Method and system for supporting residual energy awareness in an ad hoc wireless communications network

• US 7,463,886 B2
• Filed: 11/12/2003
• Issued: 12/09/2008
• Est. Priority Date: 09/16/2003
• Status: Active Grant

• Current Assignee: Intellectual Ventures I LLC (Intellectual Ventures LLC)
• Original Assignee: Spyder Navigations LLC (Intellectual Ventures LLC)
• Inventors: Celentano, Ulrico, Palin, Arto, Salokannel, Juha, Reunamäki, Jukka, Kaaja, Harald
• Primary Examiner(s): Gesessse; Tilahun B
• Application Number:
  US10/704,744
• Publication Number:
  US 20050075084A1
• Time in Patent Office: 1,854 Days
• Field of Search: 455/41.1, 455/445, 455/436, 455/439, 455/426.1, 455/562, 455/574, 455/343.2, 455/426.2, 455/464, 455/343.4, 455/465, 455/67.11, 455/343.5, 455/522, 370/338
• US Class Current: 455/426.1
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 52/0277 according to available power supply, e.g. switching off when a low battery condition is detected
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 84/20 Master-slave selection or change arrangements
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless communications device detects a change in its residual energy status, and transmits the residual energy status across a wireless communications network to a remote device that coordinates communications in the wireless communications network. For example, the remote device may be a piconet coordinator (PNC) in an IEEE 802.15.3 network, or a master device in a Bluetooth network. A wireless communications device that coordinates communications in a wireless communications network (the coordinator) transmits one or more first handover commands to one or more remote devices upon the occurrence of a triggering event. Based on responses to these first commands, the coordinator selects a remote device for coordinating future communications in the wireless communications network.

Claims

1. A method in a wireless communications device, the method comprising:

(a) coordinating wireless communications in a wireless communications network, the wireless communications network including the wireless communications device and a plurality of remote devices;

(b) maintaining a database, the database storing at least residual energy status information for each of plurality of remote devices;

(c) receiving updated residual energy status information from a remote device of the plurality of remote devices;

wherein

a first class is assigned to the remote device if the remote device receives power from a fixed power supply;

a second class is assigned to the remote device if a residual energy percentage level of the remote device is greater than a first percentage value; and

a third class is assigned to the remote device if a residual energy percentage level of the remote device is less than a second percentage value;

(d) dynamically updating the database based on the received information; and

(e) selecting one of the plurality of remote devices as a best candidate for coordinating future communications in the wireless communications network, said selection based on at least the class assignment.

2. The method of claim 1, further comprising:

determining the residual energy percentage level.

3. The method of claim 1, wherein:

the first percentage value is approximately 66 percent;

and the second percentage value is approximately 33 percent; and

further wherein a third class is assigned to the remote device if the residual energy percentage level of the remote device is less than the first percentage value and greater than the second percentage value.

4. The method of claim 1, wherein assigning the residual energy level class further comprises:

assigning a third class indicating the wireless communications device is always available to coordinate wireless communications in the wireless communications network;

assigning a fourth class indicating the wireless communications device is currently available to coordinate wireless communications in the wireless communications network;

assigning a fifth class indicating the wireless communications device does not desire to coordinate wireless communications in the wireless communications network; and

assigning a sixth class indicating the wireless communications device is not available to coordinate wireless communications in the wireless communications network.

5. The method of claim 1, wherein the fixed power supply is an alternating current (AC) power supply.

6. The method of claim 1, which further comprises transmitting an indicator of the residual energy level class to the remote device.

7. The method of claim 1, wherein the wireless communications device is a master device in a Bluetooth network.

8. The method according to claim 1, wherein the wireless communications device is an IEEE 802.15.3 piconet coordinator (PNC).

9. The method of claim 1, wherein step c) comprises receiving the residual energy status information in one or more capabilities information elements (IEs).

10. The method of claim 9, wherein the one or more capabilities IEs include a PNC Des-mode bit and a PSRC bit.

11. The method of claim 1, wherein step c) comprises receiving the residual energy status information in a PNC probe request.

12. The method of claim 1, wherein the residual status information includes an energy level class indicator corresponding to the residual energy percentage level of the corresponding remote device.

13. The method of claim 1, wherein step (e) comprises selecting one of the plurality of remote devices based on a plurality of priorities, wherein one of the priorities corresponds to the stored residual energy status information.

14. The method of claim 1, wherein step (b) comprises storing the plurality of priorities in the database.

15. The method of claim 1, further comprising transferring the database to the remote device selected in step (e).

16. The method of claim 1, wherein step (e) is performed upon the occurrence of a triggering event.

17. A wireless communications device, comprising:

a wireless communications portion for communicating with a plurality of remote devices in a wireless communications network;

a memory; and

a processor that executes instructions stored in the memory for;

coordinating wireless communications in the wireless communications network;

maintaining a database, the database storing at least residual energy status information for each of plurality of remote devices;

receiving updated residual energy status information from a remote devices or the plurality of remote devices;

wherein

a first class is assigned to the remote device if the remote device receives power from a fixed power supply;

a second class is assigned to the remote device if a residual energy percentage level of the remote device is greater than a first percentage value; and

a third class is assigned to the remote device if a residual energy percentage level of the remote device is less than a second percentage value;

dynamically updating the database based on the received information;

selecting one of the plurality of remote devices as a best candidate for coordinating future communications in the wireless communications network, said selection based on at least class assignment.

18. A wireless communications device, comprising:

means for coordinating wireless communications in a wireless communications network, the wireless communications network including the wireless communications device and a plurality of remote devices;

information for each of remote devices;

means for maintaining a database, the database storing at least residual energy status information for each of plurality of remote devices;

means for receiving updated residual energy status information from a remote device of the plurality of remote devices;

wherein

a first class is assigned to the remote device if the remote device receives power from a fixed power supply;

a second class is assigned to the remote device if a residual energy percentage level of the remote device is greater than a first percentage value; and

a third class is assigned to the remote device if a residual energy percentage level of the remote device is less than a first percentage value;

means for dynamically updating the database based on the received information; and

means for selecting one of the plurality of remote devices as a best candidate for coordinating future communications in the wireless communications network, said selection based on at least the class assignment.

19. A computer program product in computer useable medium having computer program logic recorded thereon for enabling a processor to operate in a wireless communications device, the computer program logic configured to:

coordinate wireless communications in a wireless communications network, the wireless communications network including the wireless communications device and a plurality of remote devices;

maintain a database, the database storing at least residual energy status information for each of plurality of remote devices;

receive updated residual energy status information from a remote devices of the plurality of remote devices;

wherein

a first class is assigned to the remote device if the remote device receives power from a fixed power supply;

a second class is assigned to the remote device if a residual energy percentage level of the remote device is greater than a first percentage value; and

a third class is assigned to the remote device if a residual energy percentage level of the remote device is less than a second percentage value;

update the database based on the received information; and

select one of the plurality of remote devices as a best candidate for coordinating future communications in the wireless communications network, said selection based on at least the class assignment.