USING WIRELESS CHARACTERISTIC TO TRIGGER GENERATION OF POSITION FIX

• US 20090098903A1
• Filed: 09/16/2008
• Published: 04/16/2009
• Est. Priority Date: 08/31/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Palm, Inc. (TCL Technology Group Corp.)
• Inventors: Donaldson, Jesse E., Mahe, Isabel Ge, Paulson, Janell, Tsuk, Robert, Ramaswamy, Gurunath, Hamilton, Craig C., Ballot, Edward C., Kansal, Sachin S.
• Granted Patent: US 9,071,701 B2
• Time in Patent Office: Days
• US Class Current: 455/552.1
• CPC Class Codes: G01S 19/258 relating to the satellite constellation, e.g. almanac, ephemeris data, lists of satellites in view
• CPC Class Codes: G01S 2205/006 for emergency situations
• CPC Class Codes: H04M 1/72403 with means for local support of applications that increase the functionality
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04M 1/72457 according to geographic location
• CPC Class Codes: H04M 2250/02 including a Bluetooth interface
• CPC Class Codes: H04M 2250/06 including a wireless LAN interface
• CPC Class Codes: H04M 2250/10 including a GPS signal receiver
• 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 52/0245 according to signal strength
• CPC Class Codes: H04W 52/028 switching on or off only a part of the equipment circuit blocks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless characteristic of a wireless signal may be used to trigger generation of a position fix. A mobile computing device may include a wireless transceiver, a location determination circuit and a processing circuit. The wireless transceiver may be configured to receive a wireless signal over a short range wireless network from a wireless system. The processing circuit may be configured to detect a change in the wireless signal and, in response to the detected change, to generate a position fix using the location determination circuit.

Claims

1. A mobile computing device, comprising:

a wireless transceiver configured to receive wireless messages from a plurality of wireless systems;

a memory configured to store a position fix; and

a processor configured to detect a change from receiving wireless messages from a first wireless system to receiving wireless messages from a second wireless system and, in response, to generate an updated position fix.

2. The mobile computing device of claim 1, wherein the change is in an overhead message of wireless messages received by the wireless transceiver.

3. The mobile computing device of claim 1, wherein the change is in a system ID/network ID of wireless messages received by the wireless transceiver.

4. The mobile computing device of claim 1, wherein the change is in IDs associated with the first and second wireless systems operating according to an IEEE 802.11 wireless standard.

5. The mobile computing device of claim 4, wherein the IDs are SSIDs.

6. The mobile computing device of claim 1, further comprising a location determination circuit configured to generate the updated position fix based at least in part on signals from global positioning system satellites.

7. The mobile computing device of claim 1, wherein the location determination circuit comprises a first mode in which position fixes are obtained periodically and a second mode in which position fixes are not obtained periodically, wherein the location determination circuit switches from the second mode to the first mode in response to the detected change.

8. A mobile computing device, comprising:

a wireless transceiver configured to receive a wireless signal over a short range wireless network from a wireless system;

a location determination circuit; and

a processing circuit configured to detect a change in the wireless signal and, in response to the detected change, to generate a position fix using the location determination circuit.

9. The mobile computing device of claim 8, wherein the wireless transceiver is configured to receive the wireless signal over the wireless network operating according to at least one of an IEEE 802.11 protocol and a Bluetooth protocol.

10. The mobile computing device of claim 8, wherein the change is a change in signal strength of the wireless signal below a predetermined threshold.

11. The mobile computing device of claim 8, wherein the change is a change in signal strength of the wireless signal above a predetermined threshold.

12. The mobile computing device of claim 8, wherein the change is a loss of the wireless signal.

13. The mobile computing device of claim 8, wherein the processing circuit is configured to store the position fix and an identifier of the wireless system.

14. The mobile computing device of claim 13, wherein the processing circuit is configured to control a display to display position display data based on the position fix and wireless system display data based on the identifier of the wireless system.

15. The mobile computing device of claim 14, wherein the position display data and wireless system display data are displayed on a map.

16. The mobile computing device of claim 8, wherein the wireless transceiver is configured to receive the wireless signal over the wireless network operating according to at least one of an IEEE 802.11 protocol and a Bluetooth protocol, wherein the processing circuit is configured to store the position fix and an identifier of the wireless system and to control a display to display an indication of a location of the wireless system.

17. The mobile computing device of claim 8, wherein the change is indicative that the wireless signal was not previously being received and is now being received.

18. A method, comprising:

storing a position fix on a mobile computing device;

receiving at least one identifier of a wireless device over a short range wireless network; and

based on a change in the identifier or identifiers received, updating the position fix on the mobile computing device.

19. The method of claim 18, wherein the at least one identifier is an SSID and the short range wireless network is a Wi-Fi network.

20. The method of claim 19, wherein the change comprises no longer receiving the at least one identifier or receiving a new identifier.

21. The method of claim 20, further comprising, based on the change of identifier or identifiers received, switching the mobile computing device to a mode in which the position fix is updated periodically.

22. The method of claim 18, further comprising retrieving local traffic information to the mobile computing device based on the change in identifier, wherein the change in identifier comprises receipt of an identifier previously known to the mobile computing device.