Doppler VOR beacons
US3999187A · kind A · utility
3Cited by
2References
3Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 19, 1974 |
| Grant date | Dec 21, 1976 |
| Priority date | — |
| Expiry date | Aug 19, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S1/40
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A Doppler VOR beacon comprising a central antenna modulated with a reference wave and a ring of omnidirectional antennas radiating sidebands of a sub-carrier amplitude modulation of the carrier commutated around the ring of antennas to simulate a rotating source, in which the central antenna in comparison with the ring antennas has a higher gain towards the horizon and over a predetermined angle above the horizon. The central antenna may comprise a vertically stacked array, the elements of which may be Alford loops.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.