Doppler pseudorandom noise velocimeters
US4320765A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 1980 |
| Grant date | Mar 23, 1982 |
| Priority date | — |
| Expiry date | Jan 16, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S15/586
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This invention is directed to improved pseudorandom noise velocimeters and methods therefor, using the Doppler effect, to enable the external measurement of the speed of a moving target within a fixed conveying medium. In accordance with a preferred embodiment of the present invention a continuous pseudorandom ultrasonic noise signal formed by a repetitive code C having n different elementary segments S is radiated. Correlation between a received echo and the delayed radiated signal is accomplished by proceeding successively for each elementary segment, using a different measuring band, for a period corresponding to the period of each segment. The correlation values thus obtained are then stored and thereafter a Doppler low frequency curve is reconstituted by regrouping the correlation values corresponding to the different elementary segments of the repetitive code.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.