Power saving in peer-to-peer communication devices

• US 8,203,985 B2
• Filed: 12/31/2008
• Issued: 06/19/2012
• Est. Priority Date: 12/31/2008
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Gong, Michelle Xiaohong, Stephens, Adrian P., Jalfon, Mark, Tai, Tsung-Yuan Charles
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Elallam, Ahmed
• Application Number:
  US12/317,969
• Publication Number:
  US 20100165896A1
• Time in Patent Office: 1,266 Days
• Field of Search: 370/311
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 76/14 Direct-mode setup
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Apparatuses, systems, methods, and computer program products to save power in peer-to-peer communication devices associated with wireless communication networks are disclosed. Embodiments generally comprise wireless communications devices. A device may associate or connect with an access point and communicate with another device also connected to the access point. The devices may establish a direct link as part of a tunneled direct link system (TDLS) network. After establishing the direct link, the devices may negotiate a wakeup schedule, enabling both devices to enter power saving modes to conserve power. The devices may maintain the direct link while in power saving modes, enabling the devices to periodically exit the power saving modes and transfer buffered data.

Claims

1. A method, comprising:

negotiating, by a first station with a second station, a wakeup schedule for the first station and the second station to exchange data, wherein the negotiating is via a direct link between the first station and the second station, wherein further the direct link comprises a wireless peer-to-peer link of a tunneled direct link setup (TDLS) network, the negotiating comprising;

determining by the first station an acceptable wakeup frequency of another wakeup schedule; and

accepting by the first station the wakeup schedule, wherein the wakeup schedule was proposed by the second station, and the wakeup schedule contains a higher wakeup frequency than the wakeup frequency of the other wakeup schedule pursuant to a rule requiring the first station to accept a wakeup schedule proposed by a peer station, wherein the first station determined an acceptable wakeup schedule and the peer station proposes a wakeup schedule with a higher wakeup frequency than the acceptable wakeup schedule;

entering by the first station a first mode of power saving according to the wakeup schedule while the second station is in a second mode of power saving; and

exiting by the first station the first mode based on the wakeup schedule.

2. The method of claim 1, wherein the negotiating the wakeup schedule comprises negotiating values for a start time of a wakeup window, a duration of a wakeup window, and an interval between successive wakeup windows.

3. The method of claim 2, wherein:

the first station and the second station have established communication links with an access point; and

the negotiating comprises agreeing upon the start time, the start time not a gcd of the interval between successive wakeup windows and a beacon interval of the access point.

4. The method of claim 1, further comprising:

establishing by the first station a direct link with a third station;

receiving, by the first station from the third station, a proposed wakeup schedule with a higher wakeup frequency than the wakeup frequency of the wakeup schedule;

rejecting by the first station the proposed wakeup schedule; and

proposing a third wakeup schedule more in alignment with the wakeup schedule pursuant to a rule allowing the first station to reject a wakeup schedule proposed by a peer station in order to have a wakeup schedule more in alignment with a wakeup schedule currently in effect.

5. The method of claim 1, further comprising:

rejecting, by the first station, another wakeup schedule proposed by the second station; and

providing, by the first station to the second station, reasons for the rejection of the other wakeup schedule proposed by the second station.

6. The method of claim 1, further comprising:

proposing, by the first station, before receiving the wakeup schedule from the second station, a wakeup schedule;

receiving, by the first station from the second station, a rejection of the proposed wakeup schedule; and

refraining from proposing an alternative wakeup schedule for an interval of time pursuant to a rule requiring the first station to refrain from proposing a wakeup schedule for a fixed interval of time after receiving a rejection.

7. The method of claim 1, wherein:

the negotiating comprises;

transmitting by the first station to the second station a first request frame comprising a unique identifier; and

transmitting by the first station to the second station a subsequent request frame, comprising a field referencing the unique identifier of the first request frame, in response to the first station not receiving from the second station a reply to the first request frame.

8. An apparatus, comprising:

a power mode module to enable a communication device to switch to a power saving mode and to resume full-power operations;

a data transference module to transfer data between the communication device and a second communication device, wherein the data transference module is to transfer data via a direct link between the communication device and the second communication device, wherein further the direct link comprises a wireless link of a tunneled direct link setup (TDLS) network; and

an operations scheduling module to negotiate a wakeup schedule of the communication device, wherein the wakeup schedule comprises;

a start time for the communication device to exit the power saving mode and for the second communication device to exit a second power saving mode;

one or more positive durations of a wakeup window; and

one or more intervals between successive wakeup windows, wherein;

the wakeup schedule comprises either two or more positive durations of a wakeup window or two or more intervals between successive wakeup windows;

the wakeup schedule comprises conditions for switching from a first positive duration of a wakeup window to a second positive duration or for switching from a first interval between successive wakeup windows to a second interval between successive wakeup windows; and

the power mode module is to enable the communication device to switch to a power saving mode pursuant to the negotiated wakeup schedule and to resume full-power operations for a duration of a wakeup window of the wakeup schedule.

9. The apparatus of claim 8, further comprising a clock to enable the operations scheduling module to determine when a start time of a wakeup window arrives.

10. The apparatus of claim 8, wherein:

the one or more intervals between successive wakeup windows comprise a first interval between wakeup windows and a second interval between wakeup windows; and

the operations scheduling module is to dynamically select between the first interval and the second interval based on an amount of data transferred between the communication device and the second communication device.

11. The apparatus of claim 10, wherein the operations scheduling module is to select a second wakeup schedule proposed by the second communication device.

12. The apparatus of claim 8, wherein:

the one or more positive durations of a wakeup window comprise a first positive duration of a wakeup window and a second positive duration of a wakeup window; and

the operations scheduling module is to dynamically select between the first positive duration of a wakeup window and the second positive duration of a wakeup window based on an amount of data transferred between the communication device and the second communication device.

13. The apparatus of claim 8, wherein:

the one or more intervals between successive wakeup windows comprise a first interval between successive wakeup windows and a second interval between successive wakeup windows; and

the wakeup schedule is to schedule the first interval between successive wakeup windows for a first period of time and to schedule the second interval between successive wakeup windows for a second period of time.

14. The apparatus of claim 8, wherein the data transference module is to transfer to the second communication device an acknowledgement of a data frame received from the second communication device during a wakeup window, the acknowledgement to contain a data field indicating whether the first communication device has data to transfer to the second communication device during the wakeup window.

15. The apparatus of claim 8, wherein the data transference module is to transmit at least one frame of data to the second communication device during each wakeup window pursuant to a policy requiring the transmission of at least frame of data during each wakeup window.

16. A system, comprising:

memory to store a wakeup schedule and buffered data, wherein the memory comprises dynamic random access memory (DRAM);

a wireless communication device coupled to the memory, wherein;

the wireless communication device is arranged to transfer the buffered data between the system and a peer station via a direct link of a tunneled direct link setup (TDLS) network; and

the wireless communication device comprises a power mode module to enable the wireless communication device to switch to a power saving mode and to resume full-power operations; and

an operations scheduling module to negotiate the wakeup schedule, wherein the wakeup schedule comprises;

a start time for the wireless communication device to exit a power saving mode and for the second communication device to exit a second power saving mode;

one or more positive durations of a wakeup window; and

one or more intervals between successive wakeup windows, wherein;

the wakeup schedule comprises conditions for switching from a first positive duration of a wakeup window to a second positive duration or for switching from a first interval between successive wakeup windows to a second interval between successive wakeup windows; and

the power mode module is to enable the communication device to switch to a power saving mode pursuant to the negotiated wakeup schedule and to resume full-power operations for a duration of a wakeup window of the wakeup schedule.

17. The system of claim 16, wherein the operations scheduling module comprises an application specific integrated circuit (ASIC).

18. The system of claim 16, wherein:

the one or more positive durations of a wakeup window comprise a first positive duration of a wakeup window and a second positive duration of a wakeup window; and

the operations scheduling module is arranged to dynamically select between the first positive duration of a wakeup window and the second positive duration of a wakeup window based on an amount of data transferred between the wireless communication device and the peer station.

19. The system of claim 16, wherein:

the one or more intervals between successive wakeup windows comprise a first interval between successive wakeup windows and a second interval between successive wakeup windows; and

the wakeup schedule is to schedule the first interval between successive wakeup windows for a first period of time and to schedule the second interval between successive wakeup windows for a second period of time.

20. The system of claim 16, wherein the wireless communication device is to transfer to the peer station an acknowledgement of a data frame received from the peer station during a wakeup window, the acknowledgement to contain a data field indicating whether the wireless communication device has data to transfer to the peer station during the wakeup window.

21. The system of claim 16, wherein the wireless communication device is to transmit at least one frame of data to the peer station during each wakeup window pursuant to a policy requiring the transmission of at least frame of data during each wakeup window.

22. A computer program product comprising:

a computer readable tangible storage medium, wherein the storage medium does not comprise a transitory signal, wherein the storage medium includes instructions that, when executed by a processor;

buffer data to be transferred from a first peer station to a second peer station, wherein transference of the buffered data is via a direct link of a tunneled direct link setup (TDLS) network, wherein further the direct link comprises a wireless link; and

negotiate a wakeup schedule, the negotiating comprising;

determining by the first peer station an acceptable wakeup frequency of another wakeup schedule; and

accepting by the first peer station the wakeup schedule, wherein the wakeup schedule was proposed by the second peer station, and the wakeup schedule contains a higher wakeup frequency than the wakeup frequency of the other wakeup schedule pursuant to a rule requiring the first peer station to accept a wakeup schedule proposed by a peer station, wherein the first peer station determined an acceptable wakeup schedule and the peer station proposes a wakeup schedule with a higher wakeup frequency than the acceptable wakeup schedule, wherein the wakeup schedule specifies a time that the first peer station and the second peer station are to exit doze states to transfer the buffered data.

23. The computer program product of claim 22, further comprising instructions that maintain the direct link after the first peer station enters a first doze state and the second peer station enters a second doze state.

24. The computer program product of claim 22, wherein the instructions that negotiate the wakeup schedule comprises instructions that transmit a TDLS power save mode (PSM) request frame, wherein further the TDLS PSM request frame comprises a wakeup schedule information element with an element identification field, a length field, a start time field to indicate a start time of a wakeup window, an interval field to indicate an interval between successive wakeup windows, a duration of awake window field, and an idle count field.

25. The computer program product of claim 22, further comprising instructions that:

establish by the first peer station a direct link with a third peer station;

receive, by the first peer station from the third peer station, a proposed wakeup schedule with a higher wakeup frequency than the wakeup frequency of the wakeup schedule; and

propose by the first peer station a third wakeup schedule more in alignment with the wakeup schedule pursuant to a rule allowing the first peer station to reject a wakeup schedule proposed by a peer station in order to have a wakeup schedule more in alignment with a wakeup schedule currently in effect.