Method and apparatus for locating mobile receivers using a wide area reference network for propagating ephemeris

• US 20020032526A1
• Filed: 11/20/2001
• Published: 03/14/2002
• Est. Priority Date: 07/13/2000
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Frank Van Diggelen
• Inventors: Diggelen, Frank van
• Granted Patent: US 6,704,651 B2
• Time in Patent Office: Days
• US Class Current: 701/213
• CPC Class Codes: G01S 19/06 employing an initial estimate of the location of the receiver as aiding data or in generating 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 19/28 Satellite selection

Abstract

A method and apparatus for distribution and delivery of global positioning system (GPS) satellite telemetry data using a communication link between a central site and a mobile GPS receiver. The central site is coupled to a network of reference satellite receivers that send telemetry data from all satellites to the central site. The mobile GPS receiver uses the delivered telemetry data to aid its acquisition of the GPS satellite signal. The availability of the satellite telemetry data enhances the mobile receiver'"'"'s signal reception sensitivity.

Claims

1. A method for locating position comprising:

receiving satellite telemetry data from all of the satellites in a global positioning system constellation of satellites;

communicating the received satellite telemetry data to a central processing site;

propagating selected satellite telemetry data to a mobile receiver; and

acquiring at least one satellite signal at said mobile receiver using said selected satellite data.

2. The method of claim 1 wherein the selected satellite telemetry data comprises the ephemeris data for each satellite in view of the mobile receiver.

3. The method of claim 2 wherein the selected satellite data comprises a pseudo-range model, derived from the ephemeris data, that represents a relative position of each satellite in view of the mobile receiver.

4. The method of claim 2 wherein the selected satellite telemetry data comprises a Doppler measurement derived from the satellite ephemeris data.

5. The method of claim 1 wherein said acquiring step further comprises:

using the selected satellite telemetry data to narrow a frequency uncertainty and a code uncertainty.

6. The method of claim 1 wherein said receiving step is accomplished using four satellite signal receivers.

7. The method of claim 1 further comprising:

computing a position of said mobile receiver using said selected satellite data.

8. The method of claim 7 wherein said computing step is performed within the mobile receiver.

9. The method of claim 7 wherein said computing step is performed at a location that is remote from said mobile receiver.

10. The method of claim 1 wherein said at least on satellite signal is a signal having a high signal strength and said acquiring step further comprises:

using the at least one acquired satellite signal to aid in receiving other satellite signals having low signal strength.

11. The method of claim 10 wherein said at least one acquired satellite signal is used to generate a clock and a correlator delay offset.

12. The method of claim 10 wherein said at least one acquired satellite signal is used to improve an estimated pseudo-range computation for satellite signals having low signal strength.

14. The method of claim 13 wherein said acquiring step further comprises computing Doppler from said pseudo-range model.

15. The method of claim 13 wherein said satellite telemetry data comprises a satellite clock signal and satellite position information.

16. The method of claim 13 wherein the pseudo-range model is derived from satellite telemetry data comprising ephemeris data for each satellite in view of the mobile receiver.

17. The method of claim 16 wherein the satellite telemetry data comprises a Doppler measurement derived from the satellite ephemeris data.

18. The method of claim 13 wherein said acquiring step further comprises:

using the pseudo-range model to narrow a frequency uncertainty and a code uncertainty.

19. The method of claim 13 wherein said receiving step is accomplished using four satellite signal receivers.

20. The method of claim 13 further comprising:

computing a position of said mobile receiver using said pseudo-range model.

21. The method of claim 20 wherein said computing step is performed within the mobile receiver.

22. The method of claim 20 wherein said computing step is performed at a location that is remote from said mobile receiver.

23. The method of claim 13 wherein said at least on satellite signal is a signal having a high signal strength and said acquiring step further comprises:

using the at least one acquired satellite signal to aid in receiving other satellite signals having low signal strength.

24. The method of claim 13 wherein said at least one acquired satellite signal is used to generate a clock and a correlator delay offset.

25. The method of claim 13 wherein said at least one acquired satellite signal is used to improve an estimated pseudo-range computation for satellite signals having low signal strength.

27. The apparatus of claim 26 wherein said communications network comprises three of more satellite signal receivers.

28. The apparatus of claim 26 further comprising

a wireless network for communicating said satellite data to said mobile receiver.

29. The apparatus of claim 26 wherein said satellite data processor generates a pseudo-range model for each mobile receiver and communicates the pseudo-range model to the mobile receiver.

30. The apparatus of claim 26 wherein said plurality of satellite signal receivers are positioned to receive telemetry data from each and every satellite in a satellite constellation.

31. The apparatus of claim 23 wherein said satellite constellation is a global positioning system (GPS) satellite constellation.

13. A method for locating position comprising:

receiving satellite telemetry data from a plurality of the satellites in a global positioning system constellation of satellites;

communicating the received satellite telemetry data to a central processing site;

deriving a pseudo-range model comprising a pseudo-range, a pseudo-range rate and a pseudo-range acceleration;

propagating the pseudo-range model to a mobile receiver; and

acquiring at least one satellite signal at said mobile receiver using said pseudo-range model.

26. Apparatus for locating a position of a mobile receiver comprising:

a plurality of satellite signal receivers for receiving satellite signals from all satellites in a constellation of global positioning satellites;

a communications network, coupled to each of said satellite signal receivers in said plurality of satellite signal receivers;

a satellite data processor, coupled to said communications network; and

a mobile receiver, coupled to said satellite data processor.

32. Apparatus for providing satellite data to a mobile receiver comprising:

a plurality of tracking stations for receiving telemetry data from satellites; and

a communication network for propagating the telemetry data from all the satellites to a data processor.

33. The apparatus of claim 32 wherein said data processor transmits said data to a mobile receiver.

34. The apparatus of claim 32 wherein said data processor produces a pseudo-range model using said telemetry data.

35. The apparatus of claim 32 wherein the plurality of tracking stations comprise at least three stations.

37. The method of claim 36 wherein said communicating step is performed through a wireless path.

38. The method of claim 36 further comprising generating a pseudo-range model from said satellite ephemeris and communicating the pseudo-range model to the mobile receiver.

36. A method of receiving global positioning system (GPS) satellite signals comprising:

receiving satellite ephemeris at a first location;

communicating the satellite ephemeris to a mobile GLS receiver at a second location; and

processing satellite signals received at the mobile GPS receiver using the ephemeris to reduce code and frequency uncertainty in the mobile GPS receiver to improve acquisition sensitivity of the mobile GPS receiver.