Extracting Motional Information from the PhotoPlethysmography Using Reconstruction of the Wavelet Transforms Modulus Maxima

A movement during measurements can generate motion artifacts in photoplethysmography(PPG) signals. The motion artifacts reflect some information of tester´s motion. If we can extract the relevant information from these interferences, it probable will be a new information collection method for portable physiological monitor. This paper first analyzes the relationship between the motion artifact and the PPG signals form the Beer-Lambert law. Then, compare the influence of PPG signals by different direction of movement. Finally, extract the information of motion through the reconstruction of wavelet transforms modulus maxima. Through compares the extracted signal and the real motional signals collected by accelerometer (ACQ), two signals have certain relativity. The extracted signal can basically reflect the tester´s movement. It will be a new way of community and athletes medical care.