Simulation and Measurement of an Acceleration Sensitivity for a Fiber-optic Vector Hydrophone System

Promoting acceleration sensitivity of three-dimensional fiber-optic inertial vector hydrophone is an important requirement in underwater acoustic sensing. Firstly, numerical calculating and finite element simulating technologies are both used to study the acceleration sensitivity. By simulation, it gets the relationship curve between acceleration sensitivity and sensing frequency, with the work frequency 20Hz-2000Hz and acceleration sensitivity 28.7dB in designing parameters. Secondly, the hydrophone is fabricated with using the designing parameters of the simulation. Finally, a fiber-optic vector hydrophone acceleration sensitivity measurement setup is built, and its acceleration sensitivity is tested. In the measurement, vibration signals can successfully be detected and demodulated, when it shows that work frequency of the hydrophone is 20Hz-2000Hz and its acceleration sensitivity is 30dB, whose deviation is 1.3dB from simulation. Comparing and analyzing the simulation and the measurement on acceleration sensitivity, the structure of the hydrophone is proved to be correct and applicable. It is reference significance for its practical application of a fiber-optic vector hydrophone.