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阻抗ＣＴ技术是通过在物体的边界进行一些电测量来重建内部阻抗分布。本文提出利用网络理论来解决阻抗ＣＴ的一种新的重建方法。首先将非均匀电导分布区域离散化为具有一些节点的电导网络，然后在边界节点上施加一组正交的电流激励，测量感生出的电压。根据网络论，这样就可利用网络的节点方程来进行求解．为求得最符合观测值的节点电导矩阵Ｇ的估计，我们从Ｇ的性质中提取了两类约束，根据广义投影理论，采用施加约束的迭代方法来重建这一反映电导分布的节点电导矩阵Ｇ．计算机模拟表明，迭代是收敛的并且能得到较好的重建结果。
Impedance CT technology rebuilds the internal impedance distribution by making some electrical measurements at the object’s boundaries. In this paper, we propose a new reconstruction method of impedance CT using network theory. First, the non-uniform conductance distribution area is discretized into a conductance network with some nodes, and then a set of orthogonal current stimuli is applied at the boundary nodes to measure the induced voltage. According to the network theory, this can be solved using the node equations of the network. In order to obtain the best estimate of node conductance matrix G, we extract two types of constraints from the properties of G. According to the generalized projection theory, we use the iterative method to impose the constraint to reconstruct the node conductance matrix G . Computer simulation shows that the iteration is convergent and can get better reconstruction results.