摘要
An open-ended coaxial line reflection method especially suitable for meas-uring the dielectric properties of biological tissue in vivo is described.This method offersthe advantage of not requiring any special preparation of the samples to be measured but aclose contact with the open end of a coaxial line.It is,therefore,very convenient to acquirea large number of measurement data in broad band rapidly.The method may also be usedto measure the properties of other substances.The measuring system consists of a networkanalyzer controlled by a microcomputer and calibrated by using ANA procedure to elimi-hate the influnce of error network introduced by the adapter,some connectors,etc.In or-der to reach higher accuracy,the iterative method is used to determine the parameters ofthe equivalent circuit.Measurements of permeativities of some living tissues have been per-formed in the frequency band of 0.5-2GHz.Compared with the results known in somepapers,the validity of this method has been confirmed.The difference in dielectric proper-ties between living and dead tissues,and the tissue permeativites(ε)versus frequency andduration of measurement after death have also been measured.
An open-ended coaxial line reflection method especially suitable for meas- uring the dielectric properties of biological tissue in vivo is described.This method offers the advantage of not requiring any special preparation of the samples to be measured but a close contact with the open end of a coaxial line.It is,therefore,very convenient to acquire a large number of measurement data in broad band rapidly.The method may also be used to measure the properties of other substances.The measuring system consists of a network analyzer controlled by a microcomputer and calibrated by using ANA procedure to elimi- hate the influnce of error network introduced by the adapter,some connectors,etc.In or- der to reach higher accuracy,the iterative method is used to determine the parameters of the equivalent circuit.Measurements of permeativities of some living tissues have been per- formed in the frequency band of 0.5-2GHz.Compared with the results known in some papers,the validity of this method has been confirmed.The difference in dielectric proper- ties between living and dead tissues,and the tissue permeativites(ε)versus frequency and duration of measurement after death have also been measured.
