Near-real time DGPS network and server system

• US 6,229,478 B1
• Filed: 11/05/1998
• Issued: 05/08/2001
• Est. Priority Date: 11/05/1998
• Status: Expired due to Term

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Biacs, Zoltan, Rogers, John, Li, Jinye
• Primary Examiner(s): Blum, Theodore M.
• Application Number:
  US09/187,690
• Time in Patent Office: 915 Days
• Field of Search: 342/357.03, 342/357.09, 342/357.1, 701/215
• US Class Current: 342/357.42
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/071 DGPS corrections
• CPC Class Codes: G01S 19/252 Employing an initial estimate of location in generating assistance data
• CPC Class Codes: G01S 19/256 relating to timing, e.g. time of week, code phase, timing offset
• CPC Class Codes: G01S 19/258 relating to the satellite constellation, e.g. almanac, ephemeris data, lists of satellites in view
• CPC Class Codes: G01S 2205/008 using a mobile telephone network

Abstract

A method and system for rapidly initializing a rover unit in a networked system. In one embodiment, the present invention acquires rover unit initialization data at a reference station. In one embodiment, the rover unit initialization data is selected from the group consisting of: ephemeris data, almanac data, satellite health data, ionospheric data, UTC and GPS time and approximate rover position information. In the present embodiment, the present invention then communicatively couples the reference station to a server station having memory for storing the rover unit initialization data. After communicatively coupling the reference station to the server station, the present embodiment transfers the rover unit initialization data from the reference station to the server station. The present embodiment then communicatively couples the rover unit to the server station. Next, the present embodiment supplies the rover unit initialization data from the server station to the rover unit. As a result, in the present embodiment, the rover unit is able to be initialized and obtain a first position fix without requiring the rover unit to acquire the initialization data directly from at least one satellite. In another embodiment, the present invention provides a method and system for providing differentially corrected position information to a rover unit in a networked system. In still another embodiment, the present invention provides a method and system for providing both initialization data and differentially corrected position information to a rover unit in a networked system.

Claims

1. A networked system for providing differentially corrected position information to a rover unit, said networked system comprising:

a server station, said server station having a differential correction engine for differentially correcting position information when requested;

a reference station communicatively coupleable to said server station, said reference station providing differential correction data to said server station such that said server station is able to utilize said differential correction data when differentially correcting position information;

a rover unit communicatively coupleable to said server station, said rover unit having a position generation engine for providing position information of said rover unit, said rover unit further adapted to request said server station to differentially correct said position information of said rover unit and return differentially corrected position information of said rover unit to said rover unit such that said rover unit acquires said differentially corrected position information upon demand without requiring said rover unit to have a differential correction engine integral therewith.

2. The networked system of claim 1 wherein said rover unit is able to acquire said differentially corrected position information upon demand in near-real time.

3. The networked system of claim 1 wherein said rover unit is also able to acquire map information from said server station.

4. The networked system of claim 1 wherein said networked system further provides rapid position information initialization, said networked system further comprising:

said reference station is further adapted to provide rover unit initialization data to said server station;

said server station having memory for storing said rover unit initialization data, said server station adapted for supplying said rover unit initialization data to said rover unit when requested; and

said rover unit further adapted to request said server station to provide said rover unit initialization data to said rover unit such that said rover unit is initialized and obtains a first position fix without requiring said rover unit to acquire said initialization data directly from at least one satellite.

5. The networked system of claim 4 wherein said initialization data is selected from the group consisting of:

ephemeris data, almanac data, satellite health data, ionospheric data, UTC and GPS time information, and approximate rover position information.

6. The networked system of claim 5 wherein said time information is structured such that GPS week numbers do not roll over to zero after week 1023.

7. A networked system for rapidly initializing a rover unit, said networked system comprising:

a server station having memory for storing rover unit initialization data, said server station adapted for supplying said rover unit initialization data when requested;

a reference station communicatively coupleable to said server station, said reference station providing said rover unit initialization data to said server station; and

a rover unit communicatively coupleable to said server station, said rover unit further adapted to request said server station to provide said rover unit initialization data to said rover unit such that said rover unit is initialized and obtains a first position fix without requiring said rover unit to acquire said initialization data directly from at least one satellite.

8. The networked system for rapidly initializing a rover unit of claim 7 wherein said initialization data is selected from the group consisting of:

ephemeris data, almanac data, satellite health data, ionospheric data, utc and GPS time information, and approximate rover position information.

9. The networked system for rapidly initializing a rover unit of claim 8 wherein said time information is structured such that GPS week numbers do not roll over to zero after week 1023.

10. The networked system for rapidly initializing a rover unit of claim 7 wherein said networked system further provides differentially corrected position information, said networked system further comprising:

said server station having a differential correction engine for differentially correcting position information when requested;

said reference station providing differential correction data to said server station such that said server station is able to utilize said differential correction data when differentially correcting position information;

said rover unit having a position generation engine for providing position information of said rover unit, said rover unit further adapted to request said server station to differentially correct said position information of said rover unit and return differentially corrected position information of said rover unit to said rover unit such that said rover unit acquires said differentially corrected position information upon demand without requiring said rover unit to have a differential correction engine integral therewith.

11. The networked system of claim 10 wherein said rover unit is able to acquire said differentially corrected position information upon demand in near-real time.

12. The networked system of claim 10 wherein said rover unit is also able to acquire map information from said server station.

13. A method for rapidly initializing a rover unit, said method comprising the steps of:

a) acquiring rover unit initialization data at a reference station;

b) communicatively coupling said reference station to a server station having memory for storing said rover unit initialization data;

c) transferring said rover unit initialization data from said reference station to said server station;

d) communicatively coupling said rover unit to said server station; and

e) supplying said rover unit initialization data from said server station to said rover unit such that said rover unit is initialized and obtains a first position fix without requiring said rover unit to acquire said initialization data directly from at least one satellite.

14. The method as recited in claim 13 wherein step e) further comprises the step of:

supplying said rover unit initialization data from said server station to said rover unit upon request by said rover unit such that said rover unit is initialized upon demand and obtains said first position fix without requiring said rover unit to acquire said initialization data directly from said at least one satellite.

15. The method as recited in claim 13 wherein step e) further comprises the step of:

supplying initialization data selected from the group consisting of;

ephemeris data, almanac data, satellite health data, ionospheric data, UTC and GPS time information, and approximate rover position information.

16. The method as recited in claim 15 wherein step e) further comprises the step of:

supplying said time information from said server station to said rover unit wherein said time information is structured such that GPS week numbers do not roll over to zero after week 1023.

17. The method as recited in claim 13 further comprising the steps of:

f) acquiring differential correction data at said reference station;

g) communicatively coupling said reference station to said server station having a differential correction engine for differentially correcting received position information when requested;

h) transferring said differential correction data from said reference station to said server station such that said server station is able to utilize said differential correction data when differentially correcting said received position information;

i) communicatively coupling said rover unit having a position generation engine for providing position information of said rover unit to said server station;

j) upon request by said rover unit, transferring said position information of said rover unit to said server station;

k) differentially correcting said position information of said rover unit at said server station such that differentially corrected position information of said rover unit is calculated by said server station; and

l) transferring said differentially corrected position information of said rover unit from said server station to said rover unit such that said rover unit acquires said differentially corrected position information upon demand without requiring said rover unit to have a differential correction engine integral therewith.

18. The method as recited in claim 17 wherein step l) comprises transferring said differentially corrected position information to said rover nit in near-real time such that said rover unit receives said differentially corrected position information of said rover unit upon demand and in near-real time.

19. The method as recited in claim 17 wherein step l) comprises transferring map information to said rover unit.

20. A method for providing differentially corrected position information to a rover unit in a networked system, said method comprising the steps of:

a) acquiring differential correction data at a reference station;

b) communicatively coupling said reference station to a server station having a differential correction engine for differentially correcting received position information when requested;

c) transferring said differential correction data from said reference station to said server station such that said server station is able to utilize said differential correction data when differentially correcting said received position information;

d) communicatively coupling a rover unit having a position generation engine for providing position information of said rover unit to said server station;

e) upon request by said rover unit, transferring said position information of said rover unit to said server station;

f) differentially correcting said position information of said rover unit at said server station such that differentially corrected position information of said rover unit is calculated by said server station; and

g) transferring said differentially corrected position information of said rover unit from said server station to said rover unit such that said rover unit acquires said differentially corrected position information upon demand without requiring said rover unit to have a differential correction engine integral therewith.

21. The method for providing differentially corrected position information to a rover unit in a networked system as recited in claim 20 wherein step g) comprises transferring said differentially corrected position information to said rover unit in near-real time such that said rover unit receives said differentially corrected position information of said rover unit upon demand and in near-real time.

22. The method for providing differentially corrected position information to a rover unit in a networked system as recited in claim 20 wherein step g) comprises transferring map information to said rover unit.

23. The method for providing differentially corrected position information to a rover unit in a networked system as recited in claim 20 said method comprising the steps of:

h) acquiring rover unit initialization data at said reference station;

i) communicatively coupling said reference station to said server station having memory for storing said rover unit initialization data;

j) transferring said rover unit initialization data from said reference station to said server station;

k) communicatively coupling said rover unit to said server station; and

l) supplying said rover unit initialization data from said server station to said rover unit such that said rover unit is initialized and obtains a first position fix without requiring said rover unit to acquire said initialization data directly from at least one satellite.

24. The method as recited in claim 23 wherein step l) further comprises the step of:

supplying said rover unit initialization data from said server station to said rover unit upon request by said rover unit such that said rover unit is initialized upon demand and obtains said first position fix without requiring said rover unit to acquire said initialization data directly from said at least one satellite.

25. The method as recited in claim 23 wherein step l) further comprises the step of:

supplying initialization data selected from the group consisting of;

ephemeris data, almanac data, satellite health data, ionospheric data, UTC and GPS time information, and approximate rover position information.

26. A rover unit adapted for use in a networked system, said rover unit comprising:

a position generation engine for providing position information of said rover unit;

a communication link portion coupled to said position generation engine, said communication link portion adapted to communicatively couple said rover unit to a server station, said rover unit further adapted to request said server station to differentially correct said position information of said rover unit and return differentially corrected position information of said rover unit to said rover unit such that said rover unit acquires said differentially corrected position information upon demand without requiring said rover unit to have a differential correction engine integral therewith.

27. The rover unit of claim 26 wherein said rover unit is able to acquire said differentially corrected position information upon demand in near-real time.

28. The rover unit of claim 26 wherein said rover unit is able to acquire map information from said server station.

29. The rover unit of claim 26 wherein said rover unit is further adapted to receive rover unit initialization data from said server station such that said rover unit is initialized and obtains a first position fix without requiring said rover unit to acquire said initialization data directly from at least one satellite.

30. The rover unit of claim 26 wherein said rover unit is adapted to receive said rover unit initialization data selected from the group consisting of:

ephemeris data, almanac data, satellite health data, ionospheric data, utc and GPS time information, and approximate rover position information.