Simulation of impedance measurements at human forearm within 1 kHz to 2 MHz

摘要

This work presents a simulation analysis of the bioimpedance measurements at human forearm. The Ansys? High Frequency Structure Simulator (HFSS) has been used to analyze the electrical response of a section of human forearm with three domains of di-electric behavior- fat, muscle and artery (blood). The impedance values were calculated as the ratio of the output voltage at the electrodes to the applied known current (1mA). A model was developed and was simulated for impedance values obtained within a frequency range of 1 kHz to 2MHz. The measurements were done at three instances of radial artery diameter. The maximum resistance and reactance values were calculated as 445Ω and 178.5Ω, 356Ω and 138Ω, and 368Ω and 144.3Ω for diameters 2.3mm, 2.35mm, and 2.4mm respectively. The set of impedance values obtained followed Cole-plot trend. The results obtained were found to be in excellent agreement with the Cole theory. The set of values obtained at three different diameters reflected the effect of blood flow on impedance values.