Characterization of a 13.56 MHz RF-ID system based on scattering parameters approach

The efficient setup and deployment of modern radio frequency identification (RF-ID) systems operating at 13.56 MHz require an accurate knowledge of the reading range associated to the reader unit. To evaluate the reading range, an efficient simulative approach is analyzed in this paper, based on the evaluation of scattering parameters and a computer aided design (CAD) modeling. In particular, a two-port numerical model is considered and the parameter S_2,1 analyzed. The purpose is to propose an efficient and original approach, based on S-parameters, in order to characterize an RF-ID system at 13.56 MHz in terms of reading range. Some key working conditions of RF-ID systems are also analyzed in terms of inductive coupling between reader and tag coils.