2-D sparse arrays may push the development of low-cost 3-D systems, not needing to control thousands of elements by expensive application-specific integrated circuits (ASICs). However, there is still some concern about their suitability in applications, such as Doppler investigation, which inherently involve poor signal-to-noise ratios (SNRs). In this article, a novel real-time 3-D pulsed-wave (PW) Doppler system, based on a 256-element 2-D spiral array, is presented. Coded transmission (TX) and matched filtering were implemented to improve the system SNR. Standard sonograms as well as multigate spectral Doppler (MSD) profiles, along lines that can be arbitrarily located in different planes, are presented. The performance of the system was assessed quantitatively on experimental data obtained from a straight tube flow phantom. An SNR increase of 11.4 dB was measured by transmitting linear chirps instead of standard sinusoidal bursts. For a qualitative assessment of the system performance in more realistic conditions, an anthropomorphic phantom of the carotid arteries was used. Finally, real-time B-mode and MSD images were obtained from healthy volunteers.

中文翻译：

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稀疏螺旋阵列的实时3-D频谱多普勒分析

2-D稀疏阵列可以推动低成本3-D系统的发展，而无需通过昂贵的专用集成电路（ASIC）控制数千个元件。但是，对于它们在应用中的适用性仍存在一些担忧，例如多普勒研究，这固有地涉及较差的信噪比（SNR）。在这篇文章中，提出了一种新颖的实时3D脉冲波（PW）多普勒系统，该系统基于256个元素的2D螺旋阵列。实施了编码传输（TX）和匹配滤波以提高系统SNR。沿着可以任意放置在不同平面中的线，显示了标准声谱图以及多门频谱多普勒（MSD）曲线。根据从直管流动体模获得的实验数据对系统的性能进行了定量评估。通过传输线性chi而不是标准正弦波突发，可以测量出SNR增加了11.4 dB。为了在更现实的条件下对系统性能进行定性评估，使用了拟人化的颈动脉模型。最后，从健康志愿者那里获得了实时B模式图像和MSD图像。