Relative speed measuring doppler LiDAR
US9778362B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 2015 |
| Grant date | Oct 3, 2017 |
| Priority date | — |
| Expiry date | Nov 25, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/5161
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The general field of the invention is that of Doppler lidars intended to measure the speed of a target. The lidar according to the invention comprises:First means for modulating the optical frequency of the transmission signal, said frequency being the sum of a constant frequency and of a variable frequency of determined amplitude modulated by a periodic temporal function;Second means for computing the spectrum of the measured heterodyne signal and for creating two measurement spectra obtained by shifting the spectrum of the heterodyne signal by a positive and negative frequency value, said realignment frequency equal to the difference between the instantaneous frequency of the transmission signal and the frequency of a signal transmitted at a time shifted by the round-trip travel time between the lidar and the target;Third means for comparing the two measurement spectra, the difference in amplitude between the two spectra at the Doppler frequency determining the direction of the speed of the target.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.