Phased array ultrasonic beam forming using oversampled A/D converters

摘要

A beam former in a PASS (phased array sector scanning) ultrasonic imaging system includes a set of sigma-delta modulators (201) which operate to separately digitize the received echo signal from each transducer element. The oversampled one-bit digital representations of each echo signal are delayed as required for beam steering and focusing, and are summed together. A decimator filter (213) reduces the sample rate of the digitized receive beam prior to display of the image resulting from the receive beam.