Pulse doppler flow speed meter
US4995397A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 1989 |
| Grant date | Feb 26, 1991 |
| Priority date | — |
| Expiry date | Sep 27, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/584
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a pulse Doppler flow speed meter in which ultrasonic wave pulses are transmitted repetitively at transmission intervals T and thereafter transmitted repetitively at transmission intervals (T+Ts), phases of reflected waves due to reflection of individual transmission pulses are measured sequentially to provide phase signals and the phase signals are subjected to frequency analysis to determine speed distributions, distributions of phase differences between phase signals corresponding to transmission pulses transmitted at the transmission intervals T and distributions of phase differences between phase signals corresponding to transmission pulses transmitted at the transmission intervals (T+Ts) are determined. A value of center of gravity of the former phase difference distributions and a value of center of gravity of the latter phase difference distributions are determined and then a phase difference between the two values of center of gravity is determined. Obtained from the phase difference are values of Doppler shift angle, according to which the former and latter phase difference distributions are shifted so as to be compensated for their aliasing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.