Positioning with wireless local area networks and WLAN-aided global positioning systems

• US 8,909,252 B2
• Filed: 11/01/2013
• Issued: 12/09/2014
• Est. Priority Date: 02/14/2003
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Wang, Yi-Hsiu
• Primary Examiner(s): LE, DANH C
• Application Number:
  US14/070,431
• Publication Number:
  US 20140057653A1
• Time in Patent Office: 403 Days
• Field of Search: 455/456.1, 455/456.5, 455/522, 455/456.6
• US Class Current: 455/456.1
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/06 employing an initial estimate of the location of the receiver as aiding data or in generating aiding data
• CPC Class Codes: G01S 19/252 Employing an initial estimate of location in generating assistance data
• CPC Class Codes: G01S 19/28 Satellite selection
• CPC Class Codes: G01S 19/29 carrier including Doppler, related G01S19/246 takes precedence
• CPC Class Codes: G01S 19/48 by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H04B 7/1851 Systems using a satellite or space-based relay H04B7/18508, H04B7/18521 take precedence; providing specific services H04B7/18523 - H04B7/18576
• CPC Class Codes: H04W 4/02 Services making use of location 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 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Accurate position capability can be quickly provided using a Wireless Local Area Network (WLAN). When associated with a WLAN, a wireless device can quickly determine its relative and/or coordinate position based on information provided by an access point in the WLAN. Before a wireless device disassociates with the access point, the WLAN can periodically provide time, location, and decoded GPS data to the wireless device. In this manner, the wireless device can significantly reduce the time to acquire the necessary GPS satellite data (i.e. on the order of seconds instead of minutes) to determine its coordinate position.

Claims

1. A method of determining a location of a wireless device, the method including:

determining a first access point (AP) having a first known location, a second AP having a second known location, and a third AP having a third known location;

determining a first radio signal strength indicator (RSSI) of the first AP, a second RSSI of the second AP, and a third RSSI of the third AP;

determining weighting factors using values associated with the first RSSI, the second RSSI, and the third RSSI; and

determining a coordinate location of the wireless device using the first known location, the second known location, the third known location, and the weighting factors.

2. The method of claim 1, wherein the values associated with the first RSSI, the second RSSI, and the third RSSI include relative distances from the first AP, the second AP, and the third AP to the wireless device.

3. The method of claim 1, wherein said determining weighting factors includes:

determining a first relative distance from the first AP to the wireless device based on the first RSSI, a second relative distance from the second AP to the wireless device based on the second RSSI, and a third relative distance from the third AP to the wireless device based on the third RSSI,

wherein the values include the first relative distance, the second relative distance, and the third relative distance.

4. The method of claim 1, further including:

correlating the first RSSI to a first distance, wherein the first distance represents a first relative distance from the first AP to the wireless device;

correlating the second RSSI to a second distance, wherein the second distance represents a second relative distance from the second access point to the wireless device; and

correlating the third RSSI to a third distance, wherein the third distance represents a third relative distance from the third access point to the wireless device,

wherein the values associated with the first RSSI, the second RSSI, and the third RSSI include the first distance, the second distance, and the third distance.

5. The method of claim 1, wherein said determining the first AP having the first known location, the second AP having the first known location, and the third AP having the third known location, and said determining the first RSSI of the first AP, the second RSSI of the second AP, and the third RSSI of the third AP are performed by the wireless device, and wherein and said determining weighting factors using the values associated with the first RSSI, the second RSSI, and the third RSSI, and said determining the coordinate location of the wireless device using the first known location, the second known location, the third known location, and the weighting factors are performed by a server.

6. The method of claim 1, wherein said determining the first AP having the first known location, the second AP having the first known location, and the third AP having the third known location, said determining the first RSSI of the first AP, the second RSSI of the second AP, and the third RSSI of the third AP, and said determining weighting factors using the values associated with the first RSSI, the second RSSI, and the third RSSI are performed by the wireless device, and wherein said determining the coordinate location of the wireless device using the first known location, the second known location, the third known location, and the weighting factors is performed by a server.

7. A wireless device for operating in a wireless system, the wireless system including a plurality of access points, the wireless device to perform a location technique comprising:

determining a first access point (AP) having a first known location, a second AP having a second known location, and a third AP having a third known location;

determining a first radio signal strength indicator (RSSI) of the first AP, a second RSSI of the second AP, and a third RSSI of the third AP;

determining weighting factors using values associated with the first RSSI, the second RSSI, and the third RSSI; and

determining a coordinate location of the wireless device using the first known location, the second known location, the third known location, and the weighting factors.

8. The wireless device of claim 7, wherein the values associated with the first RSSI, the second RSSI, and the third RSSI include relative distances from the first AP, the second AP, and the third AP to the wireless device.

9. The wireless device of claim 7, wherein said determining weighting factors includes:

determining a first relative distance from the first AP to the wireless device based on the first RSSI, a second relative distance from the second AP to the wireless device based on the second RSSI, and a third relative distance from the third AP to the wireless device based on the third RSSI,

wherein the values include the first relative distance, the second relative distance, and the third relative distance.

10. The wireless device of claim 7, further including:

correlating the first RSSI to a first distance, wherein the first distance represents a first relative distance from the first AP to the wireless device;

correlating the second RSSI to a second distance, wherein the second distance represents a second relative distance from the second access point to the wireless device; and

correlating the third RSSI to a third distance, wherein the third distance represents a third relative distance from the third access point to the wireless device,

wherein the values include the first distance, the second distance, and the third distance.

11. A wireless device for operating in a wireless system, the wireless system including a plurality of access points, the wireless device to perform a location technique comprising:

means for determining a first access point (AP) having a first known location, a second AP having a second known location, and a third AP having a third known location;

means for determining a first radio signal strength indicator (RSSI) of the first AP, a second RSSI of the second AP, and a third RSSI of the third AP;

means for determining weighting factors using values associated with the first RSSI, the second RSSI, and the third RSSI; and

means for determining a coordinate location of the wireless device using the first known location, the second known location, the third known location, and the weighting factors.

12. The wireless device of claim 11, wherein the values associated with the first RSSI, the second RSSI, and the third RSSI include relative distances from the first AP, the second AP, and the third AP to the wireless device.

13. The wireless device of claim 11, wherein said means for determining weighting factors includes:

means for determining a first relative distance from the first AP to the wireless device based on the first RSSI, a second relative distance from the second AP to the wireless device based on the second RSSI, and a third relative distance from the third AP to the wireless device based on the third RSSI,

wherein the values include the first relative distance, the second relative distance, and the third relative distance.

14. The wireless device of claim 11, further including:

means for correlating the first RSSI to a first distance, wherein the first distance represents a first relative distance from the first AP to the wireless device;

means for correlating the second RSSI to a second distance, wherein the second distance represents a second relative distance from the second access point to the wireless device; and

means for correlating the third RSSI to a third distance, wherein the third distance represents a third relative distance from the third access point to the wireless device,

wherein the values include the first distance, the second distance, and the third distance.

15. A system including a plurality of access points, a wireless device, and a server, the wireless device and the server to perform a location technique comprising:

using the wireless device configured to perform steps including;

determining a first access point (AP) having a first known location, a second AP having a second known location, and a third AP having a third known location;

determining a first radio signal strength indicator (RSSI) of the first AP, a second RSSI of the second AP, and a third RSSI of the third AP;

determining weighting factors using values associated with the first RSSI, the second RSSI, and the third RSSI;

using the server configured to perform steps including;

determining a coordinate location of the wireless device using the first known location, the second known location, the third known location, and the weighting factors; and

sending the coordinate location to the wireless device.

16. The system of claim 15, wherein the values associated with the first RSSI, the second RSSI, and the third RSSI include relative distances from the first AP, the second AP, and the third AP to the wireless device.

17. The system of claim 15, wherein said determining weighting factors includes:

determining a first relative distance from the first AP to the wireless device based on the first RSSI, a second relative distance from the second AP to the wireless device based on the second RSSI, and a third relative distance from the third AP to the wireless device based on the third RSSI,

wherein the values include the first relative distance, the second relative distance, and the third relative distance.

18. The system of claim 15, wherein the wireless device is further configured to perform steps including:

correlating the first RSSI to a first distance, wherein the first distance represents a first relative distance from the first AP to the wireless device;

correlating the second RSSI to a second distance, wherein the second distance represents a second relative distance from the second access point to the wireless device; and

correlating the third RSSI to a third distance, wherein the third distance represents a third relative distance from the third access point to the wireless device,

wherein the values include the first distance, the second distance, and the third distance.

19. A system including a plurality of access points, a wireless device, and a server, the wireless device and the server to perform a location technique comprising:

using the wireless device configured to perform steps including;

determining a first access point (AP) having a first known location, a second AP having a second known location, and a third AP having a third known location;

determining a first radio signal strength indicator (RSSI) of the first AP, a second RSSI of the second AP, and a third RSSI of the third AP;

using the server configured to perform steps including;

determining weighting factors using values associated with the first RSSI, the second RSSI, and the third RSSI;

determining a coordinate location of the wireless device using the first known location, the second known location, the third known location, and the weighting factors; and

sending the coordinate location to the wireless device.

20. The system of claim 19, wherein the values associated with the first RSSI, the second RSSI, and the third RSSI include relative distances from the first AP, the second AP, and the third AP to the wireless device.

21. The system of claim 19, wherein said determining weighting factors includes:

determining a first relative distance from the first AP to the wireless device based on the first RSSI, a second relative distance from the second AP to the wireless device based on the second RSSI, and a third relative distance from the third AP to the wireless device based on the third RSSI,

wherein the values include the first relative distance, the second relative distance, and the third relative distance.

22. The system of claim 19, wherein the server is further configured to perform steps including:

correlating the first RSSI to a first distance, wherein the first distance represents a first relative distance from the first AP to the wireless device;

correlating the second RSSI to a second distance, wherein the second distance represents a second relative distance from the second access point to the wireless device; and

correlating the third RSSI to a third distance, wherein the third distance represents a third relative distance from the third access point to the wireless device,

wherein the values include the first distance, the second distance, and the third distance.