Anti-Metal Dipolar Tag Antenna With Integrated Huygens’ Metaelement for Gain Enhancement

Abstract

A Huygens’ metaelement (HME) is integrated with a grounded dipolar tag antenna, which is meant for anti-metal applications, for enhancing the tag’s realized gain for the first time. Here, the HME is top loaded onto the antenna structure for shaping its radiation beam so that a higher directivity can be achieved. The characteristics of the element are analyzed by applying a unit element with periodic boundaries. It can achieve a good transmissivity of $\vert $ $\mathrm{S}_{21}\vert \gt -0.09$ dB with low loss. Incorporating the HME with the dipolar tag antenna has successfully enhanced the realized gain by 3.02 dBi, without affecting the frequency or impedance performances much. Despite its compact footprint of 50 mm $\times 50$ mm ( $0.1446\lambda \times 0.1446\lambda $ ) and low profile of 2.01 mm ( $0.0058\lambda $ ), the proposed integrated dipolar tag can achieve a consistent read range of approximately 8 m, irrespective of the size and shape of the backing metal.