Parallel plate antenna for UHF RFID tags operating over metallic objects

Abstract

New applications for passive UHF RFID systems, such as tagging small and expensive metal objects, impose strict requirements on the size of the tag antenna and the read range of the system. Thus, miniaturized tags that achieve read ranges of several meters are of major interest for these applications. In this contribution, the design of a small antenna to tag metallic items is presented. It achieves a maximum read range of 13.3 meters and its dimensions are 14.3 × 25 × 3 mm3. The proposed design consists in a short-ended parallel plate. It is mounted on a ceramic substrate to obtain the required miniaturization. A comparison with the smallest tag designs found in the literature will be also carried out.