Apparatus and method for power save mode in wireless local area network

1. A method for a power save mode (PSM) in a wireless local area network, the method comprising:

establishing, by a station, a Tunneled Direct link Setup (TDLS) direct link with a peer station via an access point (AP);

entering, by the station, the power save mode (PSM);

transmitting, by the station after waking up to enter a wakeup state, a PSM request frame to the peer station, the PSM request frame including a wakeup schedule for the PSM, the wakeup schedule including a wakeup window duration and a wakeup interval, the wakeup window duration indicating a duration of a wakeup window, the wakeup interval indicating a time interval between consecutive wakeup windows; and

receiving, by the station, a PSM response frame from the peer station through the TDLS direct link directly in response to the PSM request frame,

wherein the wakeup state is maintained until the PSM response frame is received, and

wherein the PSM request frame is not directly transmitted to the peer station, but the PSM request frame is transmitted to the peer station though the AP.

2. The method of claim 1 , wherein establishing the TDLS direct link includes:

transmitting a TDLS setup request frame to the peer station via the AP;

receiving a TDSL setup response frame in response to the TDLS setup request frame from the peer Station via the AP; and

transmitting a TDSL setup confirm frame in response to the TDSL setup response frame to the peer Station via the AP.

3. The method of claim 1 , wherein the PSM request frame is an encapsulated data frame.

4. The method of claim 1 , wherein the PSM response frame includes a status field indicating acceptance or rejection of the wakeup schedule.

5. The method of claim 4 , wherein if the status field indicates the rejection, the PSM response frame includes an alternative wakeup schedule.

6. The method of claim 1 , wherein the wakeup schedule further includes an idle count indicating the number of consecutive wakeup windows during which no directed frame is received from the peer station before the peer station deletes the wakeup schedule.

7. The method of claim 1 , wherein the wakeup schedule is initiated when the PSM response frame is received.

8. A wireless apparatus for a power save mode (PSM) in a wireless local area network, the wireless apparatus comprising:

an interface unit; and

a processor operatively couples with the interface unit and configured to:

establish a Tunneled Direct link Setup (TDLS) direct link with a peer station via an access point (AP);

enter the power save mode (PSM);

after waking up to enter a wakeup state, transmit a PSM request frame to the peer station, the PSM request frame including a wakeup schedule for the PSM, the wakeup schedule including a wakeup window duration and a wakeup interval, the wakeup window duration indicating a duration of a wakeup window, the wakeup interval indicating a time interval between consecutive wakeup windows; and

receive a PSM response frame from the peer station through the TDLS direct link directly in response to the PSM request frame,

wherein the wakeup state is maintained until the PSM response frame is received, and

wherein the PSM request frame is not directly transmitted to the peer station but the PSM request frame is transmitted to the peer station though the AP.

9. The wireless apparatus of claim 8 , wherein the processor is configured to establish the TDLS direct link by:

transmitting a TDLS setup request frame to the peer station via the AP;

receiving a TDSL setup response frame in response to the TDLS setup request frame from the peer station via the AP; and

transmitting a TDSL setup confirm frame in response to the TDSL setup response frame to the peer Station via the AP.

10. The wireless apparatus of claim 8 , wherein the PSM request frame is an encapsulated data frame.

11. The wireless apparatus of claim 8 , wherein the PSM response frame includes a status field indicating acceptance or rejection of the wakeup schedule.

12. The wireless apparatus of claim 11 , wherein if the status field indicates the rejection, the PSM response frame includes an alternative wakeup schedule.

13. The wireless apparatus of claim 8 , wherein the wakeup schedule further includes an idle count indicating the number of consecutive wakeup windows during which no directed frame is received from the peer station before the peer station deletes the wakeup schedule.

14. The wireless apparatus of claim 8 , wherein the wakeup schedule is initiated when the PSM response frame is received.