A 3-D synthetic transmit aperture ultrasound imaging system with a fully addressed array usually leads to high hardware complexity and cost since each element in the array is individually controlled. To reduce the hardware complexity, we had presented the large-pitch synthetic transmit aperture (LPSTA) ultrasound imaging for 2-D imaging using a 1-D phased array to reduce the number of measurement channels $M$ (the product of number of transmissions, ${I}_{\text {T}}$ , and the number of receiving channels in each transmission, ${I}_{\text {R}}$ ). In this article, we extend this method to a 2-D matrix array for 3-D imaging. We present both numerical simulations and experimental measurements. We combined ${L}\,\,\times \,\,{L}$ adjacent elements into transmission subapertures (SAP) and ${K}\,\,\times \,\,{K}$ adjacent elements into receive SAPs in synthetic transmit aperture (STA) imaging. In the image reconstruction, we conducted the first attempt to apply and integrate Gaussian-approximated spatial response function (G-SRF) with delay and sum (DAS) to improve the image contrast, especially for the near-field targets. The imaging performance obtained from G-SRF was also evaluated numerically and compared with the previously presented frequency-domain SRF (Freq-domain SRF). The 3-D large-pitch synthetic transmit aperture (3-D-LPSTA) with G-SRF can provide a computationally efficient solution compared with the standard 3-D-STA method. With approximately 1900-fold reduction in the number of measurement channels, 3-D-LPSTA can provide image contrast comparable with the standard 3-D-STA with a full array and significantly better than using a periodically sparse array with similar complexity. In addition to reducing the system complexity, the 3-D-LPSTA achieves 700-fold reduction in computational complexity and 523-fold reduction in data storage. Finally, we evaluated and implemented the G-SRF using phantom data, which were consistent with the simulation results showing that the G-SRF can improve the image contrast. The results demonstrate that the proposed 3-D-LPSTA shows the great potential for designing an inexpensive ultrasound system to ensure the real-time 3-D clinical ultrasound imaging using large arrays. The limits of the proposed method were also discussed.

中文翻译：

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测量通道数量减少的3D大螺距合成传输孔径成像：可行性研究

具有完全寻址阵列的3-D合成发射孔径超声成像系统通常会导致较高的硬件复杂性和成本，因为阵列中的每个元素都是独立控制的。为了降低硬件复杂性，我们提出了使用一维相控阵进行二维成像的大间距合成发射孔径（LPSTA）超声成像，以减少测量通道的数量 $ M $ （传输次数的乘积， $ {I} _ {\ text {T}} $ ，以及每次传输中的接收通道数， $ {I} _ {\ text {R}} $ ）。在本文中，我们将此方法扩展到用于3D成像的2D矩阵阵列。我们同时提供数值模拟和实验测量。我们结合 $ {L} \，\，\ times \，\，{L} $ 相邻元素进入传输子孔径（SAP）和 $ {K} \，\，\ times \，\，{K} $ 在合成发射孔径（STA）成像中将相邻元素合并到接收SAP中。在图像重建中，我们进行了首次尝试，将高斯近似空间响应函数（G-SRF）与延迟和和（DAS）集成在一起，以提高图像对比度，特别是对于近场目标。还对从G-SRF获得的成像性能进行了数值评估，并与先前介绍的频域SRF（频率域SRF）进行了比较。与标准3-D-STA方法相比，具有G-SRF的3-D大间距合成发射孔径（3-D-LPSTA）可以提供计算有效的解决方案。通过减少大约1900倍的测量通道数量，3-D-LPSTA可以提供与标准3-D-STA具有完整阵列相当的图像对比度，并且显着优于使用具有类似复杂性的周期性稀疏阵列。除了降低系统复杂度之外，3-D-LPSTA的计算复杂度降低了700倍，数据存储降低了523倍。最后，我们使用幻像数据评估并实现了G-SRF，这与模拟结果一致，表明G-SRF可以改善图像对比度。结果表明，提出的3-D-LPSTA在设计廉价的超声系统以确保使用大型阵列进行实时3-D临床超声成像方面显示出巨大的潜力。还讨论了所提出方法的局限性。3-D-LPSTA的计算复杂度降低了700倍，数据存储降低了523倍。最后，我们使用幻像数据评估并实现了G-SRF，这与模拟结果一致，表明G-SRF可以改善图像对比度。结果表明，提出的3-D-LPSTA在设计廉价的超声系统以确保使用大型阵列进行实时3-D临床超声成像方面显示出巨大的潜力。还讨论了所提出方法的局限性。3-D-LPSTA的计算复杂度降低了700倍，数据存储降低了523倍。最后，我们使用幻像数据评估并实现了G-SRF，这与模拟结果一致，表明G-SRF可以改善图像对比度。结果表明，提出的3-D-LPSTA在设计廉价的超声系统以确保使用大型阵列进行实时3-D临床超声成像方面显示出巨大的潜力。还讨论了所提出方法的局限性。结果表明，提出的3-D-LPSTA在设计廉价的超声系统以确保使用大型阵列进行实时3-D临床超声成像方面显示出巨大的潜力。还讨论了所提出方法的局限性。结果表明，提出的3-D-LPSTA在设计廉价的超声系统以确保使用大型阵列进行实时3-D临床超声成像方面显示出巨大的潜力。还讨论了所提出方法的局限性。