Location determination using historical data

• US 7,242,950 B2
• Filed: 02/18/2003
• Issued: 07/10/2007
• Est. Priority Date: 02/18/2003
• Status: Expired due to Term

• Current Assignee: SBC Properties, L.P. (AT&T, Inc.)
• Original Assignee: SBC Properties, L.P. (AT&T, Inc.)
• Inventors: Suryanarayana, Lalitha, Patron, David
• Primary Examiner(s): Nguyen, Duc M.
• Assistant Examiner(s): Huynh, Chuck
• Application Number:
  US10/369,147
• Publication Number:
  US 20040162090A1
• Time in Patent Office: 1,603 Days
• Field of Search: 455/456.1, 455/456.5, 455/422, 455/450, 455/456, 455/41.2, 455/457, 455/412.1, 455/412.2, 455/550.1, 370/329, 370/401, 370/338, 709/223, 709/224
• US Class Current: 455/456.5
• CPC Class Codes: G01S 5/0269 Inferred or constrained positioning, e.g. employing knowledge of the physical or electromagnetic environment, state of motion or other contextual information to infer or constrain a position
• CPC Class Codes: G01S 5/0295 Proximity-based methods, e.g. position inferred from reception of particular signals
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A plurality of wireless network access points (NAPs) each having a known location are provided. The wireless NAPs comprise shorter-range NAPs and longer-range NAPs. An associated precedence is assigned to each of the NAPs. A history database is to track a sequence of the NAPs accessed by a wireless device in a session. If a request for information from the wireless device is received by at least two of the NAPs, a processor determines which of the at least two NAPs has a greatest precedence and assigns same as a current NAP. The processor estimates a current location of the wireless device based on the known location of the current NAP and the known location of a previously-current NAP for the wireless device from the history database.

Claims

1. A system comprising:

a history database to track a sequence of wireless network access points (NAPs) accessed by a wireless device in a session, the NAPs part of a plurality of NAPs each having a known location and a unique identifier, the plurality of NAPs comprising a plurality of shorter-range NAPs and a plurality of longer-range NAPs, each NAP comprising an associated precedence; and

a location determination component to determine which of at least two NAPs that receive a request for information from the wireless device has a greatest precedence and to assign same as a current NAP, to determine whether the current NAP is a NAP of the plurality of shorter-range NAPs or the plurality of longer-range NAPs, to determine whether a previously-current NAP for the wireless device from the history database is within the range of the current NAP, and to estimate a current location of the wireless device based on the known location of the current NAP and the known location of the previously-current NAP for the wireless device from the history database;

wherein the estimate of the current location is biased towards the previously-current NAP when the current NAP is one of the plurality of longer-range NAPs and the previously-current NAP is located outside the range of the current NAP; and

wherein the estimate of the current location is within the range of the current NAP and not within the range of the previously-current NAP when the current NAP is one of the plurality of longer-range NAPs and the previously-current NAP is located within the range of the current NAP.

2. The system of claim 1 wherein each of the shorter-range NAPs located within a range of one of the longer-range NAPs is assigned a higher precedence than the one of the longer-range NAPs.

3. The system of claim 1 wherein each shorter-range NAP has a higher precedence than each longer-range NAP.

4. The system of claim 1 wherein the location determination component is to estimate the current location based on topological information of locations where the wireless device may not be located.

5. The system of claim 1 wherein the location determination component is to update the history database to record the current NAP.

6. The system of claim 1 wherein the location determination component is to update the history database to record the current location.

7. The system of claim 1 wherein the location determination component is to update the history database to record a time stamp.

8. The system of claim 1 wherein the location determination component is to update the history database to record NAP-to-NAP transition information.

9. The system of claim 1 wherein the longer-range NAPs comprise a plurality of 802.11 NAPs.

10. The system of claim 9 wherein the shorter-range NAPs are wireless communication NAPs operating in an unlicensed ISM band at 2.4 GHz.

11. The system of claim 1 further comprising a content server component to retrieve information associated with the current location, and to communicate the information to the wireless device in response to the request for information.

12. A method comprising:

receiving, by at least one of a plurality of wireless network access points (NAPs), a request for information from a wireless device, the plurality of NAPs comprising a plurality of shorter-range NAPs and a plurality of longer-range NAPs;

determining whether the request is received by one of the shorter-range NAPs;

in response to determining the request is received by one of the shorter-range NAPs;

assigning the shorter-range NAP receiving the request as a current NAP; and

estimating a current location of the wireless device based on a location of the current NAP;

wherein the current location of the wireless device is estimated based on a location of the current NAP and a last-estimated location of the wireless device when a history database includes previous location data for the wireless device in the session;

in response to determining the request is not received by any of the shorter-range NAPs;

assigning the longer-range NAP receiving the request as the current NAP; and

estimating a current location of the wireless device based on a location of the current NAP;

wherein the estimate of the current location of the wireless device is within a range of the current NAP and biased toward a location of the current NAP when the history database includes previous location data for the wireless device in the session and a last request from the wireless device was received from one of the NAPs outside a range of the current NAP;

wherein the estimate of the current location of the wireless device is within a range of the current NAP and not within a range a NAP receiving a last request from the wireless device when the history database includes previous location data for the wireless device in the session and a last request from the wireless device was received from a NAP within a range of the current NAP;

updating the history database to record the current location of the wireless device;

wherein the history database tracks locations of the wireless device in a session.

13. The method of claim 12 wherein the longer-range NAPs comprise a plurality of 802.11 NAPs.

14. The method of claim 12 wherein the shorter-range NAPs are wireless communication NAPs operating in an unlicensed ISM band at 2.4 GHz.

15. The method of claim 12 further comprising retrieving information associated with the current location and communicating the information to the wireless device in response to the request for information.

16. The method of claim 12 wherein to estimate the current location of the wireless device, the history database is queried to retrieve areas where other users have been most likely located at the current NAP and a location of highest likelihood within the range of the current NAP is determined based thereon when the history database is absent previous location data for the wireless device in the session.