Discrete Time Estimation of the Mean Doppler Frequency in Ultrasonic Blood Velocity Measurements

A new Doppler frequency estimator operating in the discrete time domain is derived from an analysis of the Doppler signal statistics. It is shown that the estimator gives a nearly unbiased estimate of the mean frequency of the signal spectrum, regardless of the spectrum shape. The discrete time implementation gives the advantage that, under specified conditions, the range-velocity product of a pulsed Doppler velocity meter can be increased.