Research on RF Tag Performance on Metal Media and Design of Slotting Tag

Abstract

Passive radio frequency (RF) tags in the UHF and microwave bands have recently drawn considerable attention with their great potential for use in inventory management, parcel and postal tracking. However, much more basic research is needed to increase the range and reliability of a passive RF tag’s radio link, particularly when the RF tag is placed onto a lossy dielectric object or a metallic surface. This paper presents two new useful forms of the radio link budget that describe the power link of an RF tag system when the tag is attached to an object, then the effects of a metal plate to antenna parameters when the antenna is horizontally placed near the plate. Furthermore, according to a series of tests for measuring the performance of an RF tag, relationship between distance from tag to a sheet of copper surface and readability is discovered. Moreover, the magnifying effect of an extra metal layer to readability is found too. Finally, according to the results of experiments, a design method of slotting RF tag which can be used to identify the goods location is proposed. This method can not only eliminate negative effect of metal disturbance, but enhance readability, which considers the convenience for use and manufacture cost as well.