Continuous Data Optimization of Moved Access Points in Positioning Systems

• US 20120309420A1
• Filed: 08/13/2012
• Published: 12/06/2012
• 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 J., Shean, Michael G., Alizadeh-Shabdiz, Farshid, Jones, Russel K.
• Granted Patent: US 8,478,297 B2
• Time in Patent Office: Days
• US Class Current: 455/456.1
• 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 detecting WiFi access points that identifies and distinguishes between (a) WiFi access points that seem to have reliable associated location information that can be used in estimating the position of a mobile WiFi-enabled device and (b) WiFi access points that seem to have moved substantially relative to recorded location information associated with the WiFi access points such that their true location is not reliably known and their associated location information should not be used in estimating the position of the mobile WiFi-enabled device, the method comprising:

a mobile WiFi-enabled device receiving signals from WiFi access points within range of the mobile WiFi-enabled device so that a plurality of WiFi access points identify themselves;

in response to identifying the plurality of WiFi access points, at least one of the mobile WiFi-enabled device and a server in communication with the mobile WiFi-enabled device accessing a reference database system to obtain location information associated with each of the identified WiFi access points, said location information specifying a previously-determined approximate location of the associated WiFi access point;

at least one of the mobile WiFi-enabled device and the server in communication with the mobile WiFi-enabled device comparing the location information associated with each identified WiFi access point to the location information associated with other WiFi access points of the plurality to identify any WiFi access points that are suspected to have moved substantially from their specified location such that their true location is not reliably known at present nor reliably specified in the associated location information, said identifying determining that the specified location of the suspect WiFi access point is too extreme in distance relative to specified locations associated with other identified WiFi access points relative to a typical signal range of WiFi access points to infer that the specified location associated with the suspect WiFi access point does not reliably reflect the true location of the suspect WiFi access point and that the suspect WiFi access point must have moved substantially from its specified location to a presently unknown true location; and

at least one of the mobile WiFi-enabled device and the server in communication with the mobile WiFi-enabled device indicating in the reference database system as unreliable for position determination any of the WiFi access points that are suspected to have moved to a presently unknown true position thereby indicating that the location information associated with the unreliable WiFi access points should not be used in estimating the position of the mobile WiFi-enabled device.