METHOD AND DEVICE FOR PREDICTING GNSS SATELLITE TRAJECTORY EXTENSION DATA USED IN MOBILE APPARATUS

• US 20090135061A1
• Filed: 04/15/2008
• Published: 05/28/2009
• Est. Priority Date: 11/26/2007
• Status: Active Grant

• Current Assignee: MediaTek, Inc.
• Original Assignee: MediaTek, Inc.
• Inventors: Fu, Ching-Lung, Weng, Chin-tang, Tsai, Yeou-jyh
• Granted Patent: US 7,786,929 B2
• Time in Patent Office: Days
• US Class Current: 342/357.590
• CPC Class Codes: G01S 19/27 creating, predicting or correcting ephemeris or almanac data within the receiver

Abstract

A method and device for predicting satellite trajectory extension data used in a mobile apparatus. The device in accordance with the present invention comprises an I/O interface and a microprocessor. The input/output (I/O) interface is used for obtaining at least one satellite navigation message for a satellite. The microprocessor is used for determining a propagating condition according to the satellite navigation message, estimating a plurality of parameters of a satellite trajectory prediction model according to the propagating condition, and propagating a set of satellite trajectory extension data by using the satellite trajectory prediction model.

Claims

1. A method for predicting GNSS satellite trajectory extension data used in a mobile apparatus, said method comprising steps of:

obtaining at least one satellite navigation message for a satellite;

determining a propagating condition according to the obtained satellite navigation message;

estimating a plurality of parameters of a satellite trajectory prediction model according to the propagating condition; and

propagating a set of satellite trajectory extension data by using the estimated satellite trajectory prediction model.

2. The method of claim 1, further comprising adjusting the propagating condition of the satellite trajectory prediction model to find an optimized state of the satellite trajectory prediction model.

3. The method of claim 2, wherein the parameters are adjusted with consideration of at least one of either satellite geometric information or coordinate transformation information.

4. The method of claim 1, wherein the satellite trajectory prediction model is a compact force model parameterized by perturbation force components, and the parameters relate to the perturbation force components.

5. The method of claim 4, wherein the satellite trajectory extension data set is divided into a plurality of trajectory segments and is propagated by integrating the trajectory segments one by one.

6. The method of claim 1, wherein the satellite trajectory prediction model is an adjusted orbit model parameterized by orbital parameters.

7. The method of claim 6, wherein the orbital parameters include Keplerian orbital elements.

8. The method of claim 7, wherein the orbital parameters further include a plurality of dynamic parameters for describing addition perturbed accelerations acting on the satellite.

9. The method of claim 1, wherein the satellite navigation message comprises information selected from a group consisting of broadcasting ephemeris, almanac, satellite position state vectors and satellite velocity state vectors.

10. The method of claim 1, wherein the satellite navigation message is obtained from an external source other than the mobile apparatus.

11. A device for predicting GNSS satellite trajectory extension data used in a mobile apparatus, said device comprising:

an interface for obtaining at least one satellite navigation message for a satellite; and

a microprocessor for determining a propagating condition according to the satellite navigation message, estimating a plurality of parameters of a satellite trajectory prediction model according to the propagating condition, and propagating a set of satellite trajectory extension data by using the satellite trajectory prediction model.

12. The device of claim 11, wherein the microprocessor further adjusts the propagating condition of the satellite trajectory prediction model to find an optimized state of the satellite trajectory prediction model.

13. The device of claim 12, wherein the parameters are adjusted with consideration of at least one of either satellite geometric information or coordinate transformation information.

14. The device of claim 11, wherein the satellite trajectory prediction model is a compact force model parameterized by perturbation force components, and the parameters relate to the perturbation force components.

15. The device of claim 14, wherein the satellite trajectory extension data set is divided into a plurality of trajectory segments and is propagated by integrating the trajectory segments one by one.

16. The device of claim 11, wherein the satellite trajectory prediction model is an adjusted orbit model parameterized by orbital parameters.

17. The device of claim 16, wherein the orbital parameters include Keplerian orbital elements.

18. The device of claim 17, wherein the orbital parameters further include a plurality of dynamic parameters for describing additional perturbed accelerations acting on the satellite.

19. The device of claim 11, wherein the satellite navigation message comprises information selected from a group consisting of broadcasting ephemeris, almanac, satellite position state vectors and satellite velocity state vectors.

20. The device of claim 11, wherein the satellite navigation message is obtained from an external source other than the mobile apparatus.