In the present study, the synthetic signals from the combo tube are simulated by using
commercial electromagnetic numerical analysis software which has been developed based on a
volume integral method. A comparison of the simulated signals to the experiments is made for the
verification of accuracy, and then evaluation of five deliberated single circumferential indication
signals is performed to explore a possibility of using a numerical simulation as a practical calibration
tool. The good agreement between the evaluation results for two cases (calibration done by
experiments and calibration made by simulation) demonstrates such a high possibility.