Numerical estimation of Fricke-Morse impedance model parameters using single-frequency sinusoidal excitation

Physiol Meas. 2019 Sep 30;40(9):09NT01. doi: 10.1088/1361-6579/ab3666.

Abstract

Objective: The Fricke-Morse impedance model is widely used in bioelectrical impedance analysis (BIA), which is usually fitted by multi-frequency electrical impedance data. Here, we propose a novel numerical method for estimating the model parameters using single-frequency sinusoidal excitation.

Approach: A single-frequency sinusoidal signal is used as the current excitation, from which the initial transient, the steady-state and the ending transient voltage responses along with the current excitation are recorded. The model parameters can be then estimated with numerical calculations from the acquired signals.

Main results: Simulation and experimental measurements are verified on a 2R1C circuit by using a 50 kHz sinusoidal current excitation. The results show that the maximum relative errors of the estimated model parameters are <1% in simulation with 2% noise and <2% in experimental measurement.

Significance: The proposed method could extend the applications of wideband BIA by using single-frequency excitation, rather than multi-frequency excitation as is done today.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Electric Impedance
  • Models, Statistical*
  • Signal Processing, Computer-Assisted