Systems and methods for using a satellite positioning system to detect moved WLAN access points

• US 8,564,481 B2
• Filed: 07/17/2012
• Issued: 10/22/2013
• Est. Priority Date: 07/16/2009
• Status: Active Grant

• Current Assignee: Skyhook Wireless Incorporated (Liberty Broadband Corp.)
• Original Assignee: Skyhook Wireless Incorporated (Liberty Broadband Corp.)
• Inventors: Alizadeh-Shabdiz, Farshid
• Primary Examiner(s): LIU, HARRY K
• Application Number:
  US13/551,305
• Publication Number:
  US 20120280866A1
• Time in Patent Office: 462 Days
• Field of Search: 342/463
• US Class Current: 342/463
• CPC Class Codes: G01S 19/00 Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 5/0226 Transmitters
• CPC Class Codes: G01S 5/0242 Determining the position of transmitters to be subsequently used in positioning G01S5/0289 takes precedence
• CPC Class Codes: G01S 5/0263 by combining or switching between positions derived from two or more separate positioning systems
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services

Abstract

The disclosed subject matter generally relates to hybrid positioning systems and methods and, more specifically, systems and methods of detecting moved WLAN assess points using a wireless local area network based positioning system (WLAN-PS) and a satellite-based positioning system (SPS) with at least two satellites measurement.

Claims

1. A method of using information from a Wireless Local Area Network (WLAN) and satellite enabled device to confirm that a reference location associated with a detected WLAN access point (AP) is the present location of the AP, the method comprising:

identifying at least one WLAN AP detected by the WLAN and satellite enabled device;

accessing a reference database to obtain a reference location associated with the at least one WLAN AP;

receiving a position estimate for the device from at least one of a WLAN positioning system (WLAN PS), a satellite positioning system (SPS), or a hybrid positioning system, wherein the hybrid positioning system generates the position estimate based on signals from at least one WLAN AP and at least one satellite;

estimating a distance between the reference location associated with the WLAN AP and the position estimate of the device; and

confirming that the reference location associated with the WLAN AP is the present location of the WLAN AP based on the distance between the reference location associated with the WLAN AP and the position estimate of the device.

2. The method of claim 1, further comprising indicating in the reference database that the reference location associated with the WLAN AP is confirmed to be the present location of the WLAN AP.

3. The method of claim 2, wherein the indicating comprises assigning a binary value.

4. The method of claim 2, wherein the indicating comprises assigning a non-binary value.

5. The method of claim 1, wherein the confirming of the reference location associated with the WLAN AP is determined at least in part by a measure of consistency between one or more computed WLAN-based positions and satellite-based positions.

6. The method of claim 1, wherein the confirming of the reference location associated with the WLAN AP is determined at least in part by error estimates associated with one or more computed WLAN-based positions and satellite-based positions.

7. The method of claim 1, wherein the confirming that the reference location associated with the WLAN AP is the present location of the WLAN AP is based on the distance between the reference location associated with the WLAN AP and the position estimate of the device not exceeding a predetermined threshold.

8. The method of claim 7, wherein the predetermined threshold is based on an estimated coverage area of the WLAN AP.

9. A system for using information from a Wireless Local Area Network (WLAN) and satellite enabled device to confirm that a reference location associated with a detected WLAN access point (AP) is the present location of the AP, the system comprising:

logic for identifying at least one WLAN AP detected by the WLAN and satellite enabled device;

logic for accessing a reference database to obtain a reference location associated with the at least one WLAN AP and a quality measurement associated with the reference location;

logic for providing a position estimate for the device from at least one of a WLAN positioning system (WLAN PS), a satellite positioning system (SPS), or a hybrid positioning system, said hybrid positioning system including logic for determining the position estimate by combining a position estimate for the device from the SPS and a position estimate for the device from the WLAN PS;

logic for estimating a distance between the reference location associated with the WLAN AP and the position estimate of the device; and

logic for confirming that the reference location associated with the WLAN AP is the present location of the WLAN AP based on (i) the distance between the reference location associated with the WLAN AP and the position estimate of the device and (ii) the quality measurement associated with the reference location.

10. The system of claim 9, further comprising logic for indicating in the reference database that the reference location associated with the WLAN AP is confirmed to be the present location of the WLAN AP.

11. The system of claim 10, wherein the indicating comprises assigning a binary value.

12. The system of claim 10, wherein the indicating comprises assigning a non-binary value.

13. The system of claim 9, wherein the confirming of the reference location associated with the WLAN AP is determined at least in part by a measure of consistency between one or more computed WLAN-based positions and satellite-based positions.

14. The system of claim 9, wherein the confirming of the reference location associated with the WLAN AP is determined at least in part by error estimates associated with one or more computed WLAN-based positions and satellite-based positions.

15. The system of claim 9, wherein the confirming that the reference location associated with the WLAN AP is the present location of the WLAN AP is based on the distance between the reference location associated with the WLAN AP and the position estimate of the device not exceeding a predetermined threshold.

16. The system of claim 15, wherein the predetermined threshold is based on an estimated coverage area of the WLAN AP.