Location system

• US 20050128143A1
• Filed: 10/20/2004
• Published: 06/16/2005
• Est. Priority Date: 10/20/2003
• Status: Active Grant

• Current Assignee: Consortium P Incorporated
• Original Assignee: Radianse Incorporated (Airpointe Corp.)
• Inventors: Lathrop, Olin, Dempsey, Michael K., Gaudet, Phil
• Granted Patent: US 7,053,831 B2
• Time in Patent Office: Days
• US Class Current: 342/463
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial

Abstract

Systems and methods for allowing the location of transmitter to be determined (approximated) without requiring its distance from a receiver to be precisely known. Methods for determining a location of a transmitter without precise distance calculations. In one embodiment, a method is disclosed having the steps of: for a receiver, estimate a first zone a first transmitter is in; for remaining receivers that can receive a given transmitter, each estimate a second zone a first transmitter is in; and determine if there are overlaps in any of the zones. In another embodiment a potential target area is defined wherein the location of a transmitter can estimated.

Claims

1. A method for determining location of an object, comprising the steps of:

determining a potential target area; and

estimating a target location within the potential target area.

2. The method of claim 1, wherein the step of determining a potential target area comprises the steps of:

identifying receivers that received a signal from a transmitter;

generating one or more line segments connecting the identified receivers;

determining zones around identified receivers;

generating lines through intersections of zones and the one ore more lines; and

designating the area defined by secants as the potential target area.

3. The method of claim 2, wherein the step of generating lines comprises generating secants through the intersections between the line segments and the zones for each zone.

4. The method of claim 2, wherein the step of generating lines comprises generating tangents at the intersections between the line segments and the zones for each zone.

5. The method of claim 2, wherein said zones are rings.

6. The method of claim 2, wherein said zone is defined as a sphere.

7. The method of claim 2, wherein a size of said zones is scalable

8. The method of claims 2, wherein said zones are determined using received signal strength indication.

9. The method of claims 1, wherein said zones are determined using time of arrival of one or more signals.

10. The method of claim 1, wherein the step of estimating a target location within the potential target area comprises finding the center of the potential target area.

11. The method of claim 1, wherein the step of determining a potential target area comprises the steps of:

for a receiver, estimating a first zone within which a first transmitter is located;

for remaining receivers that can detect a given transmitter, each estimating a second zone within which a first transmitter is located; and

determining if there are overlaps in any of the zones.

12. A method for determining location of an object, comprising the steps of:

for a receiver, estimating a first zone within which a first transmitter is located;

for remaining receivers that can detect a given transmitter, each estimating a second zone within which a first transmitter is located; and

determining if there are overlaps in any of the zones.

13. The method of claim 12, wherein said estimation steps yield a vector (Zn-m)₁, (Zn-m)₂, (Zn-m)₃ . . . (Zn-m)_P where P is the number of receivers that can hear said first transmitter.

14. The method of claim 12, wherein said zone is defined as a ring.

15. The method of claim 12, wherein said receiver has a plurality of zones each defined as a ring.

16. The method of claim 12, wherein said plurality of zones are defined as concentric rings.

17. The method of claim 12, wherein said zone is defined as a sphere.

18. The method of claim 12, wherein said receiver has a plurality of zones each defined as a sphere.

19. The method of claim 12, wherein said plurality of zones are defined as concentric spheres.

20. The method of claim 12, wherein a size of said zones is scalable.

21. The method of claims 12, wherein said estimation steps use received signal strength indication to determine location.

22. The method of claims 12, wherein said estimation steps use time of arrival of one or more signals to determine location.

23. A method for determining location of an object, comprising the steps of:

identifying receivers that received a signal from a transmitter;

generating one or more lines segments connecting the identified receivers;

determining zones around the identified receivers;

generating lines through intersections of zones and the one ore more line segments;

designating the area defined by the lines as the potential target area; and

determining center of potential target area.

24. The method of claim 23, wherein the step of generating lines comprises generating secants through the intersections between the line segments and the zones for each zone.

25. The method of claim 23, wherein the step of generating lines comprises generating tangents at the intersections between the line segments and the zones for each zone.

26. The method of claim 23, wherein said zone is defined as a ring.

27. The method of claim 23, wherein said zone is defined as a sphere.

28. The method of claim 23, wherein a size of said zones is scalable.

29. The method of claims 23, wherein said zones are determined using received signal strength indication.

30. The method of claims 23, wherein said zones are determined using time of arrival of one or more signals.

31. In a computing device, a method for determining location of an object, comprising the steps of:

for a receiver, estimating a first zone within which a first transmitter is located;

for remaining receivers that can receive a given transmitter, each estimating a second zone within which a first transmitter is located; and

determining if there are overlaps in any of the zones.

32. In a computing device, a method for determining location of an object, comprising the steps of:

identifying receivers that received a signal from a transmitter;

generating one or more line segments connecting the identified receivers;

determining zones around the identified receivers;

generating lines through intersections of zones and the one ore more line segments;

designating the area defined by lines as the potential target area; and

determining the center of the potential target area.

33. A computer program product holding instructions executable in a computer for determining location of an object, the instructions comprising the steps of:

for a receiver, estimating a first zone within which a first transmitter is located;

for remaining receivers that can receive a given transmitter, each estimating a second zone within which a first transmitter is located; and

determining if there are overlaps in any of the zones.

34. A computer program product holding instructions executable in a computer for determining location of an object, the instructions comprising the steps of:

identifying receivers that received a signal from a transmitter;

generating one or more line segments connecting the identified receivers;

determining zones around the identified receivers;

generating lines through intersections of zones and the one ore more line segments;

designating the area defined by lines as the potential target area; and

determining the center of the potential target area.

35. In a location system comprising at least one transmitter and at least two receivers, a method comprising:

determining which receivers can receive a signal from the transmitter;

estimating the zones of the receivers the transmitter is in;

determining if there are overlaps in any of the zones.

36. The method of claim 35 further comprising the step of determining the area of overlap between zones.

37. The method of claim 35 further comprising the step of determining the volume of overlap between zones.

38. A location system for determining location of an object, comprising a location determination module for determining a potential target area encompassing the object, and estimating the location of the object within the potential target area.

39. The location system of claim 38, wherein the location determining module comprises a receiver.

40. The location system of claim 38, wherein the location determining module comprises a network.

41. The location system of claim 38, wherein the location determining module comprises a network connection element.

42. The location system of claim 38, wherein the location determining module comprises a location resolver.