The Design of Broadband Ultrasonic Transducers for Fish Species Identification - Control of the Resonance Frequency of a Piezoelectric Transducer with Two Pair of Electodes -

어종식별을 위한 광대역 초음파 변환기의 설계 -I - 전극분할형 압전진동자의 주파수특성 제어 -

  • Published : 1997.09.01

Abstract

A method for designing a broadband transducer was investigated experimentally. Control of the resonance frequency of a Piezoelectric circular transducer with two pairs of electrodes was achieved by varying the inductance of external coil connected across the terminal of one pair of electrodes of transducer. The conductance curves of transducer in water were obtained as a function of the inductance value in mH of the coil used in the tuning. As the tuning inductance is increased in value, the resonance frequency is reduced toward the fundamental frequency of 50 kHz. This interesting result suggest that it is possible to produce a continuously tunable transducer covering a frequency range between 61.3 kHz and 121.7 kHz by varying the inductance value of external coil from 2.7 mH to 15.0 mH. One of other problems in the design and construction of such broadband transducer is the transducer efficiency, but this will be the subject of our future work.

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References

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