Měření impedanční spektroskopie pomocí frekvenční analýzy

Abstract

This thesis is focused on creating a method (an algorithm) for data processing from bioelectrical impedance measurements. The aim of this thesis is to determine frequency dependence of impedance using the created algorithm. Based on the magnitude ratio phase difference detection method, two different signals are measured from designed simple RC circuits, which simulate electrical properties of tissue. Those signals correspond to an RC and a reference resistor response to the excitation step input voltage. A part of the algorithm is a system identification process using approximation of transfer function parameters by the least squares method. The frequency dependence of bioelectrical impedance can be found from the approximated transfer function. This algorithm is created to be subsequently implemented on a microcontroller and then to be used directly for a bioelectrical impedance measurement device.