Method of coherent flow imaging using synthetic transmit focusing and acoustic reciprocity

A method for acoustic imaging, the method comprising:

• providing an acoustic imaging system including an acoustic transducer array and a processor;
• emitting collimated acoustic radiation from the acoustic transducer array at a target at three or more distinct incidence angles;
• receiving scattered acoustic radiation from the target with the acoustic transducer array;
• determining acoustic images of the target from the scattered acoustic radiation corresponding to each of the three or more incidence angles;
• computing an angular coherence image with the processor by
• i) averaging the acoustic images vs. angle to estimate an angular coherence function at each spatial point of the acoustic images;
• ii) integrating the angular coherence function over a predetermined angular range to provide the angular coherence image;
• providing the angular coherence image as an output.