Simple Implementations of the Cole-Cole Models

Abstract

A novel procedure for the circuit implementation of the single and double dispersion Cole-Cole models is presented in this work. The concept is that the impedance of the whole model is approximated and implemented by appropriately configured RC networks, instead of the conventional implementation method where the approximation of each one of the fractional-order capacitors is required. The approximation is performed through the utilization of a curve fitting technique, where both magnitude and phase frequency responses of the total impedance are fitted by a rational integer-order driving point impedance. The main offered benefit is the reduction of the number of passive element count, especially in the case of the double dispersion Cole-Cole model. The behavior of the resulting structures, in terms of accuracy and robustness, is evaluated through simulation results.