Title :
Compact Integrated Antenna With Circulator for UHF RFID System
Author :
Lim, Won-Gyu ; Son, Wang-Ik ; Oh, Kyoung Sub ; Kim, Wan-Kyu ; Yu, Jong-Won
Author_Institution :
Dept. of Electr. Eng., Korea Adv. Inst. of Sci. & Technol. (KAIST), Daejeon
fDate :
6/30/1905 12:00:00 AM
Abstract :
A passive UHF radio frequency identification (RFID) reader antenna with high transmit/receive isolation, which consists of two quadrifilar spiral antennas (QSAs) and the feeding networks, is proposed. The high isolation can be achieved by two concentric, circularly polarized antennas and 4-point feed circuits, which make the same circular polarization. The simulated and experimental results show that the transmit/receive isolation is more than 40 dB and the gains of two QSAs are 1.0 dBi for the inner QSA and 0.7 dBi for the outer QSA at the 910 MHz, respectively.
Keywords :
UHF antennas; circulators; polarisation; radiofrequency identification; spiral antennas; UHF RFID system; circular polarization; circulator; compact integrated antenna; feeding networks; frequency 910 MHz; quadrifilar spiral antennas; Antenna isolation; RFID; circular polarization; circulator; quadrifilar spiral antenna; quadrifiliar spiral antenna; radio frequency identification (RFID);
Journal_Title :
Antennas and Wireless Propagation Letters, IEEE
DOI :
10.1109/LAWP.2008.921348