Study on Sweeping Frequency of Electrical Impedance Tomography System

A 16-electrode sweeping frequency electrical impedance tomography (SFEIT) system based on the numeric electromagnetism field theory is presented in this paper. Excitation with flexible frequency and intensity is introduced to the SFEIT system, and this improvement can get much more impedance information of the object. The model of the interface impedance between electrode sensor and the object is presented, two experiments done indicate that the interface impedance and parasitic parameter that always causes errors sharply varies with frequency. So comparing with traditional EIT, SFEIT can flexibly choose the intensity and frequency of the excitation according to the characteristic of the object impedance so as to minimize the error and get more accurate information for image reconstruction.