RELATIVE POSITIONING APPLICATIONS IN WIRELESS DEVICES

• US 20140022050A1
• Filed: 08/24/2012
• Published: 01/23/2014
• Est. Priority Date: 07/20/2012
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: DUA, Praveen, GARIN, Lionel Jacques
• Granted Patent: US 8,933,776 B2
• Time in Patent Office: Days
• US Class Current: 340/5.2
• CPC Class Codes: G01S 13/765 with exchange of information between interrogator and responder
• CPC Class Codes: G01S 13/876 Combination of several spaced transponders or reflectors of known location for determining the position of a receiver G01S13/874 takes precedence
• CPC Class Codes: G01S 13/91 for traffic control G01S13/93 takes precedence
• CPC Class Codes: H04W 4/021 Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences
• CPC Class Codes: H04W 64/003 locating network equipment

Abstract

Techniques for determining whether a mobile device crosses a boundary defined by a first wireless access point (WAP) and a second fixed-location WAP are provided. A method according to these techniques includes receiving, at a mobile device, information defining a boundary defined by first and second fixed-location WAPs, the boundary being defined at least in part based on a ratio of a round trip time (RTT) between the mobile device and the first fixed-location WAP to a ratio of a RTT between the mobile device and the second fixed-location WAP, determining the ratio of the RTT between the mobile device and the first fixed-location WAP to a ratio of the RTT between the mobile device and the second fixed-location WAP, determining whether the mobile device has crossed the boundary, and triggering an event in response to the mobile device crossing the boundary.

Claims

1. A method for determining whether a mobile device crosses a boundary defined by a first wireless access point and a second wireless access point, the method comprising:

receiving, at the mobile device, information defining the boundary defined by the first wireless access point and the second wireless access point, the boundary being defined at least in part based on a ratio of a round trip time (RTT) between the mobile device and the first wireless access point to an RTT between the mobile device and the second wireless access point;

determining the ratio of the RTT between the mobile device and the first wireless access point to the RTT between the mobile device and the second wireless access point;

determining whether the mobile device has crossed the boundary; and

triggering an event responsive to the mobile device crossing the boundary.

2. The method of claim 1, further comprising:

determining the RTT between the mobile device and the first wireless access point by measuring a first amount of time from transmission of a first message from the mobile device to receipt of a first acknowledgement of the first message at the mobile device; and

determining the RTT between the mobile device and the second wireless access point by measuring a second amount of time from transmission of a second message from the mobile device to receipt of a second acknowledgement of the second message at the mobile device.

3. The method of claim 1, further comprising:

determining a set of possible positions of the mobile device relative to the first wireless access point and the second wireless access point.

4. The method of claim 1 wherein the boundary comprises a line separating the first wireless access point and the second wireless access point.

5. The method of claim 1 further comprising:

repeatedly determining RTT values between the mobile device and the first wireless access point and RTT values between the mobile device and the second wireless access point; and

determining a direction of travel of the mobile device based at least in part on the RTT values;

wherein determining whether the mobile device crosses the boundary comprises determining whether the mobile device crosses the boundary in a first direction or in a second direction based on the direction of travel of the mobile device; and

wherein triggering the event comprises triggering the event responsive to the mobile device crossing the boundary in the first direction.

6. The method of claim 1 wherein the mobile device is mounted on a vehicle and the first wireless access point and the second wireless access point are mounted proximate and collinear to a roadway on which the vehicle is traveling.

7. The method of claim 1 wherein the mobile device is associated with a vehicle and the boundary is associated with an entrance to a paid access area.

8. The method of claim 7 wherein the paid access area comprises a toll road.

9. The method of claim 7 wherein the paid access area comprises a pay parking lot.

10. The method of claim 9 further comprising:

triggering storage of a time stamp responsive to the mobile device crossing the boundary in a first direction to enter the pay parking lot; and

triggering calculation of parking fees based on an elapsed time in the pay parking lot responsive to the mobile device crossing the boundary in a second direction.

11. An apparatus for determining whether a mobile device crosses a boundary defined by a first wireless access point and a second wireless access point, the apparatus comprising:

means for receiving, at the mobile device, information defining the boundary defined by the first wireless access point and the second wireless access point, the boundary being defined at least in part based on a ratio of a round trip time (RTT) between the mobile device and the first wireless access point to a RTT between the mobile device and the second wireless access point;

means for determining the ratio of the RTT between the mobile device and the first wireless access point to the RTT between the mobile device and the second wireless access point;

means for determining whether the mobile device has crossed the boundary; and

means for triggering an event responsive to the mobile device crossing the boundary.

12. The apparatus of claim 11, further comprising:

means for determining the RTT between the mobile device and the first wireless access point by measuring a first amount of time from transmission of a first message from the mobile device to receipt of a first acknowledgement of the first message at the mobile device; and

means for determining the RTT between the mobile device and the second wireless access point by measuring a second amount of time from transmission of a second message from the mobile device to receipt of a second acknowledgement of the second message at the mobile device.

13. The apparatus of claim 11, further comprising:

means for determining a set of possible positions of the mobile device relative to the first wireless access point and the second wireless access point.

14. The apparatus of claim 11 wherein the boundary comprises a line separating the first wireless access point and the second wireless access point.

15. The apparatus of claim 11 further comprising:

means for repeatedly determining RTT values between the mobile device and the first wireless access point and RTT values between the mobile device and the second wireless access point; and

means for determining a direction of travel of the mobile device based at least in part on the RTT values;

wherein the means for determining whether the mobile device crosses the boundary comprises means for determining whether the mobile device crosses the boundary in a first direction or in a second direction based on the direction of travel of the mobile device; and

wherein the means for triggering the event is responsive to the mobile device crossing the boundary in the first direction.

16. The apparatus of claim 11 wherein the mobile device is mounted on a vehicle and the first wireless access point and the second wireless access point are mounted proximate and collinear to a roadway on which the vehicle is traveling.

17. The apparatus of claim 11 wherein the mobile device is associated with a vehicle and the boundary is associated with an entrance to a paid access area.

18. The apparatus of claim 17 wherein the paid access area comprises a toll road.

19. The apparatus of claim 17 wherein the paid access area comprises a pay parking lot.

20. The apparatus of claim 19 further comprising:

means for triggering storage of a time stamp responsive to the mobile device crossing the boundary in a first direction to enter the pay parking lot; and

means for triggering calculation of parking fees based on an elapsed time in the pay parking lot responsive to the mobile device crossing the boundary in a second direction.

21. A computer-readable storage medium, having stored thereon computer-readable instructions for determining whether a mobile device crosses a boundary defined by a first wireless access point and a second wireless access point, comprising instructions configured to cause at least one processor to:

receive, at the mobile device, information defining the boundary defined by the first wireless access point and the second wireless access point, the boundary being defined at least in part based on a ratio of a round trip time (RTT) between the mobile device and the first wireless access point to an RTT between the mobile device and the second wireless access point;

determine the ratio of the RTT between the mobile device and the first wireless access point to the RTT between the mobile device and the second wireless access point;

determine whether the mobile device has crossed the boundary; and

trigger an event responsive to the mobile device crossing the boundary.

22. The computer-readable storage medium of claim 21, further comprising instructions configured to cause the at least one processor to:

determine the RTT between the mobile device and the first wireless access point by measuring a first amount of time from transmission of a first message from the mobile device to receipt of a first acknowledgement of the first message at the mobile device; and

determine the RTT between the mobile device and the second wireless access point by measuring a second amount of time from transmission of a second message from the mobile device to receipt of a second acknowledgement of the second message at the mobile device.

23. The computer-readable storage medium of claim 21, further comprising instructions configured to cause the at least one processor to:

determine a set of possible positions of the mobile device relative to the first wireless access point and the second wireless access point.

24. The computer-readable storage medium of claim 21 wherein the boundary comprises a line separating the first wireless access point and the second wireless access point.

25. The computer-readable storage medium of claim 21 further comprising instructions to cause the at least one processor to:

repeatedly determine RTT values between the mobile device and the first wireless access point and RTT values between the mobile device and the second wireless access point; and

determine a direction of travel of the mobile device based at least in part on the RTT values;

wherein the instructions to cause the at least one processor to determine whether the mobile device crosses the boundary comprise instructions to cause the at least one processor to determine whether the mobile device crosses the boundary in a first direction or in a second direction based on the direction of travel of the mobile device; and

wherein the instructions to cause the at least on processor to trigger the event comprise instructions to cause the at least one processor to trigger the event responsive to the mobile device crossing the boundary in the first direction.

26. The computer-readable storage medium of claim 21 wherein the mobile device is mounted on a vehicle and the first wireless access point and the second wireless access point are mounted proximate and collinear to a roadway on which the vehicle is traveling.

27. The computer-readable storage medium of claim 21 wherein the mobile device is associated with a vehicle and the boundary is associated with an entrance to a paid access area.

28. The computer-readable storage medium of claim 27 wherein the paid access area comprises a toll road.

29. The computer-readable storage medium of claim 27 wherein the paid access area comprises a pay parking lot.

30. The computer-readable storage medium of claim 29 further comprising instructions configured to cause the at least one processor to:

trigger storage of a time stamp responsive to the mobile device crossing the boundary in a first direction to enter the pay parking lot; and

trigger calculation of parking fees based on an elapsed time in the pay parking lot responsive to the mobile device crossing the boundary in a second direction.

31. An apparatus for determining whether a mobile device crosses a boundary defined by a first wireless access point and a second wireless access point comprising:

a wireless transceiver configured to transmit signals to and to receive signals from the first wireless access point and the second wireless access point;

a non-transitory computer-readable memory;

a plurality of modules comprising processor executable code stored in the non-transitory computer-readable memory;

a processor connected to the non-transitory computer-readable memory and configured to access the plurality of modules stored in the non-transitory computer-readable memory; and

a relative positioning module configured to

receive, at the mobile device, information defining the boundary defined by the first wireless access point and the second wireless access point, the boundary being defined at least in part based on a ratio of a round trip time (RTT) between the mobile device and the first wireless access point to an RTT between the mobile device and the second wireless access point;

determine the ratio of the RTT between the mobile device and the first wireless access point to the RTT between the mobile device and the second wireless access point;

determine whether the mobile device has crossed the boundary; and

trigger an event responsive to the mobile device crossing the boundary.

32. The apparatus of claim 31 wherein the relative positioning module is further configured to:

determine the RTT between the mobile device and the first wireless access point by measuring a first amount of time from transmission of a first message from the mobile device to receipt of a first acknowledgement of the first message at the mobile device; and

determine the RTT between the mobile device and the second wireless access point by measuring a second amount of time from transmission of a second message from the mobile device to receipt of a second acknowledgement of the second message at the mobile device.

33. The apparatus of claim 31 wherein the relative positioning module is further configured to:

determine a position of the mobile device relative to the first wireless access point and the second wireless access point.

34. The apparatus of claim 31 wherein the boundary comprises a line separating the first wireless access point and the second wireless access point.

35. The apparatus of claim 31 wherein the relative positioning module being configured to trigger the event responsive to the mobile device crossing the boundary is further configured to:

repeatedly determine RTT values between the mobile device and the first wireless access point and RTT values between the mobile device and the second wireless access point; and

determine a direction of travel of the mobile device based at least in part on the RTT values;

wherein the relative positioning module being configured to determine whether the mobile device crosses the boundary is further configured to determine whether the mobile device crosses the boundary in a first direction or in a second direction based on the direction of travel of the mobile device; and

wherein the relative positioning module being configured to trigger the event is further configured to trigger the event responsive to the mobile device crossing the boundary in the first direction.

36. The apparatus of claim 31 wherein the mobile device is mounted on a vehicle and the first wireless access point and the second wireless access point are mounted proximate and collinear to a roadway on which the vehicle is traveling.

37. The apparatus of claim 31 wherein the mobile device is associated with a vehicle and the boundary is associated with an entrance to a paid access area.

38. The apparatus of claim 37 wherein the paid access area comprises a toll road.

39. The apparatus of claim 37 wherein the paid access area comprises a pay parking lot.

40. The apparatus of claim 39 wherein the relative positioning module is further configured to:

trigger storage of a time stamp responsive to the mobile device crossing the boundary in a first direction to enter the pay parking lot; and

trigger calculation of parking fees based on an elapsed time in the pay parking lot responsive to the mobile device crossing the boundary in a second direction.

41-72. -72. (canceled)