Correction of hydrophone sensitivity variation caused by cable extension based on complex impedance method
Guo Xi-yan · Shengxue jishu · 2014
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.