Sparse Arrays Method with Generalized Sidelobe Canceler Beamformer for Improved Contrast and Resolution in Ultrasound Ultrafast Imaging

The new ultrasound systems (US) based on the transmission of plane waves are able to generate videos with elevated frame rates when compared to the traditional techniques, allowing sophisticated exams. However, they generate a lot of data to be processed. Adaptive beam-former techniques are capable of reconstructing images with an elevate resolution, but with complex implementation and high processing demand. In this work it is suggested the use of a plane wave-based adaptive technique called Generalized Sidelobe Canceler (GSC). To evaluate the efficiency of this method with the decrease in the number of active elements of the transducer on reception, and consequent decrease in the amount of data generated, Sparse Arrays are considered. The evaluation of the proposed methods and comparison with the traditional method Delay and Sum (DAS) was performed using a simulated data set as well as in vivo collected data. The performance evaluation metrics were done using the Full Width at Half Maximum (FWHM) to check the lateral/axial resolutions, the contrast ratio (CR) and the and the Geometric Distortion Ratio (GDR). The results showed that the images generated by the proposed method, with a reduced number of active elements during the reception, were close to those provided by DAS in terms of spatial resolution and GDR, with the 65-element GSC method presenting GDR better than the DAS with 128 elements, indicating that the GSC method combined with proposed sparse arrays technique is suitable for imaging in B mode.