Chipless RFID Tags Fabricated by Screen Printing using SWCNT Ink

Slot-type 3-bit chipless radio frequency identification (RFID) tags were fabricated by screen printing using single-walled carbon nanotube (SWCNT) ink and their radar cross section (RCS) responses were measured. The measured RCS responses were consistent with the simulated ones, and RCS magnitudes of 8.1 to 9.5 dB were obtained, which are sufficient for identifying the binary codes. Although the conductivity of SWCNTs is lower than that of thin metal films, we demonstrated that SWCNT-based chipless RFID tags could operate and identify information by the binary code encoded by using filled or not filled slots in the elements.