Map coordination of NSTR constrained links
Methods and apparatuses for facilitating multi-AP (MAP) coordination to mitigate interference caused by a link of a non-simultaneous transmit/receive (NSTR) link pair of a multi-link device (MLD) in an overlapping basic service set (OBSS) in a wireless local area network. The methods include a method performed by an access point (AP) MLD, comprising the steps of obtaining, via a backhaul link from a neighboring AP in a different BSS, a MAP coordination request that includes schedule information for a victim station (STA) in the different BSS, and modifying, based on the MAP coordination request and the schedule information, an operation mode of either the AP MLD or a non-AP MLD that forms an NSTR link pair with the AP MLD, such that a first link of the NSTR link pair is silenced during an active period of the victim STA.
1 . An access point (AP) multi-link device (MLD), comprising:
APs each comprising a transceiver configured to form a link with a corresponding station (STA) of a non-AP MLD, wherein at least two of the links form a non-simultaneous transmit/receive (NSTR) link pair; and
a processor operably coupled to the APs, the processor configured to:
obtain, via a backhaul link from a neighboring AP in a different basic service set (BSS), a multi-AP (MAP) coordination request that includes schedule information for a victim STA in the different BSS, and
modify, based on the MAP coordination request and the schedule information, an operation mode of either the AP MLD or the non-AP MLD such that a first link of the NSTR link pair is silenced during an active period of the victim STA.
2 . The AP MLD of claim 1 , wherein the processor is further configured to:
determine, based on the MAP coordination request, whether downlink (DL) traffic or uplink (UL) traffic on the first link causes interference at the victim STA, and
determine to silence the DL traffic on the first link during the active period based on a determination that the DL traffic causes the interference, or
determine to silence the UL traffic on the first link during the active period based on a determination that the UL traffic causes the interference.
3 . The AP MLD of claim 1 , wherein the processor is further configured to:
instruct a first AP that forms the first link to wait to begin a first DL traffic transmission on the first link until the active period has ended, and
instruct a second AP that forms a second link of the NSTR link pair to pad a second DL traffic transmission on the second link that begins during the active period, such that an end time of the second DL traffic transmission aligns with an end time of the first DL traffic transmission.
4 . The AP MLD of claim 1 , wherein the processor is further configured to:
switch the AP MLD to a single link operation mode using a second link of the NSTR link pair during the active period, and
instruct a second AP that forms the second link to complete a DL traffic transmission operation on the second link before the end of the active period.
5 . The AP MLD of claim 1 , wherein:
the processor is further configured to generate a message that instructs the non-AP MLD to:
instruct a first STA that forms the first link to wait to begin a first UL traffic transmission on the first link until the active period has ended;
instruct a second STA that forms a second link of the NSTR link pair to wait to begin a second UL traffic transmission on the second link until the active period has ended; and
instruct the first STA and the second STA to begin the first and second UL traffic transmissions simultaneously, and
at least one of the transceivers is configured to transmit the message to the non-AP MLD.
6 . The AP MLD of claim 1 , wherein:
the processor is further configured to generate a message that instructs the non-AP MLD to:
switch to a single link operation mode using a second link of the NSTR link pair during the active period; and
instruct a second STA that forms the second link to complete a UL traffic transmission operation on the second link before the end of the active period, and
at least one of the transceivers is configured to transmit the message to the non-AP MLD.
7 . The AP MLD of claim 1 , wherein the processor is configured to send, to the neighboring AP over the backhaul link, a MAP coordination response indicating that the first link will be silenced during the active period.
8 . A non-access point (AP) multi-link device (MLD) comprising:
stations (STAs) each comprising a transceiver configured to form a link with a corresponding AP of an AP MLD, wherein at least two of the links form a non-simultaneous transmit/receive (NSTR) link pair; and
a processor operably coupled to the STAs, the processor configured to modify, based on a multi-AP (MAP) coordination request and schedule information for a victim STA in a different basic service set (BSS), an operation mode of the non-AP MLD such that a first link of the NSTR link pair is silenced during an active period of the victim STA.
9 . The non-AP MLD of claim 8 , wherein the processor is further configured to modify the operation mode of the non-AP MLD based on a determination to silence uplink (UL) traffic on the first link during the active period based on a determination that the UL traffic causes interference at the victim STA.
10 . The non-AP MLD of claim 8 , wherein:
the transceiver of a first STA that forms the first link is further configured to receive a first downlink (DL) traffic transmission on the first link after the active period has ended,
the transceiver of a second STA that forms a second link of the NSTR link pair is further configured to receive a second DL traffic transmission on the second link after the active period has ended, and
the second DL traffic transmission is padded such that an end time of the second DL traffic transmission aligns with an end time of the first DL traffic transmission.
11 . The non-AP MLD of claim 8 , wherein:
the transceiver of a second STA that forms a second link of the NSTR link pair is further configured to receive a second DL traffic transmission on the second link under a single link operation mode that uses the second link, and
the second DL traffic transmission is completed before the end of the active period.
12 . The non-AP MLD of claim 8 , wherein:
at least one of the transceivers is configured to receive a message from the AP MLD that includes instructions for the non-AP MLD, and
the processor is further configured to, based on the instructions:
switch to a single link operation mode using a second link of the NSTR link pair during the active period; and
instruct a second STA that forms the second link to complete a UL traffic transmission operation on the second link before the end of the active period.
13 . The non-AP MLD of claim 8 , wherein:
at least one of the transceivers is configured to receive a message from the AP MLD that includes instructions for the non-AP MLD, and
the processor is further configured to, based on the instructions:
instruct a first STA that forms the first link to wait to begin a first UL traffic transmission on the first link until the active period has ended;
instruct a second STA that forms a second link of the NSTR link pair to wait to begin a second UL traffic transmission on the second link until the active period has ended; and
instruct the first STA and the second STA to begin the first and second UL traffic transmissions simultaneously.
14 . A method of wireless communication performed by an access point (AP) multi-link device (MLD), the method comprising:
obtaining, via a backhaul link from a neighboring AP in a different basic service set (BSS), a multi-AP (MAP) coordination request that includes schedule information for a victim station (STA) in the different BSS; and
modifying, based on the MAP coordination request and the schedule information, an operation mode of either the AP MLD or a non-AP MLD that forms a non-simultaneous transmit/receive (NSTR) link pair with the AP MLD, such that a first link of the NSTR link pair is silenced during an active period of the victim STA.
15 . The method of claim 14 , further comprising:
determining, based on the MAP coordination request, whether downlink (DL) traffic or uplink (UL) traffic on the first link causes interference at the victim STA; and
determining to silence the DL traffic on the first link during the active period based on a determination that the DL traffic causes the interference; or
determining to silence the UL traffic on the first link during the active period based on a determination that the UL traffic causes the interference.
16 . The method of claim 14 , further comprising:
instructing a first AP of the AP MLD that forms the first link to wait to begin a first DL traffic transmission on the first link until the active period has ended; and
instructing a second AP of the AP MLD that forms a second link of the NSTR link pair to pad a second DL traffic transmission on the second link that begins during the active period, such that an end time of the second DL traffic transmission aligns with an end time of the first DL traffic transmission.
17 . The method of claim 14 , further comprising:
switching the AP MLD to a single link operation mode using a second link of the NSTR link pair during the active period; and
instructing a second AP of the AP MLD that forms the second link to complete a DL traffic transmission operation on the second link before the end of the active period.
18 . The method of claim 14 , further comprising:
generating a message that instructs the non-AP MLD to:
instruct a first STA of the non-AP MLD that forms the first link to wait to begin a first UL traffic transmission on the first link until the active period has ended,
instruct a second STA of the non-AP MLD that forms a second link of the NSTR link pair to wait to begin a second UL traffic transmission on the second link until the active period has ended, and
instruct the first STA and the second STA to begin the first and second UL traffic transmissions simultaneously; and
transmitting the message to the non-AP MLD.
19 . The method of claim 14 , further comprising:
generating a message that instructs the non-AP MLD to:
switch to a single link operation mode using a second link of the NSTR link pair during the active period; and
instruct a second STA of the non-AP MLD that forms the second link to complete a UL traffic transmission operation on the second link before the end of the active period, and
transmitting the message to the non-AP MLD.
20 . The method of claim 14 , further comprising sending, to the neighboring AP over the backhaul link, a MAP coordination response indicating that the first link will be silenced during the active period.