Abstract:
:Conventional bioimpedance spectrometers measure resistance and reactance over a range of frequencies and, by application of a mathematical model for an equivalent circuit (the Cole model), estimate resistance at zero and infinite frequencies. Fitting of the experimental data to the model is accomplished by iterative, nonlinear curve fitting. An alternative fitting method is described that uses only the magnitude of the measured impedances at four selected frequencies. The two methods showed excellent agreement when compared using data obtained both from measurements of equivalent circuits and of humans. These results suggest that operational equivalence to a technically complex, frequency-scanning, phase-sensitive BIS analyser could be achieved from a simple four-frequency, impedance-only analyser.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Ward LC,Essex T,Cornish BHdoi
10.1088/0967-3334/27/9/007subject
Has Abstractpub_date
2006-09-01 00:00:00pages
839-50issue
9eissn
0967-3334issn
1361-6579pii
S0967-3334(06)18497-Xjournal_volume
27pub_type
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