Respiratory Events Estimation From PPG Signals Using a Simple Peak Detection Algorithm

The use of PPG has gradually become a popular method for measuring vital signs of individuals. Having compact size sensor, being low-cost and its ease of use have all contributed widely to its success. For instance, PPG is used to measure the pulse rate and blood oxygen level but unable to measure the respiration rate. To measure the respiration rate, breath needs to be annotated manually or a specific device such as Pneumograph needs to be used. Until today, there have been several algorithms introduced to estimate the respiration rate from the PPG signals. However, none of the introduced algorithms have been able to provide enough information about the specific times that these respiratory events had been occurred. In other words, it is unclear that at which point in time the respiratory events happened. In this research, we propose a simple yet effective approach of extracting all respiratory events from the PPG signals.