| Pulse wave can tell us a lot of physiological information, such as pathophysiological information of cardiovascular system. Therefore, measurement and information analysis of pulse wave can help us to obtain an understanding of body's physiological health condition, providing a vital guidence for prevention and clinical diagnosis and treatment of cardiovascular diseases. However, the collection of high quality pulse waves and effective ways of disposing them played a decisive part in measurement and analysis. Based on existing pulse wave measuring and signal disposal methods, this paper, innovatively taking advantage of virtual instrument and its relevant technology, furtherly studied signal disposal methods. In additonal, through theories associated with obtaining cardiovascular parameter by noninvasive pulse wave, a practical cardiovascular data measuring system based on virtual instrument, was designed .This subject mainly included the followling several aspects:1. Through comparison, a collection circuit for pulse signals was built successfully, and by taking advantage of DAQ data collecting card from NI company and labview, a multi-channel physiological signal acquiring and storage system was developed. This system can collect and save multiplexing pyschological signals simultaneously, and parameters of sampling rate, sampling time, data collection methods and saving paths can all be set with great commonality.2. In the process of pulse signals denoising, comparing a lot of experiments, the conclusions can be reached: for the average 300Hz sampling rate physiological signals (pulse signal, electrocardio signal), when given the denoising processing, mean filtering in module 3 had the least impact on the amplitude and phrase of original signal, the effect of which is the best.3. When taking the single-period recognition of pulse signal, difference threshold algorithm was employed, which greatly solved the problem of omissive recognition for first and last pulse data. Through experimental verification, we found that this method can accurately identify the single-period of various pulse signal, and even under severe disturbance of baseline drift or high frequency noise, this method can also identify accurately. During identification, the influence of pulse signal sampling rate is little.4. Interpolation fitting method was used for the baseline adjustment of pulse signals. Through experimental verification, we found that this method can effectively remove baseline drift of various pulse graphs. What's more, the broken line of baseline drift can be drawn, which to some extent provided reference and basis for the study of the reasons for the occurrence of baseline drift.5. During the process of collecting the pluse eigenvalue, in order to mark the featuring points like dicrotic notch and dicrotic wave, second derivative methods was used. Through experimental verification, we found that whether the two points were obvious or not, this method can accurately locate the position. In additional, we also observed that this method can also possibly be used for identifying very unobvious pre-dicrotic wave. When selecting representing pluse eigenvalue, K wave-chose way was used. Three most representing pluse eigenvalue were selected for conjoint analysis, contributing to more comprehensive and effective reveal of the pulse information.6. By taking advantage of theories associated with obtaining cardiovascular parameter by noninvasive pulse wave, we designed a practical cardiovascular data measuring system which was based on virtual instrument. Comparing this system with like products, we found that the results were correct, and this system can be applied in community health care and home health care.
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