Correction data signal diplexing onto the AM band
US6803879B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 7, 1999 |
| Grant date | Oct 12, 2004 |
| Priority date | — |
| Expiry date | Dec 7, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/07
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for generating signals that can be used for accurately determining position and a method and apparatus for accurately determining position. A radio station modification unit is disclosed that can be incorporated into an existing radio transmission facility. The radio station modification unit generates a correction data signal that can be used by position determining systems for accurately determining position. In one embodiment, the radio station modification unit generates correction data that is encrypted. A position determination system decrypts the correction data upon receiving an activation instruction and uses the correction data to accurately determine position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.