초록 ▼

Embodiments for setting eigenvectors for clutter signal filtering from Doppler signals in an ultrasound system are disclosed. In one embodiment, the ultrasound system includes: a Doppler signal acquisition unit configured to transmit and receive ultrasound signals to and from a target object to acqu

Embodiments for setting eigenvectors for clutter signal filtering from Doppler signals in an ultrasound system are disclosed. In one embodiment, the ultrasound system includes: a Doppler signal acquisition unit configured to transmit and receive ultrasound signals to and from a target object to acquire first Doppler signals; and a processing unit configured to compute a plurality of eigenvectors by using the first Doppler signals and form second Doppler signals corresponding to directions of the computed eigenvectors, the processing unit being further configured to compute component values of the second Doppler signals and set eigenvectors for clutter signal filtering among the plurality of eigenvectors by using the computed component values.

대표청구항 ▼

1. An ultrasound system, comprising: a Doppler signal acquisition unit configured to transmit and receive ultrasound signals to and from a target object to acquire first Doppler signals; anda processing unit configured to compute a plurality of eigenvectors by using the first Doppler signals and for

1. An ultrasound system, comprising: a Doppler signal acquisition unit configured to transmit and receive ultrasound signals to and from a target object to acquire first Doppler signals; anda processing unit configured to compute a plurality of eigenvectors by using the first Doppler signals and form second Doppler signals corresponding to directions of the computed eigenvectors, the processing unit being further configured to compute component values of the second Doppler signals and set eigenvectors for clutter signal filtering among the plurality of eigenvectors by using the computed component values. 2. The ultrasound system of claim 1, wherein the component values include amplitudes of the second Doppler signals. 3. The ultrasound system of claim 1, wherein the processing unit includes: a covariance matrix computing section configured to compute a covariance matrix by using the first Doppler signals;an eigenvector computing section configured to compute the plurality of eigenvectors based on the computed covariance matrix; andan eigenvector setting section configured to compute inner product for the first Doppler signals and the plurality of eigenvectors to compute the component values of the second Doppler signals for respective eigenvector directions and set the eigenvectors for the clutter signal filtering among the plurality of eigenvectors based on component values of the first Doppler signals and the component values of the second Doppler signals. 4. The ultrasound system of claim 3, wherein the eigenvector setting section is configured to: compute correlation between the component values of the first Doppler signals and the component values of the second Doppler signals,detect the component values of the second Doppler signals whose correlation is greater than a predetermined threshold, andset the eigenvectors corresponding to the detected component values of the second Doppler signals as the eigenvectors for the clutter signal filtering. 5. The ultrasound system of claim 4, wherein the processing unit further includes: a filtering section configured to perform the clutter signal filtering upon the plurality of first Doppler signals by using the eigenvectors for the clutter signal filtering; andan image forming section configured to form a color flow image based on the clutter signal filtered Doppler signals. 6. The ultrasound system of claim 1, wherein the component values include phase differences. 7. The ultrasound system of claim 6, wherein the processing unit includes: a covariance matrix computing section configured to compute a covariance matrix by using the first Doppler signals;an eigenvector computing section configured to compute the plurality of eigenvectors based on the computed covariance matrix; andan eigenvector setting section configured to compute inner product for the first Doppler signals and the plurality of eigenvectors to compute the component values of the second Doppler signals for respective eigenvector directions and set the eigenvectors for the clutter signal filtering among the plurality of eigenvectors based on component values of the first Doppler signals and the component values of the second Doppler signals. 8. The ultrasound system of claim 7, wherein the eigenvector setting section is configured to: compute phase differences between nth samples and (n+1)th samples of the second Doppler signals, wherein n is a positive integer greater than 1, anddetect a sign change of the computed phase differences to set the eigenvectors of which the sign change of the phase differences uniformly maintains as the eigenvectors for the clutter signal filtering. 9. The ultrasound system of claim 8, wherein the processing unit further includes: a filtering section configured to perform the clutter signal filtering upon the plurality of first Doppler signals by using the eigenvectors for the clutter signal filtering; andan image forming section configured to form a color flow image based on the clutter signal filtered Doppler signals. 10. A method of setting eigenvectors in an ultrasound system providing a color flow image, comprising: a) transmitting and receiving ultrasound signals to and from a target object to acquire first Doppler signals;b) computing a plurality of eigenvectors by using the first Doppler signals;c) forming second Doppler signals corresponding to directions of the computed eigenvectors and computing component values of the second Doppler signals; andd) setting eigenvectors for clutter signal filtering among the plurality of eigenvectors by using the computed component values. 11. The method of claim 10, wherein the step b) includes: computing covariance matrixes by using the first Doppler signals: andcomputing the plurality of eigenvectors by using the covariance matrixes. 12. The method of claim 10, wherein the component values include amplitudes of the second Doppler signals. 13. The method of claim 12, wherein the step c) includes computing an inner product between the first Doppler signals and the plurality of eigenvectors to compute the component values of the second Doppler signals in respective directions of the eigenvectors. 14. The method of claim 13, wherein the step d) includes: computing correlation between the component values of the first Doppler signals and the component values of the second Doppler signals;detecting the component values of the second Doppler signals whose correlation is greater than a predetermined threshold; andsetting the eigenvectors corresponding to the detected component values of the second Doppler signals as the eigenvectors for the clutter signal filtering. 15. The method of claim 14, further comprising: e) performing the clutter signal filtering upon the plurality of first Doppler signals by using the eigenvectors for the clutter signal filtering;f) forming a color flow image based on the clutter signal filtered Doppler signals; andg) displaying the color flow image. 16. The method of claim 10, wherein the component values include phase differences. 17. The method of claim 16, wherein the step c) includes: performing clutter signal filtering upon the first Doppler signals by using the plurality of eigenvectors according the magnitudes to form the second Doppler signals; andcomputing phase differences between nth samples and (n+1)th samples of the second Doppler signals, wherein n is a positive integer greater than 1. 18. The method of claim 17, wherein the step d) includes detecting a sign change of the computed phase differences to set the eigenvectors of which the sign change of the phase differences uniformly maintains as the eigenvectors for the clutter signal filtering. 19. The method of claim 18, further comprising: e) performing the clutter signal filtering upon the plurality of first Doppler signals by using the eigenvectors for the clutter signal filtering;f) forming a color flow image based on the clutter signal filtered Doppler signals; andg) displaying the color flow image.