Title :
Two novel negative impedance converters for a UHF RFID antenna
Author :
Salem, N. Pelin M H ; Niver, Edip
Author_Institution :
King Abdullah Univ. of Sci. & Technol., Thuwal, Saudi Arabia
Abstract :
Novel designs of two different negative impedance converter (NIC) circuits, one is employing bipolar junction transistors (BJTs) and the other is employing junction field effect transistors (JFETs), operating in ultra-high frequency (UHF) band are investigated. The circuits are designed for passive radio-frequency identification (RFID) tag antennas to achieve better matching characteristics. A microstrip dipole antenna with an integrated negative impedance converter designed to cancel out the input capacitance of the antenna at the resonance frequency is designed, simulated, fabricated and measured. Obtained simulation results are compared to those of the same antenna without the NIC circuit and the improvement in operation bandwidth and input reflection coefficient is observed.
Keywords :
UHF antennas; bipolar transistors; dipole antennas; impedance convertors; junction gate field effect transistors; microstrip antennas; radiofrequency identification; BJT; JFET; NIC circuits; UHF RFID antenna; UHF band; antenna capacitance; bipolar junction transistors; integrated negative impedance converter; junction field effect transistors; microstrip dipole antenna; negative impedance converter circuits; passive radiofrequency identification tag antennas; reflection coefficient; resonance frequency; ultrahigh frequency band; Dipole antennas; Impedance; JFETs; Junctions; Radiofrequency identification;
Conference_Titel :
Antennas and Propagation Society International Symposium (APSURSI), 2012 IEEE
Conference_Location :
Chicago, IL
Print_ISBN :
978-1-4673-0461-0
DOI :
10.1109/APS.2012.6348826
