A Wireless Power Transfer System (WPTS) Using Misalignment Resilient, On-Fabric Resonators for Wearable Applications

In this paper, we demonstrate a fabric integrated, near-zone WPTS , which uses a newly developed misalignment resilient antenna element for inductive power transfer for wearable applications. The antenna consists of a combination of electric and magnetic coupling in the near field to achieve high power transfer efficiency (PTE) even under misalignment. For fabric integration, the proposed antenna and rectifier system was fabricated on a textile substrate by using conductive thread embroidery. We report the PTE of the developed antennas variation with different misalignment cases. For lateral misalignment, the proposed antenna exhibited an average PTE of 85% for lateral movements within 10 cm. Furthermore, antennas exhibited an average PTE of 70 % for elevation and 60 % for azimuthal misalignment cases. These results are compared with circular loop resonator illustrating the improvements in the PTE. Using this antenna element,power harvesting system and its resiliency to misalignment is also demonstrated.