Locating a mobile device

• US 9,588,217 B2
• Filed: 01/29/2016
• Issued: 03/07/2017
• Est. Priority Date: 03/27/2012
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Un, Edward Ding-Bong, Zhao, Jun, Wang, Kai, Mu, Hailong, Xu, Zeyong
• Primary Examiner(s): Batista, Marcos
• Application Number:
  US15/011,086
• Publication Number:
  US 20160334495A1
• Time in Patent Office: 403 Days
• Field of Search: 4554561-4563, 370/338
• US Class Current: 1/1
• CPC Class Codes: G01S 5/02521 using a radio-map
• CPC Class Codes: G01S 5/0278 involving statistical or probabilistic considerations G01S5/0252, G01S5/0294 take precedence
• 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

Abstract

Identifying a location of a mobile device is disclosed (e.g., presuming user consent to the same). One or more received signal strengths (RSSs), comprising a first RSS, may be received by a first access point (AP) from the mobile device. The RSSs may be used to identify a grid area, comprising a first grid space. A signal distance between the first grid space and the first AP may be identified using the first RSS, and combined with a first grid space distance, comprising a known distance between the first grid space and the first AP, to determine a first grid space likelihood score for the first grid space. A second grid space likelihood score may be determined for a second grid space (e.g., and a third, etc.), and the grid space comprising a desired grid space likelihood score (e.g., highest) may be selected as the mobile device location.

Claims

1. A computer based method for identifying a location of a mobile device, comprising:

receiving a plurality of mobile device signal reports from a plurality of access points (AP);

filtering one or more reports, associated with unknown access points from the received mobile device signal reports;

indexing the filtered mobile device signal reports;

receiving a query from an application associated with the mobile device to identify the location of the mobile device;

retrieving data from the indexed filtered mobile device signal reports based on the query;

identifying a candidate area comprising the location of the mobile device using the retrieved data;

creating grid data for a plurality of grid spaces in the identified candidate area;

determining a grid space likelihood score for each of the plurality of grid spaces based on the grid data and the query; and

identifying the location of the mobile device based on the determined grid space likelihood scores, at least a portion of the method implemented at least in part via a processing unit.

2. A computer based method for identifying a location of a mobile device, comprising:

determining a first signal distance between a first grid space and a first access point (AP) using a first received signal strength (RSS), the first RSS comprising an indication of mobile device signal strength received by the first AP;

determining a first expected distance between the first AP and a second AP using a first AP RSS, the first AP RSS comprising an indication of signal strength for a signal transmitted from the second AP and received by the first AP;

determining a first AP difference based at least on a combination of the first expected distance and a first known AP distance, the first known AP distance comprising a known distance between the first AP and the second AP;

determining a first grid space likelihood score based on the first signal distance, the first AP difference, and a first grid space distance, the first grid space distance comprising a known distance between the first AP and the first grid space; and

identifying the location of the mobile device based at least on the first grid space likelihood score, at least a portion of the method implemented at least in part via a processing unit.

3. A computer based method for identifying a location of a mobile device, comprising:

identifying a candidate area comprising the location of the mobile device, the candidate area comprising a plurality of access points;

creating a plurality of grid spaces in the identified candidate area;

determining a grid space likelihood score for each of the plurality of grid spaces based on a signal distance and a grid space distance between each grid space and each of the plurality of access points, the grid space distance representing a known distance between an access point and a grid space, the signal distance representing an estimated distance between a grid space and an access point using a received signal strength (RSS), the RSS comprising an indication of mobile device signal strength received by the AP if the mobile device was located in the grid space; and

identifying the location of the mobile device as a grid space having highest grid space likelihood score, at least a portion of the method implemented at least in part via a processing unit.