Gholampour Amir, Cano Camilo, de Hoop Hein, van Sambeek Marc R H M, Lopata Richard G P, Wu Min, Schwab Hans-Martin
Photoacoustics and Ultrasound Laboratory Eindhoven (PULS/e), Department of Biomedical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
J Acoust Soc Am. 2025 Feb 1;157(2):1228-1240. doi: 10.1121/10.0035790.
Multi-aperture ultrasound and photoacoustic imaging systems improve the imaging quality in terms of contrast, field of view, and potentially resolution in comparison to single aperture setups. However, the behavior of signal-to-noise ratio (SNR) in these systems has not been well understood. In this study, we propose a low-parameter predictive model for signal analysis based on the Fourier diffraction theorem. Furthermore, an analytical approach for SNR estimation is devised for both coherent and incoherent compounding methods. The theory is evaluated in simulations and experiments. The results show a great agreement with the theoretical expectation of k-space model for both mono-static and bi-static signals. In addition, the evaluated noise power and peak SNR results follow the analytical expectations. As the number of compounded reconstructed datasets increases, the noise power increases linearly and non-linearly for coherent and incoherent methods, respectively. Still, as demonstrated in both theory and results, for correlated sources, the SNR increases linearly with the number of coherently compounded reconstructions, while it can remain unchanged or even reduced if incoherent compounding is employed. Moreover, for uncorrelated sources, it is shown that compounding different views from several spatially diverse apertures may lead to a decrease in SNR.
与单孔径设置相比，多孔径超声和光声成像系统在对比度、视野以及潜在分辨率方面提高了成像质量。然而，这些系统中信噪比（SNR）的行为尚未得到很好的理解。在本研究中，我们基于傅里叶衍射定理提出了一种用于信号分析的低参数预测模型。此外，针对相干和非相干复合方法设计了一种SNR估计的解析方法。该理论在模拟和实验中得到了评估。结果表明，对于单静态和双静态信号，其与k空间模型的理论预期高度吻合。此外，评估得到的噪声功率和峰值SNR结果符合解析预期。随着复合重建数据集数量的增加，相干和非相干方法的噪声功率分别呈线性和非线性增加。不过，正如理论和结果所示，对于相关源，SNR随相干复合重建次数线性增加，而如果采用非相干复合，SNR可能保持不变甚至降低。此外，对于不相关源，结果表明从几个空间上不同的孔径复合不同视图可能会导致SNR降低。
