Implementation Of A Four-channel Reflectance-mode PPG Signal Detection System

With the development of Electronic Science and technology,the application of embedded system has penetrated into every industry,such as network communication,consumer electronics,industrial control,especially in the digital medical field has been widely used.The combination of embedded technology and bio-medical signal processing technology is the inevitable trend of the development of digital medical equipment in the future.Non invasive detection of physiological signals such as heart rate,blood pressure,blood oxygen saturation,hemoglobin and so on,has important significance in surgery,blood transfusion,blood donation,nutrition survey and so on.Traditional detection methods,the detection step complex(blood pressure measurement),or broken skin blood(hemoglobin concentration detection),not only on subjects caused physiological and psychological burden and does not continuous detect the change of hemoglobin concentration.Pulse wave signal contains rich in human physiological signal information,including heart rate and oxygen.The light capacitance volume pulse wave(photoplethysmographic,PPG)signal makes extraction of the physiological signal detection without a convenient become a reality,so the use of PPG signal provided from heart rate and oxygen has been widely used.For using the photo electric volume pulse wave detection of hemoglobin concentration is still in the research stage,this paper aims to study photoplethysmography pulse wave trace notation of noninvasive pulse wave detecting technique and its implementation four road light capacitor product pulse signal acquisition system based on.Major work and results include:Further researching in the heart rate,oxygen saturation,hemoglobin concentration of physiological signal detection theory and technology development,noninvasive detection of intelligent medical has a broad market prospect.introduced noninvasive detection technology of optical based on the PPG and physiological learn basic knowledge,for the core device that experimental platform used,the principle of the devices were described in detail.On the basis of the theory above,establishing the four way PPG signal acquisition system platform,mainly including: the development environment based on arm Cortex-M3 processor,and the related peripheral circuit analysis;design and production sensor probe;design and implementation of analog front-end signal acquisition and processing module,data acquisition,data storage and data transmission module to realize.Collection 21 cases of clinical data using of the system,which provide reliable data for extraction for PPG signal processing and physiological information.In this paper,the realization of the four PPG signal detection system is expected to function,and has a high stability and reliability,the paper's research has achieved the expected results.