Ultra-high-frequency radio frequency identification tag antenna applied for human body and water surfaces

摘要

A novel ultra-high-frequency (UHF) radio frequency identification (RFID) tag antenna has been proposed in this article, which can be mounted on the surfaces of the human body and water. The proposed antenna is realized by an elliptical structure, whose long and short axes are 72 and 30mm, respectively. The tag antenna consists of an elliptical loop radiation element, microstrip feed lines, arc matching networks, and tuning patches. We have analyzed the antenna radiation characteristics influenced by the structural parameters of the antenna and the thicknesses of the human body and water. The simulation and measurement results show that the proposed antenna can operate steadily on the surfaces of the human body and water with good conjugate impedance matching. The maximum measured reading range of the tag antenna on the surfaces of the human body and water can reach 5 and 7 m, respectively. The novelties exhibited in the proposed antenna include an elliptical structure, the stable performance on the surfaces of the human body and water, small size, and long reading range.