Experimental Verification and Design Guidelines for Efficient Ultrasonic Power Transfer Using Capacitive Parametric Ultrasonic Transducers

Capacitive parametric ultrasound transducers (CPUT) passively harness energy from ultrasound signals without the need for a DC bias, making them especially useful in wireless power transfer applications. In earlier works, CPUTs were analyzed using a 1D lumped parameter model which did not consider the complex acoustic interactions in realistic transducers with many membranes. For practical device design and implementation, experimentally validated full-scale simulations should be used. In this work, a CPUT model using the boundary element method (BEM) to model membrane arrays is implemented and used to study effects of multi-mode behavior on power transfer. The results indicate that CPUTs with practical micromachined membrane geometries can provide efficiency levels suitable for remote power transfer.