TITLE:
Development of a Printed Coil for Wirelessly Charging a Tracking Elderly Patch
AUTHORS:
Bouchta Hajjine, Christophe Escriba, Samuel Charlot, Anne Hemeryck, Julien Roux, Sabeha Fettouma Zedek, Jean-Yves Fourniols
KEYWORDS:
Wireless Charger, Receiving Coil, Tracking Patch, Cleanroom Process
JOURNAL NAME:
Wireless Engineering and Technology,
Vol.7 No.2,
April
19,
2016
ABSTRACT: Monitoring systems for elderly require a compromise between reduced size and
operational autonomy. The latter to get a system as independent as possible and
to fit with our application needs for daily use. Our patch is developed as a surveillance
system for old people; we chose to equip it with a wireless charging system for
greater ease of use, imperceptible in the everyday life and waterproofing. This
paper presents the development of a printed receiver coil to be integrated in a
wireless charger to be used in an elderly tracking patch. The proposed design is
validated using simulation that presents a good agreement with measurement results:
Simulation (@150 KHz: L = 10.74 μH; R = 3 Ω) and Measurement (@150 KHz: L = 10.8
μH; R = 3.16 Ω). The receiver coil is elaborated on a polyimide substrate in the
cleanroom of our laboratory LAAS-CNRS (Laboratory for Analysis and Architecture
of Systems-National Center for Scientific Research) and a PCB (Printed Circuit Board)
charger prototype is fabricated to test its performances before the integration
of the wireless charging property in the tracking patch. The proposed coil presents
a good compromise between small size and efficiency. For a charging current of 7.5
mA, this coil can ensure the recharging of the patch up to a distance of 4.8 mm
between the Qi transmitter and receiver which is more than enough for our application.