Response of the excitation condition to electromagnetic tomography

Abstract Electromagnetic tomography (EMT) has potential practical value in the fields of industrial and biomedical detection. The sensitivity, stability and accuracy of the sensor system are significant in the detection of EMT. In this paper, the EMT excitation condition is analyzed through the COMSOL Multiphysics finite element analysis software. The effects on a sensor array of 8 equally spaced inductive coils are discussed in terms of two effects: the direct effect on the received signals due to the change of the excitation condition and the effect of variations on the sensitivity, which is calculated through the received signals. The relationship between the exciting frequency and the received signal is discussed both in the simulation and the experiment; a multi-coil excitation strategy is proposed, and the comparisons are presented. The results clearly show that the higher exciting frequency led to the higher received signal. The selection of the excitation strategy should be considered based on the object field distribution, and it is necessary to increase the coil number for the multi-coil excitation strategy to obtain a better performance. This paper estimates the sensing field status according to the simulation results and provides a theoretical foundation for image reconstruction optimization.

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