A Real Time Optical Approach to Acquire and Process the PPG Signal to Extract Physiological Parameters of Human Body

Human pulse signal is a very important signal of human body. By analyzing pulse signal one can determine any kind of abnormality related to human body. Both invasive and non invasive methods are there to acquire pulse signal for analysis. Out of these, non invasive methods are preferred because they are painless and safe. This paper describes the process and steps of acquiring the pulse signal using non-invasive technique and then entire processing and analyzing process is done in LabView (Laboratory Virtual Instrumentation Engineering Workbench), which is a virtual instrumentation technology presently emerging and its use is saving an ample amount of time in acquisition and processing of both analog and digital signals. The acquired signal is called a PPG (Photo Plethysmography) signal because it has been acquired using IR LED as a source and photo diode as a detector to measure the change in volume of blood through finger tip by placing the finger between the source and the detector. The change in intensity of the light received by the detector gives the reflection of the change in volume of blood in the peripheral with each heart pulse. The PPG signal is acquired for various subjects both male and female and for different age category. The detail and proper analysis of these acquired signals gives us the information about the physiological and pathological condition of human body.