Adaptive time-reversal mirror

The time-reversal mirror uses the received signal from a probe source to refocus the signal at the probe source location by backpropagating the time-reversed version of the received signal. In this study, an adaptive method is described to steer a null to an arbitrary position in a waveguide while maintaining a distortionless response at the probe source location. As an application, selective focusing in free space is demonstrated. (C) 2001 Acoustical Society of America.