Lump Circuit Modeling and Matching Consideration on Acoustical Transmitters for Underwater Application

In underwater environment the acoustical wave can transmit a long ranges away from the transmitter than the electromagnetic wave does. So far, the piezoelectric ceramic is still the best candidate as acoustical telemetry transmitters in underwater applications. The impedance matching on the interface between electro-acoustical transducer and electrical transmitter has been the most important subject to confirm the high transmitting efficiency. In this research, a lumped equivalent circuit of electro-acoustic transducer is proposed. Then, the network theorem is implemented to design a high power transformer for impedance matching, and to improve the electro-acoustic efficiency of the transducer. In the developing procedure, the transducer’s impedance is measured and the circuit element of equivalent circuit is deduced from the measured data to correlated the simulated values of the equivalent circuit. Then the matching transformer is developed to meet the specifications of impedance matching and high power operation. The equivalent circuit of the electroacoustic transducer with matching transformer was developed and simulated using Hp-Vee program. The simulated results quite agree with the measured results. This approach really develops an effective method for impedance matching design and reduced the time for trial and error.