AN ECHO PULSE METHOD FOR MEASUREMENTS IN HIGH-PERFORMANCE HYPERSONIC TRANSDUCERS

The paper discusses a microwave echo technique for measuring the acous tic attenuation and the conversion factor of an high-performance trans ducer with allowance for energy dissipation. The technique is substant iated for the general case when the excitation system coupling a gener ator to a piezoelectric element is a lossless two-port (four-terminal) structure. Equations are set up, relating the acoustic attenuation in the sound guide, the conversion factor, and the efficiency of the tra nsducer system to the total loss, the echo pulse power ratio, the volt age standing wave ratio, and the phase of the reflection factor. Sever al practical recommendations are set forth for the implementation of t he technique and a numerical comparison is presented between the resul ts obtained by the conventional and proposed techniques.