A Study On Models And Algorithms Based On EIT System And Optimization Of Low Pass Filter

With advantages over other CT techniques, e.g. non-intrusion, portability, lowcost and fast response, Electrical Impedance Tomography(EIT) has been investigatedextensively in the last decade, and found many important applications in both industrialand medical areas.In this paper, the current-injected EIT at low frequency has been studied in thefollowing aspects.Firstly, the image reconstruction process in EIT has been generalized to a closed-loop control schematic, so EIT problem is a control problem in nature, and somecomments on algorithms are given. Secondly, with the original idea to describe theshape of the electric field lines, a simple and intuitive model for uniform distributionhas been established, with some applications of the model presented. Thirdly, a preci-sion analytical model with a circular object has been introduced, as well as an analysisof convergence and discussions on its applications. Fourthly, a statistical investigationof the coupling effects of the popular used sensitivity matrix, which is calculated basedon the idea of perturbation, and the results show the limitations of methods based onsensitivity matrix and also the reason to keep some error in iterative process to com-pensate this coupling. Finally, an optimization of low pass filter based on non-idealoperational amplifier in EIT and associated methods to deal with similar coupling havebeen presented and some ideas on obstacles in EIT are provided.