Estimating the Location of a Wireless Terminal Based on Non-Uniform Locations

• US 20060240843A1
• Filed: 05/22/2006
• Published: 10/26/2006
• Est. Priority Date: 05/22/2006
• Status: Active Grant

• Current Assignee: Polaris Wireless Incorporated
• Original Assignee: Polaris Wireless Incorporated
• Inventors: Dressler, Robert Morris, Spain, David Stevenson Jr., Feuerstein, Martin
• Granted Patent: US 7,753,278 B2
• Time in Patent Office: Days
• US Class Current: 455/456.100
• CPC Class Codes: G01S 5/02521 using a radio-map
• 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 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A technique for estimating the location of a wireless terminal at an unknown location in a geographic region is disclosed. The technique is based on the recognition that there are traits of electromagnetic signals that are dependent on topography, the receiver, the location of the transmitter, and other factors. For example, if a particular radio station is known to be received strongly at a first location and weakly at a second location, and a given wireless terminal at an unknown location is receiving the radio station weakly, it is more likely that the wireless terminal is at the second location than at the first location.

Claims

11. A method comprising:

modeling an environment as a plurality of locations, wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the physical attributes of said environment; and

estimating the location of a wireless terminal in said environment based on comparing a measurement of a trait of a signal processed by said wireless terminal to an expected value of said trait for one or more of a plurality of locations.

12. The method of claim 11 wherein the description of each of said locations comprises latitude, longitude, and altitude.

13. The method of claim 11 wherein the scope of at least two of said locations overlap for at least one, but not all, points of latitude and longitude.

14. The method of claim 11 wherein the scope of at least two of said locations overlap at all points of latitude and longitude.

15. The method of claim 11 further comprising generating an adjacency graph of said locations.

16. The method of claim 11 wherein said plurality of locations represent an overpass and an underpass.

17. The method of claim 11 wherein said plurality of locations represent a multi-story building.

18. The method of claim 11 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on legal laws governing geographic region 220.

19. The method of claim 11 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the calendrical time T.

20. The method of claim 11 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the environmental conditions N.

21. A method comprising estimating the location of a wireless terminal in a geographic region environment based on comparing a measurement of a trait of a signal processed by said wireless terminal to an expected value of said trait for one or more of a plurality of locations;

wherein the boundaries of one or more of said plurality of locations are based, at least in part, on theoretical predictions and empirical data regarding the location and movement of individuals and groups of people and vehicles in geographic region 220.

1. A method comprising estimating the location of a wireless terminal in a geographic region environment based on comparing a measurement of a trait of a signal processed by said wireless terminal to an expected value of said trait for one or more of a plurality of locations;

wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the physical attributes of said environment.

2. The method of claim 1 wherein the description of each of said locations comprises latitude, longitude, and altitude.

3. The method of claim 1 wherein the scope of at least two of said locations overlap for at least one, but not all, points of latitude and longitude.

4. The method of claim 1 wherein the scope of at least two of said locations overlap at all points of latitude and longitude.

5. The method of claim 1 further comprising generating an adjacency graph of said locations.

6. The method of claim 1 wherein said plurality of locations represent an overpass and an underpass.

7. The method of claim 1 wherein said plurality of locations represent a multi-story building.

8. The method of claim 1 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on legal laws governing geographic region 220.

9. The method of claim 1 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the calendrical time T.

10. The method of claim 1 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the environmental conditions N.

22. The method of claim 21 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on legal laws governing geographic region 220.

23. The method of claim 21 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the calendrical time T.

24. The method of claim 21 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the environmental conditions N.

24-1. The method of claim 21 wherein the boundaries of one or more of said plurality of locations are based, at least in part, on the physical attributes of said environment.