Determination of the optimal carrier frequency in harsh environments by parameter estimation

Transponders in harsh medical or industrial environments are often embedded in or covered by metal. Eddy currents in conductive materials affect significantly the transmission of energy to a RFID or sensor transponder. With the help of a parameter estimation the carrier frequency can be adapted to optimally supply the transponder with energy. This adaption leads, in cases where state-of-the-art systems do not find the optimum, to a significant improvement of the energy supply. Finally, efficient approaches are given to implement this technique in a real-time application for mobile readers.