Maximum likelihood frequency tracking of the audio pulsed Doppler ultrasound signal using a Kalman filter

Accurate estimation of velocity from the audio Doppler signal is important in the study of disease. The paper addresses this problem by considering the application of maximum likelihood as the basis for frequency tracking using a Kalman filter. The effectiveness of the algorithm in velocity estimation on both test signals and clinical data is discussed. This is particularly important in tracking of the oscillations which occur in the deceleration phase of the cardiac cycle.