Method of Keeping a GPS Receiver in a State That Enables Rapid Signal Acquisition

• US 20110254733A1
• Filed: 06/30/2011
• Published: 10/20/2011
• Est. Priority Date: 11/13/2008
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Abraham, Charlie, van Diggelen, Frank
• Granted Patent: US 8,823,587 B2
• Time in Patent Office: Days
• US Class Current: 342/357.66
• CPC Class Codes: G01S 19/27 creating, predicting or correcting ephemeris or almanac data within the receiver
• CPC Class Codes: G01S 19/34 Power consumption

Abstract

Aspects of a method and system for keeping a device for satellite navigation in a state that enables rapid signal acquisition are provided. The device may acquire broadcast ephemeris from one or more satellite signals during a data refresh operation. The satellite signals may comprise a GPS signal, a GLONASS signal, a GALILEO signal, or a combination thereof. The device may compute extended or future ephemeris from the acquired broadcast ephemeris during the data refresh operation. In a positioning operation that is subsequent to the data refresh operation, the device may determine satellite navigation information from the computed extended ephemeris. In some instances, a time associated with a schedule of the data refresh operation may be adjusted based on the computed extended ephemeris. The extended ephemeris may be computed by integrating current and/or historic broadcast ephemeris into an orbit model.

Claims

1. A method, comprising:

in a device that is operable for satellite navigation;

acquiring broadcast ephemeris from one or more satellite signals during a data refresh operation;

computing extended ephemeris from the acquired broadcast ephemeris during the data refresh operation; and

determining satellite navigation information from the computed extended ephemeris during a positioning operation that is different from the data refresh operation and subsequent to the data refresh operation.

2. The method of claim 1, comprising dynamically adjusting a time associated with a schedule of the data refresh operation based on the computed extended ephemeris.

3. The method of claim 1, comprising transitioning from the data refresh operation to a low-power mode of the device.

4. The method of claim 1, comprising:

storing the computed extended ephemeris in a memory in the device during the data refresh operation; and

reading the stored computed extended ephemeris from the memory during the positioning operation.

5. The method of claim 1, wherein the one or more satellite signals comprise a GPS signal, a GLONASS signal, a GALILEO signal, or a combination thereof.

6. The method of claim 1, comprising transitioning from the positioning operation to a low-power mode of the device.

7. The method of claim 1, comprising computing the extended ephemeris by integrating one or both of current broadcast ephemeris and historic broadcast ephemeris into an orbit model.

8. The method of claim 7, wherein the orbit model comprises a solar radiation pressure model.

9. The method of claim 1, comprising:

determining a curve fitting polynomial of the computed extended ephemeris during the data refresh operation; and

storing the determined curve fitting polynomial in a memory in the device during the data refresh operation.

10. The method of claim 1, comprising computing extended ephemeris for more than one GNSS satellite during the data refresh operation.

12. The system of claim 1, wherein the one or more processors and/or circuits are operable to dynamically adjust a time associated with a schedule of the data refresh operation based on the computed extended ephemeris.

13. The system of claim 1, wherein the one or more processors and/or circuits are operable to transition from the data refresh operation to a low-power mode of the device.

11. A system, comprising:

one or more processors and/or circuits for use in a device that is operable for satellite navigation, the one or more processors and/or circuits being operable to;

acquire broadcast ephemeris from one or more satellite signals during a data refresh operation;

compute extended ephemeris from the acquired broadcast ephemeris during the data refresh operation; and

determine satellite navigation information from the computed extended ephemeris during a positioning operation that is different from the data refresh operation and subsequent to the data refresh operation.

14. The system of claim 11, wherein the one or more processors and/or circuits are operable to:

store the computed extended ephemeris in a memory in the device during the data refresh operation; and

reading the stored computed extended ephemeris from the memory during the positioning operation.

15. The system of claim 11, wherein the one or more satellite signals comprise a GPS signal, a GLONASS signal, a GALILEO signal, or a combination thereof.

16. The system of claim 11, wherein the one or more processors and/or circuits are operable to transition from the positioning operation to the low-power mode of the device.

17. The system of claim 11, wherein the one or more processors and/or circuits are operable to compute the extended ephemeris by integrating one or both of current broadcast ephemeris and historic broadcast ephemeris into an orbit model.

18. The system of claim 17, wherein the orbit model comprises a solar radiation pressure model.

19. The system of claim 11, wherein the one or more processors and/or circuits are operable to:

determine a curve fitting polynomial of the computed extended ephemeris during the data refresh operation; and

storing the determined curve fitting polynomial in a memory in the device during the data refresh operation.

20. The system of claim 11, wherein the one or more processors and/or circuits are operable to compute extended ephemeris for more than one GNSS satellite during the data refresh operation.