Design and Synthesis Methodology for UHF-RFID Tags Based on the T-Match Network

A new systematic methodology for the design of T-match based UHF-RFID tags is proposed. The great majority of commercial UHF-RFID tags are based on dipole antennas using a modification of a T-match network. The literature contains examples of models that describe the T-match, but they are not sufficiently accurate to synthesize the tag geometry. Using the proposed methodology, a global band UHF-RFID tag based on a folded dipole antenna and matched to the RFID integrated circuit by means of a T-match network is designed and fabricated. Very good agreement between the measured and simulated read range is achieved within the entire UHF-RFID band, which reveals that the proposed method is amenable for accurate analysis and synthesis of T-match based UHF-RFID tags.