ZEROECG: Zero-Sensation ECG Monitoring By Exploring RFID MOSFET
Wenli Jiao, Ju Wang, Xinzhuo Gao, Long Du, Yanlin Li, Lili Zhao, Jin Qi, Dingyi Fang, Xiaojiang Chen · IEEE Transactions on Networking · 2024
ECG monitoring during human activities is crucial since many heart attacks occur when people are exercising, driving a car, operating a machine, etc. Unfortunately, existing ECG monitoring devices fail to timely detect abnormal ECG signals during activities due to the need for many cables or a sustained press on devices (e.g., smartwatches). This paper introduces ZeroEcg, a wireless, battery-free, lightweight, electronic-skin-like tag integrated with commodity RFIDs, which can continuously track a user's ECG during activities. By exploring and leveraging the RFID MOSFET switch, which is traditionally used for backscatter modulation, we map the ECG signal to the RFID RSS and phase measurement. It opens a new RFID sensing approach for sensing any physical world variable that can be translated into voltage signals. We model and analyze the RFID MOSFET-based backscatter modulation principle, providing design guidance for other sensing tasks. Real-world results illustrate the effectiveness of ZeroEcg on ECG sensing.