Patent · US Expired

Methods and apparatus for automatically determining edge frequency in doppler ultrasound signals

US5582176A · kind A · utility

21Cited by
3References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 15, 1995
Grant dateDec 10, 1996
Priority date
Expiry dateAug 15, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S15/88
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Doppler Ultrasound techniques have been used for many years to measure the flow rate of fluids. One of the challenges in using these techniques is to separate fluid flow signal from background noise. The present invention is directed to methods and apparatus for automatically distinguishing fluid flow signal from noise. It is found that noise in Doppler ultrasound techniques has characteristic of a white Gaussian spectral distribution and the mean noise can be characterized as a constant. The present invention involves measuring ultrasonic signals, generating sets of discrete spectral components from these signals, and statistically determining a maximum likelihood estimation from the spectral components. This estimation is used to calculate the fluid velocity.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.