is presented. A comparison has been carried out between the sensing performances achieved at the inflection point and the 3 dB point of the Brillouin gain spectrum. Besides the intrinsic 13.1% frequency-to-amplitude sensitivity enhancement and a higher signal level, the dynamic sensing at the inflection point can achieve a doubled in maximum and in average a 36.8% wider dynamic range with much better working point symmetry. Simulations with strain signals also demonstrate that, compared to the 3 dB point, the average error at the inflection point can be significantly reduced to only 27.7%. As shown in this work, by a simple shift of the working point from the 3 dB to the inflection point, slope-assisted dynamic sensing can be well enhanced.