Signal processing of FBG vibration sensor based on duffing oscillator model

Abstract

In this paper, one fiber Bragg grating (FBG) vibration sensor is proposed and the application of weak signal processing based on Duffing oscillator model in optical fiber vibration sensors is studied. Frequency response and amplitude sensitivity experiments are all carried out to verify the characteristics of this FBG vibration sensor. By calculating the maximum Lyapunov exponent, these experiment data are analyzed. The result confirms that this FBG vibration sensor has excellent frequency response ability. When signal to noise ratio (SNR) −3.2 dB of the original signals is too small, FFT could not extract frequency information from the original signals, correctly. However, weak signal processing method studied in this paper could effectively obtain the vibration measurement coefficient under the same conditions and its value is 2.27 pm/(m/s2).