Multiple switching light sources based motion artifacts reduction in reflectance photoplethysmography

Abstract

We proposed a technique to eliminate motion artifacts by subtracting the two green signals with different light intensity from single green LED. We used green LED light source with a photodetector to obtain the PPG signals from the wrist. We showed that the signal subtraction with different light intensity from the same light source reduced motion artifacts, and the clean PPG signal was remained. Performance comparison was carried out in five different scenarios: stationary state, fingers movement, gripping, up-down vertically bending and left-right horizontally swinging conditions. As expected, we obtained suitable clean PPG signals in all conditions using our proposed technique.

Motion Artifact Removal Techniques for Wearable EEG and PPG Sensor Systems

“…For motion artifact reduction methods without learningbased systems, analyses on time domain (Figure 11A) and frequency domain (Figure 11B) are regarded. A signalsubtraction method with two PPG channels is used for the time-based analysis (Lee et al, 2016). Two PPG channels have different light intensities, and thus PPG signals and motion artifacts obtained from the two channels are different, respectively.…”