Design of a wideband and bi-directional transducer for underwater communications

Abstract

A two ceramic layer stacked transducer structure for short range underwater communications at high frequencies is studied in this work. The structure has a wide bandwidth of one octave and operates at 350 kHz center frequency. Transducer structure inherently has two electrical and two acoustic ports. Ceramic layers are matched to water load through quarter wavelength thick matching layers on each radiating face. Using electrical ports separately to compensate for the large acoustic length of the structure in water is also investigated. It is shown that the wide bandwidth operation can be maintained. The beamwidth of the structure is narrow due to end - fire effect of two back – to – back radiating elements.