High-frequency plane piezoelectric transducer for high-sensitivity acoustics

With the continuous deepening of ocean exploration and the growth of emergency rescue needs, the hydroacoustic transducer, as an important component of sonar, has become more and more demanding. To improve the reception performance of the piezoelectric transducer, we developed a high-frequency, high-sensitivity planar piezoelectric transducer. A variant 1-3-2 type piezoelectric material is used to improve the effective electromechanical coupling coefficient, the upper surface of the material is covered with a brass plate to amplify the reception stress, and two variant 1-3-2 type piezoelectric materials with different dimensional parameters are arranged vertically to expand the bandwidth. We investigated the material properties and determined the material dimensions actually used to fabricate a planar hydroacoustic transducer utilizing electromechanical equivalent circuit analysis methods and finite element simulations. A prototype planar hydroacoustic transducer was fabricated and tested for resonant frequency, receiver sensitivity, bandwidth, and horizontal directivity then. The results show that the transducer's resonant frequency is about 218.7 kHz, the maximum receiving sensitivity is -178:7 dB, the 3 dB loss receiving bandwidth is about 45 kHz, and the horizontal directivity is about 17°. The test results all indicate that the developed hydroacoustic transducer has great potential for application in marine exploration and underwater emergency rescue.