A circularly polarized antenna for UHF RFID reader

This paper presents the design of a circularly polarized (CP) antenna for Radio Frequency Identification (RFID) reader using the ring slot microstrip antenna for Ultra High Frequency (UHF) band. The proposed antenna, which consists of a ring slot microstrip antenna with truncated U-slot, is placed on a FR4 substrate (εr = 4.5). The prototype antenna was… (More)