利用超声多普勒检测涡流的模拟研究

为了优化利用超声多普勒技术检测速度波形，频谱宽度和涡流的精度，可利用短时傅里叶变换和频谱宽度校正的方法检测涡流的情况。从对各种包含频谱宽度和信号功率随时间变化及涡流信息的模拟多普勒信号的分析发现，当采用一定频响的低通滤波器时，短时傅里叶变换可有效地估计血流速度波形和涡流信息的波形。因此这种方法为分析涡流信息提供了一种快速手段。

Simulation Study of Vortex Detection Using Doppler Ultrasound

In order to optimize the accuracy of convective velocity waveform, spectral broadening and vortex estimation using Doppler ultrasound techniques, the short time Fourier transform (STFT) and a bandwidth correction method were used to investigate the detection of vortices. From the experiments of analysis for several simulated Doppler signals which incorportate the bandwidth and power variation and vortex simulation, it was found that the STFT could estimate the convective velocity waveform and vortex effect waveform well when a suitable low-pass filter was used. This method provides a fast tool for the detection of vortices.