Efficient network modeling of inductively coupled NFC antennas in medical wireless sensor applications

In this paper, a parametric modeling technique for a fast polynomial extraction (FPE) of the physically relevant network parameters of inductively coupled radio frequency identification / near field communication (RFID/NFC) antennas is presented. The input parameters for the approach are extracted by means of the Partial Element Equivalent Circuit (PEEC) method and the “Reduced Broadband Self-Impedance Models”. The parameters can be approximated very efficiently over the entire geometrical input parameter range of an antenna class with the presented method. The modeling approach is extended to lumped element models suitable for time domain simulations, including skin- and proximity effects. In a parameter study, the obtained network models are compared to the results of a reference PEEC solver with regard to accuracy and computation effort. Furthermore, a good agreement between simulation and measurement results is shown for an antenna configuration.