Mapping patterns of movement based on the aggregation of spatial information contained in wireless transmissions

• US 6,975,939 B2
• Filed: 07/29/2002
• Issued: 12/13/2005
• Est. Priority Date: 07/29/2002
• Status: Expired due to Fees

• Current Assignee: Government of the United States of America, United States Secretary of the Army
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Simpson, R. Justin, Edwards, Daniel L.
• Primary Examiner(s): Corsaro, Nick
• Assistant Examiner(s): Perez, Angelica
• Application Number:
  US10/206,757
• Publication Number:
  US 20030050754A1
• Time in Patent Office: 1,233 Days
• Field of Search: 701/200, 701/201, 701/208, 701/209, 701/214
• US Class Current: 701/209
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements

Abstract

Time-tagged coordinates from session-unique transmissions of wireless devices are collected routinely and stored for later analysis. From this data, one may derive a sequence of wireless device operation from which attributes may be ascertained. Sequences are accumulated until a dense aggregate pattern (900) is formed over a geographic area. Aggregate data is sorted into ranges representing speed of movement and then converted to pixels representing cells (401) in an aggregate matrix (400). Heavily weighted values (402) are assigned to cells (401) that represent a location within a pre-specified spatial error (100) about a data point (101). Lower values are assigned to cells (401) representing paths (200), or corridors, connecting these better-identified locations. As more transmission sessions (500) are added to the matrix (400), the largest weight values (402) cluster as individual cells (401) representing a most likely path (1001). Thus precise topographic attributes may be derived based on these spatial clusters (FIG. 11A), overlapping paths connecting them (1001), or combinations (FIG. 15A) thereof.

Claims

1. A method of attaining spatial precision in mapping patterns by using data collected from uniquely identified wireless transmissions sessions, comprising:

identifying a source of said routinely collected data,

wherein said data includes data points describing spatial information, and

wherein each said data point is time-tagged, and

wherein each said time-tagged data point is uniquely attributable to one said transmission session;

selecting pre-specified portions of said data points collected from a pre-specified geographic area,

wherein said data points may be available from storage devices;

acquiring said pre-specified portions of said data points;

estimating the spatial error about each said data point,

wherein said ascertaining of said spatial error may depend on the status of a wireless device or the method of obtaining location data on a position of a wireless device at a particular time of transmission;

sorting said data points by said unique transmission session identifiers;

calculating at least one speed, if any, to be assigned each said transmission session for whom said data points are associated,

wherein said speed is calculated by dividing a distance interval between successive said data points by an associated time interval, Δ

T, and

wherein said speed is assigned to one of a pre-specified range of speeds, and

wherein Δ

T represents the time of occurrence of a second transmission of a unique transmission session minus the time of occurrence of a first transmission immediately preceding said second transmission of said unique transmission session;

sorting said data according to said pre-specified ranges of speed,

wherein said sorting differentiates categories of said transmission sessions;

converting said representation of said at least one transmission session to weighted cells;

adding said weighted cells of said at least one transmission session to at least one aggregation matrix;

aggregating said weighted cells based on identifying clusters of said data points,

wherein said clusters may have a linear or areal shape, or a combination thereof;

converting said cell aggregate to at least one vector representation;

sorting said data according to pre-specified time intervals;

ascertaining at least one attribute of each said at least one vector representation; and

from said at least one attribute of each said at least one vector representation, assigning a most likely attribute,

wherein said most likely attributes are used to map a precise pattern.

2. The method of claim 1 further comprising calculating historical patterns of activity of said uniquely identified wireless transmission sessions based on at least one said pre-specified time interval.

3. The method of claim 1 further comprising steps to be undertaken after sorting said data according to said pre-specified ranges of speed and before said converting said representation of said at least one transmission session to said weighted cells, said steps comprising:

representing said data from a pair of two successive said uniquely identified wireless transmissions as a transmission corridor; and

assembling multiple said transmission corridors, as available, into said at least one transmission session.

4. The method of claim 1 in which said aggregating of said weighted cells is based on spatial clustering of said data points.

5. The method of claim 1 in which said aggregation of said weights is based on connectivity of said data points, wherein said connectivity may be linear or areal, or a combination thereof.

6. The method of claim 1 in which the cell size is no larger than one-half the resolution of the positional accuracy of the spatial coordinates provided in association with said uniquely identified wireless transmission sessions.

7. The method of claim 1 in which said results may be stored prior to mapping said precise pattern.

8. The method of claim 1 in which said results are used to compose precise topographic maps.

9. The method of claim 1 in which said precise patterns may be mapped by manipulating data representing wireless transmissions from sources on conveyances selected from the group consisting of:

land-based vehicles, airborne vehicles, waterborne vehicles, space borne vehicles, remotely controlled objects, humans, and animals, and combinations thereof, such as a human on horseback or a human riding in a bus while moving about therein.

10. The method of claim 1 in which said spatial precision is attained in each of three dimensions as referenced to any datum.

11. The method of claim 1 in which said spatial precision is attained in each of two dimensions as referenced to any datum.

12. The method of claim 1 in which said wireless transmissions originate from devices selected from the group consisting essentially of:

cellular telephones, laptop computers, personal digital assistants (PDAs), portable communications devices, geopositioning systems, LORAN®

, Global Positioning Systems (GPS), beacons, alarms, security systems, and combinations thereof.

13. The method of claim 1 in which said at least one attribute is ascertained by reference to at least one stored library of attributes.

14. The method of claim 13 in which said at least one stored library of attributes is at least one look-up table.

15. A method of developing precise topographic maps by using data routinely collected from uniquely identified wireless transmissions sessions, comprising:

identifying a source of said routinely collected data,

wherein said data includes data points describing spatial information, and

wherein each said data point is time-tagged, and

wherein each said time-tagged data point is uniquely attributable to one said transmission session;

selecting pre-specified portions of said data points collected from a pre-specified geographic area,

wherein said data points may be available from storage devices;

acquiring said pre-specified portions of said data points;

estimating the spatial error about each said data point,

wherein said ascertaining of said spatial error may depend on the status of a wireless device or the method of obtaining location data on a position of a wireless device at a particular time of transmission;

sorting said data points by said unique transmission session identifiers;

calculating at least one speed, if any, to be assigned each said uniquely identified wireless transmission session for whom said data points are associated,

wherein said speed is calculated by dividing a distance interval between successive said data points by an associated time interval, Δ

T, and

wherein said speed is assigned to one of a pre-specified range of speeds, and

wherein Δ

T represents the time of occurrence of a second transmission of said uniquely identified wireless transmission session minus the time of occurrence of a first transmission immediately preceding said second transmission of said uniquely identified wireless transmission session;

sorting said data according to said pre-specified ranges of speed,

wherein said sorting differentiates categories of said uniquely identified wireless transmission sessions;

converting said representation of said at least one uniquely identified wireless transmission session to weighted cells;

adding said weighted cells of said at least one uniquely identified wireless transmission session to said aggregation matrix;

aggregating said weighted cells based on identifying clusters of said data points,

wherein said clusters may have a linear or areal shape, or a combination thereof;

converting said weighted cell aggregate to at least one vector representation;

sorting said data according to at least one pre-specified time interval;

ascertaining at least one attribute of each said at least one vector representation; and

from said at least one attribute of each said at least one vector representation, assigning a most likely attribute,

wherein a collection of said most likely attributes is used to develop a precise topographic map.

16. The method of claim 15 further comprising calculating historical patterns of uniquely identified wireless transmission activity based on at least one said at least one pre-specified time interval.

17. The method of claim 15 further comprising steps to be undertaken after sorting said data according to said pre-specified ranges of speed and before said converting said representation of said at least one transmission session to weighted cells, said steps comprising:

representing said data from a pair of two successive said uniquely identified transmissions as a transmission corridor; and

assembling multiple said transmission corridors, as available, into said at least one transmission session.

18. The method of claim 15 in which said aggregating of said weighted cells is based on spatial clustering of said data points.

19. The method of claim 15 in which said aggregation of said weights is based on connectivity of said data points, wherein said connectivity may be linear or areal, or a combination thereof.

20. The method of claim 15 in which the cell size is no larger than one-half the resolution of the positional accuracy of the spatial coordinates provided in association with said uniquely identified wireless transmission sessions.

21. The method of claim 15 in which said results may be stored prior to developing said topographic map.

22. The method of claim 15 in which said precise maps are developed by manipulating data representing wireless transmissions from sources on conveyances selected from the group consisting of:

land-based vehicles, airborne vehicles, waterborne vehicles, space borne vehicles, remotely controlled objects, humans, and animals, and combinations thereof, such as a human on horseback or a human riding in a bus while moving about therein.

23. The method of claim 15 in which said topographic map is developed in each of three dimensions as referenced to any datum.

24. The method of claim 15 in which said topographic map is developed in each of two dimensions as referenced to any datum.

25. The method of claim 15 in which said wireless transmissions originate from devices selected from the group consisting essentially of:

cellular telephones, laptop computers, personal digital assistants (PDAs), portable communications devices, geopositioning systems, LORAN®

, Global Positioning Systems (GPS), beacons, alarms, security systems, and combinations thereof.

26. The method of claim 15 in which said at least one attribute is ascertained by reference to at least one stored library of attributes.

27. The method of claim 26 in which said at least one stored library of attributes is at least one look-up table.