Characterization of embroidered dipole-type RFID tag antennas

Wearable RFID tags and wireless sensors can be used for on-body and human monitoring applications. Embroidery with conductive thread provides compelling means for the fabrication of seamlessly garment-integrable antennas for wearable tags and wireless sensors. In this paper, we present the fabrication of fully assembled tags based on embroidered dipole-type antennas. The prototype tags achieve 5.5-to-7 meters read range. Moreover, we present a method for estimating the effective conductivity of the embroidery pattern, which depends on the sewing pattern and the stitch density. This will enable the judicious optimization of embroidered tag antennas using electromagnetic simulation tools.