Title :
Instrumentation considerations for complex impedance measurements
Author :
Ackmann, James J.
Author_Institution :
Dept. of Neurosurg., Med. Coll. of Wisconsin, Milwaukee, WI, USA
Abstract :
The extension of complex impedance measurements and associated analytic techniques to the study of biologic systems is discussed. Because of the highly conductive nature of animal tissue, special care must be taken in instrumentation design to achieve useful data. A recently fabricated system for use in the frequency range from 5 Hz to 700 kHz is presented. At higher frequencies, the finite output capacitance of the current source (approximately 3 pf) and the finite input capacitance of the voltage sensing system (approximately 6 pf) cause unacceptable phase errors
Keywords :
bioelectric phenomena; biological techniques and instruments; electric impedance measurement; 5 Hz to 700 kHz; animal tissue; biologic systems; complex impedance measurements; current source; finite input capacitance; finite output capacitance; frequency range; instrumentation design; phase errors; voltage sensing system; Amplifiers; Biological materials; Capacitance; Composite materials; Conducting materials; Frequency; Impedance measurement; Instruments; Neurosurgery; Voltage;
Conference_Titel :
Engineering in Medicine and Biology Society, 1989. Images of the Twenty-First Century., Proceedings of the Annual International Conference of the IEEE Engineering in
Conference_Location :
Seattle, WA
DOI :
10.1109/IEMBS.1989.96170
