Space based augmentation system adapted for improving the accuracy and reliability of data provided by a satellite navigation system and associated method

Patent metadata

Field	Value
Publication number	US-9651664-B2
Application number	US-201213646112-A
Country	US
Kind code	B2
Filing date	Oct 5, 2012
Priority date	Oct 7, 2011
Publication date	May 16, 2017
Grant date	May 16, 2017

Abstract

A space-based augmentation system improving the accuracy and reliability of satellite navigation system data includes, each at least: a ground station transmitting data to satellites, a ground station receiving signals transmitted by a satellite and by a satellite equipped with transmitting/receiving means for transmitting data received from the ground transmitting station for a given geographical area; two ground computing centers, redundantly and respectively calculating navigation message streams and transmitting to the ground transmitting station navigation message streams and information representative of Quality of Service provided by the system, from signals transmitted by the ground receiving stations. The computing centers, ground receiving station and ground transmitting station are connected by a communication network. The ground transmitting station selects navigation message streams of a master computing center according to information representative of respective Quality of Service of said computing centers, and said computing centers are synchronized on said master computing center.

First claim

The invention claimed is:

1. A space based augmentation system configured to improve an accuracy and reliability of data provided by a satellite navigation system, comprising:
at least one ground station for transmitting data to satellites,
at least one ground station for receiving signals transmitted by at least one satellite of a navigation system and by at least one satellite equipped with transmitting/receiving means configured to transmit data received from the at least one ground transmitting station intended for a given geographical area,
at least two ground computing centres, redundantly configured to respectively calculate navigation message streams and transmitting to the at least one ground transmitting station the navigation message streams and information representative of a Quality of Service provided by the system, from signals transmitted by the at least one ground receiving station,
said at least two ground computing centres, the at least one ground receiving station and the at least one ground transmitting station being connected by at least one communication network,
the at least one ground transmitting station being configured to select the navigation message streams of one of the at least two ground computing centres and designate that selected ground computing centre as a master computing centre according to the information representative of the respective Quality of Service of said at least two computing centres, and said computing centres being synchronized on said master computing centre.

2. The space based augmentation system according to claim 1 , in which the system is configured to continuously transmit internal variables for synchronizing the master computing centre with the other computing centres.

3. The space based augmentation system according to claim 1 , in which the computing centres are distributed by geographical centres, a geographical centre including at least two of said computing centres, said computing centres of a geographical centre being connected by two-way links of a local area network.

4. The space based augmentation system according to claim 3 , in which said geographical centres are connected by wide area two-way communication networks.

5. A system according to claim 1 , in which the ground transmitting station is configured to modify the selection of the master computing centre, in a new selection cycle, by choosing the geographical centre then the computing centre of said geographical centre, the selected geographical centre being modified in the absence of any navigation message stream from the computing centres of this geographical centre, or in the presence of information representative of a respective Quality of Service below a threshold of the computing centres of this geographical centre.

6. The system according to claim 1 , in which the ground transmitting station is configured to transmit information representative of the master computing centre and its navigation message stream via the intermediary of a transmission network.

7. The system according to claim 6 , in which said transmission network includes at least one transmission satellite.

8. The system according to claim 7 , in which said transmission satellite is geostationary.

9. The space based augmentation system according to claim 1 , in which the system is configured to continuously transmit internal variables for synchronizing calculations of navigation messages from the master computing centre to other computing centres of the at least two computing centres.

10. A method of improving an accuracy and reliability of data provided by a satellite navigation system, comprising:
selecting with at least one ground transmitting station a navigation message stream from one of at least two redundant ground computing centres and designating that selected one of the at least two redundant ground computing centres as a master computing centre, the selecting by the at least one ground transmitting station being based on information representative of a respective Quality of Service of the at least two redundant ground computing centres,
receiving internal variables by other redundant ground computing centres of the at least two redundant ground computing centres from said master computing centre; and
synchronizing the other redundant ground computing centres of the at least two redundant ground computing centres on the internal variables received from said master computing centre.

11. The method according to claim 10 , further comprising continuously transmitting the internal variables from the master computing centre to the other ground computing centres of the at least two redundant ground computing centres.

12. The method according to claim 10 , further comprising continuously transmitting the internal variables for synchronizing calculations of navigation messages from the master computing centre to the other ground computing centres of the at least two redundant ground computing centres.

13. A process of operating a space based augmentation system configured to improve an accuracy and reliability of data provided by a satellite navigation system, comprising:
providing at least one ground station for transmitting data to satellites;
providing at least one ground station for receiving signals transmitted by at least one satellite of a navigation system and by at least one satellite equipped with transmitting/receiving means configured to transmit data received from the at least one ground transmitting station intended for a given geographical area;
providing at least two ground computing centres, redundantly configured to respectively calculate navigation message streams and transmitting to the at least one ground transmitting station the navigation message streams and information representative of a quality of service provided by the system, from signals transmitted by the at least one ground receiving station;
connecting said at least two ground computing centres, the at least one ground receiving station and the at least one ground transmitting station by at least one communication network; and
selecting, with the at least one ground transmitting station, the navigation message streams of one of the at least two ground computing centres and designating that selected ground computing centre as a master computing centre according to the information representative of the respective quality of service of said at least two computing centres, and said computing centres being synchronized on said master computing centre.

Assignees

• Thales Sa

Inventors

• Charlot Bernard
• Bertin De La Hautiere Gonzagues
• Trilles Sebastien

Classifications

• G01S19/08

  providing integrity information, e.g. health of satellites or quality of ephemeris data · CPC title

• G01S19/05

  providing aiding data · CPC title

• G01S5/0081

  Transmission between base stations · CPC title

• G01S5/0009

  Transmission of position information to remote stations (involving assistance data G01S5/0236) · CPC title

• G01S19/074 Primary

  providing integrity data, e.g. WAAS · CPC title