A Compact Chip-less RFID Tag for IoT Applications

This paper presents a compact and cost effective chip-less RFID tag (CRFID) to be operated in 4–14 GHz band. The tag has circular and diagonal closed loop rings for generating multiple resonances to encode a 12-bit sequence. It has a size of
$\mathbf{1.4}\times\mathbf{1.4\ cm}^{\mathbf{2}}$
and code density of 6.122 bits/cm
²
. The proposed tag is modeled upon low cost FR4 substrate and has a planar construct. Due to its attractive features such as long bit-encoding capability, compact size and ease of fabrication, this CRFID is deemed quite suitable to be used in various RFID application scenarios in Internet of Things.