Maxwell-Wagner relaxation in electrical imaging.
The electric field tomography (EFT) method exploits interaction of high-frequency electric field with an inhomogeneous conductive medium without contact with the electrodes. The interaction is accompanied by a high-frequency redistribution of free charges inside the medium and leads to small and regular phase shifts of the field in the area surrounding an object. Such a kind of phenomenon is referred to as the Maxwell-Wagner relaxation. Measuring the perturbations of the field using the set of electrodes placed around the object enables us to reconstruct the internal structure of the medium, generally the spatial distribution of a nonlinear combination of permittivity and resistivity. In the case of biomedical applications the result of measurements is determined mainly by the resistivity of the tissues. Three-dimensional simulation based on the finite element method has demonstrated the feasibility of the technique.
Korjenevsky
A V
AV
Institute of Radio-engineering and Electronics of the Russian Academy of Sciences, Mokhovaya 11-7, Moscow, 125009, Russia. korjenevsky@cplire.ru
D000465:Algorithms; D000818:Animals; D001823:Body Composition / Q000502:physiology*; D003198:Computer Simulation; D017097:Electric Impedance; D004566:Electrodes; D004574:Electromagnetic Fields; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008954:Models, Biological; D010992:Plethysmography, Impedance / Q000379:methods*; D014054:Tomography / Q000379:methods*