A COMPARATIVE-EVALUATION OF SEVERAL ALGORITHMS FOR PHASE ABERRATION CORRECTION

A common framework is presented to classify several phase correction t echniques. A subset of these techniques are evaluated through simulati ons which utilize 2-D phase aberration profiles measured in the breast . The techniques are compared based on their ability to reduce phase e rrors, stability, and sensitivity to noise and missing elements in the transducer array. Significant differences are observed in these measu res of performance when the size and location of the aperture area use d to generate a phase reference signal are varied. Techniques that uti lize a small correction reference region are more susceptible to noise and missing elements than techniques which use larger reference regio ns. The algorithms encounter problems in 2-D phase correction when mak ing the transition from one row to the next, due to the low intereleme nt correlation at the transition points. It is shown that the magnitud e of the interelement correlation is the key parameter governing phase correction performance.