Method and apparatus for processing signal data to form an envelope on line
US5271404A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 25, 1992 |
| Grant date | Dec 21, 1993 |
| Priority date | — |
| Expiry date | Jun 25, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/8979
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for generating a velocity spectrogram is described. The apparatus includes a transducer which is positionable within a vessel. The transducer receives a time-varying Doppler signal which contains information related to fluid velocity values within the vessel. A Fourier transformation device processes the time-varying Doppler signal to generate a sequence of spectra. Each spectrum corresponds to a segment of the time-varying Doppler signal and defines a set of velocities and their corresponding spectral values. A device is used to identify the instantaneous spectral peak velocity within each spectra. The peak velocity corresponds to the highest velocity within a spectra which has a spectral value above a defined threshold value which is related to the background noise level. The sequence of spectral peak velocities is plotted on a visual interface device to form an instantaneous spectral peak velocity waveform.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.