Shishvan Omid Rajabi, Abdelwahab Ahmed, Saulnier Gary J
Annu Int Conf IEEE Eng Med Biol Soc. 2020 Jul;2020:1452-1456. doi: 10.1109/EMBC44109.2020.9175416.
A novel method for measuring the shunt impedance of current sources in Electrical Impedance Tomography (EIT) systems is introduced. In an EIT system, electrical currents with theoretical sum of zero, are applied to the body and any mismatch between the currents results in current going through an extra grounded electrode. Since the N - 1 current patterns applied in an N-electrode EIT system are orthogonal to each other, by introducing an additional linearly- independent current pattern, a system of linear equations can be established from which the unknown shunt impedances can be calculated. The framework of the proposed scheme is introduced and its effectiveness is validated through both simulation and practical implementation. The experimental results show that by measuring the shunt impedances with the proposed method and using those values to adjust the current sources, the current passing through the grounded electrode is significantly reduced.
介绍了一种用于测量电阻抗断层成像（EIT）系统中电流源分流阻抗的新方法。在EIT系统中，理论总和为零的电流被施加到人体上，电流之间的任何不匹配都会导致电流通过一个额外的接地电极。由于在N电极EIT系统中应用的N - 1个电流模式相互正交，通过引入一个额外的线性独立电流模式，可以建立一个线性方程组，从中可以计算出未知的分流阻抗。介绍了所提方案的框架，并通过仿真和实际实现验证了其有效性。实验结果表明，通过用所提方法测量分流阻抗并使用这些值来调整电流源，通过接地电极的电流显著降低。
