基于压缩感知的ECT/CT双模融合系统成像方法  

Image reconstruction method based on compressive sensing for ECT/CT dual modality fusion system

作　　者：王琦[1] 张荣华[2] 王金海[1] 王化祥[3] 

机构地区：[1]天津工业大学电子与信息工程学院,天津300387 [2]天津工业大学电气工程与自动化学院,天津300387 [3]天津大学电气与自动化工程学院,天津300072

出　　处：《仪器仪表学报》2014年第6期1338-1346,共9页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(60820106002;61072101;61201350;61001135;61301246);天津市自然科学基金(11JCYBJC06900)资助项目

摘　　要：过程成像(PT)技术以两相/多相流为主要测量对象。ECT/CT双模融合可拓宽过程层析成像技术的测量范围,实现信息的互补与融合。设计了ECT/CT双模态传感器,提出测量数据融合方法及其成像数学模型。针对融合后数据采集量增大,影响系统响应速度的问题,基于压缩感知原理,对测量数据随机采样,并运用L1正则化算法重建图像,在不影响成像质量的前提下,进一步提高成像速度,以适应在线观测与控制多相流型的需要。Process tomography （PT） is widely used in two-phase/multi-phase flow measurement. Because the characteristics of electrical capacitance tomography （ECT） and computerized tomography （CT） are complementary and the sensitivity fields of the two techniques are non-interfering, the dual-modality fusion of these two techniques can expand the measurement scope of the PT and achieve information complementation and fusion. The ECT and CT systems are fused, and a dual-modality tomography system is designed in this paper. The measurement data fusion method and the imaging mathematic model are proposed. The fusion sensor combines the advantages of both ECT and CT, hence the measurement scope of PT is expanded and the quality of the reconstructed images is improved. In order to improve the response speed of the fusion system, the random sampling method based on the principle of compressed sensing is adopted. L1 regularized method is used to solve the inverse problem, which is a non-linear method and suitable for reconstructing images from random sampling data. Both simulation and experiment were carried out, the results indicate that the proposed method can reduce the computational time and improve the quality of reconstructed image with suitable decomposition levels. This method can also be applied to on-line multiple-phase flow regime observation.

关 键 词：双模融合 压缩感知 稀疏表达 图像重建 

分 类 号：TH701[机械工程—仪器科学与技术]