Method and device for transmitting and receiving ppdu on basis of fdd in wireless lan system

A non-access point multi-link device (non-AP MLD) in a wireless local area network (WLAN) system, the non-AP MLD comprising:

• a memory;
• a transceiver;
• and
• a processor operatively coupled to the memory and the transceiver, wherein the processor is configured to:
• receive a first data from an AP MLD;
• and
• transmit a second data to the AP MLD,
• wherein the non-AP MLD includes a first non-AP station (STA) and a second non-AP STA,
• wherein the AP MLD includes a first AP and a second AP,
• wherein the AP MLD sets up first and second links with the non-AP MLD, and
• wherein the second AP receives the second data from the second non-AP STA through the second link, while the first AP transmits the first data to the first non-AP STA through the first link.

A method in a wireless local area network (WLAN) system, the method comprising:

• transmitting, by an access point multi-link device (AP MLD), a first data to a non-AP MLD;
• and
• receiving, by the AP MLD, a second data from the non-AP MLD,
• wherein the non-AP MLD includes a first non-AP station (STA) and a second non-AP STA,
• wherein the AP MLD includes a first AP and a second AP,
• wherein the AP MLD sets up first and second links with the non-AP MLD, and
• wherein the second AP receives the second data from the second non-AP STA through the second link, while the first AP transmits the first data to the first non-AP STA through the first link.