Cross-correlation system for time recovery in network-assisted GPS positioning
US6459407B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 2001 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Sep 10, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for measuring time related to satellite navigation data messages used with a satellite-based global positioning systems (GPS). A first record of at least a portion of a satellite data message is received at an entity, which is typically a base station of a wireless communication system. The first record is compared with a second record of the same satellite data message (navigation message) received by a GPS receiver. From the comparison, a time is determined indicating when the satellite date message was transmitted (broadcast). The comparison is made in a way that accounts for the only approximate removal of all modulation of the satellite data message by the acquisition and tracking stages of the GPS receiver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.