A Dual Frequency Circularly Polarized UHF-RFID/WLAN Circular Patch Antenna for RFID Readers

This paper presents a simple circular patch antenna with slots on the patch and slits on the ground plane to achieve dual band operability and circular polarization at both respective frequencies. The operating frequency bands include the UHF-RFID band at 915 MHz and the WLAN band at 2.45 GHz. The antenna is planar, has a single port, is very easy to design and fabricate and also very cost efficient. RFID readers can be equipped with this antenna to communicate with tags via the 915 MHz (UHF-RFID) band and send the received information to data centers via the 2.45 GHz (WLAN) band.