Package improvements and testing of a novel MEMS bionic vector hydrophone

For self-noise reduction of underwater targets, low-frequency detection vector hydrophone is necessary in underwater passive detection. A novel MEMS vector hydrophone with bionics structure is introduced in this paper. The sensing principle of this vector hydrophone is based on the acoustic theory of cylinder utilizing piezoresistive effect. Preliminary performance of the vector hydrophone was obtained in 2007. Now the parameter of the sensitive cell has been optimized, and the package is improved. All these researches are presented in this paper. Besides calibration is completed, the results show that the sensitivity of vector hydrophone can achieve -165 dB (conditioning by preamplifier) at the frequency from 20 Hz to 2 kHz. The experiments of vector hydrophone applied in the acoustic source direction estimation are also presented. The test value agrees well with the actual value and the error is within 1°.