A Slim Wideband and Conformal Uhf Rfid Tag Antenna Based on U-Shaped Slots for Metallic Objects

Abstract

Abstract-A slim wideband patch antenna designed for the ultrahigh frequency (UHF) band radio frequency identification (RFID) tag is presented in this paper, which can be mounted on flat or curved metallic surfaces directly. The presented antenna is fabricated on a very thin (only 0.5 mm) and low-cost PET substrate (ε r = 3.8, tan δ = 0.02). The proposed design consists of tow coplanar patches radiation unities which are electrically connected to the metallic ground through two symmetrical shorting walls placed at both edge sides of the patches. Double symmetrical U-shaped slots are etched out to improve the antenna bandwidth. A perfect matching between antenna and tag chip can be easily obtained by varying the geometry parameters of the slots. The simulated bandwidth is about 97 MHz, which covers the Europe and North America UHF RFID frequency range. The measured maximum reading range of the proposed antenna can be up to 5 m when the tag is mounted on a metal plate whose size is 150 × 150 × 8 mm 3 .

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

“…The Tagformance Lite was employed to measure the reading range of the tag. The results are shown in Figure .…”

Review of Metal-Resistant Structures for Radio Frequency Identification Tag Antennas

“…The EBG structure, known for its ability to truncate the propagation of electromagnetic waves, also contributes to metal resistance when applied in antennas [21]. Wang et al utilized a ground plane with EBG and a double-layer substrate structure to reduce coupling and reflection between the antenna and metal objects, achieving metal-resistant characteristics [22]. Some scholars employed a double-layer rectangular mushroomtype EBG structure to increase the total inductance of EBG, enhancing its resistance to metal, although the suppression of surface waves was not sufficiently strong [23].…”

Folded ring slot antenna reader for UHF RFID applications using artificial magnetic conductor structure

“…In a RFID system, the position of the tag plays an important role. Depending on the application, it can be put on different materials causing losses of playback such as metals or human tissues for bio‐monitoring . Therefore, a solution lies in the use of circular polarization antennas .…”