Eccentric circular ring RFID tag antenna for dual-band operation

Abstract

In this letter, a dual-band ultra high frequency (UHF) passive RFID tag antenna covering the 865-868 MHz band and 950-956 MHz band is proposed. The antenna has two eccentric circular rings, each of which resonates at one of these two bands. Both the rings are simultaneously excited by an arc-shaped short-circuited microstrip line by the coupling-feed technique. The proposed structure exhibits good impedance matching at both the bands with the Impinj Monza-4 tag chip used in the design. The measured return losses at 866 MHz and 952 MHz are around -12.25 dB and -12.99 dB respectively. Bidirectional radiation patterns suitable for RFID applications are obtained at both the frequencies. © 2019 URSI. All rights reserved.