The Technique Research Of Dynamic Oxygen Saturation Monitoring

AbstractIn order to meet the need of battleground and the development of community health care, we carried through the re~arch of pulse oximeter.In measuring blood oxygen concentration, some factors which can lead the monitor system to abnormal working. These factors include: the disturbance of environment noise, movement of patients, baseline drift of pulse wave, signal value exceeding range of amplifier and A/D converter, and so on. In order to solve these problems, we carried through research work as below.In hardware design, the following means were applied:1. Applying modulated light to eliminating background light interfering, this also benefits to remove inherent noises of the system;2. Applying auto-baseline regulation circuit to controlling baseline drift of pulse wave;3. Applying adjustable integral amplifing circuit to controlling the range of the signal value;In addition, we studied how to improve structure and shape of fingertip-sensor.In software design, the following arithmetic were applied.1. Applying Moving Average arithmetic to computing oxygen saturation. This method can eliminate effect of finger bend and body movement,ete.2. .Applying LMS self-adaptive filter to eliminating the noises of pulse signal.4.The project is established in new development in signal processing-Independent Component Analysis(ICA), and applying ICA to pulse signal analysis and processing. Proved by experiments Independent Component Analysis(ICA) have much superiority than other methods.