Continuous data optimization of moved access points in positioning systems

• US 9,398,558 B2
• Filed: 09/13/2013
• Issued: 07/19/2016
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: Skyhook Wireless Incorporated (Liberty Broadband Corp.)
• Original Assignee: Skyhook Wireless Incorporated (Liberty Broadband Corp.)
• Inventors: Morgan, Edward James, Shean, Michael George, Alizadeh-Shabdiz, Farshid, Jones, Russel Kipp
• Primary Examiner(s): Daniel, Jr., Willie J
• Application Number:
  US14/026,070
• Publication Number:
  US 20140080510A1
• Time in Patent Office: 1,040 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G01S 5/0205 Details
• CPC Class Codes: H04W 12/122 Counter-measures against attacks; Protection against rogue devices
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 4/20 Services signaling; Auxiliary data signalling, i.e. transmitting data via a non-traffic channel
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 64/003 locating network equipment
• CPC Class Codes: H04W 84/10 Small scale networks; Flat hierarchical networks
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Methods and systems of continuously optimizing data in WiFi positioning systems. A location-based services system uses WiFi-enabled devices to monitor WiFi access points in a target area to indicate whether a WiFi access point has moved relative to its previously recorded location. A WiFi-enabled device communicates with WiFi access points within range of the WiFi-enabled device so that observed WiFi access points identify themselves; A reference database is accessed to obtain information specifying a recorded location for each observed WiFi access point in the target area. The recorded location information is used for each of the observed WiFi access points in conjunction with predefined rules to infer whether an observed WiFi access point has moved relative to its recorded location. The reference database is informed of the identity of any observed WiFi access point that is inferred to have moved.

Claims

1. A method of identifying a WiFi access point that is suspected to have moved relative to location information associated with the WiFi access point which is recorded in a reference database, the method comprising:

at least one of a mobile WiFi-enabled device and a server system in communication with the mobile WiFi-enabled device receiving information identifying a WiFi access point in range of the mobile WiFi-enabled device;

at least one of the mobile WiFi-enabled device and the server system in communication with the mobile WiFi-enabled device accessing a reference database to retrieve location information that is associated with the identified WiFi access point recorded in the reference database, the location information specifying a previously-determined location of the identified WiFi access point;

at least one of the mobile WiFi-enabled device and the server system in communication with the mobile WiFi-enabled device determining a location estimate of the mobile WiFi-enabled device;

at least one of the mobile WiFi-enabled device and the server system in communication with the mobile WiFi-enabled device comparing the location estimate of the mobile WiFi-enabled device to the recorded location information associated with the identified WiFi access point to infer whether the identified WiFi access point has moved from its previously-determined location that is recorded in the reference database; and

in response to inferring that the identified WiFi access point has moved from its previously-determined location that is recorded in the reference database, at least one of the mobile WiFi-enabled device and the server system in communication with the mobile WiFi-enabled device updating the location information that is associated with the identified WiFi access point recorded in the reference database and associating a quality attribute with the updated location.

2. The method of claim 1, wherein an initial value of the quality attribute for the updated location information indicates a level of confidence in the updated location information that is less than a level of confidence associated with updated location information that is validated by multiple mobile WiFi-enabled devices.

3. The method of claim 1, wherein the inferring includes determining whether the recorded location information associated with the identified WiFi access point is more than a threshold distance from the location estimate of the mobile WiFi-enabled device.

4. The method of claim 3, wherein the determination of the location estimate of the mobile WiFi-enabled device is based on signals received from a number of WiFi access points, and where the threshold distance varies based on the number of WiFi access points used to determine the location estimate for the mobile WiFi-enabled device.

5. The method of claim 1, wherein the at least one location estimate of the mobile WiFi-enabled device is retrieved from the server system.

6. The method of claim 1, wherein the reference database is located remotely relative to the WiFi-enabled device.

7. The method of claim 1, wherein the reference database is located on the mobile WiFi-enabled device.

8. The method of claim 1, wherein the updating the location information that is associated with the identified WiFi access point recorded in the reference database includes estimating a geographic position of the identified WiFi access point.

9. The method of claim 8, wherein the estimating the geographic position of the identified WiFi access point that is inferred to have moved from its previously-determined location is based at least in part on location information associated with WiFi access points other than WiFi access points that are inferred to have moved from their corresponding previously-determined locations.

10. The method of claim 1, further comprising altering the quality attribute associated with the updated location information of the identified WiFi access point in response to receiving validation from one or more other mobile WiFi-enabled devices of the updated location information of the identified WiFi access point.

11. The method of claim 10, wherein the alteration of the quality attribute reflects an increased level of confidence in the updated location information associated with the identified WiFi access point.

12. A mobile WiFi-enabled device comprising:

a WiFi radio; and

a storage device storing Wi-Fi positioning system (WPS) client software that includes;

a scanner configured to use the Wi-Fi radio to identify a Wi-Fi access point within range of the mobile WiFi-enabled device,

a locator configured to search for and retrieve location information that is associated with the identified WiFi access point from a local copy of a reference database on the mobile WiFi-enabled device or a remote reference database on a server system, the location information specifying a previously-determined location of the identified WiFi access point,

a location calculation component configured to determine a location estimate of the mobile WiFi-enabled device, and

a quality filter configured to compare the location estimate of the mobile WiFi-enabled device to the recorded location information associated with the identified WiFi access point to infer whether the identified WiFi access point has moved from its previously-determined location, and to generate in response to inferring that the identified WiFi access point has moved from its previously-determined location feedback, wherein the feedback is usable to update the location information that is associated with the identified WiFi access point.

13. The mobile WiFi-enabled device of claim 12, wherein the locator is configured to search for and retrieve location information that is associated with the identified WiFi access point from the local copy of the reference database on the mobile WiFi-enabled device, and the feedback is one or more feedback files that are stored locally and then transmitted to the server system over a network connection.

14. The mobile WiFi-enabled device of claim 12, wherein the locator is configured to search for and retrieve location information that is associated with the identified WiFi access point from the reference database on the server system, and the feedback is sent substantially in real-time to the server system over a network connection.

15. The mobile WiFi-enabled device of claim 12, wherein the inference whether the identified WiFi access point has moved from its previously-determined location is based on whether the location information for the WiFi access point recorded in the reference database indicates a location that is more than a threshold distance away from the location estimate of the mobile WiFi-enabled device.

16. The mobile WiFi-enabled device of claim 12, wherein the feedback is further usable to update a quality attribute associated with the identified WiFi access point in the reference database on the server system, where the quality attribute indicates a level of confidence in the updated location.

17. The mobile WiFi-enabled device of claim 16, wherein the level of confidence indicated by an initial value of the quality attribute is less than a level of confidence associated with an updated location that is validated by multiple mobile WiFi-enabled devices.

18. A non-transitory computer readable medium having instructions stored thereon, the instructions when executed on a server system being operable to:

receive feedback from a mobile WiFi-enabled device that has identified a WiFi access point to be within range of a WiFi radio of the mobile WiFi-enabled device, the feedback from the mobile WiFi-enabled device indicating that a location of the WiFi access point recorded in a reference database is more than a threshold distance away from a location estimate of the mobile WiFi-enabled device; and

in response to the feedback from the mobile WiFi-enabled device,

updating the location of the Wi-Fi access point recorded in the reference database based at least in part on locations of one or more other Wi-Fi access points identified to be within range of the WiFi radio of the mobile WiFi-enabled device, and

associating the updated location of the Wi-Fi access point with a quality attribute, wherein the quality attribute indicates a level of confidence in the updated location.

19. The non-transitory computer readable medium of claim 18, wherein the level of confidence indicated by an initial value of the quality attribute is less than a level of confidence associated with an updated location that is validated by multiple mobile WiFi-enabled devices.

20. The non-transitory computer readable medium of claim 18, wherein the feedback is one or more feedback files that are received over a network connection.