Optimization of the matching layer for high-frequency underwater acoustic transducers

A theoretical model has been established to investigate the dependence of matching layer functional mechanism of matching layer on excitation signal types, i.e., short pulse and long pulse. The results indicate that the matching layer acts as a bandpass frequency filter under both two excitation signal types. In the short pulse case, the matching layer can improve bandwidth and sensitivity simultaneously, whereas for the case of long pulse excitation, the increased bandwidth is at the expense of sensitivity. Besides, the thickness design principle of matching layer for underwater acoustic transducer was modified according to the frequency-dependent acoustic radiation impedance.