Title :
A Reconfigurable Passive UHF Reader Loop Antenna for Near-Field and Far-Field RFID Applications
Author :
Borja, Alejandro L. ; Belenguer, Angel ; Cascon, Joaquin ; Kelly, James R.
Author_Institution :
Dept. de Ingeniera Eletr., Electron., Autom. y Comun., Univ. de Castilla-LaMancha, Cuenca, Spain
fDate :
7/4/1905 12:00:00 AM
Abstract :
This letter presents a passive UHF printed loop antenna with left-handed loading. The RFID reader antenna can work at near- and far-field operation within the European UHF (865-868 MHz) band. The operation frequency and radiation properties can be modified by employing varactor diodes. Also, the antenna can work in the near-field region having a flat magnetic distribution in the interrogation zone. A comparative study with other passive RFID reader conventional antennas shows that the left-handed loop achieves stronger near H-field with good impedance matching. Design details, simulated results, and a fabricated prototype are presented. The concept significantly extends the design degrees of freedom for RFID antennas.
Keywords :
UHF antennas; antenna radiation patterns; impedance matching; loop antennas; metamaterial antennas; microstrip antennas; radiofrequency identification; varactors; European UHF band; degree of freedom; far-field RFID application; flat magnetic distribution; frequency 865 MHz to 868 MHz; impedance matching; interrogation zone; left-handed loop antenna; near-field RFID application; operation frequency; radiation property; reconfigurable passive UHF reader printed loop antenna; varactor diode; Capacitors; Loaded antennas; Loading; Radiofrequency identification; UHF antennas; Left-handed loading; loop antenna; metamaterials; radio frequency identification (RFID);
Journal_Title :
Antennas and Wireless Propagation Letters, IEEE
DOI :
10.1109/LAWP.2012.2200870
