Wide area differential GPS reference system and method
US5621646A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 1996 |
| Grant date | Apr 15, 1997 |
| Priority date | — |
| Expiry date | Jul 22, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/074
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A GPS reference system and corresponding method utilizing a network of reference stations and a master station. Each reference station receives GPS signals from GPS satellites it observes and computes in response a pseudo-range residual for each GPS satellite it observes. The master station is in communication with the reference stations to receive the computed pseudo-range residuals and comprises a pseudo-range residual synchronizer, an ephemeris and clock correction estimator for each GPS satellite observed by the reference stations, and a transmitter. The pseudo-range residual synchronizer is responsive to the received pseudo-range residuals in order to compute clock differences between the reference stations and remove the clock differences from the received pseudo-range residuals so as to synchronize them. Each ephemeris and clock correction estimator computes an ephemeris correction and a clock correction for the corresponding GPS satellite in response to each synchronized pseudo-range residual for the corresponding GPS satellite. The transmitter transmits to users the computed ephemeris and clock corrections for each GPS satellite observed by the reference stations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.