Zhu Q, Lionheart W R, Lidgey F J, McLeod C N, Paulson K S, Pidcock M K
Electrical Impedance Tomography Research Group, Oxford Brookes University, UK.
IEEE Trans Biomed Eng. 1993 Feb;40(2):163-8. doi: 10.1109/10.212056.
This paper describes the development of an adaptive electric current tomography system which contains a novel front-end analog architecture. Programmable voltage sources have been used to deliver currents into the study object and to avoid the difficulties of obtaining high quality current sources. Through inverting an admittance matrix, the system is capable of achieving a desired current drive pattern by applying a computed voltage pattern. The tomograph, operating at 9.6 kHz, comprises 32 driving electrodes and 32 voltage measurement electrodes. The study of system noise performance shows high SNR in the data acquisition which is enhanced by a digital demodulation scheme. In vitro reconstruction images have been obtained with the data collected by the tomograph.
本文描述了一种自适应电流断层成像系统的开发，该系统包含一种新颖的前端模拟架构。可编程电压源已被用于向研究对象输送电流，并避免了获得高质量电流源的困难。通过对导纳矩阵求逆，该系统能够通过施加计算出的电压模式来实现所需的电流驱动模式。该断层成像仪工作在9.6 kHz，包括32个驱动电极和32个电压测量电极。系统噪声性能研究表明，在数据采集中具有高信噪比，这通过数字解调方案得到了增强。利用断层成像仪采集的数据获得了体外重建图像。
