复数阻抗法修正电缆引起的水听器灵敏度变化

压电式水听器的灵敏度会因为外接电缆的电容效应而降低,在校准和使用中需要根据延长电缆的特性对灵敏度进行修正。从水听器与外接电缆的等效电路出发,推导了复数阻抗法修正水听器灵敏度的方法。以RHS-30和RHS-10水听器为例,由水听器的复数阻抗、延长电缆的开路和短路复数阻抗计算得到了电缆引入的灵敏度修正值,并与实际测得的加电缆前后水听器灵敏度变化值做了比较,结果证明利用复数阻抗法能准确地修正因延长电缆引起的水听器灵敏度变化,与传统的纯电容修正相比,该方法具有更好的适用性。

Correction of hydrophone sensitivity variation caused by cable extension based on complex impedance method

The sensitivity of the piezoelectric hydrophone will decrease because of the capacitive effect caused by cable extension. Sensitivity correction is needed in accordance with the characteristics of the cable extension. This paper starts from the equivalent circuit of the external cable and hydrophone to derive the complex impedance method for the correction of hydrophone sensitivity. Taking the RHS-30 and RHS-10 hydrophone as example, the correction value is calculated from the complex impedance of the hydrophone, the open and short circuit complex impedances of the extended cable, and then, compared with the directly measured sensitivity of the hydrophone with and without cable. The results show that the calculated value is in agreement with the measured value very well. Compared with the traditional method of pure capacitance correction, the complex impedance method is more accurate and could be used in whole bandwidth.