A High Density 16-bit Polarization-Independent Chipless Passive RFID Tag


  • Adeel Nasir Khan Department of Electrical Engineering University of Engineering and Technology, Taxila, 47050, Pakistan
  • Shabbir Majeed Chaudhry Department of Electrical Engineering University of Engineering and Technology, Taxila, 47050, Pakistan
  • Rashid Saleem Department of Telecommunication Engineering University of Engineering and Technology, Taxila, 47050, Pakistan
  • Muhammad Farhan Shafique Center for Advanced Studies in Telecommunication (CAST) COMSATS University Islamabad, Park Road, Tarlai Kalan, Islamabad, 45550, Pakistan
  • Sabih ur Rehman School of Computing and Mathematics Charles Sturt University, Australia


Chipless RFID, Convoluted Square Loops (CSL), Internet of Things (IoT), multi-bit, passive tag, polarization independence


A compact, polarization-independent, chipless, passive Radio Frequency Identification (RFID) tag with 16 bits binary encoding is presented in this paper. The design is prepared with the placement of 16 Convoluted Square Loops (CSLs), in a nested loop arrangement. The proposed CSL structure is formed by inwards semicircular bending of each edge of a square geometry. This configuration not only offers high Quality (Q) factor for each resonance but also polarization independence. The design is fabricated on a 1.6 mm thick FR-4 substrate having an area of 20.8 mm × 10.8 mm. The presented design occupies small area with the bit density of 7.12 bits/cm2 and requires no unit cell repetition for enhancing the Q factor. The tag is tested on the frequency range of 2 to 26 GHz with various E-field polarizations, in order to achieve a polarization independent behavior.


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