| The optical Fiber Bragg Grating hydrophone is a transducer that converts underwater acoustic signal into light signal.It is an important sensor in underwater acoustics.In practical engineering application,the acoustic pressure sensitivity,acceleration resistance performance and hydrostatic pressure resistance of the hydrophone probe are very high.This paper first studies the technology principle of Fiber Bragg Grating hydrophone and the research results of hydrophone probe structure at home and abroad.Secondly,the stress sensing principle,temperature sensing mechanism and stress temperature cross sensitivity characteristics are studied.The paper also analyses and compares various signal demodulation techniques.On this basis,the following main tasks have been completed:(1)The general structure scheme using symmetrical double elastic diaphragm is is proposed.The structure design of hydrophone probe based on casing temperature compensation structure is completed.In the design scheme,the probe structure of elastic diaphragm is used to explore the characteristics of the acoustic pressure sensitivity,acceleration sensitivity,temperature sensitivity,dynamic frequency and so on in the basic theory of elastic mechanics.(2)Completed the the Fiber Bragg Grating hydrophone sample with elastic diaphragm packaging structure,and preliminarily discussed the technology of the probe structure.(3)Completed the test of hydrophone samples.The acoustic pressure phase sensitivity,acceleration resistance,temperature compensation function and withstand voltage performance of the hydrophone sample were tested.The sound pressure sensitivity,vibration sensitivity,temperature compensation characteristics and pressure resistance of hydrophone based on elastic diaphragm packaging structure were tested. |
