Title :
Circularly polarized circular microstrip RFID tag antenna
Author :
Yen-Ming Tseng ; Shang-Huang Kuo ; Horng-Dean Chen ; Sim, Chow-Yen-Desmond
Author_Institution :
Dept. of Optoelectron. & Commun. Eng., Nat. Kaohsiung Normal Univ., Kaohsiung, Taiwan
Abstract :
A compact circularly polarized circular microstrip tag antenna designed for RFID UHF band is presented. A cross slot of unequal arm lengths embedded in a circular patch is used to achieve compact CP operation. By choosing the proper lengths of two short-circuited arc microstrip lines and its coupling distance, good complex impedance matching can be obtained. The measured 10-dB return-loss bandwidth of the tag antenna is 40 MHz (901-941 MHz), while its 3-dB axial-ratio bandwidth is 6 MHz (912-918 MHz). Further experiment shows that the tag antenna can provide better reading range when mounted on a metallic surface.
Keywords :
UHF antennas; impedance matching; microstrip antennas; microstrip lines; radiofrequency identification; slot antennas; RFID UHF band; bandwidth 40 MHz; bandwidth 6 MHz; circularly polarized circular microstrip tag antenna; compact CP operation; complex impedance matching; coupling distance; cross slot antenna; frequency 901 MHz to 941 MHz; loss 10 dB; metallic surface; short-circuited arc microstrip lines; unequal arm lengths; Antenna measurements; Frequency measurement; Impedance; Microstrip; Microstrip antennas; Radiofrequency identification; Circular polarization; microstrip antenna; radio frequency identification (RFID); tag antenna;
Conference_Titel :
Microwave Conference Proceedings (APMC), 2012 Asia-Pacific
Conference_Location :
Kaohsiung
Print_ISBN :
978-1-4577-1330-9
Electronic_ISBN :
978-1-4577-1331-6
DOI :
10.1109/APMC.2012.6421850
