A PPG-based physiological sensing system with a spatio-temporal sampling approach towards identifying and removing motion artifacts from optical signals
The present invention pertains mainly to the fields of fitness and/or sport performance by enabling robust and accurate determination of physiological parameters, including, but not limited to, heart rate and breathing rate as indicator of physical exertion or intensity during exercise. In one embodiment, the present invention is a PPG-based physiological sensing system employing a spatio-temporal sampling approach towards identifying and removing motion artifacts from optical signals received from a wearable optical sensing device in real-time and during various states of physical activity. The invention comprises a wearable optical sensing device capable of sensing and transmitting optical signals representative of physiological parameters to a remote electronic device. The wearable optical sensing device comprises an optical sensing unit with a light-emitting and light-detecting module for measuring blood volume changes caused by expansion and contraction of the small blood vessels in the skin and underlying tissue during the cardiac cycle. The spatial arrangement and temporal sampling configuration (sequence) of the system subsequently allows for a common absorption point to be determined mathematically for each multi-channel sampling period, thereby obtaining an instantaneous optical measurement at different positions on the propagating pulse wave.
