电容层析成像图像重建是一个严重的病态逆问题,正则化技术被广泛使用获得稳定解。提出了一种基于灵敏度梯度,结合单位阵和Laplacian算子构建正则化矩阵的非均匀ECT正则化重建算法。新算法与目前的常规正则化算法不同在于利用敏感场灵敏度梯度函数构造目标函数中的正则化项,局部区域正则化约束水平随着灵敏度位置改变,在整个成像区获得光滑性,同时保留分布边缘细节的高频信息,减少重建图像边缘模糊。实验验证了提出的非均匀正则化算法重建图像性能有明显改善。
ECT image reconstruction is a heavy ill-posed inverse problem, regularization methods are widely used to acquire stable solutions. An anisotropic regularization method for electrical capacitance tomography is proposed in this paper, in which the regularization matrix is constructed based on sensitivity gradient and using the combination of an identity matrix and a Laplacian operator. The difference between the new algorithm and common regularization one is that the regularization term of the objective function is generated using the sensitivity gradient function of the sensing field;and the constraint level of the local region regularization changes with the sensitivity variation spatially to achieve the consistent smoothing effect in the overall imaging region, and retain the high-frequency components of the detailed images, so as to reduce the edge blurriness of the reconstructed images. The experiment was performed to verify the proposed method, and the result shows that the image reconstruction performance of the proposed anisotrop- ie regularization algorithm is improved significantly.