Effects from imaging parameters of sub-aperture averaging in minimum variance adaptive beamforming using outputs of delay-and-sum beamformer

We proposed a reduction method of the computational cost for the minimum variance (MV) adaptive beamforming. In the method, a receiving aperture was divided into several sub-apertures, and outputs of the delay-and-sum (DAS) beamformer in the divided sub-apertures were used as inputs of the MV beamformer. Lateral resolutions were evaluated under different division numbers, distances between sub-apertures, and their overlapping ratios in sub-aperture averaging. As a result, the resolution was improved by 44.3% compared with the DAS method at a distance between sub-apertures of 1 mm (5 elements) when dividing the aperture by 5 in sub-aperture averaging.