Passive and Flexible UHF RFID Tag for Body-Worn Applications

There is a great interest in epidermal devices that provide comfort to users. In this work, an RFID tag for on-body applications on a polyimide substrate was proposed. The tag consists of a low-profile flexible substrate that conforms to the body's curvature, allowing comfortable monitoring of physiological functions. The passive tag has a total dimension of
$112.6\times 26.6\ \text{mm}^{2}$
. It is composed of a folded dipole antenna, in which two Complementary Split Ring Resonator (CSRR) cells were incorporated to improve its performance in proximity to the body, and the Monza® X-2K Dura chip from Impinj®. According to the simulation results, its maximum read range is 3.21 m. Two experiments were carried out: one without the presence of the human body and another with the tag on the abdomen of a volunteer. The maximum read range achieved in the first configuration was 1.89 m, and in the second configuration, it was 1.10 m.