Title :
Design of multi-layered polygonal helix antennas for RFID readers in UHF band
Author :
Choo, Jaeyul ; Choo, Hosung ; Park, Ikmo ; Oh, Yisok
Author_Institution :
Sch. of Electron. & Electr. Eng., Hong Ik Univ., Seoul, South Korea
Abstract :
A new type of printed helix antenna, called the multi-layered polygonal helix antenna, is proposed as an RFID reader antenna in the UHF band. The wire of the antenna has vertical bends on multi-layered polygons, and the antenna was optimized for various antenna characteristics, such as bandwidth, CP bandwidth, efficiency, antenna size, readable range to tag, and directivity, using the Pareto GA. Based on tests of the optimal designs, the two-layered structure shows superiority over the one-layered structure in terms of the limit of gain within all antenna sizes. To verify our investigation, we fabricated the optimal two-layered polygonal helix and printed it on a cardboard substrate. The fabricated antenna. with kr = 3.2. exhibited 27.63% impedance bandwidth, 16.8% CP bandwidth, and a readable range of nearly 9 m2.
Keywords :
Pareto optimisation; UHF antennas; directive antennas; electric impedance; electromagnetic wave polarisation; genetic algorithms; helical antennas; microstrip antennas; radiofrequency identification; CP bandwidth; Pareto GA; RFID readers; UHF band; antenna size; efficiency; impedance bandwidth; multilayered polygonal helix antennas; optimal two-layered polygonal helix; printed helix antenna; read-range; Bandwidth; Design optimization; Helical antennas; National electric code; Pareto optimization; Polarization; Radiofrequency identification; UHF antennas; Wire; Wounds;
Conference_Titel :
Antennas and Propagation Society International Symposium, 2005 IEEE
Print_ISBN :
0-7803-8883-6
DOI :
10.1109/APS.2005.1551996
