A broadband transducer with tube-beam coupling structure is presented. Flexural beams are put into a traditional segmented ring transducer including inactive portions to form a new tube-beam coupling structure with more useful working modes. Using multiple-mode- coupling design technique, the bandwidth of transducer could be expanded efficiently towards low frequency range. The optimization study of the electroacoustic parameters is carried out by finite element analysis at first. Then a prototype is manufactured and measured. It is shown that this projector combines the fine qualities of flextensional transducer with those of circular ring transducer by both the simulated and experimental results. It could achieve low frequency, high power and wide band performance from compact size. In addition, it is suitable for deep submergence operation when using free-flooded design.
