Locating a mobile computing unit

• US 7,558,851 B2
• Filed: 11/06/2006
• Issued: 07/07/2009
• Est. Priority Date: 01/12/2001
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Bahl, Paramvir
• Primary Examiner(s): BATES, KEVIN T
• Application Number:
  US11/557,062
• Publication Number:
  US 20070060172A1
• Time in Patent Office: 974 Days
• Field of Search: 709/201, 709/224, 709/223, 709/217, 455/456.6, 455/404.1, 342/118, 342/126
• US Class Current: 709/224
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04L 67/535 Tracking the activity of the user network monitoring arrangements H04L43/00; recording of computer activity G06F11/34
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

System and methods for locating a mobile computing unit are described. In some cases the systems and/or methods determine, at a mobile computing unit, the mobile computing unit'"'"'s absolute coordinates using received radio frequency (“RF”) signals from RF beacons using known coordinates for the RF beacons and an environmental profile. In some other cases, the systems and/or methods determine a location within a building of a mobile computing by receiving RF signals from a plurality of RF beacons having known locations and using a previously established radio map of the building to establish the location within the building of the mobile computing unit.

Claims

1. A method, comprising:

determining, at a mobile computing unit, the mobile computing unit'"'"'s absolute coordinates using received radio frequency (“

‘

RF”

) signals from RF beacons using known coordinates for the RF beacons and an environmental profile of geographic regions inside of a building of a plurality of buildings and geographic regions outside of the buildings; and

transmitting, from the mobile computing unit, the absolute coordinates to a remote computer.

2. The method of claim 1, wherein the act of determining determines that the mobile unit'"'"'s absolute coordinates are within a geographical region.

3. The method of claim 2, wherein the geographical region is a room in the building and wherein the act of transmitting transmits the room of the building to the remote computing unit.

4. The method of claim 2, wherein the geographical region is a room in the building and wherein the environmental profile comprises a radio map of the building.

5. The method of claim 1, wherein the remote computer is a network server.

6. A method, comprising:

determining, at a mobile computing unit, an absolute location of the mobile computing unit, wherein the act of determining the absolute location comprises receiving RF signals from a plurality of RF beacons having known locations and using a previously established radio map of locations inside of a plurality of buildings and locations outside of the buildings to establish the absolute location of the mobile computing unit;

periodically transmitting, from the mobile computing unit, the absolute location of the mobile computing unit to a network server together with a user name of a user using the mobile computing unit;

determining whether the user is actively using the mobile computing unit;

transmitting an active signal with the periodically transmitted information when the user is actively using the mobile computing unit; and

not transmitting the active signal with the periodically transmitted information when the user is not actively using the mobile computing unit.

7. The method as recited in claim 6, wherein the absolute location is a room within the building.

8. The method as recited in claim 6, wherein:

the network server is a wireless network server.

9. The method as recited in claim 6, further comprising time-stamping the transmission to the network server and transmitting the time stamp with the transmitted information.

10. The method as recited in claim 6, wherein the user actively using the mobile computing unit further comprises the user having used the computing unit within a pre-defined time period.

11. The method as recited in claim 6, wherein the periodically transmitting the absolute location of the mobile computer unit to a network server only occurs upon a request from the network server for the mobile computer unit to update the absolute location of the computer unit.

12. The method as recited in claim 6, further comprising encrypting the absolute location of the mobile computing unit prior to transmitting the absolute location of the computing unit to the network server.

13. A mobile computing unit, comprising:

memory;

a wireless network interface configured to connect the mobile computing unit to multiple wireless access points of one or more remote servers;

a location tracking service configured to determine an absolute location of the mobile computer unit utilizing a radio frequency system capable of determining the absolute location by detecting signals transmitted from multiple wireless access points and using a previously established radio map of locations inside of a plurality of buildings and locations outside of the buildings; and

a location manager configured to periodically transmit the absolute location of the mobile computing unit to one or more of the remote servers via the wireless network interface.

14. The mobile computing unit as recited in claim 13, wherein the location manager is further configured to transmit a user name of a user logged onto the mobile computing unit to one or more of the remote servers together with the absolute location of the mobile computing unit.

15. The mobile computing unit as recited in claim 13, wherein the location manager is further configured to transmit an active signal to one or more of the remote servers together with the absolute location of the mobile computing unit when a user logged onto the mobile computing unit has actively used the unit within a specified period of time.

16. The mobile computing unit as recited in claim 13, further comprising a clock, and wherein the location manager is further configured to time-stamp the transmission of information about the absolute location with a time that the transmission is sent.

17. The mobile computing unit as recited in claim 13, wherein the location manager identifies and transmits the absolute location of a network node with which the mobile computing unit is communicating as the absolute location of the mobile computing unit.

18. The mobile computing unit as recited in claim 13, wherein the location manager is configured to invoke the location tracking service when commanded to do so by a second computing unit or one or more of the remote servers.

19. The mobile computing unit as recited in claim 13, wherein the location manager is further configured to encrypt the absolute location of the mobile computing unit before transmitting the absolute location of the mobile computing unit to one or more of the remote servers.