LOCATION-BASED SERVICES THAT CHOOSE LOCATION ALGORITHMS BASED ON NUMBER OF DETECTED WIRELESS SIGNAL STATIONS WITHIN RANGE OF USER DEVICE

• US 20080139217A1
• Filed: 12/04/2007
• Published: 06/12/2008
• 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: Alizadeh-Shabdiz, Farshid, Jones, Russel K., Shean, Michael G., Morgan, Edward J.
• Granted Patent: US 7,818,017 B2
• Time in Patent Office: Days
• US Class Current: 455/456.1
• CPC Class Codes: G01S 19/13 Receivers
• CPC Class Codes: G01S 19/14 specially adapted for specific applications
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 5/0205 Details
• CPC Class Codes: G01S 5/021 Calibration, monitoring or correction G01S5/0252 takes precedence
• 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 5/02526 using non-dedicated equipment, e.g. user equipment or crowd-sourcing
• CPC Class Codes: G01S 5/0284 Relative positioning
• CPC Class Codes: G06Q 10/0875 Itemisation or classification of parts, supplies or services, e.g. bill of materials
• CPC Class Codes: G08G 1/20 Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• 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 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• 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 88/06 : adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/08 : Access point devices
• CPC Class Codes: Y10S 707/99936 : Pattern matching access

Abstract

A location beacon database and server, method of building location beacon database, and location based service using same. Wi-Fi access points are located in a target geographical area to build a reference database of locations of Wi-Fi access points. At least one vehicle is deployed including at least one scanning device having a GPS device and a Wi-Fi radio device and including a Wi-Fi antenna system. The target area is traversed in a programmatic route to avoid arterial bias. The programmatic route includes substantially all drivable streets in the target geographical area and solves an Eulerian cycle problem of a graph represented by said drivable streets. While traversing the target area, periodically receive the GPS coordinates of the GPS device. While traversing the target area, detecting Wi-Fi signals from Wi-Fi access points in range of the Wi-Fi device and recording identity information of the detected Wi-Fi access point in conjunction with GPS location information of the vehicle when the detection of the Wi-Fi access point was made. The location information is used to reverse triangulate the position of the detected Wi-Fi access point; and the position of the detected access point is recorded in a reference database.

Claims

1. A method of locating a user-device having a wireless signal receiver, comprising:

providing a reference database of locations of wireless signal stations in a target area;

receiving messages transmitted by the wireless signal stations within range of the wireless signal receiver, each message identifying the wireless signal station sending the message;

calculating the signal strength of the messages received by the wireless signal receiver;

accessing the reference database to obtain the locations for the identified wireless signal stations;

based on the number of wireless signal stations identified via received messages, choosing a corresponding location-determination algorithm from a plurality of location-determination algorithms, said chosen algorithm being suited for the number of identified wireless signal stations; and

using the locations for the identified wireless signal stations and the signal strengths of said received messages and the chosen location-determination algorithm to determine the location of the user-device.

2. The method of claim 1 wherein the wireless signal stations are terrestrially based.

3. The method of claim 2 wherein the wireless signal stations are for transmitting wireless signals to and receiving wireless signals transmitted from a plurality of terrestrially based wireless radio devices.

4. The method of claim 1 wherein the locations for the identified wireless signal stations are filtered to determine if the corresponding wireless signal stations have moved since the time the information about the wireless signal stations was included in the reference database.

5. The method of claim 1 wherein the reference database is located locally relative to the user-device.

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

7. The method of claim 1 wherein the location of the user device is provided with latitude and longitude coordinates.

8. The method of claim 1 wherein the plurality of location-determination algorithms includes a simple signal strength weighted average model.

9. The method of claim 1 wherein the plurality of location-determination algorithms includes a nearest neighbor model.

10. The method of claim 1 wherein the plurality of location-determination algorithms includes a triangulation technique.

11. The method of claim 1 wherein the plurality of location-determination algorithms includes an adaptive smoothing technique based on the device velocity.

12. The method of claim 1 wherein the choice of location-determination algorithm is further based on the user application making the location request.

13. The method of claim 1 wherein reference database of locations further includes signal fingerprint information of at least one of the wireless signal stations, the signal fingerprint information including a plurality of expected signal strength readings of messages transmitted by the wireless signal station at a corresponding plurality of expected locations where the messages are received.

14. The method of claim 13 wherein the plurality of location-determination algorithms includes a technique based on signal fingerprint information for more than one wireless signal station.

15. The method of claim 14 wherein the technique includes determining a location by:

calculating the signal strength of messages received by the wireless signal receiver;

comparing the calculated signal strength with the expected signal strengths of the signal fingerprint information for the more than one wireless signal station to find expected signal strengths that most closely match the calculated signal strength; and

determining the location of the user-device based on expected locations that correspond to the expected signal strengths most closely matching the calculated signal strength.

16. The method of claim 1 wherein more than one location-determination algorithm from the plurality of location-determination algorithms is used to determine the location of the user-device.

17. A method of locating a user-device having a wireless signal receiver, comprising:

providing a reference database of wireless signal station information about wireless signal stations in a target area;

in response to a user application request to determine a location of a user-device having a wireless signal receiver, receiving messages from wireless signal stations within range of the wireless signal receiver, each message identifying the wireless signal station sending the message;

determining attributes of the messages received by the wireless signal receiver;

accessing the reference database to obtain information about the identified wireless signal stations;

based on the number of wireless signal stations identified via received messages, choosing a corresponding location-determination algorithm from a plurality of location-determination algorithms, said chosen algorithm being suited for the number of identified wireless signal stations; and

using the information about the identified wireless signal stations and the determined attributes of said received messages and the chosen location-determination algorithm to determine the location of the user-device.

18. The method of claim 17, wherein a first location-determination algorithm of the plurality of location-determination algorithms uses a first set of information about the identified wireless signal stations and a second location-determination algorithm of the plurality of location-determination algorithms uses a second set of information about the identified wireless signal stations, the first set of information differing from the second set of information.