Carrier frequency adaptation approach

Readers for passive RFID and sensor transponders in harsh environments, e.g. for transponders embedded in or covered by metal in medical or industrial environments, need a particular design. It is a challenge to supply the transponder with energy, since a varying environment has a heavy impact on the transmission channels for energy and data. In our following suggestion for an optimal adaptive design, the influence of the environment is taken into account in a model of a transponder system. Applying our adaptation approach induces an improvement of 7:30 dB for the voltage at the transponder.