International Journal of Antennas and Propagation (Jan 2017)

CPW-Fed Wideband Circular Polarized Antenna for UHF RFID Applications

  • Sun-Woong Kim,
  • Guen-Sik Kim,
  • Dong-You Choi

DOI
https://doi.org/10.1155/2017/3987263
Journal volume & issue
Vol. 2017

Abstract

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We propose a wide bandwidth antenna with a circular polarization for universal Ultra High Frequency (UHF) radio-frequency identification (RFID) reader applications. To achieve a wide 3 dB axial ratio (AR) bandwidth, three T-shaped microstrip lines are inserted into the ground plane. The measured impedance bandwidth of the proposed antenna is 480 MHz and extends from 660 to 1080 MHz, and the 3 dB AR bandwidth is 350 MHz and extends from 800 to 1155 MHz. The radiation pattern is a bidirectional pattern with a maximum antenna gain of 3.67 dBi. The overall size of the proposed antenna is 114 × 114 × 0.8 mm3.