UHF RFID tag antenna based on the DLS‐EBG structure for metallic objects
Xiuping Li, Gege Gao, Hua Zhu, Quanping Li, Ning Zhang, Zhenguo Qi
Abstract
In this study, a novel compact radio frequency identification (RFID) tag antenna with a combination of a dipole and the double‐layer symmetric electromagnetic band gap (DLS‐EBG) structure is proposed for metallic objects in ultra‐high‐frequency (UHF) band. The DLS‐EBG unit cell consists of a symmetrical double‐layer structure and offset vias for tag miniaturisation. The equivalent circuit model of the unit cell is developed to analyse reflection phase characteristics. The measurement results show that the bandwidth ranges from 876 to 992 MHz and the impedance matching of the tag remains stable as the metal plate changes. The reading distance of the tag on the metal plate is up to 12.3 m under the transmitted equivalent isotropic radiated power (EIRP) of 36 dBm. Measurement and simulation results agree well.