Metal mountable UHF-RFID tag antenna with meander feed line and double T-match

Abstract

A compact ultra-high-frequency (UHF) RFID tag with meander feed line and double T-match structure is proposed. The tag is composed of a copper layer at the upper and bottom side of a Rogers 5880 substrate, with the relative permittivity of 2.2 and a UCODE G2XM/G2XL chip from NXP Semiconductor. The tag with the overall dimension of 58 × 34 × 0.85 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> is not sensitive to the objects it is attached to including metallic object since the performance of the tag in free air and on metal objects remains almost the same. The double T-matching technique is implemented in the antenna design to easily match the antenna and the chip impedance. The antenna is designed to operate in Malaysia frequency range (919 - 923 MHZ). The performance of the tag is evaluated through simulation in terms of impedance matching, reflection coefficient and reading range.