Optimum ON/OFF resistances of the ASK modulator for passive RFID tags

In this paper, we propose optimized ON/OFF resistances for the backscattering amplitude-shift keying (ASK) modulator for a passive RFID tag considering the effective backscattered power level. Based on an analysis of power transfer between the passive RFID tag and reader, we obtain the optimal condition for the ASK modulator to maximize the harvestable power. We calculate the performance of the proposed modulator configuration that is superior to the conventional scheme.