【摘要】 超声多普勒血流信号的时—频分布可以作为诊断血管疾病的重要依据 ,由于多普勒血流信号是窄带且非平稳的 ,传统的短时傅立叶变换方法进行分析时容易产生较大的误差 ,小波变换具有多分辨率的特点 ,其时间—频率窗可以自动调节 ,能较精确地实现对非平稳信号的分析 ,通过对模拟的超声多普勒血流信号的分析表明 ,小波变换可以为超声多普勒信号的分析提供一个有效的方法·更多还原

【Abstract】 The time frequency distribution of the Doppler Ultrasound blood flow signal is an important basis for diagnosing vein sickness. Because the Doppler blood flow signal is the non stationary and narrow band signal, the traditional Short time Fourier Transform (STFT) method for Doppler signal analysis will bring big error easily. The multi resolution approach that characterizes the wavelet method provides a way to catch the information at different resolution levels. Wavelet Transform (WT) has a flexible time frequency window to adapt to any time frequency range, which makes wavelet transform appropriate to analyzing non stationary signal exactly. Analyzing the Simulated Doppler Ultrasound blood flow signal proves that, Wavelet Transform is a valid approach for analyzing Ultrasound Doppler Signal.更多还原