System and method for acquiring weak signals in a global positioning satellite system
US7358895B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 2005 |
| Grant date | Apr 15, 2008 |
| Priority date | — |
| Expiry date | Aug 25, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/246
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of acquiring a weak signal includes selecting a first predetection integration time (PIT) interval for processing a digital intermediate frequency (IF) signal, selecting a number of data bit edges within the PIT, computing a plurality of coherent integrations for each data bit edge, selecting a coherent integration, which corresponds to a most likely data combination for each data bit edge, from the plurality of coherent integrations, updating an incoherent integration total for each data bit edge with the coherent integration corresponding to the selected most likely data bit combination for each data bit edge, comparing the incoherent integration total for each data bit edge with a threshold after a predetermined number of steps of the coherent integration computations and incoherent integration total updates, and identifying a code delay from the incoherent integration. The method may also include determining a code delay from an estimated Doppler shift corresponding to the identified code delay. In this method, the coherent integrations are computed using a circular correlation technique that is performed in a manner so the coherent integrations are not independent fro…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.