An Ultrahigh Resolution FBG Dynamic Strain Sensing System with Eigenvector Spectrum Analysis Method

摘要

An in-fiber Bragg grating (FBG) dynamic strain sensing system based on a fiber ring laser configuration and the Eigenvector spectrum analysis method, is proposed and demonstrated. An ultrahigh dynamic strain resolution of 5×10~(-5) ne /Hz~(1/2) is achieved due to both the use of the supper white-noise suppression ability of the advanced spectrum analysis method and the high optical signal-to-noise ratio (SNR) (~65dB) of the sensing signal generated by the fiber ring laser scheme. This is the highest dynamic strain resolution achieved so far for a single FBG sensor at frequency of <100Hz, to the best of our knowledge.