The Research Of Continuous Blood Pressure Measuring Based On The Reflective Pulse Wave

Blood pressure is the lateral pressure to the blood vessel wall in the state of the heart topump blood.The Changes of blood pressure can reflect the state of health and vessel, is animportant physiological indicators of human cardiovascular disease. The blood pressure willchange by the body’s menstrual cycles, mood change, external affect. blood pressure willobviously changed in the rapid change environment. Traditional blood pressuremeasurements are usually carried a single measurement or intermittent measurement, thismeasurement does not make sense on the early prevention of cardiovascular disease. Only thecontinuous measuring blood pressure is important in the home health care and clinicalcardiovascular disease diagnosis.Now we know the blood pressure methods that has muchdeficiencies,some equipment is so complicated、calls expensive、is strict in the mensuringaccuracy. Using some methods to measure blood pressure for a long time measurement. Willbe suffering.So we propose a continuous measurement system based on the reflection ofpulse wave of non-invasive blood pressure.Based on reasearching traditional PPG blood pressure measuring,we propose a newmethod based on the reflective dual photoelectric volume pulse wave of non-invasive bloodpressure.Established the measuring model based on the reflective PPG.and achived themeasurement of the pulse wave、digital signal processing and PTT. proposed a PTTcalculationg method based on PTT.We verified that the method is feasible based on thereflective PPG theory. The main tasks and results of this dissertation are summarized as following.1、Achived the PPG dual signals based on the Software and Hardware platform. TheTI’s low-power16bit MSP430F149microcontroller is hardware’s core.The AD of theMSP430F149complished AD converter.Designed We designed the arm Dual PPG signalphotoelectric detection probe, based on the Lambert-Bill theorem. Software platformcompleted the pulse wave filterring、extracting the pulse feature and calculating the bloodpressure、storaging the data、displaying wavefor based on the Matlab。2、The pulse wave is eliminated noise, based on the Multi-stage digital filter andmedian filter.The PPG is weak Human physiological signals. It is subject to themeasurement of environmental impact. Pulse waves are believed to have greater noise andinterference. The design for the spectral distribution and energy distribution characteristics ofthe pulse wave signal, on the basis of the analog low-pass filter, digital filter and median filterto achieve pulse wave signal noise filtering and baseline drift removal.3、Pulse wave feature point extraction and the calculation of pulse wave propagationtime.With the same one and, the pulse wave shape and amplitude is stable,in a short time.On this basis, using the threshold method of pulse wave peak detection,and taking advantageof the peak feature points to calculate the PTT, and calculating the arterial blood pressure.4、Designing the interactive interface based on the Matlab. Interactive interfacedesign platform based on Matlab.Using Matlab to achive the pulse wave digital signalprocessing、data calculation、data storage、wave display and so on;Designing the GUI platformand real-time measuring the blood pressure.5、Verifing the system,Correcting the system measuring error,by the high-precisionblood pressure measuring instrument. the error bringed by Individual different to Improvesystem versatility and promotion.