Nonlinear Analysis Of Fetal Instantaneous Heart Rate

The status of fetal health is mainly controlled by the central nervous system. The reserve capacity of the central nervous system is very weak and it is easily reflected by the oxygen deficiency. The fetal heart rate is the reflection of the regulate adjustment of the central nervous system. So monitoring the fetal instantaneous heart rate and analyzing the changing state of it is the simplest and effective method to diagnose the fetal status.The content of this thesis mainly includes three parts:First: Acquiring the fetal heart sound signal. The fetal heart sound signal is obtained by ultrasonic equipment. This part mainly introduces a method of how to utilize the sound card and combining Matlab language to input the fetal heart sound signal into the computers. It is in order to carry on further analysis and treatment.Second: The acquisition of signal of fetal instantaneous heart rate. Three kinds of methods are introduced in this part. They are the classical autocorrelation algorithm,wavelet analysis algorithm and the maximum value of wavelet module algorithm. The results of experiment indicate that the method of the maximum value of wavelet module arithmetic can eliminate the noise of signal effectively and then obtain a more accurate fetal instantaneous heart rate.Third: The analysis of signal of fetal instantaneous heart rate .After obtaining the curve of accurate fetal instantaneous heart rate, the next central step is to analyze the signal. In this part, utilizing Welch algorithm to analyze the power spectrum of fetal heart rate at first. From the characteristic of the power spectrum,it can be found that power...