动态电阻抗成像时空相关性重建方法研究

Research on spatio-temporal relativity reconstruction method in dynamic electrical impedance tomography

电阻抗成像(electrical impedance tomography,EIT)常用于监测物场中介质分布的动态变化。对于动态EIT系统,传统成像算法以牺牲图像质量为代价,提高成像速度。利用测量数据序列的时间、空间特性,改善重建图像质量,建立了基于时间-空间相关性的动态EIT成像数学模型,将动态阻抗图像序列的低秩特性引入到目标函数中。采用增广拉格朗日乘子(augmented Lagrange multiplier,ALM)法对模型进行求解。仿真和实验结果证明新方法能够在改善重建图像质量的同时提高成像速度,从而表明新方法的有效性。

Imaging objects in electrical impedance tomography( EIT) measurement are often used in the dynamic change of medium distribution monitoring field. For the dynamic EIT system,the traditional reconstruction algorithm improves the imaging speed at the expense of image quality. In this paper,the spatial-temporal property of the measurement data is exploited to improve the reconstruction quality. The dynamic mathematical model of EIT is established based on spatio-temporal representation,and the low-rank property of the dynamic impedance image sequence is introduced to objective function. The augmented Lagrange multiplier( ALM) method is applied to solve the new objective function. Both the simulation and experimental results show that the new method can improve the reconstruction quality and speed,which illustrate the effectiveness of the new method.