Method and Apparatus for Fast TTFF

• US 20110273329A1
• Filed: 05/05/2011
• Published: 11/10/2011
• Est. Priority Date: 05/06/2010
• Status: Abandoned Application

• Current Assignee: MediaTek, Inc.
• Original Assignee: MediaTek, Inc.
• Inventors: Yau, Wei Guan, Weng, Chin-Tang
• Application Number:
  US13/101,150
• Publication Number:
  US 20110273329A1
• Time in Patent Office: Days
• US Class Current: 342/357.31
• CPC Class Codes: G01S 19/27 creating, predicting or correcting ephemeris or almanac data within the receiver

Abstract

A data model is built using satellite ephemeris data collected over an extended period of time, allowing generation on a server of very precise orbital parameters preferably using a force or numerical method. These orbital parameters are stored in a mobile device. When a First Fix is required by a GNSS system within the mobile device, these stored orbital parameters are used to rapidly generate accurate satellite trajectory data model without requiring access to a broadcasted ephemeris or a network connection. The stored orbital parameters may be modified in part or in whole as required by changing coefficients of the stored parameters.

Claims

1. A position locating method for a Global Navigation Satellite System, the method comprising:

storing a model of a satellite'"'"'s orbital and/or clock data in a mobile device, the model including orbital parameters;

extracting, by the mobile device, satellite trajectory information from the stored orbital parameters;

determining, by the mobile device, the satellite'"'"'s position based on the extracted satellite trajectory information; and

determining position of the mobile device according to the determined satellite'"'"'s position and clock data.

2. The method of claim 1 wherein a force model is used to generate the model.

3. The method of claim 1 wherein the orbital parameters have coefficients.

4. The method of claim 1 wherein the orbital parameters form a polynomial.

5. The method of claim 1 wherein the model comprises error correction terms referring to a reference ephemeris or almanac.

6. A mobile device used in a Global Navigation Satellite System, the device comprising:

a Global Navigation Satellite System module for determining location of the mobile device according to the Global Navigation Satellite System; and

a central processing unit coupled to the Global Navigation Satellite System module and to a memory, the memory comprising;

a model of a satellite'"'"'s orbital and/or clock data including orbital parameters; and

computer code which when executed by the central processing unit extract satellite trajectory information from the orbital parameters stored in the memory, determines the satellite'"'"'s position based on the extracted satellite trajectory information, and determines position of the mobile device according to the determined satellite'"'"'s position.

7. The mobile device of claim 6 wherein a force model is used to generate the model.

8. The mobile device of claim 6 wherein the orbital parameters have coefficients, and the memory further comprises computer code which when executed by the central processing unit updates at least one of the coefficients to reflect a change in the satellite trajectory data.

9. The mobile device of claim 6 wherein the model comprises error correction terms referring to a reference ephemeris or almanac.

10. A non-transitory computer readable medium comprising computer code which when executed by a processor extracts satellite trajectory information from orbital parameters stored in a memory which stores a model of a satellite'"'"'s orbital and/or clock data including orbital parameters;

computer code which when executed by the processor determine the satellite'"'"'s position based on the extracted satellite trajectory information, and computer code which when executed by the processor determines position of a mobile device according to the determined satellite'"'"'s position.