The Doppler velocity waveform.
نویسندگان
چکیده
Figure 1. Spectral analysis and the Doppler display. The fast Fourier transform (FFT) separates the Doppler signal into its component Doppler-shift frequencies and determines the amplitude at each frequency. Most ultrasound machines calculate Doppler-shifted frequencies over 5 msec increments and convert this to velocity information. These velocities are then displayed in a bin whose brightness is proportional to the amplitude of the signal. Spectral Analysis and the Doppler Display
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ورودعنوان ژورنال:
- Echocardiography
دوره 23 6 شماره
صفحات -
تاریخ انتشار 2006