Development of an easy equipment for evaluating sleep quality

According to the Taiwan Society of Sleep Medicine reports, one out of every five people has the problem of sleep disorder in Taiwan. Sleep problems are highly prevalent not only elder and the youth. Most of sleep apnea occurred in people with obesity. However, most of the people are not aware of their disease. Therefore, to develop a simple device operated at home for sleep disorder detection is needful. The aim for this study is to implement a simple device for assessing sleep disorder which can be used at home without expensive and complicated equipment. Some signals include snoring signal, oxygen saturation and heart rate variability are recorded. SpO2, photoplethysmography (PPG) and pulse rate were monitored by a pulse oximeter (Nellcor Oximax N-600x). First, the oximetry provided a record pulse signal displayed a real time non-normalized waveform signal. Next, SpO2 display show the hemoglobin oxygen saturation level and continuous recording. Then, pulse rate can be obtained and monitored. AT2020 USB microphone with the features of low-self noise and USB port, is easy to set up and record high quality sound with low power supply are used to acquire the snoring sound. Heart rate variability (HRV) is derived from PP interval time series of photoplethysmography (PPG). HRV with time-domain are computed from PP intervals under time-domain analysis method. SpO2 and pulse rate can be recorded directly when hypoxia.