Range-finding method and apparatus
US8451433B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 6, 2008 |
| Grant date | May 28, 2013 |
| Priority date | — |
| Expiry date | Jun 24, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S17/10
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Range-finding apparatus comprises a source of pulsed radiation of variable repetition rate and a beam-splitter for dividing the pulsed radiation into two portions which are directed respectively to a local retro-reflector and to a retro-reflector co-located with a remote target the range of which is to be determined. The source, beam-splitter and retro-reflectors are arranged in the form of Michelson interferometer together with a detector. The repetition rate of the source is tuned to frequencies f such that round-trip distance to the remote target is mc/f where m is an integer, this condition being detected by observing a heterodyne signal at the detector. Two such frequencies enable range to be determined. The precision with which range is determined may be increased by carrying out interferometry using the two portions. The accuracy of the method does not depend on absolute range (as with triangulation) and is not limited by the speed of timing electronics, as is the case for time-of-flight techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.