Equivalent Circuit for Broadband

A method is presented to determine the equiva- lent circuits of broadband transducers with 2 resonances in the frequency band of interest. The circuit parameters are refined by least-squares fitting the measured electrical conductance data with this model. The method is illustrated by computing the conductance and susceptance of the equivalent circuits of 3 types of broadband transducers and comparing them with the measured values. The equivalent circuit of a transducer is necessary for designing filters that match the impedances of the transducer and the power amplifier that drives the trans- ducer.