Research On Heart Rate And Respiratory Rate Technology Based On Photoplethysmogram

Heart rate and respiratory rate is an important physiological parameter of human body. Heart rate can be the measure of a man’s heart is normal. Respiration rate can be the measure of a man’s respiratory system is health. The heart rate and respiratory rate is not remain constant, they will be affected by many factors, such as sports, emotional and so on. Compared with the current clinical use electrocardiographic and the carbon dioxide detector method, photoelectric volume pulse wave extracting heart rate and respiratory rate not only get rid of the traditional detection methods’bulky, inconvenient and high cost, but also can continuously detect heart rate and respiratory rate over an extended period of noninvasive.In order to extract the heart rate and respiratory rate from photoplethysmography, this thesis has do some research and analysis on the pulse wave signal. Firstly, the thesis has proposed an method which using the joint time-frequency to achieve the extraction of heart rate. Besides, two methods has been realized to extract the heart rate from pulse wave to make the comparison with the new proposed method. In addition, this thesis presents a method that based on an adaptive decomposition technique extract the respiration rate using time-frequency spectrum. Besides, the exited techniques of digital fillers and continuous wavelet transform are also been used to extract the respiration rate. The thesis also makes the comparison among the methods. Due to the different of heart rate and respiratory rate reference, this thesis has taken the different ways to do the comparison. It has done the analyzed about the extraction algorithms of heart rate from the parameters of the algorithms which produce the effect on itself and the anti-noise and time efficiency among the algorithms. Error detection has been made among the algorithms of extraction the respiratory rate to do the analysis of the accuracy and consistency.The experimental results show that the algorithms that proposed above can realize the extraction of heart rate and respiratory rate from the pulse wave. The analysis results of the algorithms that extracting the heart rate from pulse wave signal have shown that heart rate can be calculated from in different time in the normal condition with small interference. The time domain method and the FFT method have much lower time complexity than the CWT method. FFT method and CWT method have much better anti-noise ability than the time domain method. The result of the analysis of the methods of extracting the respiratory rate show that the method that based on the decomposition spectrum method which the thesis proposed can take the precision of frequency and the precision of time into account, and has good accuracy and consistency too.