Yang Yunjie, Jia Jiabin
Agile Tomography Group, School of Engineering, The University of Edinburgh, Edinburgh EH9 3JL, United Kingdom.
Rev Sci Instrum. 2017 Aug;88(8):085110. doi: 10.1063/1.4999359.
This paper presents the design and evaluation of a configurable, fast multi-frequency Electrical Impedance Tomography (mfEIT) system for real-time 2D and 3D imaging, particularly for biomedical imaging. The system integrates 32 electrode interfaces and the current frequency ranges from 10 kHz to 1 MHz. The system incorporates the following novel features. First, a fully adjustable multi-frequency current source with current monitoring function is designed. Second, a flexible switching scheme is developed for arbitrary sensing configuration and a semi-parallel data acquisition architecture is implemented for high-frame-rate data acquisition. Furthermore, multi-frequency digital quadrature demodulation is accomplished in a high-capacity Field Programmable Gate Array. At last, a 3D imaging software, visual tomography, is developed for real-time 2D and 3D image reconstruction, data analysis, and visualization. The mfEIT system is systematically tested and evaluated from the aspects of signal to noise ratio (SNR), frame rate, and 2D and 3D multi-frequency phantom imaging. The highest SNR is 82.82 dB on a 16-electrode sensor. The frame rate is up to 546 fps at serial mode and 1014 fps at semi-parallel mode. The evaluation results indicate that the presented mfEIT system is a powerful tool for real-time 2D and 3D imaging.
本文介绍了一种可配置的快速多频电阻抗断层成像（mfEIT）系统的设计与评估，该系统用于实时二维和三维成像，特别是生物医学成像。该系统集成了32个电极接口，电流频率范围为10 kHz至1 MHz。该系统具有以下新颖特性。首先，设计了一种具有电流监测功能的完全可调多频电流源。其次，开发了一种灵活的切换方案用于任意传感配置，并实现了一种半并行数据采集架构用于高帧率数据采集。此外，在高容量现场可编程门阵列中完成多频数字正交解调。最后，开发了一种三维成像软件——可视化断层成像，用于实时二维和三维图像重建、数据分析和可视化。从信噪比（SNR）、帧率以及二维和三维多频体模成像等方面对mfEIT系统进行了系统测试和评估。在16电极传感器上最高信噪比为82.82 dB。在串行模式下帧率高达546帧/秒，在半并行模式下为1014帧/秒。评估结果表明，所提出的mfEIT系统是用于实时二维和三维成像的强大工具。
