Ultrasound (US) imaging systems typically employ a single beamforming scheme which is the delay and sum (DAS) beamforming due to its reduced complexity. However, DAS results in low-quality images due to limited resolution and noise rejection. The restrictions of DAS have been overcome by, delay multiply and sum (DMAS) beamforming, by providing better contrast and resolution than DAS, making it especially preferable in cases where finer image details are required in larger depth of scans for an accurate diagnosis. But, DMAS is confined to transducer frequencies where the generated harmonics also fall in the processable frequency range of the US system. However, if US systems could provide the flexibility to reconfigure beamforming considering the restrictions of each beamforming scheme, it is possible to select the best beamforming according to the clinical requirement and system constraints. This work is a fundamental step towards enabling reconfigurable beamforming for on-the-fly selection among the DAS and DMAS beamforming schemes, with low reconfiguration overhead, specifically for each imaging scenario to aid better diagnosis. This could be of particular importance to whole-body ultrasound imaging where many organs are consecutively examined using a single transducer. Two novel architectures are proposed, that reconfigures between DAS and DMAS beamforming as a function of transducer's center frequency with minimum additional computational overhead. The implementation results of the proposed architectures on xc7z010clg400-1 FPGA are reported. The possibilities of pixel-level beamforming reconfigurability where the different tissue regions could be beamformed with either DAS or DMAS are also shown through simulations.

中文翻译：

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迈向用于超声成像的像素级可重构数字波束成形核心。

超声（US）成像系统通常采用单个波束成形方案，由于其降低的复杂度，因此是延迟和和（DAS）波束成形。但是，由于分辨率和噪声抑制能力有限，DAS会导致图像质量下降。通过提供比DAS更好的对比度和分辨率，延迟乘法和和（DMAS）波束成形技术克服了DAS的局限性，在需要更大扫描深度的更精细图像细节以进行准确诊断的情况下，它尤其可取。但是，DMAS仅限于换能器频率，其中产生的谐波也落在美国系统的可处理频率范围内。但是，如果考虑到每种波束成形方案的限制，美国的系统可以提供重新配置波束成形的灵活性，可以根据临床需求和系统限制选择最佳的波束成形。这项工作是朝着实现DAS和DMAS波束成形方案中的即时选择启用可重新配置波束成形的基本步骤，并且具有低重新配置开销，特别是针对每种成像场景以帮助更好地诊断。这对于使用单个换能器连续检查许多器官的全身超声成像尤其重要。提出了两种新颖的体系结构，它们可以在DAS和DMAS波束成形之间进行重新配置，并以换能器的中心频率为函数，并且具有最小的额外计算开销。报告了在xc7z010clg400-1 FPGA上提出的架构的实现结果。