When RFID tags are brought closer to each other, the acquisition by the radio frequency reader of the data they contain becomes difficult because of the strong coupling related to the respective radiation of their antennas. This radiation is at the origin of the birth of mutual impedances adapting the antenna and its integrated chip. This article proposes an electrical modeling of this coupling for different configurations of RFID tags. The approach is based on two-port network theory and antenna arrays. The coupling capacity between tags is determined on the one hand by using a numerical simulation based on the finite elements and on the other hand from an analytical model with the parameters of the antenna. The analytical results are in good agreement with the numerical results. The working frequency is the 868 MHz ISM band.
Show abstract
Full Text
