A Novel Adaptively-Weighted Non-Linear Beamformer for Conventional Focused Beam Ultrasound Imaging Systems: Initial Results

Abstract

This work reports a new non-linear beamforming method, namely, Filtered Delay adaptively-weighted Multiply and Sum (F-DawMAS) beamforming is reported for Conventional Focusing Technique (CFT). The proposed F-DawMAS beamformer was compared against the routinely used Delay and Sum (DAS) and Filtered Delay Multiply and Sum (F-DMAS) beamforming methods. Notably, in the proposed method optimal adaptive weights are computed for each pixel to compensate for the effects due to spatial variations in beam pattern in CFT technique. The proposed F-DawMAS is compared with F-DMAS, and DAS in terms, Lateral Resolution (LR), Axial Resolution (AR), Contrast Ratio (CR) and contrast-to-noise ratio (CNR), estimated from experiments performed on tissue-mimicking phantom. Experimental results show that F-DawMAS resulted in improvements of AR by 58 % and 49 %, LR by 60 % and 53 %, CR by 73 % and 43 %, and CNR by 40 % and 28 % compared to DAS and F-DMAS, respectively. Thus, a conclusion can be drawn that the newly proposed F-DawMAS outperforms F-DMAS and DAS.