Proposal and verification of sensitivity calibration methods for miniature hydrophones in the high frequency range

微型水听器高频灵敏度校准方法的提出与验证

• 批准号: 10650404
• 负责人: KAMAKURA Tomoo
• 金额: $ 2.24万
• 依托单位: The University of Electro-Communications
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650404/
• 关键词: hydrophone; reciprocity calibration; nonlinear acoustics; waveform distortion; harmonics; 校正

Two different kinds of miniature PVDF hydrophones of 0.6mm and 1mm in diameter have been calibrated for their sensitivity responses using two methods. One of which is based on a conventional methodology, the reciprocity calibration, and the other is based on nonlinear propagation of sound beams. Specifically, ultrasound beams of finite amplitude generate waveform distortions due to the inherent nonlinearity of a medium, and plenty of harmonics appear significantly in the beam. The magnitudes of individual harmonic components are theoretically predicted by a model equation that we propose for precise description of nonlinear sound beams. The harmonic pressures are strongly dependent on source conditions such as driving frequency and source pressure level. The sensitivity response of output voltage to pressure at the fundamental frequency is measured by the reciprocity method. The information of the fundamental frequency source conditions uniquely determines all the pressure magnitudes of higher harmonics. By detailed comparison of harmonic pressures between experiment and theory, the calibration in the frequency range of 2.5 to 20MHz has been performed for the two different hydrophones. It has been concluded that the sensitivity responses for the hydrophones are overall in good agreement with the attached data sheets within 1.5dB differences.

用两种方法对直径分别为0.6mm和1 mm的两种不同的小型PVDF水听器的灵敏度响应进行了标定。其中之一是基于传统的方法，互易校准，和其他的是基于声束的非线性传播。具体而言，由于介质的固有非线性，有限振幅的超声波束产生波形失真，并且在波束中显著地出现大量谐波。理论上预测的模型方程，我们提出精确描述的非线性声束的各个谐波分量的幅度。谐波压力强烈地依赖于源条件，例如驱动频率和源压力水平。用互易法测量了输出电压在基频处对压力的灵敏度响应。基频源条件的信息唯一地确定了所有高次谐波的压力幅值。通过对实验和理论的谐波声压的详细比较，在2.5 ~ 20 MHz的频率范围内对两种不同的水听器进行了校准。得出的结论是，水听器的灵敏度响应总体上与所附数据表一致，差异在1.5dB以内。

项目成果

Tomoo Kamakura: "A theoretical approach to the analysis of nonlinear sound beams using the oblate spheroidal coordinate systems"J. Acount. Soc. Am.. 105 (6). 3083-3086 (1999)

Tomoo Kamakura：“使用扁球坐标系分析非线性声束的理论方法”J。

T.Kamakura et al.: "A new theoretical approach to the analysis of ncnlinear sound beams using the oblate spheroidal coordirate system" J.Accust.Soc.Amer.(in press). (1999)

T.Kamakura 等人：“使用扁球坐标系分析非线性声束的新理论方法”J.Accust.Soc.Amer.（出版中）。

Tomoo Kamakura et al.: "A theoretical approach to the analysis of nonlinear sound beams using the oblate spheroidal coordinate system"J. Acoust. Soc. Am.. 105(6). 3083-3086 (1999)

Tomoo Kamakura 等人：“使用扁球坐标系分析非线性声束的理论方法”J.

Tomoo Kamakura: "A theoretical approach to the analysis of nonlinear sound beams using the oblate spheroidal coordinate system"J. Acoust. Soc. Am.. 105(6). 3083-3086 (1999)

Tomoo Kamakura：“使用扁球坐标系分析非线性声束的理论方法”J。