An Improved Perturbation Technique for Electrical Impedance Imaging with Some Criticisms

An improved perturbation technique for electrical impedance tomography is proposed. This improvement is based on simultaneous corrections. Previously the perturbation technique limited corrections to a central region of the image model. When the whole model was allowed to vary, the perturbation technique diverged unless simultaneous corrections were used. The size of the perturbation matrix was minimized by using only unique measurements. Some problems associated with the perturbation matrix are discussed. Namely, it is a highly nonlinear function of the resistivity perturbation amount, and it does not hold for profiles other than the one for which it was calculated.