A Miniaturized Printed Dipole with Non-Uniform Meander Lines for Ultra High Frequency – Radio Frequency Identification Passive Tags

A non-uniformly meandered printed dipole antenna is proposed to be used as a passive Ultra High Frequency – Radio Frequency Identification (UHF RFID) chip-based sensor tag. A printed, modified dipole antenna, with an overall size of 130 × 25 × 1.6 mm3 was used as a reference antenna, and its size was reduced by 32% by folding dipole arms and employing a non-uniformly meandered structure. A double T-match structure was introduced to match the conjugate impedance of the RFID chip, i.e. Rocky100. Simulations were carried out in ANSYS High-Frequency Structure Simulator (HFSS), etching the antenna on FR4 substrate. The meandered antenna, with an overall dimension of 88 × 25 × 1.6 mm3, exhibits better performance than the reference antenna. The bandwidth of the antenna covers the whole UHF spectrum from 860 – 960 MHz while exhibiting an omnidirectional radiation pattern. The theoretical read range of the tag according to the Friis transmission equation is 10.6 m at EIRP of 4 W. The proposed tag can be used to develop chip-based passive UHF RFID sensor tags by integrating sensors to the Rocky100 chip.