Sleep Apnea Syndrome Automated Monitoring And Analysis System

In this dissertation, a research has been made on Pulse Oxygen Saturation detecting module and the pre-amplifier circuit for detecting respiration, which will be used in Sleep Apnea Syndrome (SAS) automatic monitoring and analysis system. The paper includes:1, the study on principle of SpO₂ detecting method had been made, and a new method not using extremum but minimum-maximum was brought out. This method was not limited to one pulse period which simplify the process of pulse signal, and enhance the reliability of the result.2, the detecting circuit of SpO₂ has been analysed, which is exploringly digital time divide modulating measuing scheme. The red light signal, infrared light signal and enviroment light signal were processed in digital domain.The noise of these signals was suppressed by digital filters.3, one-board relization of SpO₂ detecting had been studied. A new approach utilzing SOPC was put forward. The SOPC system in this paper solved the problems of signal processing and IOs' control in high integration. It can be easily inregrated in Sleep Apnea Syndrome Monitoring and Analysis System.4, the pre-amplifier circuit for detecting respiration was designed, choosing thermometry method, with NTC temperature sensor and measuring bridge. What's more, we've designed a baseline stabilization circuit with good effect.Finally, based on the work above, the prototype machine was been debugged and calibrated. The paper was end with conclusion. Some ideas were put forward for next step work.