A modified parametric estimation of ultrasound Doppler velocity

A new recursive least square (RLS) method is here used to compute complex ARMA in a two-step Doppler flow velocity estimate. Compared with the classical RLS case, this method provides better results, and needs few additional computations. This method is applied to the Doppler ultrasound flow velocity measurement through frequency estimates. Thus, after the computation of the complex AR parameters of the Doppler analytic signal in a first step, we propose in a second step, a direct velocity measurement by using these parameters, without an explicit computation of the power spectral density (PSD). This method compared with the PSD peaks detection is more accurate and almost independent of the signal-to-noise ratio.