Method and device for multi-link EDCA information sharing
In a wireless local area network (WLAN) system, an AP multi-link device (MLD) may estimate an uplink transmission time of a non-simultaneous transmit and receive (STR) station (STA) MLD, and on the basis of the time estimation, uplink transmission and downlink transmission in links of the non-STR STA MLD may not overlap.
1. A method performed by an access point (AP) multi-link device (MLD) of a wireless local area network (WLAN) system, the method comprising:
receiving, by a first AP affiliated with the AP MLD, a physical protocol data unit (PPDU) from a first non-AP station (STA) affiliated with a non-AP MLD through a first link,
wherein the first AP operates in the first link, a second AP is further affiliated with the AP MLD, and the first non-AP STA operates in the first link,
wherein the PPDU includes a legacy signal (L-SIG) field, a repeated L-SIG (RL-SIG) field being contiguous to the L-SIG field, and a first signal (SIG) field being contiguous to the RL-SIG field,
wherein the L-SIG field includes a length field, and a value of the length field is set to satisfy a condition that a remainder is zero (0) when the value of the length field is divided by three (3), and
wherein the first SIG field includes first bit information related to a PPDU type, second bit information related to an identifier of a basic service set (BSS), third bit information indicating duration information related to a TXOP, fourth bit information related to whether the PPDU is sent in uplink (UL) or in downlink (DL), fifth bit information related to a bandwidth, and sixth bit information having a length of 3 bits and indicating a physical (PHY) version of the PPDU,
wherein the PPDU further includes a data field including information related to a backoff counter (BC) of the first non-AP STA and information related to channel utilization;
calculating, by the first AP affiliated with the AP MLD, an estimated time for uplink transmission of the first non-AP STA in the first link, based on the information related to the BC and the information related to the channel utilization; and
determining, by the first AP affiliated with the AP MLD, a destination of downlink transmission in a second link, based on the estimated time,
wherein the estimated time is calculated as follows:
estimated time=BC/(1−channel utilization).
2. The method of claim 1 , wherein the information related to the BC includes BC information per every access category (AC) of traffic to be transmitted by the first non-AP STA.
3. The method of claim 1 , wherein the information related to the BC includes BC information of a top-priority AC of traffic to be transmitted by the first non-AP STA.
4. The method of claim 1 , wherein the information related to the BC includes information on a smallest BC among all AC BCs of traffic to be transmitted by the first non-AP STA.
5. An access point (AP) multi-link device (MLD) used in a wireless local area network (WLAN) system, the AP MLD comprising:
a transceiver transmitting and receiving a radio signal; and
a processor connected to the transceiver, wherein the processor is adapted to:
receive, by a first AP affiliated with the AP MLD, a physical protocol data unit (PPDU) from a first non-AP station (STA) affiliated with a non-AP MLD through a first link,
wherein the first AP operates in the first link, a second AP is further affiliated with the AP MLD, and the first non-AP STA operates in the first link,
wherein the PPDU includes a legacy signal (L-SIG) field, a repeated L-SIG (RL-SIG) field being contiguous to the L-SIG field, and a first signal (SIG) field being contiguous to the RL-SIG field,
wherein the L-SIG field includes a length field, and a value of the length field is set to satisfy a condition that a remainder is zero (0) when the value of the length field is divided by three (3), and
wherein the first SIG field includes first bit information related to a PPDU type, second bit information related to an identifier of a basic service set (BSS), third bit information indicating duration information related to a TXOP, fourth bit information related to whether the PPDU is sent in uplink (UL) or in downlink (DL), fifth bit information related to a bandwidth, and sixth bit information having a length of 3 bits and indicating a physical (PHY) version of the PPDU,
wherein the PPDU further includes a data field including information related to a backoff counter (BC) of the first non-AP STA and information related to channel utilization;
calculate, by the first AP affiliated with the AP MLD, an estimated time for uplink transmission of the first non-AP STA in the first link, based on the information related to the BC and the information related to the channel utilization; and
determine, by the first AP affiliated with the AP MLD, a destination of downlink transmission in a second link, based on the estimated time,
wherein the estimated time is calculated as follows:
estimated time=BC/(1−channel utilization).
6. The AP MLD of claim 5 , wherein the information related to the BC includes BC information per every access category (AC) of traffic to be transmitted by the first non-AP STA.
7. The AP MLD of claim 5 , wherein the information related to the BC includes BC information of a top-priority AC of traffic to be transmitted by the first non-AP STA.
8. The AP MLD of claim 5 , wherein the information related to the BC includes information on a smallest BC among all AC BCs of traffic to be transmitted by the first non-AP STA.