Analysis, Design, and Manufacture of a Compact UHF RFID Tag Antenna for Operating in a Metallic or Non-Metallic Environments

Abstract

A miniaturized tag antenna is presented in this paper, for operating in the RFID UHF American band, in free space or in a metallic environment. The proposed antenna is printed on a single layer FR4 substrate, and designed first to work in a free space. The shape of the π-match allowed us to achieve a good matching between the antenna impedance and that of the chip. The correspondence between simulation results in CST and HFSS pushed us to manufacture a prototype of our tag. After that, we simulated the proposed antenna in a metallic area, by adding a square metal plate separated with the antenna by a foam-layer, in order to test the performance of the tag in this environment. An optimization procedure enabled us to achieve a good performance when operating in metallic surroundings. Finally, we tested the reading range of the manufactured tag. We obtained a good range of about 6.5m. The final design of our proposed tag has a simple structure, a dimension of 51×26,63×0.8 3 and which is reduced by 88,64% compared to the calculated theoretical dimensions of a patch antenna operating at the resonant frequency of 915 MH.