均匀磁场激励磁感应成像滤波反投影算法

通过亥姆霍兹线圈在中心区域建立正弦均匀的激励磁场,磁场方向近似直线,有助于简化逆问题的复杂度.建立了8通道磁感应测量系统仿真模型,采用滤波反投影算法重构出电导率分布.在滤波反投影算法中,首先用线性插值补充检测数据,然后用Hamming滤波器对数据进行滤波,同时加入窗口滤波器减少了涡流磁场发散对周围线圈的影响.加入不同噪声比的噪声干扰,测试了算法对噪声的抑制能力,实验结果表明该模型下运用反投影滤波算法可以重构出电导率的分布.

The filtered back-projection algorithm of magnetic induction tomography with uniform magnetic excitation

Helmholtz coils produce uniform sinusoidal magnetic field in the center region, and the direction of magnetic field is approximate straight line, to help simplify the complexity of inverse problems. The simulation models of an 8-channel magnetic induction tomography measurement system are built, reconstructing conductivity distribution with filtered back projection algorithm. In the filtered back projection algorithm, the detected data is supplemented by the linear interpolation first, and then filtered by the Hamming filter, while adding a window filter to reduce the impact of around the coil from the divergence of the magnetic field. The different noise ratio of noise is added in the detected data to test noise suppression ability of the algorithm. The experiment results show that this filtered back projection algorithm can reconstruct the conductivity distribution under this model.