Two algorithms for correcting phase aberration in a computer-controlled ultrasonic imaging system

Spatial inhomogeneities in the acoustic velocity of tissues degrade the performance of medical ultrasonic imaging systems. Two algorithms which can correct the phase aberration induced by the inhomogeneities are presented. The first algorithm adjusts the phases of signals transmitted and received from individual channels in a phased array scanner, one group of adjacent elements at a time. The second algorithm is based on the assumption that a phases error profile can be approximated by a sum of sine waves and the phase aberration can be corrected by subtracting components of the sum. Comparisons of the two algorithms are presented