Study Of The Application Of Ballistocardiogram Signal Based On Piezoelectric Thin Film Sensor

Ballistocardiogram is obtained by pressure sensors caused by cardiac signal of the gravity of the human body,and is a kind of electrode contacts,free,non-invasive cardiovascular function in monitoring technology.The signal can be used to observe the working state of the heart in real time,and to monitor the physical status of the patients with sudden heart disease and cardiovascular diseases timely.So theses uses the BCG as the research object to carry on the applied analysis.Theses describes the design of a piezoelectric film BCG signal acquisition system based on the system,according to the collected information,the applied research in two aspects: the first is the detection of BCG in the feasibility of the application of heart rate variability aspects,then studied the correlation between BCG and ECG.The main research and work of theses are as follows:(1)It designed a sensor based on piezoelectric thin film of BCG signal acquisition system,the system by means of a charge amplifier,low-pass filter circuits,voltage amplification circuit and voltage lifting circuit of sensor signal for preliminary processing.For ease of use,by a microprocessor after collecting the signal wirelessly to the PC,the signal display and heart rate calculation.(2)The wavelet algorithm is used to denoise the obtained BCG signal and ECG signal.And through the correlation analysis between BCG and ECG,we found the waveform detail of BCG signal.The work done is to lay the theoretical basis of combining the use of two signals to evaluate cardiac function and cardiovascular disease.(3)By synchronous capturing the ECG and BCG signal of some testers,I compared the time-domain,frequency-domain and nonlinear’s characteristic values of the two signals.The correlations and significant differences of HRVBCG parameters and HRVECG parameters were checked,thereby we can test and verify the feasibility of applying the BCG in HRV.