Innovative Decentralized Configuration Design of Chipless RFID Tag: Toward a Cost-Effective and Efficient Code Density

In this article, a compact chipless RFID tag with a small size and high data density is proposed. The tag consists of nested octagonal loops arranged in a concentric configuration. Each two neighboring resonating elements are decentrally coupled by two connector lines at obverse sides. The small size of the tag is achieved through embedding multiple octagonal elements in a nested arrangement, which share the same side, and through connecting the neighboring elements. The tag configuration is designed and optimized to improve the resonating modes with respect to the number of resonating elements. The number of generated resonating modes (N) is mathematically obtained by N=2n-1, such (n) is the resonating elements number. An 11-bits data capacity is presented in the proposed tag within a physical dimension of
$10\times10$
mm2, resulting high data density of 11 b/cm2. The proposed tag is realized on Rogers RT/Duroid 5880 substrate having substrate height h=0.508 mm, relative permittivity
$\epsilon _{r}=$
2.2, and loss tangent
$\delta = 0.0009$
. The proposed tag is designed and simulated using CST Studio Suite ®. The tag’s performance is initially evaluated through simulation and analyzed for effectiveness. The tag is then fabricated and measured, and the results are compared to ensure agreement between simulation and measurement. The tag advantages are compact size, high data density, and improved resonating modes. The operating frequency range of the proposed tag is 7.5 GHz-15 GHz.