Research On The Miniaturization Of Tri-axial Piezoelectric Vector Hydrophone

Vector sensors used in many application areas such as buoys and towed sonar array are required to be reduced in size, so the miniaturization of vector sensor is necessary to promote the performance of these systems.In this paper, the miniaturization of a kind of typical tri-axial piezoelectric vector hydrophone was researched.The sensor adopts a new structure of sharing one block of mass, and has significantly reduced the size and is completely symmetrical in structure. With the analyze of the theory of piezoelectric accelerometer and resonant-sphere vector hydrophone, and the simulation function of Ansys, the size of tri-axial accelerometer has been finally determined. It make the relevant vector hydrophone of a smaller size have a higher sensitivity during a wider range of frequency. Then a integrative tri-axial accelerometer working from 20Hz to 1 000Hz has been produced manually, and calibrated by the vibration test system of B&K3629. The result of the test shows that the average sensitivity of the sensor achieves 11450 pC/g.Then the accelerometer designed was fixed in a vector hydrophone which combined a vector sensor with a pressure hydrophone. The performance of the vector hydrophone which diameter is 130mm was tested in the standing wave field between 20~1000Hz.The average sensitivity of vector channel reached -179dB (0dB = 1V/μPa, 1000Hz) ,and the pressure sensitivity of pressure channel was -203dB.The research made the miniaturization of vector hydrophone under the same request possible.