Distributed orbit modeling and propagation method for a predicted and real-time assisted GPS system

1. A mobile device, comprising:

a processor for generating a predicted orbital state vector using an initial satellite position and velocity and force model parameters received from a server, the predicted orbital state vector being used to generate satellite navigation data; and

a GNSS receiver in communication with the processor for receiving the satellite navigation data;

wherein the satellite navigation data is valid for a time period.

2. A mobile device as claimed in claim 1 , wherein the GNSS receiver comprises a GPS chip.

3. A mobile device as claimed in claim 1 , wherein the GNSS receiver comprises an Assisted GPS chip.

4. A mobile device as claimed in claim 1 , wherein the initial satellite position and velocity and force model parameters are received from a server prior to generation of the predicted orbital state vector.

5. A mobile device as claimed in claim 1 , wherein the initial satellite position and velocity and force model parameters are received following a request from the mobile device.

6. A mobile device as claimed in claim 5 , wherein the initial satellite position and velocity and force model parameters are current at the time of the request.

7. A mobile device as claimed in claim 1 , wherein the predicted orbital state vector is calculated using a propagation model, the propagation model being selected from multiple propagation models available based on a performance criteria.

8. A mobile device as claimed in claim 1 , wherein the initial satellite position and velocity and force model parameters are received in a data record.

9. A mobile device as claimed in claim 8 , wherein the data record is a change over a previously received data record.

10. A mobile device as claimed in claim 1 , wherein the satellite navigation data is provided in GPS format.

11. A mobile device as claimed in claim 1 , wherein the satellite navigation data is provided in GLONASS format or Galileo format.

12. A method of predicting an orbit of a satellite on a mobile device, the method comprising:

receiving, at a processor of the mobile device, an initial satellite position and velocity and force model parameters;

generating, at the processor, a predicted orbital state vector using an initial satellite position and velocity and force model parameters; and

generating, at the processor, satellite navigation data valid for a time period using the predicated orbital state vector, the processor sending the satellite navigation data to a GNSS receiver of the mobile device.

13. A method as claimed in claim 12 , wherein the initial satellite position and velocity and force model parameters are received from a server prior to the predicted orbital state vector being generated.

14. A method as claimed in claim 12 , wherein the initial satellite position and velocity and force model parameters are received following a request from the mobile device.

15. A method as claimed in claim 14 , wherein the initial satellite position and velocity and force model parameters are current at the time of the request.

16. A method as claimed in claim 12 , wherein the predicted orbital state vector is calculated using a propagation model, the propagation model being selected from multiple propagation models available based on a performance criteria.

17. A method as claimed in claim 12 , wherein the initial satellite position and velocity and force model parameters are received in a data record.

18. A method as claimed in claim 17 , wherein the data record is a change over a previously received data record.

19. A method as claimed in claim 12 , wherein the satellite navigation data is provided in GPS format.

20. A method as claimed in claim 12 , wherein the satellite navigation data is provided in GLONASS format or Galileo format.