Real time impedance plots with arbitrary frequency components.

Abstract:

:Temporal changes in the impedance spectra of bioelectrodes in contact with skin provide useful data for comparisons between differing electrode materials and skin preparation methods. Traditional impedance measuring systems employ swept frequency methods which will distort results in the impedance spectra of a sample which has nonstationary electrical characteristics. The system reported here obtains impedance spectra by applying a digitally constructed waveform consisting of many frequency components. This allows impedance values to be measured at a number of frequencies simultaneously. Sample data are provided and compared with data obtained using similar square wave techniques.

journal_name

Physiol Meas

authors

Searle A,Kirkup L

doi

10.1088/0967-3334/20/1/008

subject

Has Abstract

pub_date

1999-02-01 00:00:00

pages

103-14

issue

1

eissn

0967-3334

issn

1361-6579

journal_volume

20

pub_type

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