ELECTRONIC IDENTIFICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a transponder for an electronic identification system where a recovery voltage is increased and an operation range is increased. SOLUTION: An input of a transponder 20 is directly connected to an antenna 22 that is matched to a high input impedance, thus exposing a high input impedance (>400Ω). The transponder 20 increases a voltage on a capacitor C2 that is restored from a queue signal, thus enlarging the operation range of a system. A modulator 30 of the transponder is configured so that the rear scattering modulation of the queue signal is performed with a modulation depth of less 80% or preferably approximately 30%, thus enlarging the operation range of the system.