AMSM 2019, Incheon, Korea
October 16 - 19, 2019 (Tue. - Fri.), Sheraton Grand Incheon Hotel
Wireless Powered VOC Sensor Based on Wi Fi Energy Harvesting Metamaterial with i-TPU
Wonwoo Lee, Heejoo Park, Hyunseung Jung, So Young, Kim, Do Hwan Kim, and Hojin Lee
Abstract
In this paper, we propose a novel wireless powered VOC sensor system based on energy harvesting metamaterial combined with ionic thermoplastic polyurethane (i TPU) gas sensing channel at microwave frequency . The sensor consists of the SRR, rectifier circuit t o harvest the RF energy by converting electromagnetic energy into DC voltage, and i TPU gas sensing channel to detect VOC with the variation of resistance. For the practical wireless sensing system, we utilized widespread and easily accessible commercial 2 .4 GHz Wi Fi source as external electromagnetic wave energy, and the energy harvesting metamaterial was designed and optimized to resonate at 2.4 GHz. When i TPU was exposed to VOC , the diffusivity of ionic liquid (IL) increases leading to decrease of the resistance of i TPU that can be identified with the differential harvested energy induced from variation of resonance property for the energy harvest ng metamaterial sensor . As a result, by analyzing the differential harvested energy , the proposed sensor c ould provide the highly sensitive wireless VOC sensor system without bulky and complicated measurement system offering great accessibility and simplicity for the practical sensor applications Also, the wireless powered VOC sensor showed high stability and repeatability representing the rapid restoring to the initial resistance value of the i TPU gas sensing channel. Finally , it is expected that the proposed system can be applied to not only for VOC sensors but also for dynamic environmental sensing systems
