Real-time obstructive sleep apnea detection based on ECG derived respiration signal

It is known that ECG signal are strongly affected by the chest motion of respiration. We utilize this property and derive a respiration related signal with respect to the change of R wave area, and then match the derived signal to the time axis. We discovered that during the apnea section, a lower frequency component compared to the respiration frequency is observed. With the presence and absence of this lower frequency modulation on the ECG signal, we propose a real-time detection method to differentiate the apnea section and normal breathing section in the duration of sleep.