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US6654686B2 · kind B2 · utility
5Cited by
3References
11Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Feb 19, 2002 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | Feb 19, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/258
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A navigation-satellite receiver uses a reference station accessible over a network to store NAV data subframes for pattern matching at a network client. Alternatively, the pattern matching is performed by the server when per-byte communication costs are high. The stored NAV data repeats ephemeris data every thirty seconds, and full almanac data every 12.5 minutes. This permits the client to instantly recognize where in the NAV data sequence its own received signals are, and it need not actually wait to receive the preambles in the TLM words. Several precious seconds are therefore saved in producing a rapid time-to-first-fix.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.