Direction determining method and apparatus
US3970391A · kind A · utility
11Cited by
5References
49Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 29, 1974 |
| Grant date | Jul 20, 1976 |
| Priority date | — |
| Expiry date | Jul 29, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C15/004
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A direction finding system is disclosed in which a predetermined horizontal plane is established by the projection from one location of an image having illuminated and unilluminated portions corresponding to the predetermined horizontal plane. A receiver at a remote location detects the image at two spaced points amd produces an indication of the center of the transition zone between the illuminated and unilluminated portions of the projected image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.