Open AccessMiniaturized Self‐Resonant Micro Coil Array with A Floating Structure for Wireless Multi‐Channel Transmission
Author(s) -
Jun Byoung Ok,
Kim HanJoon,
Heo Su Jin,
Kim Jonghyeun,
Yang Jae Hoon,
Kim Seunguk,
Kim Kyungtae,
Jin WooCheol,
Choi JiWoong,
Jang Jae Eun
Publication year - 2021
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.202102944
Subject(s) - antenna (radio) , electromagnetic coil , impedance matching , wireless , electronic engineering , antenna array , computer science , acoustics , electrical engineering , electrical impedance , engineering , telecommunications , physics
Micro size antennas have significant merits due to the small size effect, enabling new device concepts. However, the low‐quality factor (Q‐factor), the large size of impedance matching components, and the poor selectivity of the multi‐array design remain challenging issues. To solve these issues, a floating coil structure stacked on a loop micro‐antenna is suggested. Various floating coil designs are prepared with appropriate matching conditions at specific target frequencies, using an easy fabrication process without the need for additional space. A simple one‐loop antenna design shows a higher Q‐factor than other, more complicated designs. The micro‐sized loop antenna with the 80 µm trace width design exhibits the highest Q‐factor, around 31 within 7 GHz. The 8 different floating coil designs result in high‐frequency selectivity from 1 to 7 GHz. The highest selectivity contrast and WPT efficiency are above 7 and around 1%, respectively. Considering the size of the antenna, the efficiency is not low, mainly due to the good matching effect with the high Q‐factor of the floating coil and the loop antenna. This micro‐antenna array concept with high integration density can be applied for advanced wireless neural stimulation or in wireless pixel array concepts in flexible displays.