Open AccessCommon‐mode noise cancellation circuit for wearable ECG
Author(s) -
Noro Mutsumi,
Anzai Daisuke,
Wang Jianqing
Publication year - 2017
Publication title -
healthcare technology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.45
H-Index - 19
ISSN - 2053-3713
DOI - 10.1049/htl.2016.0083
Subject(s) - wearable computer , noise (video) , resistor , computer science , electromagnetic interference , interference (communication) , common mode signal , common mode rejection ratio , voltage , electrical engineering , electronic engineering , active noise control , wearable technology , mode (computer interface) , telecommunications , noise reduction , engineering , amplifier , operational amplifier , artificial intelligence , embedded system , bandwidth (computing) , channel (broadcasting) , transmission (telecommunications) , analog signal , image (mathematics) , operating system
Wearable electrocardiogram (ECG) is attracting much attention for monitoring heart diseases in healthcare and medical applications. However, an imbalance usually exists between the contact resistances of sensing electrodes, so that a common mode noise caused by external electromagnetic field can be converted into the ECG detection circuit as a differential mode interference voltage. In this study, after explaining the mechanism of how the common mode noise is converted to a differential mode interference voltage, the authors propose a circuit with cadmium sulphide photo‐resistors for cancelling the imbalance between the contact resistances and confirm its validity by simulation experiment. As a result, the authors found that the interference voltage generated at the wearable ECG can be effectively reduced to a sufficient small level.