Diaphragm resonance-based fiber optic hydrophone

摘要

Passive hydrophones with a minimal footprint are useful for a variety of underwater monitoring applications; a fiber optic hydrophone is being investigated. Fiber optic hydrophones have been used in offshore moored applications, and have the capability to cover large areas. A resonant hydrophone using a fiber Bragg grating (FBG) transducer for limited bandwidth operation is described and compared with predicted diaphragm resonances. A battery-power readout system using a laser diode source that can typically operate for a full day, and can be used in off-mooring applications such as in autonomous underwater vehicles, is outlined.