A coplanar waveguide-fed folded-slot monopole antenna for 5.8 GHz radio frequency identification application

Design of a simple coplanar waveguide (CPW)-fed patch antenna for radio frequency identification (RFID) application is presented. The radiation mechanism of such an antenna has been investigated, based on a moment-method numerical analysis and experimental measurement. The antenna with a symmetrical folded slot to become a U-shaped monopole can excite 5.8 GHz resonance mode with impedance bandwidth of 490 MHz, average antenna gain of ≥4.1 dBi, and monopole-like radiation patterns but has a compact antenna size. These properties make the antenna suitable for use in RFID tags. In addition, an equivalent circuit model for such kind of antenna is also presented to account for its radiation characteristics. Good agreement between the simulated and modelled results has been obtained. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 71–74, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22051