System and method for enabling continuous geographic location estimation for wireless computing devices

• US 7,397,424 B2
• Filed: 06/29/2005
• Issued: 07/08/2008
• Est. Priority Date: 02/03/2005
• Status: Active Grant

• Current Assignee: Skyhook Holding, Inc. (Liberty Broadband Corp.)
• Original Assignee: Mexens Intellectual Property Holding LLC
• Inventors: Houri, Cyril
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): LIU, HARRY K
• Application Number:
  US11/170,337
• Publication Number:
  US 20060170591A1
• Time in Patent Office: 1,105 Days
• Field of Search: 342/357, 455/67, 701/200
• US Class Current: 342/357.31
• 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

Abstract

System and method for enabling a wireless computing device to continuously determine its position includes a wireless computing device and a wireless positioning system substantially collocated therewith. The wireless positioning system has a first positioning mode in which it communicates with a wireless positioning network to enable the geographic location of the computing device to be determined upon reception of signals from the positioning network and a second positioning mode in which it enables the geographic location of the wireless computing device to be determined upon reception of signals from one or more of the wireless beacons and analysis of the signals in light of positional information about wireless beacons contained in a database. The wireless positioning system switches between the positioning modes depending on reception of signals from the wireless positioning network.

Claims

1. A system for enabling a wireless computing device to determine its location both when communicating with one or more satellites of a wireless positioning network and when unable to communicate with any satellites of the wireless positioning network, comprising:

a wireless computing device; and

a wireless positioning system substantially collocated with said wireless computing device,

said wireless positioning system having a first positioning mode in which it communicates with the one or more satellites of the wireless positioning network to enable the geographic location of said wireless computing device to be determined upon reception of signals from only the one or more satellites of the wireless positioning network and a second positioning mode in which it enables the geographic location of said wireless computing device to be determined upon reception of signals from at least one non-satellite wireless beacon and analysis of the signals in light of positional information about wireless beacons contained in a database and said wireless positioning system being affanged to switch between said first and second positioning modes to obtain a determination of its geographic location depending on reception of signals from the one or more satellites of the wireless positioning network,

when in said first positioning mode and communicating with the one or more satellites of the wireless positioning network, said wireless computing device being arranged to

obtain its geographic location based on reception of signals only from the one or more satellites of the wireless positioning network and also

obtain identification and signal strength information about non-satellite wireless beacons and also

derive positional information about at least one of these wireless beacons, for which identification and signal strength information has been obtained but for which positional information is not present in said database, from both the obtained geographic location of said wireless computing device and the obtained identification and signal strength information about the non-satellite wireless beacons, the derived positional information then being included in said database, and

when in said second positioning mode and unable to communicate with the one or more satellites of the wireless positioning network, said wireless computing device being arranged to determine its geographic location based on reception of signals from at least one non-satellite wireless beacon whose positional information is included in said database and analysis of the signals in light of positional information about wireless beacons contained in said database and from which signals have been received.

2. The system of claim 1, wherein said wireless positioning system switches from said first positioning mode to said second positioning mode when signals from the wireless positioning network are not deemed sufficiently accurate or are unavailable, and from said second positioning mode to said first positioning mode when signals from the wireless positioning network are available and deemed accurate.

3. The system of claim 1, wherein said wireless positioning system is affanged in said wireless computing device.

4. The system of claim 1, wherein said wireless positioning system includes a software-implemented switch to switch between said first and second positioning modes.

5. The system of claim 1, wherein said wireless positioning system includes a GPS system which communicates with a satellite-based GPS positioning system to provide said first positioning mode.

6. The system of claim 1, wherein said wireless positioning system includes a calculation algorithm which determines the geographic location of said wireless computing device in said second positioning mode upon input of identification and signal strength information about the at least one wireless beacon derived from the received signals.

7. The system of claim 1, wherein said wireless computing device includes a scanner affanged to communicate with the one or more satellites of the wireless positioning network when said wireless computing device is in said first positioning mode to enable its geographic location to be determined upon reception of signals from only the one or more satellites of the wireless positioning network, said scanner being affanged to obtain positional information about itself and identification and signal strength information about non-satellite wireless beacons, whose positional information is not present in said database, in order to derive positional information about at least one such identified wireless beacon from the positional information about itself and the signal strength information to enable the derived positional information to be included in said database.

8. The system of claim 7, wherein said scanner is arranged to analyze strength of signals received from the wireless beacons at a plurality of different positions of said scanner and apply an algorithm to determine the positional information about the wireless beacons therefrom.

9. The system of claim 7, wherein said scanner is arranged to obtain identification and signal strength information about the wireless beacons, whose positional information is not present in said database, at a plurality of different locations and derive positional information for each identified wireless beacon from the signal strength information at the plurality of different locations.

10. The system of claim 1, wherein said database, which includes the derived positional information about the at least one wireless beacon, is arranged within said wireless computing device.

11. The system of claim 1, wherein said wireless computing device is a PDA or cell phone.

21. The system of claim 1, wherein said wireless positioning system includes a calculation algorithm which determines the geographic location of said wireless computing device in said second positioning mode upon input of identification and signal strength information received from a plurality of wireless beacons.

22. The system of claim 1, wherein said wireless computing device is arranged to derive positional information about the at least one wireless beacon, for which identification and signal strength information has been obtained but for which positional information is not present in said database, from the geographic location of said wireless computing device and identification and signal strength information obtained when said wireless computing device is at multiple and different locations.

23. The system of claim 1, wherein said wireless computing device is a Wi-Fi device.

26. The system of claim 1, wherein the at least one non-satellite wireless beacon is a fixed beacon.

27. The system of claim 1, wherein the at least one non-satellite wireless beacon is part of a network of beacons arranged to receive telecommunication signals addressed to a plurality of wireless computing devices and relay the telecommunication signals to another beacon or to a specific one of the wireless computing devices depending on the telecommunication signal.

12. A method for enabling a wireless computing device to determine its location both when communicating with one or more satellites of a wireless positioning network and when unable to communicate with any satellites of the wireless positioning network, comprising:

coupling the wireless computing device to the wireless positioning network;

enabling the geographic location of the wireless computing device to be determined upon reception of signals from only the one or more satellites of the wireless positioning network;

creating a database of identification and positional information about non-satellite wireless beacons;

updating the database of identification and positional information about wireless beacons, when the wireless computing device obtains signals from the one or more satellites of the wireless positioning network and determines its geographic location based only on signals therefrom, by

obtaining identification and signal strength information about non-satellite wireless beacons and

deriving positional information about at least one of these wireless beacons, for which identification and signal strength information has been obtained but for which positional information is not present in the database, from the geographic location of the wireless computing device as determined by the wireless computing device and identification and signal strength information obtained b the wireless computing device;

including the derived positional information about the at least one of the wireless beacons in the database; and

when the wireless computing device does not receive usable signals from the one or more satellites of the wireless positioning network to enable it to determine its geographic location based thereon, determining the geographic location of the wireless computing device from reception of signals from at least one non-satellite wireless beacon whose derived positional information is included in the database and analysis of the received signals in light of the positional information about wireless beacons contained in the updated database and from which signals have been received.

13. The method of claim 12, wherein the step of coupling the wireless computing device to the wireless positioning network comprising arranging a GPS device in the wireless computing device.

14. The method of claim 12, wherein the step of updating the database comprises obtaining identification and signal strength data about each wireless beacon at a plurality of locations at which a signal from that wireless beacon is being received and applying an algorithm to determine positional information about the wireless beacons based on the signal strength data.

20. The method of claim 12, wherein the database of identification and positional information about wireless beacons, whose positional information is not already present in the database, is built by obtaining identification and signal strength information about such wireless beacons and deriving positional information for each identified wireless beacon from the signal strength information.

24. The method of claim 12, further comprising locating the database in the wireless computing device.

25. The method of claim 12, wherein the wireless computing device is a Wi-Fi device.

15. A method for administering a database of wireless beacons, comprising:

maintaining a central database of wireless beacons;

wirelessly coupling the central database to a plurality of wireless computing devices;

enabling each wireless computing device to determine identification and positional information about wireless beacons not contained in the central database without communicating with the central database;

periodically forwarding the identification and positional information about wireless beacons not contained in the central database from the wireless computing devices to the central database;

updating the central database to include the forwarded identification and positional information; and

periodically directing the updates of the central database to the plurality of wireless computing devices.

16. The method of claim 15, wherein the step of enabling each wireless computing device to determine identification and positional information about wireless beacons comprises:

obtaining identification and signal strength data about each wireless beacon at a plurality of locations at which a signal from that wireless beacon is being received;

applying an algorithm to determine positional information about the wireless beacons based on the signal strength data; and

storing the positional information in association with the identification data.

17. A system for enabling a wireless computing device to determine its position, comprising:

a central database containing identification and positional information about wireless beacons, said central database being arranged to receive identification and positional information about wireless beacons not previously contained therein and generate database updates based thereon;

a wireless computing device including a local database containing positional information about wireless beacons, said wireless computing device being affanged to wirelessly communicate with said central database to receive said database updates and add said database updates to said local database, said wireless computing device being arranged to determine identification and positional information about wireless beacons, whose positional information is not contained in said central database or said local database, without communicating with said central database and to include the identification and positional information about such wireless beacons in said local database; and

a wireless positioning system substantially collocated with said wireless computing device, said wireless positioning system being arranged to enable the geographic location of said wireless computing device to be determined upon reception of signals from at least one wireless beacon and analysis of the signals in light of the positional information about wireless beacons contained in said local database.

18. The system of claim 17, wherein said wireless positioning system includes a calculation algorithm which determines the geographic location of said wireless computing device upon input of identification and signal strength information about the at least one wireless beacon derived from the received signals.

19. The system of claim 17, wherein said wireless positioning system is arranged in said wireless computing device.