Rectenna design for passive RFID transponders

This work emphasises rectenna design issues of passive RFID transponders for 868/915-MHz and 2.45-GHz ISM bands. The characterisation of transponder chip takes into account the impact of connecting antenna to rectifier by flip-chip bonding process. Proposed experimental way allows finding chip impedance exactly as it seen by antenna. Refined rectifier circuitry effectively overcomes dependence of transponder performances on the type deviation of connected antennas.