Breathing motion artifact cancellation in PPG-based heart rate sensing

We have developed a photoplethysmography (PPG)-based heart rate (HR) sensor [1], which is equipped with two sensors; one is a normal PPG sensor and the other is a motion artifact sensor. In the PPG-based HR sensor, applying an adaptive filter algorithm for the outputs from the two sensors, it can effectively cancel motion artifact induced by vigorous exercise. Breathing motion is also one of the main sources of artifact in PPG-based HR sensing. In this paper, we evaluate the cancellation performance of breathing motion artifact by the PPG-based HR sensor in experiments using five subjects.