METHOD AND APPARATUS FOR MAINTAINING INTEGRITY OF LONG-TERM ORBITS IN A REMOTE RECEIVER

• US 20070200752A1
• Filed: 12/06/2006
• Published: 08/30/2007
• Est. Priority Date: 06/06/2001
• Status: Abandoned Application

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Global Locate Incorporated (Broadcom, Inc.)
• Inventors: Riben, Matthew, van Diggelen, Frank
• Application Number:
  US11/567,629
• Publication Number:
  US 20070200752A1
• Time in Patent Office: Days
• US Class Current: 342/357.310
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/20 Integrity monitoring, fault detection or fault isolation of space segment
• CPC Class Codes: G01S 19/254 relating to Doppler shift of satellite signals
• 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 19/27 creating, predicting or correcting ephemeris or almanac data within the receiver

Abstract

A method and apparatus for maintaining integrity of long-term-orbit information used by a Global-Navigation-Satellite-System or other positioning receiver is described. The method comprises obtaining a predicted pseudorange from a first set of long-term-orbit information possessed by a positioning receiver; obtaining, at the positioning receiver from at least one satellite, a measured pseudorange; determining validity of the predicted pseudorange as a function of the predicted pseudorange and the measured pseudorange; and excluding from the long-term-orbit information at least a portion thereof when the validity of the predicted pseudorange is deemed invalid. Optionally, the method may comprise updating or otherwise supplementing the long-term-orbit information with other orbit information if the validity of the predicted pseudorange is deemed invalid.

Claims

1. A method, comprising:

obtaining a predicted pseudorange from long-term-orbit information possessed by a first receiver;

obtaining, at a second receiver from at least one satellite, a measured pseudorange;

determining validity of the predicted pseudorange as a function of the predicted pseudorange and the measured pseudorange; and

excluding from the long-term orbit information at least a portion of thereof when the validity of the predicted pseudorange is deemed invalid.

2. The method of claim 1, wherein excluding at least a portion of the long-term orbit information comprises:

discarding long-term orbit information associated with the at least one satellite from which the measured pseudorange is obtained.

3. The method of claim 1, wherein determining validity of the predicted pseudorange comprises:

determining a difference between the predicted pseudorange and the measured pseudorange, and wherein excluding at least a portion of the long-term-orbit information occurs when the difference satisfies a given threshold.

4. The method of claim 1, further comprising:

performing the functions of claim 1 periodically.

5. The method of claim 1, further comprising:

supplementing the long-term-orbit information with other orbit information when the validity of the predicted pseudorange is deemed invalid.

6. The method of claim 5, wherein the other orbit information comprises information selected from the group consisting of broadcast ephemeris, and long-term-orbit information.

7. The method of claim 5, wherein supplementing the long-term-orbit information with orbit information comprises:

discarding the long-term-orbit information in lieu of broadcast ephemeris.

8. The method of claim 5, wherein determining validity of the predicted pseudorange comprises:

determining a difference between the predicted pseudorange and the measured pseudorange, and wherein supplementing the long-term-orbit information with other orbit information occurs when the difference satisfies a given threshold.

9. The method of claim 5, further comprising:

sending from the first receiver a request for the other orbit information when the validity of the predicted pseudorange is deemed invalid; and

receiving at the first receiver, in response to the request, the other orbit information.

10. The method of claim 3, wherein the other orbit information is more current than the long-term-orbit information.

11. The method of claim 5, wherein the other orbit information comprises broadcast ephemeris obtained from the at least one satellite.

12. The method of claim 5, wherein supplementing the long-term-orbit information with the other orbit information comprises:

replacing all of the long-term-orbit information with other long-term-orbit information.

13. The method of claim 1, wherein the first receiver is a remote receiver, and wherein the second receiver is a reference receiver.

14. The method of claim 1, wherein the first and second receivers are the same receiver.

15. The method of claim 14, wherein the same receiver is a remote receiver.

16. A method, comprising:

(a) using long-term-orbit information to determine, at a receiver, a first position of the receiver, wherein the first position comprises at least one first location parameter;

(b) using satellite-navigation data transmitted from at least one satellite to determine, at the receiver, a second position of the receiver, wherein the second position comprises at least one second location parameter;

(c) determining a difference between (i) the at least one first location parameter and (ii) the at least one second location parameter; and

(d) confirming that the long-term-orbit information is valid when the difference satisfies a given threshold.

17. The method of claim 16, wherein the at least one first location parameter comprises a first parameter and a second parameter, wherein the at least one second location parameter comprises a third parameter and a fourth parameter;

wherein the difference comprises a first difference and a second difference;

wherein the first difference comprises a difference between the first and third parameters, wherein the second difference comprises a difference between the second and fourth parameters, and wherein confirming that the long-term-orbit information is valid comprises confirming that the first and second differences satisfy respective thresholds.

18. The method of claim 17, wherein the first parameter is a first altitude and the second parameter is any of first longitude and first latitude, and wherein the third parameter is a second altitude and the second parameter is any of a second longitude and second latitude.

19. The method of claim 16, further comprising:

performing (c) and (d) responsive to a deviation between the first and second positions.

20. The method of claim 16, wherein the at least one first location parameter comprises any of a first longitude, first latitude, first altitude and first common-mode error obtained from the long-term-orbit information, and wherein the at least one second location parameter comprises any of a second longitude, second latitude, second altitude and second common-mode error obtained from the satellite-navigation data transmitted from at least one satellite.

21. The method of claim 20, wherein the at least one first location parameter comprises a plurality of first locations parameters, wherein the at least one second location parameter comprises a plurality of second location parameters, and further comprising:

performing (c) and (d) using each of the pluralities of first and second location parameters.

22. The method of claim 16, further comprising:

excluding from the long-term orbit information at least a portion of thereof when the long-term orbit information is deemed invalid;

obtaining other orbit information from a device remotely located from the receiver; and

supplementing the long-term-orbit information with the other orbit information when the validity of the predicted pseudorange is deemed invalid.

23. The method of claim 22, wherein the other orbit information comprises information selected from the group consisting of broadcast ephemeris, and long-term-orbit information.

24. The method of claim 22, wherein supplementing the long-term-orbit information with the other orbit information comprises:

replacing the long-term-orbit information with the other orbit information.

25. The method of claim 24, further comprising:

sending from the receiver a request for the other orbit information when the difference between satisfies the given threshold; and

receiving at the satellite-signal receiver, in response to the request, the other orbit information.

26. The method of claim 22, wherein supplementing the long-term-orbit information with the other orbit information comprises:

replacing the at least one first location parameter with a third location parameter obtained from the other orbit information when the difference satisfies a given threshold.

27. A receiver comprising:

memory operable to store executable instructions and long-term-orbit information;

a processor operable to obtain from the memory the executable instructions and operable to execute the executable instructions to;

obtain a predicted pseudorange from the long-term-orbit information;

obtain a measured pseudorange from at least one satellite;

determine validity of the predicted pseudorange as a function of the predicted pseudorange and the measured pseudorange; and

exclude from the long-term-orbit information at least a portion thereof when deeming the validity of the predicted pseudorange is deemed invalid.

28. The receiver of claim 27, wherein the executable instructions to exclude at least a portion of the long-term orbit information comprises:

executable instructions to discard long-term orbit information associated with the at least one satellite from which the measured pseudorange is obtained.

29. The receiver of claim 27, further comprising:

executable instructions to supplement the long-term-orbit information with other orbit information when the validity of the predicted pseudorange is deemed invalid.

30. The receiver of claim 29, wherein the other orbit information comprises information selected from the group consisting of broadcast ephemeris, and long-term-orbit information.

31. The receiver of claim 29, wherein executable instructions to supplement the long-term-orbit information comprise:

executable instructions to discard the long-term-orbit information in lieu of broadcast ephemeris.

32. The receiver of claim 27, wherein the executable instructions to determine validity of the predicted pseudorange comprises executable instructions to determine a difference between the predicted pseudorange and the measured pseudorange, and wherein the processor is operable to execute the executable instructions to exclude at least a portion of the long-term-orbit information when the difference satisfies a given threshold.

33. The receiver of claim 27, further comprising:

a transceiver for sending from the receiver a request for the other orbit information when the validity of the predicted pseudorange is deemed invalid; and

for receiving at the receiver, in response to the request, the other orbit information.

34. A system comprising:

a receiver comprising;

a first memory operable to store executable instructions and long-term-orbit information; and

a first processor operable to obtain from the first memory the executable instructions and operable to execute the executable instructions to;

use long-term-orbit information to determine, at the receiver, a first position of the receiver, wherein the first position comprises at least one first location parameter;

use satellite-navigation data transmitted from at least one satellite to determine, at the receiver, a second position of the receiver, wherein the second position comprises at least one second location parameter;

determine a difference between (i) the at least one first location parameter and (ii) the at least one second location parameter; and

confirm that the long-term-orbit information is valid when the difference satisfies a given threshold; and

a server comprising;

a second memory operable to store executable instructions, the long-term-orbit information and other orbit information; and

a second processor operable to obtain from the second memory the executable instructions and operable to execute the executable instructions to;

provide to the receiver the long-term-orbit information; and

provide to the receiver the other orbit information.

35. The system of claim 35, wherein the first processor is further operable to execute the executable instructions to:

exclude from the long-term orbit information at least a portion of thereof when the long-term orbit information is deemed invalid; and

supplement the long-term-orbit information with the other orbit information when the validity of the predicted pseudorange is deemed invalid.

38. The system of claim 35, wherein the first parameter is a first altitude and the second parameter is any of first longitude and first latitude, and wherein the third parameter is a second altitude and the second parameter is any of a second longitude and second latitude.

39. The system of claim 35, wherein the first processor is further operable to execute the executable instructions to determine the difference and to confirm that the long-term-orbit information is valid responsive to a deviation between the first and second positions.

40. The system of claim 35, wherein the first processor is further operable to execute the executable instructions to supplement the at least one first location parameter with a third location parameter obtained from the orbit information when the difference satisfies a given threshold.

36. The system of claim 36, wherein the other orbit information comprises information selected from the group consisting of broadcast ephemeris, and long-term-orbit information.

37. The system of claim 36, wherein the executable instructions to supplement the long-term-orbit information with the other orbit information comprise:

executable instructions to replace the long-term-orbit information with the other orbit information.

41. A system comprising:

a receiver comprising;

a first memory operable to store executable instructions and a first set of long-term-orbit information; and

a first processor operable to obtain from the first memory the executable instructions and operable to execute the executable instructions to;

use the first set of long-term-orbit information to determine, at the receiver, a first position of the receiver, wherein the first position comprises at least one first location parameter;

use satellite-navigation data transmitted from at least one satellite to determine, at the receiver, a second position of the receiver, wherein the second position comprises at least one second location parameter; and

a server comprising;

a second memory operable to store executable instructions, the long-term-orbit information and first and second sets of long-term-other orbit information; and

a second processor operable to obtain from the second memory the executable instructions and operable to execute the executable instructions to;

provide to the receiver the first set of set of long-term-orbit information;

determine a difference between (i) the at least one first location parameter and (ii) the at least one second location parameter;

confirm that the first set of long-term-orbit information is valid when the difference satisfies a given threshold; and

provide to the receiver the second set of long-term-other orbit information.

42. A system comprising:

a first receiver comprising;

a first memory operable to store executable instructions and long-term-orbit information; and

a first processor operable to obtain from the first memory the executable instructions and operable to execute the executable instructions to;

obtain a predicted pseudorange from the long-term-orbit information possessed by the first receiver;

a second satellite-signal receiver comprising;

a second memory operable to store executable instructions; and

a second processor operable to obtain from the second memory the executable instructions and operable to execute the executable instructions to;

obtain, from at least one satellite, a measured pseudorange;

a server comprising;

a third memory operable to store executable instructions, the long-term-orbit information and other orbit information; and

a third processor operable to obtain from the third memory the executable instructions and operable to execute the executable instructions to;

determine validity of the predicted pseudorange as a function of the predicted pseudorange and the measured pseudorange; and

send to the first receiver the other orbit information when the validity of the predicted pseudorange is deemed invalid.

43. The system of claim 42, wherein the executable instructions to determine validity of the predicted pseudorange comprise:

executable instructions to determine a difference between the predicted pseudorange and the measured pseudorange, and wherein the executable instructions to send to the first receiver the second set of long-term-other orbit information occurs when the difference satisfies a given threshold.

44. The system of claim 42, wherein the first receiver is a remote receiver, and wherein the second receiver is a reference receiver.

45. The system of claim 42, wherein the first and second receivers are the same receiver.

46. The system of claim 45, wherein the same receiver is a remote receiver.