Modified open stub multi-resonator based chipless RFID tag

Abstract

A planar, fully printable, frequency signature based multi-resonator circuit for chipless RFID transponder system and swipe card is presented. The amplitude and/or group delay of the spectral signature are utilized for the chipless tag or swipe card multi-resonator circuit, providing a 1: 1correspondence of data bits. It comprises of a bifurcated microstrip transmission line meeting at the far end within which the open circuited shunt stub multiresonators are positioned. The developed structure can be used effectively as a swipe card. The application of the proposed circuit together with its cross-polarized transmitting and receiving microstrip ultra-wideband disc loaded monopole antennas for RFID transponder system is also presented. The experimental and simulated results in support of the potentials of the chipless tag for low cost item tagging such as bank notes and secured documents are explained in this paper. The circuit is having high quality factor and has a very small footprint of 24x10mm 2 .

Orientation Independent Chipless RFID Tag Using Novel Trefoil Resonators

“…Frequency selective surface (FSS) repetitions are not essential for this design, resulting in a 1:1 resonator to bit correspondence. Such characteristics allow for the tag design to be fairly compact [37]. The proposed resonant design exhibits no 2 nd harmonic and a negligible 3 rd harmonic, eliminating the presence of spurious peaks within a wide range of frequencies [38].…”

A high capacity tunable retransmission type frequency coded chipless radio frequency identification system

“…A microstrip line section loaded with L‐shaped stubs was used to code eight data bits . A bifurcated microstrip line loaded with linear stubs achieved the same coding capacity in smaller dimension . This article presents a more compact data capturing circuit with better coding capacity, drawing from the concepts presented in ref.…”

“…This article presents a more compact data capturing circuit with better coding capacity, drawing from the concepts presented in ref. [], along with the inclusion of U‐shaped stubs and exclusion of tapered section. The proposed topology is depicted in Figure .…”

“…The table highlights that there is a clear trade‐off between the different listed performance parameters. For instance, though achieved very high bit capacity per unit normalized area, their designs did not cater for resonance detuning owing to closely spaced resonators. Besides the tag designs of refs.…”

“…The literature survey reveals five main categories of the planar multi‐resonators. These include modified transmission line resonators, transmission line coupled resonators, stepped impedance resonators, multi‐resonant high impedance surfaces, and semi‐lumped resonators . Furthermore, the tags utilizing retransmission approach for communication have better read range compared to the ones with backscattering approach owing to the presence of dedicated transmitting and receiving antennas.…”