Dual-Chip RFID Tag for Enhanced Indoor Localization of IoT Assets

In this paper, a dual-chip RFID tag antenna with two dipoles of different electrical lengths based on UHF band is proposed. The dipoles are etched on the same substrate to create differential and torus shaped beam radiation patterns. It allows an enhanced power-based orientation sensing of the tagged objects. The antenna is simulated using CST MWS with an input impedance of 23+j224 Ω to match the NXP UCODE G2iL passive RFID chip’s impedance. To achieve design compactness, a large dipole with differential beam is miniaturized using a meander line method and a small dipole is also designed on the other side of same substrate. The isolation between the dipoles is 21 dB. The backscattered power from the RFID reader is also analyzed, to demonstrate that the Angle of Arrival data can be extracted based solely on the backscattered power received at a conventional reader.