Electrical Impedance Spectroscopy Using a Wide-Band Signal Based on the Rudin-Shapiro Polynomials

Abstract

Electrochemical Impedance Spectroscopy (EIS) has become an increasingly important diagnostic and monitoring tool in many industries. An obstacle that arises when employing EIS in low and ultra low sub-Hz frequencies is the long measurement time associated with using the conventional frequency-sweep method. One possible solution to this problem is to use wide-band signals that cover at once the entire frequency range of interest. In this work, we explore and validate the use of such a signal obtained from the Rudin-Shapiro polynomial over the frequency range 10 mHz to 10 Hz. The proposed signal was first applied on an RC circuit and the results were compared to the classical frequency-sweep method for verification. The technique was subsequently applied to measure strawberry bio-impedance for age monitoring applications.