A 12 bits chipless RFID tag based on ‘I-shaped’ slot resonators

In this paper, a 12 bits chipless tag is designed on a 42mm*20.5mm*0.5mm Arlon AD255A substrate. The tag is based on 12 `I-shaped' slot resonators. By removing or adding some slots, different codes are obtained. HFSS software is used in structure design and simulation. In order to reduce the mutual coupling between different resonators and have the compact size, the distance between two adjacent `I-shaped' slots is designed to be 1mm, and the width of `I-shaped' slot is 0.5mm. Low profile Ultra-Wide Band (UWB) Co-planar Waveguide (CPW) antennas are used in experiment instead of using expensive horn antennas. From simulation and experimental results, the chipless tag proposed in this paper is feasible and it has great potential in the field of Internet of things.