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脉冲多普勒信号的频谱宽度可作为诊断血管疾病的一个重要参数．使用传统的短时快速傅里叶变换进行信号分析时，窗函数和信号非平稳性的展宽效应将导致频谱宽度估计值过大．为准确估计这一参数，提出了一种通过计算展宽函数频谱宽度并进行校正的方法．对已知特性的模拟脉冲多普勒信号的分析发现，这种方法降低了频谱宽度估计的误差，而且由于该方法仍然基于快速傅里叶变换，所以便于实时实现．
The spectral width of pulsed Doppler signals can be used as an important parameter in the diagnosis of vascular disease. When using the traditional short-time fast Fourier transform for signal analysis, the broadening effect of window functions and signal nonstationarity will result in an oversized spectral width estimate. In order to accurately estimate this parameter, a method of calculating the spectral width of the broadening function and correcting it is proposed. The analysis of the simulated pulsed Doppler signals of known characteristics shows that this method reduces the error of the spectral width estimation and is easy to implement in real time because the method is still based on Fast Fourier Transform.