Fiber optic acoustic sensor based on Fiber Bragg grating Fabry-Perot(FBG-FP)cavity

An acoustic sensor based on Fiber Bragg grating and Fabry Perot (FBG-FP) cavity is introduced in this paper. In the low frequency (20 Hz) field, the sensitivity reaches 0.43 V/Pa. In the intermediate frequency range of 700 Hz-2 kHz, it has relatively flat frequency response characteristics, and the sensitivity is 28.2 mV/Pa. The signal-to-noise can reach 53.1 dB (100 Hz), and the minimum detection sound pressure is 2.52 mPa/Hz1/2.