The Research And Application Of Non-invasive Continuous Blood Pressure Detection System Based On Pulse Wave

As current economy is rapidly developing,on the one hand,the level of supplies and living standards continue to improve,on the other hand,people's health problems are becoming increasingly prominent.Cardiovascular diseases pose a growing threat to human health.Hypertension is one of the important cardiovascular diseases.Blood pressure is a very important physiological parameters of human body,and it contains various human health information.There are many methods of blood pressure measurement.Usually,indirect measurement is used.And it can be divided into intermittent blood pressure measurement and continuous blood pressure measurement.Coriolis and oscillometric methods are representative of intermittent blood pressure measurement.Although this method is simple and convenient and easy to be operated,the method based on inflated cuff can only measure the blood pressure value at certain moment,and can't achieve continuous blood pressure monitoring.The continuous measurement method of blood pressure provides an important basis for the diagnosis and later treatment of clinical hypertension,and it can monitor blood pressure in real time,which helps prevent hypertension and control the morbidity and mortality of hypertension.The research on non-invasive continuous blood pressure detection has become the focus and trend of current research which based on pulse wave.Based on the previous research on non-invasive continuous blood pressure measurement methods,this paper further studies the pulse wave.Proposing a fusion blood pressure algorithm based on pulse wave transit time and pulse wave multiple characteristic parameters.First of all,designing a non-invasive detection system for continuous blood pressure detection.In this paper,with simultaneous acquisition of electrocardiogram(ECG)signal and photoplethysmography(PPG)signal,through hardware conditioning circuit achieve signal preprocessing.Sending the collected data to the software layer for further processing through serial port transmission.Secondly,extracting feature points of ECG signal and PPG signal.For the defects of soft and hard threshold,an improved threshold function de-noising method is proposed.The experimental results show that this method is effective,and gives better performance than the soft and hard threshold methods.Using differential double threshold method to extract peak points of pulse wave and R wave of ECG,and calculating the value of pulse wave transit time PWTT,and extracting relevant characteristic parameters of pulse wave.Finally,An fusion blood pressure algorithm based on pulse wave transit and pulse wave multiple characteristic parameters is proposed.With the collection and regression analysis of experimental data,obtain a blood pressure calculation model.The experimental results show that the proposed algorithm has good accuracy and the error is within 5mm Hg,which meets the needs of daily blood pressure measurement and can achieve non-invasive continuous blood pressure monitoring.