Adaptive Ultrasound Imaging Using Forward-Backward Minimum Variance Beamforming and Coherence Weighting

The delay-and-sum (DAS) beam former is widely used in medical ultrasound imaging. However, DAS leads to images with limited resolution and contrast due to its data-independent nature. In this paper, the forward-backward minimum variance beam former (FBMV) and coherence factor (CF) weighting is combined and adapted to medical ultrasound imaging. Compared to minimum variance (MV) beam former, FBMV applies more accurate estimation of the array covariance matrix, resulting higher image resolution and contrast. In addition, CF weighting can reduce the side lobe levels by emphasizing the in-phase signals and reducing the out-of-phase ones. We have applied the proposed beam forming approach to simulated RF data, and the results show that an increased resolution and constrast are obtained compared to the regularized MV beam former.