학술논문
Inductively coupled wideband transceiver for bioimpedance spectroscopy (IBIS)
Document Type
Conference
Source
Proceedings of the 20th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. Vol.20 Biomedical Engineering Towards the Year 2000 and Beyond (Cat. No.98CH36286) Engineering in medicine and biology 1998 Engineering in Medicine and Biology Society, 1998. Proceedings of the 20th Annual International Conference of the IEEE. 4:1791-1794 vol.4 1998
Subject
Language
ISSN
1094-687X
Abstract
Most measurement devices for bioimpedance spectroscopy are coupled to the measured object (tissue) via electrodes. At frequencies >500 kHz they suffer from artifacts due to stray capacitances between electrode leads as well as between ground and object. The non-invasive measurement of the brain conductivity is hardly possible with surface electrodes. These disadvantages can be obviated by inductive coupling. The aim of this work was the development of a wideband transceiver. In order to define its specifications a feasibility study has been carried out with a simulation model for two different coil systems above a homogeneous conducting plate. According to simulation results both systems render possible to resolve conductivity changes down to 10/sup -3/(/spl Omega/m)/sup -1/ at 50 kHz. The sensitivity increases with the square of the frequency. The receiver electronics must then resolve voltages >=1 /spl mu/V at an excitation current of 1 A. We have realized a transceiver which matches these specifications with a S/N-ratio of 22 dB at 1 /spl mu/V. The frequency range is 50 kHz-5 MHz.