IP Library Granted Patent US 8,380,220
Granted Patent B2
US 8,380,220 · App. 13/302,754 · Granted Feb 19, 2013

System and method for generating a location estimate using a method of intersections

Inventors: Martin Alles (Vienna, VA); John Carlson (Dulles, VA); George Maher (Herndon, VA); Selcuk Mazlum (Leesburg, VA)
Assignee: Andrew LLC
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Quick Facts
Patent No.
US 8,380,220
App. No.
13/302,754
Granted
Feb 19, 2013
Kind
B2
Abstract

The location of a wireless mobile device may be estimated using, at least in part, one or more pre-existing Network Measurement Reports (“NMRs”) which include calibration data for a number of locations within a geographic region. The calibration data for these locations is gathered and analyzed so that particular grid points within the geographic region can be determined and associated with a particular set or sets of calibration data from, for example, one or more NMRs. Regions may be defined as a function of any number of parameters and respective predetermined ranges thereof in the NMRs. An intersection of these defined regions may be determined and the location of a mobile device may be estimated as a function of the intersection.

Claims (136)

1. A method of estimating the location of a mobile device in a geographic region comprising the steps of:

(a) providing calibration data for each of one or more calibration points in a geographic region, said calibration data including at least one characterizing parameter

(b) receiving a network measurement report from a mobile device at an unknown location, said network measurement report also including at least one characterizing parameter;

(c) defining a first region within said calibration data as a function of a first characterizing parameter of said network measurement report and a predetermined range of said first parameter;

(d) defining a second region within said calibration data as a function of another characterizing parameter of said network measurement report and a predetermined range of said another parameter;

(e) repeating steps (c)-(d) for each characterizing parameter in said network measurement report;

(f) determining an intersection of each defined region; and

(g) estimating the location of a mobile device in said geographic region as a function of said intersection,

wherein the step of estimating the location of a mobile device comprises:

(i) comparing an ordered list of cells neighboring a cell serving said mobile device in said network measurement report to an ordered list of neighboring cells in each calibration point of said intersection, said ordering being a function of any parameter of said network measurement report; and

(ii) generating an estimated location of said mobile device wherein said estimated location is selected from the group consisting of: a centroid of a cluster of matching calibration points in said intersection; a highest joint probability matching calibration point in said intersection; a weighted sum of the locations of a set of matching calibration points in said intersection; a weighted sum of clustered locations of a set of matching calibration points in said intersection; and as a function of estimated locations determined from a subset of said network measurement report.

2. The method of claim 1 wherein one of said calibration points is located on a predetermined fixed uniform grid defined over said geographic region.

3. The method of claim 1 wherein one of said calibration points is randomly located within said geographic region.

4. The method of claim 1 wherein said calibration data comprises information from at least one network measurement report having a known location.

5. The method of claim 1 wherein said calibration data for one of said calibration points is obtained from one or more mobile devices located in close proximity to said one calibration point.

6. The method of claim 1 wherein said calibration data for one of said calibration points is obtained from a signal transmitted from a mobile device in close proximity to said one calibration point and received at a receiver in or in proximity to said geographic region.

7. The method of claim 1 wherein for each of select ones of said calibration points the calibration data includes plural data vectors and the evaluating of said calibration data comprises a determination of clustering of said plural data vectors.

8. The method of claim 1 wherein the step of estimating the location of a mobile device further comprises estimating the location of a mobile device as the centroid of said intersection.

9. The method of claim 1 wherein the step of estimating the location of a mobile device further comprises estimating the location of a mobile device as a function of a statistical measure for calibration data of select ones of said calibration points.

10. The method of claim 9 wherein said statistical measure is a probability density function.

11. The method of claim 1 wherein the step of determining an intersection further comprises determining an intersection of each defined region as a function of a distortion measure.

12. The method of claim 1 further comprising the step of:

(h) examining subsets of available network measurement reports for an intersection.

13. A method of estimating the location of a mobile device in a geographic region comprising the steps of:

(a) providing calibration data for each of one or more calibration points in a geographic region, said calibration data including at least one characterizing parameter

(b) receiving a network measurement report from a mobile device at an unknown location, said network measurement report also including at least one characterizing parameter;

(c) defining a first region within said calibration data as a function of a first characterizing parameter of said network measurement report and a predetermined range of said first parameter;

(d) defining a second region within said calibration data as a function of another characterizing parameter of said network measurement report and a predetermined range of said another parameter;

(e) repeating steps (c)-(d) for each characterizing parameter in said network measurement report;

(f) determining an intersection of each defined region; and

(g) estimating the location of a mobile device in said geographic region as a function of said intersection,

wherein the step of estimating the location of a mobile device comprises:

(i) comparing an ordered list of cells neighboring a cell serving said mobile device in said network measurement report to an ordered list of neighboring cells in each calibration point of said intersection, said ordering being a function of any parameter of said network measurement report;

(ii) if no exact match is made between the ordered list of neighboring cells of said network measurement report and any calibration point in said intersection then forming a largest subset of the ordered list of neighboring cells in said calibration points that provide a match; and

(iii) generating an estimated location of said mobile device wherein said estimated location is selected from the group consisting of: a centroid of a cluster of matching calibration points in said intersection; a highest joint probability matching calibration point in said intersection; a weighted sum of the locations of a set of matching calibration points in said intersection; a weighted sum of clustered locations of a set of matching calibration points in said intersection; and as a function of estimated locations determined from a subset of said network measurement report.

14. The method of claim 13 wherein one of said calibration points is located on a predetermined fixed uniform grid defined over said geographic region.

15. The method of claim 13 wherein one of said calibration points is randomly located within said geographic region.

16. The method of claim 13 wherein said calibration data comprises information from at least one network measurement report having a known location.

17. The method of claim 13 wherein said calibration data for one of said calibration points is obtained from one or more mobile devices located in close proximity to said one calibration point.

18. The method of claim 13 wherein said calibration data for one of said calibration points is obtained from a signal transmitted from a mobile device in close proximity to said one calibration point and received at a receiver in or in proximity to said geographic region.

19. The method of claim 13 wherein for each of select ones of said calibration points the calibration data includes plural data vectors and the evaluating of said calibration data comprises a determination of clustering of said plural data vectors.

20. The method of claim 13 wherein the step of determining an intersection further comprises determining an intersection of each defined region as a function of a distortion measure.

21. The method of claim 17 wherein said distortion measure is a Mahalanobis distance.

22. A method of estimating the location of a mobile device in a geographic region comprising the steps of:

(a) providing calibration data for each of one or more calibration points in a geographic region, said calibration data including at least one characterizing parameter

(b) receiving a network measurement report from a mobile device at an unknown location, said network measurement report also including at least one characterizing parameter;

(c) defining a first region within said calibration data as a function of a first characterizing parameter of said network measurement report and a predetermined range of said first parameter;

(d) defining a second region within said calibration data as a function of another characterizing parameter of said network measurement report and a predetermined range of said another parameter;

(e) repeating steps (c)-(d) for each characterizing parameter in said network measurement report;

(f) determining an intersection of each defined region; and

(g) estimating the location of a mobile device in said geographic region as a function of said intersection,

wherein the step of estimating the location of a mobile device comprises:

(i) comparing an ordered list of cells neighboring a cell serving said mobile device in said network measurement report to an ordered list of neighboring cells in each calibration point of said intersection, said ordering being a function of any parameter of said network measurement report;

(ii) if the ordered list of neighboring cells of said network measurement report is not contained in the ordered list of neighboring cells for said intersection then using a largest subset of ordered neighboring cells in said network measurement report having either an exact match or contained in the ordered list of neighboring cells in said intersection; and

(iii) generating an estimated location of said mobile device wherein said estimated location is selected from the group consisting of: a centroid of a cluster of matching calibration points in said intersection; a highest joint probability matching calibration point in said intersection; a weighted sum of the locations of a set of matching calibration points in said intersection; a weighted sum of clustered locations of a set of matching calibration points in said intersection; and as a function of estimated locations determined from a subset of said network measurement report.

23. The method of claim 22 wherein one of said calibration points is located on a predetermined fixed uniform grid defined over said geographic region.

24. The method of claim 22 wherein one of said calibration points is randomly located within said geographic region.

25. The method of claim 22 wherein said calibration data comprises information from at least one network measurement report having a known location.

26. The method of claim 22 wherein said calibration data for one of said calibration points is obtained from one or more mobile devices located in close proximity to said one calibration point.

27. The method of claim 22 wherein said calibration data for one of said calibration points is obtained from a signal transmitted from a mobile device in close proximity to said one calibration point and received at a receiver in or in proximity to said geographic region.

28. The method of claim 22 wherein for each of select ones of said calibration points the calibration data includes plural data vectors and the evaluating of said calibration data comprises a determination of clustering of said plural data vectors.

29. The method of claim 22 wherein the step of determining an intersection further comprises determining an intersection of each defined region as a function of a distortion measure.

30. A method of estimating the location of a mobile device in a geographic region comprising the steps of:

(a) providing calibration data for each of one or more calibration points in a geographic region, said calibration data including at least one characterizing parameter

(b) receiving a network measurement report from a mobile device at an unknown location, said network measurement report also including at least one characterizing parameter;

(c) defining a first region within said calibration data as a function of a first characterizing parameter of said network measurement report and a predetermined range of said first parameter;

(d) defining a second region within said calibration data as a function of another characterizing parameter of said network measurement report and a predetermined range of said another parameter;

(e) repeating steps (c)-(d) for each characterizing parameter in said network measurement report;

(f) determining an intersection of each defined region; and

(g) estimating the location of a mobile device in said geographic region as a function of said intersection,

wherein the step of estimating the location of a mobile device comprises:

(i) evaluating a probability density function for each power level of a cell neighboring a cell serving said mobile device in said network measurement report over each calibration point in a set of available calibration points in said intersection;

(ii) determining a joint probability as a function of said individual probability density functions; and

(iii) generating an estimated location of said mobile device wherein said estimated location is selected from the group consisting of: a highest joint probability matching calibration point in said intersection; a weighted sum of the locations of a set of matching calibration points in said intersection; a weighted sum of clustered locations of a set of matching calibration points in said intersection; and as a function of estimated locations determined from a subset of said network measurement report.

31. The method of claim 30 wherein one of said calibration points is located on a predetermined fixed uniform grid defined over said geographic region.

32. The method of claim 30 wherein one of said calibration points is randomly located within said geographic region.

33. The method of claim 30 wherein said calibration data comprises information from at least one network measurement report having a known location.

34. The method of claim 30 wherein said calibration data for one of said calibration points is obtained from one or more mobile devices located in close proximity to said one calibration point.

35. The method of claim 30 wherein said calibration data for one of said calibration points is obtained from a signal transmitted from a mobile device in close proximity to said one calibration point and received at a receiver in or in proximity to said geographic region.

36. The method of claim 30 wherein for each of select ones of said calibration points the calibration data includes plural data vectors and the evaluating of said calibration data comprises a determination of clustering of said plural data vectors.

37. The method of claim 30 wherein the step of determining an intersection further comprises determining an intersection of each defined region as a function of a distortion measure.

38. A method of estimating the location of a mobile device in a geographic region comprising the steps of:

(a) providing calibration data for each of one or more calibration points in a geographic region, said calibration data including at least one characterizing parameter

(b) receiving a network measurement report from a mobile device at an unknown location, said network measurement report also including at least one characterizing parameter;

(c) defining a first region within said calibration data as a function of a first characterizing parameter of said network measurement report and a predetermined range of said first parameter;

(d) defining a second region within said calibration data as a function of another characterizing parameter of said network measurement report and a predetermined range of said another parameter;

(e) repeating steps (c)-(d) for each characterizing parameter in said network measurement report;

(f) determining an intersection of each defined region; and

(g) estimating the location of a mobile device in said geographic region as a function of said intersection,

wherein the step of estimating the location of a mobile device comprises:

(i) evaluating a joint probability of power levels for at least one cell neighboring a cell serving said mobile device in said network measurement report over a set of available calibration points in said intersection; and

(ii) generating an estimated location of said mobile device wherein said estimated location is selected from the group consisting of: a highest joint probability matching calibration point in said intersection; a weighted sum of the locations of a set of matching calibration points in said intersection; a weighted sum of clustered locations of a set of matching calibration points in said intersection; and as a function of estimated locations determined from a subset of said network measurement report.

39. The method of claim 38 wherein one of said calibration points is located on a predetermined fixed uniform grid defined over said geographic region.

40. The method of claim 38 wherein one of said calibration points is randomly located within said geographic region.

41. The method of claim 38 wherein said calibration data comprises information from at least one network measurement report having a known location.

42. The method of claim 38 wherein said calibration data for one of said calibration points is obtained from one or more mobile devices located in close proximity to said one calibration point.

43. The method of claim 38 wherein said calibration data for one of said calibration points is obtained from a signal transmitted from a mobile device in close proximity to said one calibration point and received at a receiver in or in proximity to said geographic region.

44. The method of claim 38 wherein for each of select ones of said calibration points the calibration data includes plural data vectors and the evaluating of said calibration data comprises a determination of clustering of said plural data vectors.

45. The method of claim 38 wherein the step of determining an intersection further comprises determining an intersection of each defined region as a function of a distortion measure.

46. A method of estimating the location of a mobile device in a geographic region comprising the steps of:

(a) providing calibration data for each of one or more calibration points in a geographic region, said calibration data including at least one characterizing parameter

(b) receiving a network measurement report from a mobile device at an unknown location, said network measurement report also including at least one characterizing parameter;

(c) defining a first region within said calibration data as a function of a first characterizing parameter of said network measurement report and a predetermined range of said first parameter;

(d) defining a second region within said calibration data as a function of another characterizing parameter of said network measurement report and a predetermined range of said another parameter;

(e) repeating steps (c)-(d) for each characterizing parameter in said network measurement report;

(f) determining an intersection of each defined region; and

(g) estimating the location of a mobile device in said geographic region as a function of said intersection,

wherein the step of estimating the location of a mobile device comprises:

(i) determining a distortion measure between a parameter or function of a calibration point and a corresponding parameter or function in said network measurement report; and

(ii) generating an estimated location of said mobile device wherein said estimated location is selected from the group consisting of: a location of a calibration point having the smallest distortion measure; a weighting of the locations of a set of matching calibration points in said intersection, said weighting being a function of said distortion measure; a weighted sum of clustered locations of a set of matching calibration points in said intersection; and as a function of estimated locations determined from a subset of said network measurement report.

47. The method of claim 46 wherein one of said calibration points is located on a predetermined fixed uniform grid defined over said geographic region.

48. The method of claim 46 wherein one of said calibration points is randomly located within said geographic region.

49. The method of claim 46 wherein said calibration data comprises information from at least one network measurement report having a known location.

50. The method of claim 46 wherein said calibration data for one of said calibration points is obtained from one or more mobile devices located in close proximity to said one calibration point.

51. The method of claim 46 wherein said calibration data for one of said calibration points is obtained from a signal transmitted from a mobile device in close proximity to said one calibration point and received at a receiver in or in proximity to said geographic region.

52. The method of claim 46 wherein for each of select ones of said calibration points the calibration data includes plural data vectors and the evaluating of said calibration data comprises a determination of clustering of said plural data vectors.

53. The method of claim 46 wherein the step of determining an intersection further comprises determining an intersection of each defined region as a function of a distortion measure.

54. A method of estimating the location of a mobile device in a geographic region comprising the steps of:

(a) providing calibration data for each of one or more calibration points in a geographic region, said calibration data including at least one characterizing parameter

(b) receiving a network measurement report from a mobile device at an unknown location, said network measurement report also including at least one characterizing parameter;

(c) defining a first region within said calibration data as a function of a first characterizing parameter of said network measurement report and a predetermined range of said first parameter;

(d) defining a second region within said calibration data as a function of another characterizing parameter of said network measurement report and a predetermined range of said another parameter;

(e) repeating steps (c)-(d) for each characterizing parameter in said network measurement report;

(f) determining an intersection of each defined region; and

(g) estimating the location of a mobile device in said geographic region as a function of said intersection,

wherein the step of estimating the location of a mobile device comprises:

(i) matching cell power ordering of cells neighboring a cell serving said mobile device in said network measurement report to neighboring cell power ordering of calibration points in each of the calibration points in said intersection; and

(ii) selecting an estimated location as a function of a quality of said matching,

and wherein said quality is a function of a relative shift in an ordering sequence occurring between said network measurement report and calibration point cell power ordering.

55. The method of claim 54 wherein one of said calibration points is located on a predetermined fixed uniform grid defined over said geographic region.

56. The method of claim 54 wherein one of said calibration points is randomly located within said geographic region.

57. The method of claim 54 wherein said calibration data comprises information from at least one network measurement report having a known location.

58. The method of claim 54 wherein said calibration data for one of said calibration points is obtained from one or more mobile devices located in close proximity to said one calibration point.

59. The method of claim 54 wherein said calibration data for one of said calibration points is obtained from a signal transmitted from a mobile device in close proximity to said one calibration point and received at a receiver in or in proximity to said geographic region.

60. The method of claim 54 wherein for each of select ones of said calibration points the calibration data includes plural data vectors and the evaluating of said calibration data comprises a determination of clustering of said plural data vectors.

61. The method of claim 54 wherein the step of determining an intersection further comprises determining an intersection of each defined region as a function of a distortion measure.

Assignments (20)
RELEASE OF SECURITY INTEREST AT REEL/FRAME 049905/0504 Recorded Dec 19, 2024
From: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
To: ARRIS ENTERPRISES LLC (F/K/A ARRIS ENTERPRISES, INC.); ARRIS TECHNOLOGY, INC.; ARRIS SOLUTIONS, INC.; COMMSCOPE, INC. OF NORTH CAROLINA; COMMSCOPE TECHNOLOGIES LLC; RUCKUS WIRELESS, LLC (F/K/A RUCKUS WIRELESS, INC.)
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PARTIAL TERMINATION AND RELEASE OF SECURITY INTEREST IN PATENTS RECORDED AT R/F 060752/0001 Recorded Apr 13, 2023
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To: COMMSCOPE TECHNOLOGIES LLC; COMMSCOPE, INC. OF NORTH CAROLINA; ARRIS ENTERPRISES LLC
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From: WILMINGTON TRUST, NATIONAL ASSOCIATION
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From: BISON PATENT LICENSING, LLC
To: GEOSCOPE TECHNOLOGIES PTE. LTD.
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ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 13, 2022
From: COMMSCOPE, INC. OF NORTH CAROLINA
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PARTIAL TERMINATION AND RELEASE OF SECURITY INTEREST IN PATENTS Recorded Jul 15, 2022
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To: COMMSCOPE TECHNOLOGIES LLC; ARRIS ENTERPRISES LLC; COMMSCOPE, INC. OF NORTH CAROLINA
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PARTIAL RELEASE OF ABL SECURITY INTEREST Recorded Jul 13, 2022
From: JPMORGAN CHASE BANK, N.A.
To: COMMSCOPE TECHNOLOGIES LLC; ARRIS ENTERPRISES LLC; COMMSCOPE, INC. OF NORTH CAROLINA
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PARTIAL RELEASE OF TERM LOAN SECURITY INTEREST Recorded Jul 13, 2022
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SECURITY INTEREST Recorded Nov 19, 2021
From: ARRIS SOLUTIONS, INC.; ARRIS ENTERPRISES LLC; COMMSCOPE TECHNOLOGIES LLC; COMMSCOPE, INC. OF NORTH CAROLINA; RUCKUS WIRELESS, INC.
To: WILMINGTON TRUST
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TERM LOAN SECURITY AGREEMENT Recorded Jul 3, 2019
From: COMMSCOPE, INC. OF NORTH CAROLINA; COMMSCOPE TECHNOLOGIES LLC; ARRIS ENTERPRISES LLC; ARRIS TECHNOLOGY, INC.; RUCKUS WIRELESS, INC.; ARRIS SOLUTIONS, INC.
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PATENT SECURITY AGREEMENT Recorded Jul 3, 2019
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ABL SECURITY AGREEMENT Recorded Jul 3, 2019
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RELEASE OF SECURITY INTEREST Recorded Apr 9, 2019
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RELEASE OF SECURITY INTEREST Recorded Apr 9, 2019
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RELEASE OF SECURITY INTEREST PATENTS (RELEASES RF 036201/0283) Recorded Mar 31, 2017
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PATENT SECURITY AGREEMENT (TL) Recorded Sep 25, 2012
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PATENT SECURITY AGREEMENT (ABL) Recorded Sep 24, 2012
From: ALLEN TELECOM LLC; ANDREW LLC; COMMSCOPE, INC. OF NORTH CAROLINA
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Continuity (3)
Continuation 12023841 · Jan 31, 2008
Provisional Application 60899379 · Feb 5, 2007
Related Publication 20120302252A1 · Nov 29, 2012