Focusing in transmit-receive mode through inhomogeneous media: The matched filter approach

It has previously been shown that in contrast to time delay focusing techniques that can only correct distortions produced by a thin aberrator located close to the transducer array, transmit-receive mode (TRM) focusing is able to compensate for distortion independently of the aberrator position. However, TRM focusing has only been described in the transmit mode. The extension of this matched filter focusing technique in the receive mode is presented. It is shown that it can be achieved using adaptive convolution techniques instead of delay line techniques. Theoretical and experimental results are presented