A transponder IC for wireless auto identification system

摘要

A batteryless, self-powered transponder used in the wireless auto identification system is proposed in this paper. The system works in a frequency of 915MHz. The transponder will extract energy from the RF field from the KFID station, and will store it for the following working phases. The transponder works in three phases. First, the transponder will decode the data bit from the RFID station. Most of the digital part do not work during this phase. Second, the transponder will process the data receive in the pre-phase and will execute proper operation to some corresponding register or memory unit. And at last, the transponder will send a data bit back to the RFID station by optionally reflecting some wave, which can be achieved by modulating the load of the transponder. The system can be divided into three blocks: analog part, digital part and memory part.