| 摘要 |
A spectral tissue Doppler processor for an ultrasound system produces Doppler phase shift estimates of sequences of signal samples from a sample volume with a short-lag autocorrelator . The autocorrelation products are summed and an arc tangent taken of each sum to produce angle estimates . The angle estimates, which are proportional to the tissue motion velocity, are plotted, smoothed, and displayed as a spectral tissue Doppler display. The angle estimates are also used to produce the audio Doppler signal which is frequency-adjustable by a user. The spectral Doppler display exhibits good time and velocity resolution for motion which is less than that of blood flow such as myocardial motion. Major causes of blurring, unevenness, and distortion are reduced or eliminated. |
