Method and system for indoor RF mapping

• US 8,666,432 B2
• Filed: 08/13/2012
• Issued: 03/04/2014
• Est. Priority Date: 08/11/2011
• Status: Active Grant

• Current Assignee: Blue Ocean Robotics ApS
• Original Assignee: RF Spot Inc.
• Inventors: Gold, Andrew Joseph, Freedman, Gordon Sean
• Primary Examiner(s): Ly, Nghi H
• Application Number:
  US13/572,996
• Publication Number:
  US 20130095848A1
• Time in Patent Office: 568 Days
• Field of Search: 455/456.1, 455/404.2, 455/414.1, 455/423, 455/418, 455/421
• US Class Current: 455/456.1
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 4/33 for indoor environments, e.g. buildings

Abstract

A method is disclosed for determining a location of a mobile electronic device. The mobile electronic device receives an RF signal providing RF fingerprint data and receives a third party location estimate from a third party service. Location data is collected by a dead reckoning system and corresponds to RF fingerprint data and third party estimates collected for a plurality of locations. A correlation between the RF fingerprint data, the third party location estimates, and location data is determined providing a transform for transforming the third party location estimates into a more accurate location estimate of the mobile electronic device.

Claims

1. A method comprising:

providing RF (radio frequency) fingerprint data related to each of a plurality of locations wherein the plurality of locations comprises a first location;

at each of the plurality of locations;

receiving from a third party location estimate data based on sensed signals;

sensing location data indicative of a geographical location;

processing the RF fingerprint data, the third party, location estimate data, and the location data to determine correlation data, comprising a first transforming for transforming the third party location estimate data to determine second location estimate data; and

storing the third party location estimate data and the correlation data for each of the plurality of locations.

2. A method according to claim 1 wherein the location data comprises data indicative of a relative displacement captured using a first system comprising a dead reckoning system.

3. A method according to claim 1 wherein the RF fingerprint data comprises data indicative of a sensed RF signal comprising a wireless signal according to a first standard and a wireless signal according to a second standard, the first standard other than the second standard, and the first standard and second standard other than a Global Positioning System standard.

4. A method according to claim 1 wherein sensing the location data comprises determining a first position using a Global Positioning System standard, the relative displacement relative to the first position.

5. A method according to claim 2 wherein the dead reckoning system comprises a distance sensor.

6. A method according to claim 5 wherein the distance sensor is a non-contact distance sensor.

7. A method according to claim 5 wherein the distance sensor comprises optically encoded wheels.

8. A method according to claim 2 comprising:

detecting an error in the location data captured by the dead reckoning system; and

applying a corrective function to the location data to compensate for the error.

9. A method according to claim 1 comprising sensing altitude of the first location to provide altitude data.

10. A method according to claim 9 comprising applying a compensation function to the location data for errors based on changes in altitude.

11. A method according to claim 1 wherein the correlation data comprising the first transform is associated with a defined area.

12. A method according to claim 11 wherein the defined area is a building.

13. A method according to claim 11 wherein the defined area is a room.

14. A method according to claim 1 wherein the transform comprises a mathematical function.

15. A method according to claim 1 wherein the transform comprises a process.

16. A method according to claim 15 wherein the process is iterative.

17. A method according to claim 1 wherein the correlation data comprises a plurality of transforms relating to the first location wherein one of the plurality of transforms is selected for transforming third party location estimate data based on a first known determinable characteristic other than the RF fingerprint data and the third party location estimates.

18. A method according to claim 17 wherein the first known determinable characteristic is the time of day.

19. A method according to claim 17 wherein the first known determinable characteristic is building material.

20. A method according to claim 1 wherein the transform is a function of location estimates based on the RF fingerprint data.

21. A method according to claim 1 wherein the transform is a function of the third party location estimates.

22. A method according to claim 1 wherein the transform is a function of a wireless RF receiving device for sensing RF signals to determine the RF fingerprint data and for receiving the third party location estimates.