Current Source for Wideband Electrical Bioimpedance Spectroscopy Based on a Single Operational Amplifier
2006 (English)In: WORLD CONGRESS ON MEDICAL PHYSICS AND BIOMEDICAL ENGINEERING 2006, VOL 14, PTS 1-6 / [ed] Kim, SI; Suh, TS, 2006, 707-710 p.Conference paper (Refereed)
Traditionally, measurements of electrical bioimpedance for medical diagnostic purposes have used only low frequencies, usually below 100 kHz. The analysis focused only on the resistive part of the impedance; very often at low frequencies the reactive part of the impedance is negligible. Recent studies of the electrical bioimpedance spectrum, both real and imaginary parts, have indicated new potential applications e.g. detection of meningitis, skin cancer assessment and brain cellular edema detection. An important functional unit in a wideband impedance spectrometer is the current source used to inject the current into the tissue under study. A current source must provide an output current virtually constant over the frequency range of interest and independent of the load at the output. Several designs have been proposed over the years but the performance of them all degraded markedly near bellow 1 MHz e.g. Ackmann in 1993, Bragos et al in 1994 and Bertemes-Filho et al in 2000. The development of electronic technology has made available devices that allow us to obtain a current source with large output impedance, larger than 100 k Omega, above I MHz and based in a simple single Op-Amp circuit topology. Simulation results and experimental measurements are compared and the most important parameters of the VCCS are analytically studied and experimentally tested, including the dependency to changes in the circuit elements and the incidence of the Op-Amp parameters on the current source features.
Place, publisher, year, edition, pages
2006. 707-710 p.
, IFMBE Proceedings, ISSN 1680-0737 ; 14
Bioimpedance Spectroscopy, Current Source, Electrical Bioimpedance, Four-Electrode Technique
Medical Laboratory and Measurements Technologies Signal Processing
IdentifiersURN: urn:nbn:se:kth:diva-74894ISI: 000260855900154ScopusID: 2-s2.0-84958243116ISBN: 978-3-540-36839-7OAI: oai:DiVA.org:kth-74894DiVA: diva2:490159
World Congress on Medical Physics and Biomedical Engineering. Seoul, SOUTH KOREA. AUG 27-SEP 01, 2006
QC 201202062012-02-032012-02-032016-05-18Bibliographically approved