A novel piezoelectric hydrophone based on next generation single crystal

Ultra Electronics Maritime Systems is a company that designs, manufactures and sells underwater detectionsystems for military defense applications. Core to one of their main products, a towed sonar array, arepiezoelectric hydrophones that can detect pressures and flows with very high precision. In order to greatlyincrease the marketability of their towed array system, the size of the towed arrays, or more specifically, thesize of the hydrophones must be decreased by a factor of two.Since, these piezoelectric hydrophones are currently based on conventional PZT piezoelectric materials, webelieve that there are large sensitivity gains to be made by moving to a next generation piezoelectricsingle-crystal material. Since there is a tradeoff between hydrophone size and sensitivity, a more sensitivepiezoelectric material should allow us to reduce the size of the hydrophone. Switching to a new single-crystalmaterial is not as simple as replacing the PZT because the crystal orientation must be radially uniform andcongruent with the hydrophone.This project is focused on developing a crystal-based hydrophone that is half the size of the Ultra's currenthydrophones, but with equivalent sensitivity. To achieve this, the proper crystal dimensions and orientationmust be realized and since no piezo-crystal supplier retails these, it is necessary for us to grow our ownsingle-crystal piezoelectric in house. During this research engagement, our piezoelectric transducer researchgroup at Dalhousie University will produce hydrophone substrates with the proper crystal orientation anddimensions, whereas Ultra Electronics will assemble and characterize the hydrophone performance.