Adaptive compensation of phase and magnitude aberrations

Abstract

A new method for aberration correction is presented. Using multiple receive beams reconstructed at each transmit direction, image artifacts due to imperfect beam forming can be identified and greatly reduced. Previous studies have demonstrated the efficacy of such a compensation algorithm for blocked elements. In this study, the algorithm is extended for magnitude and phase aberrations. Experimental results show that substantial improvements are possible for small amplitude and phase errors. The compensation method is less effective for large errors, however. Based on this, a two-step procedure is proposed for general aberration correction. First, cross-correlation processing is used to reduce significant phase errors. Then, the adaptive compensation method is applied to remove remaining artifacts due to blocked elements, amplitude aberrations, and residual phase errors. This two-step procedure is shown to be effective in significantly reducing image artifacts due to amplitude and phase errors.