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在绝大多数连续波多普勒血流测量系统中，通常采用一个高通德波器来滤除由固定目标和血管壁产生的强反射信号．本文从理论上推导出引入高通滤波器会导致血流平均速串估值们高．由于高通德波器对不同频率信号在幅度和频率上有不同的影响，因此会相应地引起多普勒信号不同分量产生不同的相移（时移），对血流动态谱会有一定影响．通过计算机仿真试验证明：当信号通过滤波器时，如果幅度保持不变，那么高通滤波器引起的信号非线性相移（时移）对血流动态港几乎没有影响。
In most continuous wave Doppler blood flow measurement systems, a high-pass filter is often used to filter out strong reflection signals produced by the fixed target and the vessel wall. In this paper, it is theoretically deduced that the introduction of a high-pass filter leads to high estimates of the average velocity series of the blood flow. Due to different influences on the amplitude and frequency of the signals with different frequencies, the high-pass filter will correspondingly produce different phase shifts (time shifts) of different components of the Doppler signals, which will affect the blood flow dynamic spectrum to a certain extent. Computer simulations prove that when the signal passes through the filter, the signal non-linear phase shift (time shift) caused by the high-pass filter has almost no effect on the dynamic port of blood flow if the amplitude remains the same.