Wearable devices are becoming more and more popular in recent year. Many of them are embedded with powerful processor and sensors which could enable a vast of new applications. One issue that researchers and engineers are concerned about is how to leverage the power of wearable devices to monitor our physical conditions so that we could use it to provide guidance to maintain a healthy life. Heart rate is one of the most significant vital sign of human which is tightly related to both of our physical and mental condition. Reflective wrist photoplethysmograph (PPG), obtained by a watch or wristband, can provide a natural and unconstrained way for daily life heart rate monitoring. However, reflective wrist PPG often suers from poor signal quality and various distortions due to dail...[ Read more ]

Wearable devices are becoming more and more popular in recent year. Many of them are embedded with powerful processor and sensors which could enable a vast of new applications. One issue that researchers and engineers are concerned about is how to leverage the power of wearable devices to monitor our physical conditions so that we could use it to provide guidance to maintain a healthy life. Heart rate is one of the most significant vital sign of human which is tightly related to both of our physical and mental condition. Reflective wrist photoplethysmograph (PPG), obtained by a watch or wristband, can provide a natural and unconstrained way for daily life heart rate monitoring. However, reflective wrist PPG often suers from poor signal quality and various distortions due to daily life motion artifact. In this thesis, we analyze the influence of motion artifact on reflective wrist PPG signals, and propose a method to extract reliable heart rate from such distorted PPG signals. The proposed method consists of adaptive filtering, heart rate selection, and motion identification. Experimental results show that our proposed method can generate reliable heart rate values from wrist PPG signals with different types of motion artifact.