POWER MANAGEMENT

• US 20070197186A1
• Filed: 02/06/2007
• Published: 08/23/2007
• Est. Priority Date: 02/06/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Olympus Corporation
• Inventors: Muqattash, Alaa, Heidari-Bateni, Ghoabad
• Granted Patent: US 7,751,357 B2
• Time in Patent Office: Days
• US Class Current: 455/343.1
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

According to an embodiment of the invention the timing of one or more local communication windows can be defined using equations such that one or more local communication windows for two or more devices overlap. For example the periods between two consecutive local communication windows can be defined using a periodic equation such as: LAP Cycle Period=Δ*2ⁿ. In this equation n=0, 1, 2, . . . , N, where N and Δ can be fixed. For example, N and Δ can be numbers that are predetermined for a given network, a given set of network devices, etc. In one embodiment every device can become active every Δ*2ⁿ superframes. The frequency (n) can be determined based on, for example, incoming or outgoing message traffic, power consumption needs, etc.

Claims

1. A method of power management, comprising:

defining a global communication window, having a periodicity defined by a periodic relationship;

transmitting a local communication window, having a periodicity defined by a periodic relationship to other devices in a network;

waking from a hibernation state at a predetermined time for the local communication window;

receiving a transmission from another device in the network during the local communication window; and

returning to the hibernation state after the local communication window.

2. The method of claim 1, wherein the relationships defining the periodicity of the global and the local communication windows are equations.

3. The method of claim 2, wherein the equation defining the global communication window is Δ

*2^m.

4. The method of claim 2, wherein the equation defining the local communication window is Δ

*2ⁿ.

5. The method of claim 4, wherein n is determined, at least in part, based on message traffic.

6. The method of claim 4, wherein n is determined, at least in part, based on power consumption needs.

7. The method of claim 4, wherein n is determined, at least in part, based on a devices available battery life.

8. The method of claim 2, wherein the equation defining the global communication window is Δ

*2^m and the equation defining the local communication window is Δ

*2ⁿ.

9. The method of claim 8, wherein n is equal to the largest value of n for a given neighborhood.

10. The method of claim 1, further comprising selecting an Active Cycle Start Time that is advertised for a particular beaconing group.

11. The method of claim 10, further comprising a device selecting an Active Cycle Start Time if no beacon is received.

12. A network device comprising:

a memory, the memory configured to store instructions;

a processor coupled to the memory and configured to execute the instructions to perform the following steps;

defining a global communication window, having a periodicity defined by a periodic relationship;

transmitting a local communication window, having a periodicity defined by a periodic relationship to other devices in a network;

waking from a hibernation state at a predetermined time for the local communication window;

receiving a transmission from another device in the network during the local communication window; and

returning to the hibernation state after the local communication window.

13. The method of claim 12, wherein the relationships defining the periodicity of the global and the local communication windows are equations.

14. The method of claim 13, wherein the equation defining the global communication window is Δ

*2^m.

15. The method of claim 13, wherein the equation defining the local communication window is Δ

*2ⁿ.

16. The method of claim 15, wherein n is determined, at least in part, based on message traffic.

17. The method of claim 15, wherein n is determined, at least in part, based on power consumption needs.

18. The method of claim 15, wherein n is determined, at least in part, based on a devices available battery life.

19. The method of claim 13, wherein the equation defining the global communication window is Δ

*2^m and the equation defining the local communication window is Δ

*2ⁿ.

20. The method of claim 19, wherein n is equal to the largest value of n for a given neighborhood.

21. The method of claim 12, further comprising selecting an Active Cycle Start Time that is advertised for a particular beaconing group.

22. The method of claim 21, further comprising a device selecting an Active Cycle Start Time if no beacon is received.