Abstract：In order to achieve simultaneous detection and imaging of high and low conductivity materials, a wide-band excitation method for the planar electromagnetic tomography is designed. Based on the electromagnetic characteristics of the coil and experimental results, an optimization method for the design of the planar coil array is investigated. Through the finite element model, the sensitivity matrix is obtained using the perturbation method and an improvement is proposed for the uniformity of the sensitivity matrix in order to improve the quality of image reconstruction. The image reconstruction of objects with different conductivity is investigated through the simulation model and the results verify that the proposed planar electromagnetic tomography method can reconstruct high and low conductivity materials. A wide-band excitation system for the planar electromagnetic tomography is built and experimental investigations are conducted on various materials with different conductivity. The experimental results show that the average correlation coefficient is 0.77 and the average location error is 4.46mm.
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2024, Vol. 45 
