Simulation Of Forward Propagated Signals In Acoustic Time Reversal

Time reversal (TR) is a technique based on the reciprocity principle of the wave equation that can be used to focus waves. In an enclosed system, comprising homogenous medium that includes no reflecting targets, it normally is impossible to use time reversal to focus ultrasound into the medium. Our proposed solution to this problem is to use simulations to produce signals that are subsequently time reversed and used for focusing. We show that one can model the forward propagation with finite-element method (FEM), then time-reverse it, and finally transmit it back to generate a time reversed focus in an experimental setup. The results show that accurate TR focusing can be achieved using simulated signals both in homogenous media and in media including distinct inclusions.