High precision impedance measurement based on gigabit transceiver

Abstract

In this study, impedance measurement is implemented using the vector current-voltage method. The zero-crossing method is used to separate the real and the imaginary parts of the impedance vector, and the phase difference information is acquired using the high-speed data acquisition method. However, the limitation of the resolution of the phase difference often prevents the improvement of the accuracy of the impedance measurement. Therefore, in this paper, we propose a method for high-resolution phase measurement based on high-speed acquisition technology. Using the gigabit transceiver integrated in the XILINX K-7 Series field-programmable gate arrays, we achieve a sampling rate of 6 Gbps or higher, thereby improving the resolution of the phase difference time and considerably improving the accuracy of the impedance measurement.