Research Of Portable Sleep Monitoring And Analysis System

With the rapid development of electronics, digital signal processing and computer network, the application of electronic measurement has extended to lots of fields and the medical monitor has developed and popularized quickly. Not only the configuration but also the function has changed with each passing day. Sleep Apnea Hypopnea Syndrome (SAS) is a hackneyed disease. There are about 5% people in the world are influenced by SAS and about 90% of those people have not been diagnosed in time. The normal way to diagnose SAS is polysomnography (PSG), but it's expensive and time-consuming. In recent years, portable sleep monitors and analysis systems in diagnosis of obstructive SAS (OSAS) in various levels on the block are not widely used because the cost and most of them needed to be imported.We designed a portable sleep monitor on account of OSAS which can record electrocardiogram, oxygen saturation of blood, pulse rate, pulse wave, breath state and sound of snore chronically. In addition, it can alarm when the respiration is abnormal. Those physiologic data can be stored in a SD card and transmitted to PC for analyzing. The analysis software is designed with LabVIEW which created the report forms of abnormal respiration, and played sound of snore optionally. In addition, the algorithm of Fast Fourier Transform represented the results of frequency analysis,.The system includes voltage unit, signal process unit, alarm unit, serial communication unit, storage unit and other peripheral circuit. MSP430F149 is the core of the portable sleep monitor, which proccessed the signal and controlled the whole circuit. The software includes the system control program and the analysis program on PC. The system control program consists of the main procedure, initialization module, timer interruption module, data processing module, alarm module, serial communication module and storage module. The analysis program includes the main procedure, open file module, data processing module and sound playing module et.al.The monitor can record real time status and analyzing physiologic parameter of the patient exactly for 24 hours at least. With the merits of low power consumption, convenient carrying and low cost, the monitor has high value of practical application in hospital and family monitoring.