SAMPLED APERTURE TECHNIQUES APPLIED TO B-MODE ECHOENCEPHALOGRAPHY.

Abstract

An electronically steered and focused multielement transducer array is used in an attempt to minimize acoustic aberrations caused by skull thickness variations. Aberrations like this have thus far limited practical utilization of B-mode scanners in clinical examinations of head structure. The sampled aperature approach permits utilization of numerous signal processing techniques which might improve target resolution and picture quality when imaging through an aberrating medium. Two approaches are discussed: a phase compensation technique based on an a priori knowledge of the phase character of the aberrating medium; and a sgnal processing scheme which is effective for one class of phase aberrations likely to be encountered. Fundamental consideration and differences of each approach are considered.