METHOD AND APPARATUS FOR DECOMPRESSION OF COMPRESSED LONG-TERM-ORBIT DATA

• US 20080189037A1
• Filed: 10/29/2007
• Published: 08/07/2008
• Est. Priority Date: 06/06/2001
• Status: Abandoned Application

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Riben, Matthew, van Diggelen, Frank, de Salas, Javier
• Application Number:
  US11/927,236
• Publication Number:
  US 20080189037A1
• Time in Patent Office: Days
• US Class Current: 701/226
• CPC Class Codes: B64G 1/1014 Navigation satellites
• CPC Class Codes: G01S 19/05 providing aiding data
• 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 processing long-term-orbit data that is valid for an extended period of time into the future (i.e., long-term-orbit data). The long-term-orbit data is processed by reducing redundant information from the data to form compressed long-term-orbit data that is subsequently decompressed or reconstructed for use in a GNSS receiver.

Claims

1. A method for processing long-term-orbit data comprising:

receiving compressed long-term-orbit data; and

performing at least one of decompressing or reconstructing long-term-orbit data from the compressed long-term-orbit data.

2. The method of claim 1, wherein the step of performing at least one of decompressing or reconstructing of the compressed long-term-orbit data comprises extracting a reference long-term-orbit data from the compressed long-term-orbit data.

3. The method of claim 1, wherein the step of performing at least one of decompressing or reconstructing of the compressed long-term-orbit data comprises selecting a current long-term-orbit data.

4. The method of claim 1, wherein the step of performing at least one of decompressing or reconstructing of the compressed long-term-orbit data comprises:

applying a delta long-term-orbit data to a reference long-term-orbit data to determine a current long-term-orbit data.

5. The method of claim 4, wherein the delta long-term-orbit data is determined on a field-by-field basis.

6. The method of claim 4, wherein the current value is at least one of selected, received or computed.

7. The method of claim 4, wherein the step of performing at least one of decompressing or reconstructing of the compressed long-term-orbit data further comprises adding the reference long-term-orbit data to the delta long-term-orbit data.

8. The method of claim 4 further comprising utilizing a dynamic map for at least one of identifying where the data is located within the delta long-term-orbit data or identifying the bit sizes of each parameter within the long-term-orbit data.

9. The method of claim 8, further comprising arranging at least one of the decompressed or the reconstructed long-term-orbit data according to a determined requirement.

10. The method of claim 1, wherein at least one of the compressed, the decompressed or the reconstructed long-term-orbit data comprises:

long-term-orbit data for each satellite of a plurality of satellites forming a set of long-term-orbit data.

11. The method of claim 1, wherein the step of performing at least one of decompressing or reconstructing comprises:

identifying a first long-term-orbit data for at least one satellite as a reference data for said at least one satellite; and

subtracting a second long-term-orbit data from the reference data to form a delta data, for said at least one satellite.

12. The method of claim 11, wherein the first long term satellite orbit data is selected from the set of long term satellite orbit data.

13. The method of claim 11, wherein the first long term satellite orbit data is derived by using information from the set of long term satellite orbit data.

14. The method of claim 11, wherein the first long term satellite orbit data is arbitrary.

15. The method of claim 1, wherein at least one of the compressed, decompressed or reconstructed long-term-orbit data comprises a dynamic range map.

16. The method of claim 1, wherein the compressed long-term-orbit data comprises an indicator of whether a field is at least one of compressed, decompressed or reconstructed.

17. The method of claim 1, wherein the compressed long-term-orbit data comprises scale factors of the delta data.

18. The method of claim 1, wherein the step performing at least one of decompressing or reconstructing compressed long term data comprises:

generating satellite orbit data for a past period of time; and

extending the satellite orbit data into the future.

19. The method of claim 1 further comprising:

transmitting the uncompressed long term bit data to a global-navigation-satellite-system receiver using a wireless communications link.

20. The method of claim 1, further comprising:

transmitting the compressed long-term-data to a global-navigation-satellite-system receives using a wireless communications link.

24. The method of claim 20, further comprising utilizing a dynamic map for at least one of identifying where the data is located within the delta long-term-orbit data or identifying the bit sizes of each parameter within the long-term-orbit data.

21. A method for decompressing long-term-orbit data comprising:

receiving compressed long-term-orbit data;

determining a reference long-term-orbit data; and

determining at least one delta long-term-orbit data representing differences between the reference long-term-orbit data or other long-term-orbit data.

22. The method of claim 21, wherein the reference long-term-orbit data is actual long-term-orbit data selected from a set of long-term-orbit data or arbitrary long-term-orbit data.

23. The method of claim 21, wherein the creating a plurality of delta long-term-orbit data further comprises:

computing a difference between at least one term of one of the other long-term-orbit data or at least one term of the reference long-term-orbit data.

25. The method of claim 21, further comprising generating a bitmask that indicates whether a term of the other long-term-orbit data is at least one of compressed, decompressed or reconstructed.

26. The method of claim 21, further comprising omitting terms from the delta long-term-orbit data when said terms can be reconstructed from the remaining data.

27. The method of claim 21, further comprising arranging the reference long-term-orbit data and the delta long-term-orbit data to form a compressed data set.

28. The method of claim 21, further comprising reconstructing a set of long-term-orbit data using the reference long-term-orbit data and the delta long-term-orbit data.

29. The method of claim 28, wherein the reconstructing step further comprises:

adding a delta term to a reference term.

30. The method of claim 28, wherein the reconstructing step further comprises using a rate term.

31. The method of claim 30, wherein the rate term is multiplied by a time difference.

32. Apparatus for at least one of decompressing or reconstructing long-term-orbit data comprising:

means for receiving compressed long-term-orbit data; and

means for at least one of decompressing or reconstructing long-term-orbit data from the compressed long-term-orbit data.