title: Phase-aberration correction using signals from point reflectors and diffuse scatterers: basic principles.
abstract: Methods for correction of phase aberrations induced by near-field variations in the index of refraction are explored. Using signals obtained from a sampled aperture (i.e. transducer array), phase aberrations can be accurately measured with a correlation approach similar to methods used in adaptive optics and radar. However, the method presented here has no need for a beacon or an ideal point reflector to act as a source for estimating phase errors. It uses signals from random collections of scatterers to determine phase aberrations accurately. Because there is no longer a need for a beacon signal, the method is directly applicable not only to medical ultrasound imaging but also to any coherent imaging system with a sampled aperture, such as radar and sonar.
authors.affiliation: General Electric Med. Syst., Milwaukee, WI.
authors.forename: S W
authors.initials: SW
authors.lastname: Flax
authors.forename: M
authors.initials: M
authors.lastname: O'Donnell