Apparatus and method for estimating missing doppler signals and spectra

In an ultrasound imaging system, a method for processing ultrasound imaging signals, comprising

• receiving a sequence of Doppler signals, said sequence of Doppler signals having at least one gap between a first region comprising data and a second region comprising data;
• determining a first variance and a first set of coefficients for a first autoregressive model in response to said sequence of Doppler signals in said first region comprising data, whereby said first autoregressive model with said first set of coefficients and said first variance approximates said sequence of Doppler signals in said first region comprising data;
• determining a first set of reflection coefficients in response to said first set of coefficients;
• determining a second variance and a second set of coefficients for a second autoregressive model in response to said sequence of Doppler signals in said second region comprising data, whereby said second autoregressive model with said second set of coefficients and said second variance approximates said sequence of Doppler signals in said second region comprising data;
• determining a second set of reflection coefficients in response to said second set of coefficients;
• interpolating said first and second sets of reflection coefficients to determine a new set of reflection coefficients for said gap;
• synthesizing a set of Doppler signal spectra for said gap in response to said new set of reflection coefficients;
• and
• combining said Doppler signal spectra using at least one windowing function for said first region comprising data, said gap, and said second region comprising data.

Apparatus comprising

• means for receiving a sequence of Doppler signals, said sequence of Doppler signals having at least one region comprising data and at least one gap;
• means for determining a first set of parameters of a Doppler signal model in response to said sequence of Doppler signals, whereby said Doppler signal model approximates said sequence of Doppler signals in said region comprising data;
• means for determining a second set of parameters of said Doppler signal model, responsive to said first set of parameters, for said gap;
• means for synthesizing a set of Doppler information for said gap;
• and
• means for combining a set of Doppler information for said region comprising data with said set of Doppler information for said gap.

Apparatus comprising

• means for receiving a sequence of Doppler signals, said sequence of Doppler signals having at least one gap between a first region comprising data and a second region comprising data;
• means for determining a first variance and a first set of coefficients for a first autoregressive model in response to said sequence of Doppler signals in said first region comprising data, whereby said first autoregressive model with said first set of coefficients and said first variance approximates said sequence of Doppler signals in said first region comprising data;
• means for determining a first set of reflection coefficients in response to said first set of coefficients;
• means for determining a second variance and a second set of coefficients for a second autoregressive model in response to said sequence of Doppler signals in said second region comprising data, whereby said second autoregressive model with said second set of coefficients and said second variance approximates said sequence of Doppler signals in said second region comprising data;
• means for determining a second set of reflection coefficients in response to said second set of coefficients;
• means for interpolating said first and second sets of reflection coefficients to determine a new set of reflection coefficients for said gap;
• means for synthesizing a set of Doppler information for said gap in response to said new set of reflection coefficients;
• and
• means for combining said Doppler information using at least one windowing function for said first region comprising data, said gap, and said second region comprising data.