摘要
目的:针对母亲的活动和胎儿在子宫内的活动都会导致胎心音信号的幅度出现较大波动,传统自相关算法难以准确测量胎儿瞬时心率的问题,提出一种基于短时傅里叶变换的胎心音瞬时心率检测新方法。方法:对胎心音进行短时傅里叶变换,从二维时频图中提取出胎心音特征模板并与目标图像进行归一化互相关匹配,绘制出互相关曲线,根据互相关曲线中的相邻峰值点时间间隔,计算出胎儿的瞬时心率。结果:实验结果表明,该算法的识别准确率比传统算法高5%。结论:该算法克服了胎心音易受噪声干扰的弱点,实现了胎心音瞬时心率的计算,而且还提高了胎心率计算的准确性,为胎心音波形分析和胎心率监护提供了一种新的方法。
Objective To put forward a fetal cardiac sound instantaneous heart rate detection algorithm based on short-time Fourier transform to conquer the signal fluctuations by the motion of the gravida and fetus, Methods Short-time Fourier transform was carried out on the cardiac sound, then the cardiac sound feature template was extracted from 2-d time-frequency diagram. The result of cardiac sound feature template matching the target image was normalized to plot the cross-correlation curve. According to the cross-correlation curve adjacent peaks in the time interval, the instantaneous heart rate of the fetus was calculated, Results Experimental results showed that the algorithm of the recognition accuracy was higher than the traditional algorithm by 5%. Conclusion The fetal cardiac sound instantaneous heart rate detection algorithm based on short-time Fourier transform increases the accuracy of fetal heart rate detection with its vulnerability to the noise eliminated, and thus can be used for the fetal cardiac sound waveform analysis and fetal heart rate monitoring.
出处
《医疗卫生装备》
CAS
2013年第12期10-12,共3页
Chinese Medical Equipment Journal
基金
广东省中国科学院全面战略合作项目(2012B091100279)
关键词
短时傅里叶变换
胎心音信号
瞬时心率
二维时频图
归一化互相关匹配
short-time Fourier transform
fetal cardiac sound signal
instantaneous heart rate
2-d time-frequency plane
normalized cross-correlation matching
