Optimized circular RFID tag antenna achieving extended detection range on metallic surfaces

Abstract

In this paper layout of long detection range radio frequency identification tag antenna mountable on metallic surface is presented. This tag antenna layout consists of two non-connected L-shaped load bars and two sectorial patches electrically connected through seven pairs of vias and conducting rear-plane to form a loop antenna. This proposed tag antenna can be tuned in wide range for impedance matching and introduces circular polarization. The tag antenna characteristics are also measured on metal plate. The results show that maximum detection range of the specimen, placed on metallic plate found to be 8.4 ms. The measured 10 dB bandwidth of circular tag antenna is 17 MHz (906–923 MHz) with simulated 3 dB axial ratio bandwidth of 13 MHz. This circular tag antenna is simulated with 4 W EIRP reader. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.