Method and apparatus for retrieving a transmission opportunity control in reverse direction grant

Abstract

Embodiments of the present invention disclose a method and an apparatus for retrieving transmission opportunity control in reverse direction grant, so that a conflict occurring between a case where an RD Initiator continues sending another frame to an RD Responder after retrieving TXOP control and a case where a terminal other than the RD Initiator sends a block acknowledgement to the RD Responder can be avoided. The method provided in the embodiments of the present invention includes: when an RD Initiator fails to correctly demodulate a frame sent by an RD Responder, retrieving, by the RD Initiator, TXOP control by using a PIFS if it is impossible for the RD Responder to enable an MU-MIMO mode, and retrieving, by the RD Initiator, the TXOP control by using a duration if it is possible for the RD Responder to enable the MU-MIMO mode, where the duration is longer than the PIFS.

What is claimed is: 
     
         1 . A method for retrieving a transmission opportunity (TXOP) control in reverse direction grant, comprising:
 obtaining, by a reverse direction responder (RD responder), the TXOP control from a reverse direction initiator (RD initiator);   enabling, by the RD responder, a multi-user multiple-input multiple-output (MU-MIMO) mode;   sending, by the RD responder, a frame to a plurality of stations, which comprise the RD initiator;   wherein the frame carries information that only requires the RD initiator to send back an acknowledgement.   
     
     
         2 . The method for retrieving a TXOP control in reverse direction grant according to  claim 1 , further comprising:
 when the RD initiator fails to correctly demodulate the frame, retrieving, by the RD initiator, the TXOP control by using a point coordination function inter-frame space (PIFS).   
     
     
         3 . A reverse direction responder (RD responder), comprising:
 an obtaining unit, configured to obtain a transmission opportunity (TXOP) control from a reverse direction initiator (RD initiator);   a processing unit, configured to enable a multi-user multiple-input multiple-output (MU-MIMO) mode;   a sending unit, configured to send a frame to a plurality of stations, which comprise the RD initiator;   wherein the frame carries information that only requires the RD initiator to send back an acknowledgement.