Method for exchanging frame for low power device and apparatus therefore in wireless lan system therefor

Patent metadata

Field	Value
Publication number	US-2016014773-A1
Application number	US-201314769082-A
Country	US
Kind code	A1
Filing date	Oct 13, 2013
Priority date	Feb 24, 2013
Publication date	Jan 14, 2016
Grant date	—

Abstract

The present invention relates to a wireless communication system, and more particularly to a method for exchanging a frame for a low power device and an apparatus therefor in a wireless LAN system. A method for enabling an access point (AP) to exchange a frame with a station (STA) in a wireless LAN system according to an embodiment of the present invention includes the steps of receiving the information of the maximum awake time from the STA. When the frame exchange is expected to be accomplished within the maximum awake time, the frame exchange can be performed. When the frame exchange is expected to exceed the maximum awake time, the frame exchange is stopped, and a new back-off procedure can be invoked.

First claim

What is claimed is:

1 . A method for allowing an access point (AP) to perform frame exchange with a station (STA) in a wireless LAN (WLAN) system, comprising:
receiving information regarding a maximum awake time from the station (STA); if it is expected that the frame exchange will be completed within the maximum awake time, performing the frame exchange; and if it is expected that the frame exchange will exceed the maximum awake time, stopping the frame exchange, and performing a new backoff process.

2 . The method according to claim 1 , wherein the AP assumes that the maximum awake time starts from a specific time at which the access point (AP) receives a PS (Power Save)-Poll frame from the station (STA).

3 . The method according to claim 1 , wherein the information regarding the maximum awake time is received from the station (STA) by the access point (AP) through a probe request frame, an association request frame, or a reassociation request frame.

4 . The method according to claim 1 , wherein the station (STA) is an energy limited station (STA).

5 . The method according to claim 1 , wherein the frame exchange includes:
transmitting the PS-Poll frame from the station (STA) to the access point (AP); and transmitting an ACK frame from the access point (AP) to the station (STA).

6 . The method according to claim 5 , wherein the PS-Poll frame includes indication information indicating that information regarding some bytes of a Time Synchronization Function (TSF) timer is requested.

7 . The method according to claim 5 , wherein the ACK frame includes information regarding some bytes of the TSF timer of the access point (AP).

8 . The method according to claim 6 , wherein the some bytes of the TSF timer are a predetermined number of lower bytes of the TSF timer of the access point (AP).

9 . The method according to claim 5 , wherein the PS-Poll frame is transmitted when the station (STA) awakes.

10 . The method according to claim 5 , wherein the PS-Poll frame is transmitted on the condition that the station (STA) does not listen to a beacon.

11 . A method for allowing a station (STA) to perform frame exchange with an access point (AP) in a wireless LAN (WLAN) system, comprising:
transmitting information regarding a maximum awake time to the access point (AP); if it is expected that the frame exchange will be completed within the maximum awake time, performing the frame exchange; and if it is expected that the frame exchange will exceed the maximum awake time, stopping the frame exchange, and performing a new backoff process.

12 . An access point (AP) for performing frame exchange with a station (STA) in a wireless LAN (WLAN) system, comprising:
a transceiver; and a processor, wherein the processor controls the transceiver to receive information regarding a maximum awake time from the station (STA); if it is expected that the frame exchange will be completed within the maximum awake time, performs the frame exchange; and if it is expected that the frame exchange will exceed the maximum awake time, stops the frame exchange, and performs a new backoff process.

13 . A station (STA) for performing frame exchange with an access point (AP) in a wireless LAN (WLAN) system, comprising:
a transceiver; and a processor, wherein the processor controls the transceiver to transmit information regarding a maximum awake time to the access point (AP); if it is expected that the frame exchange will be completed within the maximum awake time, performs the frame exchange; and if it is expected that the frame exchange will exceed the maximum awake time, stops the frame exchange, and performs a new backoff process.

Assignees

• Lg Electronics Inc

Inventors

• Seok Yongho

Classifications

• H04W84/12

  WLAN [Wireless Local Area Networks] · CPC title

• H04W76/38

  triggered by timers · CPC title

• H04W52/0216

  using a pre-established activity schedule, e.g. traffic indication frame · CPC title

• H04W74/06

  using polling · CPC title

• H04W74/08 Primary

  Non-scheduled access, e.g. ALOHA (hybrid access H04W74/02) · CPC title