Fiber microphone based on distributed acoustic sensing

A theoretical model combined with finite element simulation and numerical analysis is presented to design and optimize of the fiber-wrapped mandrel optic microphone based on distributed acoustic sensing (DAS). To increase the acoustic pressure sensitivity, the optimized fiber-wrapped mandrel microphone with engraved uniform grooves is fabricated and tested as the acoustic transducer. The average sensitivity is -136.915dB re:1rad/mu Pa between 50 Hz to 2450Hz, which is 25.306dB higher than the same fiber optic microphone without uniform grooves. The experimental results are in good agreement with the theoretical results, which shows this theoretical approach is effective to design and optimize the fiber-wrapped mandrel optic microphone based on DAS.