Flexible Anti-Metal RFID Tag Antenna Based on High-Conductivity Graphene Assembly Film

Abstract

We propose a flexible anti-metal radio frequency identification (RFID) tag antenna based on a high-conductivity graphene assembly film (HCGAF). The HCGAF has a conductivity of 1.82 × 106 S m−1, a sheet resistance of 25 mΩ and a thickness of 22 μm. The HCGAF is endowed with high conductivity comparable to metal materials and superb flexibility, which is suitable for making antennas for microwave frequencies. Through proper structural design, parameter optimization, semiautomatic manufacturing and experimental measurements, an HCGAF antenna could realize a realized gain of –7.3 dBi and a radiation efficiency of 80%, and the tag could achieve a 6.4 m read range at 915 MHz on a 20 × 20 cm2 flat copper plate. In the meantime, by utilizing flexible polyethylene (PE) foam, good conformality was obtained. The read ranges of the tags attached to curved copper plates with different bending radii were measured, as well as those of those attached to several daily objects. All the results demonstrate the excellent performance of the design, which is highly favorable for practical RFID anti-metal applications.

Systematic design and prototyping of a low‐cost passive UHF‐RFID transponder

“…In terms of its performance as against current designs, our prototype transponder achieved a similar read range to that recorded by Reference 25. Although 38 delivered a longer read range, it cannot operate effectively on metal surfaces due to significant interference. More so, the longest read range recorded by Reference 39 proved most effective when compared with this work nonetheless, it has no flexibility.…”

“…The 70 × 17 × 0.3 mm 3 dimension of the tag antenna incorporated a folded dipole architecture and utilized meandering and end‐loading techniques to match the UHF‐RFID chip through a T‐match feeding network. As opposed to similar folded dipole designs which achieved at most 80% matching efficiency as seen in References 27,38, it is imperative to note that this degree of efficiency was realized with large tag antenna dimensions of (81 × 20 × n/a mm 3 ) and (84 × 15 × 1 mm 3 ) respectively when compared to this work. Thus, approximately 16% × 15% × 70% miniaturization attained in this regard increases the scope of transponders application.…”

Wearable Near-Field Communication Sensors for Healthcare: Materials, Fabrication and Application

“…In practical applications, it is very promising if multiple sensing modalities can be integrated into a single sensing platform [ 90 , 91 ]. It is worth noting that not all sensing elements can be integrated with NFC.…”

A Flexible and Low-Cost UHF RFID Tag Antenna for Blood Bag Traceability

“…Except for three tags [19,22,23], most are flexible. In addition, many flexible tag antennas have been developed for purposes different from the one addressed in this paper [28][29][30][31][32][33][34][35]. Among them, those based on paper material [28,29], highconductivity graphene assembly film (HCGAF) [30], inductive coupling loop [31], textile fabric and yarn [32,33], and PTFE and Kapton substrates [34,35] stand out.…”

“…In addition, many flexible tag antennas have been developed for purposes different from the one addressed in this paper [28][29][30][31][32][33][34][35]. Among them, those based on paper material [28,29], highconductivity graphene assembly film (HCGAF) [30], inductive coupling loop [31], textile fabric and yarn [32,33], and PTFE and Kapton substrates [34,35] stand out. Except for the tag antennas printed on PTFE and Kapton substrates, which are low cost and have ideal physical, thermal, and electrical proprieties [36,37] for inexpensive practical blood bag monitoring, the other materials are not suitable for this application, since the paper and textile fabric and yarn are not resistant to mechanical and thermal stress.…”