Modified synthetic focusing with direction of arrival function for ultrasound imaging

The main objective of this work is to assess the possibility of improving the achievable image quality using synthetic aperture (SA) approach and to evaluate the performance of the modified algorithm. The modified algorithm is based on the coherent summation of back-scattered RF echo signals with weights calculated for each point and for all possible combinations of transmit-receive pairs. Weights are calculated using the deformation of the direction of arrival (DOA). In this way, the algorithm takes into account the finite aperture of each individual element in transducer array. The performance of the approach is tested using Field II simulated SA data of point reflectors, which allows the visualization depth and lateral resolution to be estimated. Compared with conventional SF, results manifest that this work exhibits an increase in the penetration depth and a minor degradation in lateral resolution.