Analysis of Energy Transmission for Inductive Coupled RFID Tags

The significance of passive RFID labels is growing in logistic processes. While the initial aim was to identify items with an invariable identification code, new applications with enhanced functionality arise which need additional energy. This contribution investigates the requirements on an inductive coupled RFID radio link in order to provide a reliable power transmission under varying coupling conditions to a battery less tag. In addition to the transponder, the investigations also imply the reader unit. The optimum coil turn configuration is derived and the quality factor of the resonant circuits is taken into account. A consecutive planning for an optimum system design is given. Simulation results are validated by measurements.