The Design Of Rfid Chipless TAG

Radio frequency identification (RFID) technology is a kind of wireless communications technology which exploits radio signal to achieve automatic target recognition. The technology allows not only storing a relatively large amount of information about the target, but also changing and processing information. In the21th century, with the rapid development of Internet of Things, everything will be connected to information through wireless communication. RFID technology, as a wireless automatic identification technology, becomes more and more important.This article is focus on the design of RFID chipless tag in RFID system. The design of tag is an important part in RFID system. This design in this article is based on multi-spiral filter stopband and frequency selective surface (FSS), respectively.The RFID chipless tag based on multi-spiral filter include two parts. The key part is the multi-spiral filter which placed on coplanar waveguide. The bandwidth is3.5-5.5GHz and code storage is10bit. A ultra wide band (UWB) antenna based on microstrip is designed to transmit and receive signal. The overall size of the antenna is23×36×0.8mm3.The resonant frequency is3.5GHz and bandwidth is3-12GHz. The multi-spiral filter is simulated and optimized by ADS, the result of S parameter is good. The microstrip monopole antenna is simulated by HFSS. The antenna is fabricated. The simulation and measurement result agrees well.Two chipless RFID tag are designed by metallic patch and aperture structure based on frequency selective surface theory. The first chipless RFID tag is comprised by FR-4substrate^FSS and ground. The overall size of the tag is30×30×0.8mmm3The bandwidth of the tag is3-10GHz and the code storage is5bit. The second chipless RFID tag is comprised by FR-4substrate and FSS. The overall size of the tag is25×25×0.8mm3.The bandwidth is3-10GHz and the code storage is5bit. For the aperture structure, we reduced its size to its1/4based on current analysis theory. In this way, the overall size of the tag reduced75%to12×10×0.8mm5The miniaturization of the chipless RPID tag is achieved. The aperture type tag is fabricated. The simulation and measurement result agrees well.