Performance analysis of electromagnetic ID transmission system using 3-D finite element method

Great notice is taken of electromagnetic ID (IDentity) transmission systems. Therefore, 3-D numerical analysis is useful for optimum design of high frequency ID card systems which have complex structure. In this paper, the authors propose a new method for computing the transmission performance by employing the 3-D finite element method. In this method, the current vector analysis and the magnetic field analysis are coupled. The effectiveness of this method is clarified through the comparison with the measured results of the induced voltage of the secondary coil. In addition, the influence of the angle formed by the primary and the secondary coils on the directivity is investigated.