Method of on-line resistance and capacitance measurement of piezoelectric ceramic hydrophones

Piezoelectric ceramic hydrophone is an important unit to modern acoustic equipments. On-line resistance and capacitance measurement should be provided in order to achieve better working quality and easily maintaining because acoustic cables are made up of many sealed hydrophones. But traditional measurement is so complex that it is difficult to achieve smaller structure and low cost. Based on the theory of circuit, the front-end equivalent circuit model of hydrophone is given and analyzed. The analytic expression is deduced based on this model. Furthermore, it is pointed out how to choose the parameters of measurement circuit. At last, a realized measurement circuit is given. It has a clear concept, simple structure, low cost, and it can measure accurately and quickly. It has been proved to be correct and effective by testing of the measure circuit. The result means that the traditional method of measure can be replaced by this one.