Design of wideband RFID tag antenna for metallic surfaces

Abstract

A low-cost wideband antenna for radio frequency identification (RFID) tags mountable on metallic surfaces is presented. A novel proximity-coupled feed structure, in which the direction of the microstrip feedline is orthogonal to that of the resonant length of the radiating patch, is explored to perform simple and wideband impedance matching between an antenna and a tag chip without any additional matching networks. The proposed design is verified by simulation and measurement, which show good agreement.