Novel Monopole Antenna Design for UHF Circularly Polarized RFID Tag Antenna

The paper presents the design of a compact dual-band RFID tag monopole antenna. The proposed design composed of two coupled armed meander-lines having 90 degrees between them and mounted on 1.6 mm thick FR4 substrate backed by a partial ground plane. The antenna resonates at 850 MHz and 1.5 GHz and radiates circularly polarized waves. The simulation results using HFSS software showed promising performance with a bandwidth of 15 MHz at center frequency 850 MHz and 140 MHz at center frequency of 1.5 GHz, respectively. The higher resonance frequency showed better results regarding a bandwidth of 140 MHz and perfectly omnidirectional radiation pattern. The radiation efficiency of the proposed design is 75%.