Depth and range shifting of a focal spot using a time-reversal mirror in an acoustic waveguide

Conti, Ste´phane; Roux, Philippe; Fink, Mathias
May 2002
Applied Physics Letters;5/13/2002, Vol. 80 Issue 19, p3647
Academic Journal
We present a technique based on time reversal to focus an acoustic field at any depth and range in a waveguide. We take advantage of the signal received from an acoustic beacon in the guide to build a time-reversed modified version of the field that refocuses at a different point in the waveguide. This method is based on the application of the images theorem in the guide and, as in the classical time-reversal experiment, it does not require a priori knowledge of the waveguide characteristics. Ultrasonic laboratory experiments and underwater acoustic simulations are presented and compared to classical time-reversal focusing results. © 2002 American Institute of Physics.


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