title: New equivalent-electrical circuit model and a practical measurement method for human body impedance.
abstract: Human body impedance analysis is an effective tool to extract electrical information from tissues in the human body. This paper presents a new measurement method of impedance using armpit electrode and a new equivalent circuit model for the human body. The lowest impedance was measured by using an LCR meter and six electrodes including armpit electrodes. The electrical equivalent circuit model for the cell consists of resistance R and capacitance C. The R represents electrical resistance of the liquid of the inside and outside of the cell, and the C represents high frequency conductance of the cell membrane. We propose an equivalent circuit model which consists of five parallel high frequency-passing CR circuits. The proposed equivalent circuit represents alpha distribution in the impedance measured at a lower frequency range due to ion current of the outside of the cell, and beta distribution at a high frequency range due to the cell membrane and the liquid inside cell. The calculated values by using the proposed equivalent circuit model were consistent with the measured values for the human body impedance.
authors.affiliation: Okinawa National College of Technology, 905 Henko, Nago, Okinawa 9052192, Japan.
authors.forename: Koyu
authors.initials: K
authors.lastname: Chinen
authors.affiliation: Okinawa National College of Technology, 905 Henko, Nago, Okinawa 9052192, Japan.
authors.forename: Ichiko
authors.initials: I
authors.lastname: Kinjo
authors.affiliation: Okinawa National College of Technology, 905 Henko, Nago, Okinawa 9052192, Japan.
authors.forename: Aki
authors.initials: A
authors.lastname: Zamami
authors.affiliation: Okinawa National College of Technology, 905 Henko, Nago, Okinawa 9052192, Japan.
authors.forename: Kotoyo
authors.initials: K
authors.lastname: Irei
authors.affiliation: Okinawa National College of Technology, 905 Henko, Nago, Okinawa 9052192, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Nagayama
mesh_terms: D000465:Algorithms; D032701:Biomimetics / Q000379:methods*; D003198:Computer Simulation; D025802:Electric Capacitance; D017097:Electric Impedance; D004581:Electronics; D006801:Humans; D008954:Models, Biological; D010992:Plethysmography, Impedance / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: BIA; armpit electrode; equivalent electrical circuit model; human body impedance