Adaptive compensation of phase and magnitude aberrations

摘要

A new method for aberration correction is presented. Usingnmultiple receive beams reconstructed at each transmit direction, imagenartifacts due to imperfect beam forming can be identified and greatlynreduced. Previous studies have demonstrated the efficacy of such ancompensation algorithm for blocked elements. In this study, thenalgorithm is extended for magnitude and phase aberrations. Experimentalnresults show that substantial improvements are possible for smallnamplitude and phase errors. The compensation method is less effectivenfor large errors, however. Based on this, a two-step procedure isnproposed for general aberration correction. First, cross-correlationnprocessing is used to reduce significant phase errors. Then, thenadaptive compensation method is applied to remove remaining artifactsndue to blocked elements, amplitude aberrations, and residual phasenerrors. This two-step procedure is shown to be effective innsignificantly reducing image artifacts due to amplitude and phase errors