TRANSMISSION OF LOCATION INFORMATION BY A TRANSMITTER AS AN AID TO LOCATION SERVICES

• US 20090312034A1
• Filed: 02/24/2009
• Published: 12/17/2009
• Est. Priority Date: 06/13/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Burroughs, Kirk Allan, Patwardhan, Ravindra M.
• Granted Patent: US 8,897,801 B2
• Time in Patent Office: Days
• US Class Current: 455/456.100
• 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 2013/466 by Trilateration, i.e. two antennas or two sensors determine separately the distance to a target, whereby with the knowledge of the baseline length, i.e. the distance between the antennas or sensors, the position data of the target is determined
• CPC Class Codes: G01S 5/0009 Transmission of position information to remote stations involving assistance data G01S5/0236
• CPC Class Codes: G01S 5/0236 Assistance data, e.g. base station almanac

Abstract

Techniques for transmitting location information as an aid to location services are described. In one design, a transmitter may generate a message including coordinate information and uncertainty information for the location of the transmitter. The coordinate information may include latitude and longitude for horizontal location and possibly the height of the transmitter. The uncertainty information may include uncertainty of the horizontal location and possibly uncertainty of the height of the transmitter. The horizontal location uncertainty may be given by a radius of a circle centered at the latitude and longitude of the transmitter. The height uncertainty may be given by a deviation from the height of the transmitter. The transmitter may send the message to at least one receiver in a wireless network. The transmitter may be a base station that may broadcast the message to terminals within its coverage.

Claims

1. A method for wireless communication, comprising:

generating at a transmitter a message comprising coordinate information and uncertainty information for location of the transmitter; and

sending the message from the transmitter to at least one terminal in a wireless network.

2. The method of claim 1, wherein the coordinate information comprises latitude and longitude for horizontal location of the transmitter, and wherein the uncertainty information comprises uncertainty of the horizontal location of the transmitter.

3. The method of claim 2, wherein the uncertainty of the horizontal location of the transmitter is given by a radius of a circle centered at the latitude and longitude of the transmitter.

4. The method of claim 2, wherein the message comprises a latitude field and a longitude field, the latitude field carrying the latitude of the transmitter or a first designated value if the latitude is not known, and the longitude field carrying the longitude of the transmitter or a second designated value if the longitude is not known.

5. The method of claim 2, wherein the coordinate information further comprises height of the transmitter, and wherein the uncertainty information further comprises uncertainty of the height of the transmitter.

6. The method of claim 5, wherein the uncertainty of the height of the transmitter is given by a deviation from the height of the transmitter.

7. The method of claim 5, wherein the message comprises a height field carrying the height of the transmitter or a designated value if the height is not known.

8. The method of claim 1, wherein the transmitter is a base station.

9. The method of claim 8, wherein the message is an overhead message, and wherein the sending the message comprises broadcasting the overhead message from the base station to terminals within coverage of the base station.

10. The method of claim 8, wherein the message is a unicast message, and wherein the sending the message comprises sending the unicast message from the base station to a specific terminal.

11. The method of claim 1, wherein the message is a System Parameters Message or an MC-RR Parameters Message in IS-2000.

12. An apparatus for wireless communication, comprising:

at least one processor configured to generate at a transmitter a message comprising coordinate information and uncertainty information for location of the transmitter, and to send the message from the transmitter to at least one terminal in a wireless network.

13. The apparatus of claim 12, wherein the coordinate information comprises latitude and longitude for horizontal location of the transmitter, and wherein the uncertainty information comprises uncertainty of the horizontal location of the transmitter.

14. The apparatus of claim 13, wherein the coordinate information further comprises height of the transmitter, and wherein the uncertainty information further comprises uncertainty of the height of the transmitter.

15. The apparatus of claim 14, wherein the uncertainty of the horizontal location of the transmitter is given by a radius of a circle centered at the latitude and longitude of the transmitter, and wherein the uncertainty of the height of the transmitter is given by a deviation from the height of the transmitter.

16. An apparatus for wireless communication, comprising:

means for generating at a transmitter a message comprising coordinate information and uncertainty information for location of the transmitter; and

means for sending the message from the transmitter to at least one terminal in a wireless network.

17. The apparatus of claim 16, wherein the coordinate information comprises latitude and longitude for horizontal location of the transmitter, and wherein the uncertainty information comprises uncertainty of the horizontal location of the transmitter.

18. The apparatus of claim 17, wherein the coordinate information further comprises height of the transmitter, and wherein the uncertainty information further comprises uncertainty of the height of the transmitter.

19. The apparatus of claim 18, wherein the uncertainty of the horizontal location of the transmitter is given by a radius of a circle centered at the latitude and longitude of the transmitter, and wherein the uncertainty of the height of the transmitter is given by a deviation from the height of the transmitter.

20. A computer program product, comprising:

a computer-readable medium comprising;

code for causing at least one computer to generate at a transmitter a message comprising coordinate information and uncertainty information for location of the transmitter, and

code for causing the at least one computer to send the message from the transmitter to at least one terminal in a wireless network.

21. A method for wireless communication, comprising:

generating at a base station an overhead message comprising a latitude field carrying latitude of the base station, a longitude field carrying longitude of the base station, and a horizontal location uncertainty field carrying uncertainty of horizontal location of the base station; and

broadcasting the overhead message from the base station to terminals within coverage of the base station.

22. The method of claim 21, wherein the overhead message further comprises a height field carrying height of the base station and a vertical location uncertainty field carrying uncertainty of the height of the base station.

23. The method of claim 22, wherein the overhead message further comprises an indicator field set to a first value to indicate the overhead message including the horizontal location uncertainty field, the height field, and the vertical location uncertainty field or to a second value to indicate the overhead message omitting the horizontal location uncertainty field, the height field, and the vertical location uncertainty field.

24. A method for wireless communication, comprising:

receiving at a terminal a message generated and sent by a transmitter to at least one receiver in a wireless network; and

obtaining coordinate information and uncertainty information for location of the transmitter from the message.

25. The method of claim 24, wherein the coordinate information comprises latitude and longitude for horizontal location of the transmitter, and wherein the uncertainty information comprises uncertainty of the horizontal location of the transmitter.

26. The method of claim 25, wherein the coordinate information further comprises height of the transmitter, and wherein the uncertainty information further comprises uncertainty of the height of the transmitter.

27. The method of claim 26, wherein the uncertainty of the horizontal location of the transmitter is given by a radius of a circle centered at the latitude and longitude of the transmitter, and wherein the uncertainty of the height of the transmitter is given by a deviation from the height of the transmitter.

28. The method of claim 24, further comprising:

using the coordinate information as an initial location estimate for positioning to determine a final location estimate for the terminal.

29. The method of claim 24, further comprising:

determining whether to obtain assistance data for a global navigation satellite system (GNSS) based on the coordinate information and the uncertainty information.

30. The method of claim 24, wherein the transmitter is a base station.

31. The method of claim 30, wherein the message is an overhead message, and wherein the receiving comprises receiving at the terminal the overhead message broadcast by the base station to terminals within coverage of the base station.

32. An apparatus for wireless communication, comprising:

at least one processor configured to receive at a terminal a message generated and sent by a transmitter to at least one receiver in a wireless network, and to obtain coordinate information and uncertainty information for location of the transmitter from the message.

33. The apparatus of claim 32, wherein the coordinate information comprises latitude and longitude for horizontal location of the transmitter, and wherein the uncertainty information comprises uncertainty of the horizontal location of the transmitter.

34. The apparatus of claim 33, wherein the coordinate information further comprises height of the transmitter, and wherein the uncertainty information further comprises uncertainty of the height of the transmitter.

35. The apparatus of claim 34, wherein the uncertainty of the horizontal location of the transmitter is given by a radius of a circle centered at the latitude and longitude of the transmitter, and wherein the uncertainty of the height of the transmitter is given by a deviation from the height of the transmitter.

36. A method for wireless communication, comprising:

receiving at a terminal an overhead message generated and broadcast by a base station to terminals within coverage of the base station; and

obtaining latitude of the base station from a latitude field, longitude of the base station from a longitude field, and uncertainty of horizontal location of the base station from a horizontal location uncertainty field of the overhead message.

37. The method of claim 36, further comprising:

obtaining height of the base station from a height field and uncertainty of the height of the base station from a vertical location uncertainty field of the overhead message.

38. The method of claim 37, further comprising:

determining whether an indicator field of the overhead message is set to a first value or a second value;

reading the horizontal location uncertainty field, the height field, and the vertical location uncertainty field of the overhead message if the indicator field is set to the first value; and

skipping the horizontal location uncertainty field, the height field, and the vertical location uncertainty field if the indicator field is set to the second value.