Phase-Encoded Chipless RFID Transponder for Large-Scale Low-Cost Applications

Abstract

A novel 3 b chipless RFID transponder is presented. The transponder comprises three microstrip patch antennas, which are loaded with open circuited (O/C) high impedance stubs. The antennas are resonant at nearby frequencies, and when excited with their respective resonant frequency signals, they re-radiate backscattered signals with distinct phase characteristics. This phase information is encoded as hexadecimal bits for the proposed chipless RFID tag. Both the CST Microwave Studio full-wave solver and the anechoic chamber measurements show a 30deg phase step for the 3 b chipless RFID transponder. It it easily transferred to printed technology, and it may find applications in the mass identification market.