A Miniaturized Split-Ring Resonator Antenna Solution Using a New Helical-Shaped Technique for Passive UHF RFID Tags

This paper introduces a compact antenna solution for passive UHF RFID tags based on a split-ring resonator (SRR) design. A novel helical approach is incorporated to minimize the tag's size. The traditional SRR's outer ring is expanded using modified strips forming four spirals, leading to a more compact antenna structure. The antenna is printed on a Rogers CuClad 250 substrate. It associated with the Alien Higgs 4 RFID IC, to ensure coverage of the U.S. UHF RFID band. With dimensions of 13.8 mm × 13.8 mm, the antenna achieves a read range of 3.68 meters and exhibits an input impedance of 20+j181. The advantages of the proposed antenna design include a low profile that allows easy integration into small objects. In addition, the antenna can be manufactured at low cost, making it suitable for mass production. Overall, the compact SRR antenna with the new helical technique is a promising solution for passive UHF RFID tags, offering efficient performance and practical advantages in various applications.