Analysis of the Pressure Phase Sensitivity Response of the Air-backed Mandrel Fiber-optic Hydrophone

A structural model of a air-backed fiber-optic hydrophone is proposed and the response of the pressure phase sensitivity is investigated.The interaction relation between optical fiber and elastic tube is gained by the acoustic analyses of the principle and basic structure of the air-backed mandrel hydrophone.Then the equivalent model of the dynamics,the theoretical model of the pressure phase sensitivity and dynamic response model of the fiber-optic mandrel hydrophone are obtained.Also based on the finite element method(FEM),the response model of the hydrophone is proposed.According to the structure which is proposed,the mandrel fiber-optic hydrophone is produced with determined parameters.The pressure phase sensitivity and the 3dB bandwidth achieve about 30 kHz in the test,so the results validate our theory model and the FEM model.