LOW-POWER PASSIVE TRANSPONDER

摘要

The invention concerns a radio-frequency transponder (12) for contact-free identification with a reader (10), comprising: an antenna (24), an analog circuit (25) including a capacitor (32) an AC-DC converter (34), a modulator (40) and a demodulator (38), a logic control circuit (26), a storage unit (27). Said transponder (12) is designed such that: the antenna (24) and the capacitor (32) form together a resonant circuit, the clock extractor (36) processes the first signal (Tx) to extract therefrom a clock signal addressed to said modulator (38) as long as the voltage of said signal (Tx) exceeds a first threshold value, the converter (34) transforms the first signal (Tx) into a rectified signal, to power the transponder (12). The performances of the transponder, and more particularly energy recuperation and data transmission rate, are improved by the fact that the analog circuit comprises two clock extractors, one of low level type (35), the other of the high level type (36).