Research On Dynamic EIT Imaging Method Based On Spatiotemporal Characteristics

Electrical Impedance Tomography(EIT)has been investigated extensively during the past decades as a noninvasive visualization and measurement technique.The EIT technique has the advantages of portable,safety,low cost,non-invasive and rapid measurement.EIT has wide application prospect in the fields of medical imaging,industrial imaging and geological exploration.In this fields,it is often necessary to monitor the dynamic process of the change of the medium distribution in the object field by the EIT technique,that is,the conductivity distribution of the region of interest varies with the change of time.However,The traditional dynamic EIT imaging algorithm is based on the measured information of each frame.Improving the imaging speed while ensuring the imaging quality is still facing many challenges.Dynamic EIT image reconstruction algorithm based on the spatio-temporal correlation was proposed to solve above problems.According to temporal correlation of adjacent frames measurement data field changes,the low rank EIT imaging system framework is proposed,the objective function of the dynamic EIT based on low-rank method is established,and the ALM algorithm is used to solve the function.Furthermore,low-rank method combined with sparity method for EIT imaging is proposed to improve the image quality,the characteristic of spatial redundancy properties of the dynamic EIT image is used.The validity of the method is verified by simulation and system experiment.Compared with traditional methods,the algorithms proposed in this paper can improve the reconstructed speed and the quality of the image.Furthermore,the new methods enhance the robustness of the image to the noise.Among them,the low-rank method has the fastest imaging speed,and it is more suitable for dynamic imaging applications that require higher imaging speed.The combination of low-rank and sparse methods has the best imaging quality and faster imaging speed,and it is more suitable for the biomedical imaging at the same time which need to take into account-the imaging accuracy and speed of the occasion.