THE STUDY OF HIGH-FREQUENCY BROAD-BAND UNDERWATER TRANSDUCERS

There are many advantages of broadband transducers, such as reducing of signal distortion, widening the security about information transmission, reducing the ratio of false codes. The combine of piezoelectric pillars and dual matching layers can expand the bandwidth of the high-frequency transducer. The one-eighth finite element model of transducer was set up with ANSYS software and the structure of the transducer was optimized. A final transducer was designed, which used the first thickness mode, the second thickness mode and the third thickness mode. The bandwidth of the transducer is 47kHz-159kHz, in which the ripple of the transmitting voltage response does not exceed +/- 3dB. There are several conclusions from the research: the bandwidth of pillar transducers can be expanded by the first thickness mode, the second thickness mode and the third thickness mode, and it gives a method to achieve the broad-band projecting performance of high-frequency transducers.