Frequency difference fast Newton's one-step error reconstructor (FNOSER) imaging method for electrical impedance tomography

Abstract

The invention relates to a high-accuracy signal measurement-based frequency difference fast Newton's one-step error reconstructor (FNOSER) imaging method for electrical impedance tomography, which comprises an electrical impedance tomography and an imaging method for high-accuracy signal measurement. The electrical impedance tomography comprises a shell, an electrode array, an excitation module, a measuring module, a central control processing circuit, a universal serial bus (USB) communication module and an upper computer. The imaging method is characterized by comprising the following steps of: (1) acquiring a boundary voltage by using an electrical impedance tomography measuring system when an excitation current frequency is fr, wherein the boundary voltage is taken as a reference voltage Vp; (2) acquiring a boundary voltage by using the electrical impedance tomography measuring system when the excitation current frequency is fm, wherein the boundary voltage is taken as a measuring voltage Vu; (3) computing the Jacobi matrix J of a tested model; (4) substituting a measured value and a computed value into an FNOSER algorithm to compute resistivity distribution; and (5) drawing a resistivity distribution map. The system error of the measuring system can be constrained in the aspect of algorithm, a method which is practical and feasible for determining initial resistivity is disclosed, the resistivity distribution of the tested model can be reconstructed rapidly and correctly and electrical impedance dynamic imaging effect is improved remarkably.

Description

technical field [0001] Aiming at the bottleneck problem that the system error cannot be eliminated and the initial resistivity is not easy to choose during the reconstruction process of the inverse problem in the electrical impedance imaging system (Electrical Impedance Tomography, EIT), the present invention invented an imaging algorithm based on frequency difference FNOSER. Background technique [0002] Electrical Impedance Tomography (EIT) is a distinctive imaging technology that is mainly used in clinical medical diagnosis. EIT technology applies electrical excitation to the human body through an electrode array arranged on the human body surface and measures its electrical response signal, from which the electrical characteristic information of tissues and organs related to human physiological and pathological states can be extracted, which can not only reflect the anatomical structure, but also Gives a functional image result. EIT technology does not use nuclides or r...

AI Technical Summary

Problems solved by technology

FNOSER frequency difference reconstruction can obtain a clear and stable impedance distribution image, and has a good tolerance for errors, which solves the bottleneck problem that the system error cannot be eliminated and the initial resistivity is not well selected.

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