Data transmission method and apparatus

A data transmission method, wherein an access point (AP) comprises a first communications apparatus and a second communications apparatus, a first channel is established between the first communications apparatus and a third communications apparatus of a station (STA), a second channel is established between the second communications apparatus and a fourth communications apparatus of the STA, and the first channel and the second channel are channels in different frequency bands;

• and the method comprises:
• receiving, by the second communications apparatus, a second data frame, wherein the second data frame is sent by the first communications apparatus when the first communications apparatus retransmits a first data frame to the third communications apparatus through the first channel, and the first data frame and the second data frame are a same data frame;
• sending, by the second communications apparatus, the second data frame to the fourth communications apparatus through the second channel;
• receiving, by the second communications apparatus, a first acknowledgment message from the fourth communications apparatus through the second channel, wherein the first acknowledgment message indicates that the fourth communications apparatus receives the second data frame through the second channel;
• and
• sending, by the second communications apparatus, a first notification message to the first communications apparatus in response to the first acknowledgment message, wherein the first notification message is used to instruct the first communications apparatus to stop sending the first data frame.

A communications apparatus, comprising:

• a first transceiver configured to retransmit a first data frame after failing to send the first data frame to a third communications apparatus of a station (STA) through a first channel;
• a second transceiver, configured to send a second data frame to a second communications apparatus, wherein the first data frame and the second data frame are a same data frame;
• and further configured to receive a first notification message sent by the second communications apparatus, wherein the first notification message indicates that the second communications apparatus successfully sends the second data frame to a fourth communications apparatus of the STA through a second channel, and the first channel and the second channel are channels in different frequency bands;
• and
• a first controller, configured to stop, in response to the first notification message, sending the first data frame.

A communications apparatus, comprising:

• a third transceiver, configured to receive a second data frame, wherein the second data frame is sent by a first communications apparatus of an access point (AP) when the first communications apparatus retransmits a first data frame to a third communications apparatus of a station (STA) through a first channel, and the first data frame and the second data frame are a same data frame;
• a fourth transceiver, configured to send the second data frame to a fourth communications apparatus of the STA through a second channel;
• and further configured to receive a first acknowledgment message from the fourth communications apparatus through the second channel, wherein the first acknowledgment message indicates that the fourth communications apparatus receives the second data frame through the second channel, and the first channel and the second channel are channels in different frequency bands;
• and
• a second controller, configured to send a first notification message to the first communications apparatus in response to the first acknowledgment message, wherein the first notification message is used to instruct the first communications apparatus to stop sending the first data frame.