Motion Artifact Reduction in Photoplethysmographic Signals using Singular Value Decomposition

Artifact free photoplethysmographic (PPG) signals, obtained with red and infrared (IR) optical sources and detectors are necessary for non-invasive estimation of oxygen saturation (SpO₂) in arterial blood. Movement of a patient corrupts the PPGs with motion artifacts, resulting in large errors in the computation of SpO₂. This paper presents a novel singular value decomposition (SVD) based method to reduce motion artifacts from corrupted PPG signals. Test results on a prototype incorporating the proposed SVD technique show that stable and reliable SpO₂ measurement is achieved even when PPGs are distorted by motion artifacts, thus establishing the efficacy of the proposed method.