TY - JOUR A2 - Chen, Z. N. AU - Lertsakwimarn, Kittima AU - Phongcharoenpanich, Chuwong AU - Fukusako, Takeshi PY - 2013 DA - 2013/11/26 TI - Circularly Polarized Low-Profile Antenna for Radiating Parallel to Ground Plane for RFID Reader Applications SP - 349817 VL - 2013 AB - This paper presents a low-profile printed antenna with double U-shaped arms radiating circular polarization for the UHF RFID readers. The proposed antenna consists of double U-shaped strip structures and a capacitive feeding line to generate circular polarization. A part of the U-shaped arms is bent by 90° to direct the main beam parallel to the ground plane. From the results, -10 dB |S11| and 3 dB axial ratio of the antenna cover a typical UHF RFID band from 920 MHz to 925 MHz. The bidirectional beam is obtained with the maximum gain of 1.8 dBic in the parallel direction to the ground plane at the 925 MHz. The overall size of the proposed antenna including ground plane is 107 mm × 57 mm × 12.8 mm (0.33λ0 × 0.17λ0 × 0.04λ0). SN - 1687-5869 UR - https://doi.org/10.1155/2013/349817 DO - 10.1155/2013/349817 JF - International Journal of Antennas and Propagation PB - Hindawi Publishing Corporation KW - ER -