Dual frequency mode transducer

In oceanic engineering, dual mode transducers are useful. With high frequency transducers it is easy to obtain a narrow beam and increased accuracy. Low frequency sound waves propagate under water with less attenuation and, therefore, have a greater operational range. So a sonar system with two operating frequencies will offer distinct advantages over a single frequency system. Employing laminated Tonpilz assemblies which operate both in the longitudinal and radial mode is a simple and effective way to obtain dual mode transducers. Design techniques and the analysis of the two modes are discussed