Printed RFID reader antenna with circular polarization for handheld operation

A novel circularly polarized antenna for ultrahigh frequency (UHF) radiofrequency identification (RFID) readers is proposed in this article. A prototype that operates in the UHF RFID band is successfully developed using an orthogonally truncated radiation patch, an obliquely slotted ground plane, and a 50-Ω microstrip line that proximally fed the antenna. All elements are printed on a microwave substrate in a vertical structure. The antenna dimension of 65 × 900 × 8 mm3 is suitable to use for handheld devices. The impedance bandwidth for 2.5 VSWR and the 3-dB axial-ratio bandwidth is 15.2% (880 MHz∼1025 MHz) and 6.5% (890 MHz∼950 MHz), respectively. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2792–2797, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27180