Backoff counter and TXOP duration settings for coordinated access point transmissions
This disclosure provides systems, methods and apparatuses for wireless communications. In some implementations, a first access point (AP) may identify other APs to participate in a coordinated access point transmission session, may obtain a transmit opportunity (TXOP) for transmitting wireless signals over a frequency bandwidth, may allocate corresponding portions of the frequency bandwidth to the identified APs for downlink (DL) transmissions during the TXOP, may select a duration of the TXOP for the coordinated access point transmission session based at least in part on an amount or percentage of the first AP's frequency bandwidth that is allocated to the one or more identified APs for the coordinated access point transmission session, and may output information indicative of at least one of the selected TXOP duration or the corresponding portions of the frequency bandwidth allocated to the respective identified AP by the first AP.
1. A method for wireless communication performed by a first access point (AP), comprising:
identifying one or more other APs to participate with the first AP in a coordinated access point transmission session;
allocating, to each AP of the one or more identified APs, a corresponding portion of a frequency bandwidth for use during a TXOP;
selecting a duration of the TXOP for the coordinated access point transmission session based at least in part on an amount or percentage of the frequency bandwidth that is allocated to at least one of the one or more identified APs for the coordinated access point transmission session;
transmitting, to each AP of the one or more identified APs, information indicative of the duration of the TXOP and the corresponding portion of the frequency bandwidth allocated to the respective AP;
transmitting, to each AP of the one or more identified APs, information indicative of a timing associated with one or more symbols of a first protocol data unit (PDU) to be transmitted by the first AP; and
transmitting the first PDU in accordance with the timing.
2. The method of claim 1 , wherein the identifying comprises:
advertising the coordinated access point transmission session;
receiving, from each AP of one or more nearby APs, information indicating a request to participate in the coordinated access point transmission session; and
identifying the one or more APs participating in the coordinated access point transmission session based on the information received from the one or more nearby APs.
3. The method of claim 1 , wherein the allocating comprises:
transmitting, to each AP of the one or more identified APs, a request for a preferred bandwidth to be allocated by the first AP for the coordinated access point transmission session;
receiving, from each AP of the one or more identified APs, a response indicating the preferred bandwidth to be allocated by the first AP; and
determining the corresponding portions of the frequency bandwidth to be allocated to the one or more identified APs based on at least one of the preferred bandwidths indicated by the one or more identified APs.
4. The method of claim 3 , wherein the response further indicates a preferred number of spatial streams to be used by the respective identified AP for the coordinated access point transmission session.
5. The method of claim 1 , further comprising transmitting, to each AP of the one or more identified APs, an indication of a number of spatial streams to be used by the respective identified AP for transmissions during the TXOP.
6. The method of claim 1 , wherein each of the corresponding portions of the frequency bandwidth allocated by the first AP includes a respective resource unit.
7. The method of claim 1 , further comprising transmitting a frame that solicits the identified APs to advertise their respective corresponding portions of the frequency bandwidth.
8. The method of claim 1 , wherein the first AP transmits the first PDU concurrently with transmissions of PDUs from the one or more identified APs on their respective corresponding portions of the frequency bandwidth.
9. The method of claim 1 , wherein transmitting the information indicative of the timing associated with the one or more symbols of the first PDU comprises transmitting a trigger frame that includes the information indicative of the timing.
10. The method of claim 1 , further comprising:
contending for medium access based on decrementing a back-off counter during successive contention periods;
gaining medium access and commencing the TXOP based on the back-off counter being less than a value; and
indicating, to each of the one or more identified APs, an ability to pause decrementing of the respective back-off counter of the identified AP during the TXOP.
11. The method of claim 10 , further comprising:
indicating, to each of the one or more identified APs, an ability to contend for medium access during a next contention period using the paused values of their respective back-off counters.
12. A first wireless access point (AP) comprising:
at least one modem;
at least one processor communicatively coupled with the at least one modem; and
at least one memory communicatively coupled with the at least one processor and storing processor-readable code that, when executed by the at least one processor in conjunction with the at least one modem, is configured to perform operations comprising:
identifying one or more other APs to participate with the first AP in a coordinated access point transmission session;
allocating, to each AP of the one or more identified APs, a corresponding portion of a frequency bandwidth for use during a TXOP;
selecting a duration of the TXOP for the coordinated access point transmission session based at least in part on an amount or percentage of the frequency bandwidth that is allocated to at least one of the one or more identified APs for the coordinated access point transmission session;
transmitting, to each AP of the one or more identified APs, information indicative of the duration of the TXOP and the corresponding portion of the frequency bandwidth allocated to the respective AP;
transmitting, to each AP of the one or more identified APs, information indicative of a timing associated with one or more symbols of a first protocol data unit (PDU) to be transmitted by the first AP; and
transmitting the first PDU in accordance with the timing.
13. The first AP of claim 12 , wherein execution of the processor-readable code for identifying the one or more other APs causes the first AP to perform operations further comprising:
advertising the coordinated access point transmission session;
receiving, from each AP of one or more nearby APs, information indicating a request to participate in the coordinated access point transmission session; and
identifying the one or more APs participating in the coordinated access point transmission session based on the information received from the one or more nearby APs.
14. The first AP of claim 12 , wherein execution of the processor-readable code for allocating the corresponding portions causes the first AP to perform operations further comprising:
transmitting, to each AP of the one or more identified APs, a request for a preferred bandwidth to be allocated by the first AP for the coordinated access point transmission session;
receiving, from each AP of the one or more identified APs, a response indicating the preferred bandwidth to be allocated by the first AP; and
determining the corresponding portions of the frequency bandwidth to be allocated to the one or more identified APs based on at least one of the preferred bandwidths indicated by the one or more identified APs.
15. The first AP of claim 14 , wherein the response further indicates a preferred number of spatial streams to be used by the respective identified AP for the coordinated access point transmission session.
16. The first AP of claim 12 , wherein execution of the processor-readable code further causes the first AP to transmit, to each AP of the one or more identified APs, an indication of a number of spatial streams to be used by the respective identified AP for transmissions during the TXOP.
17. The first AP of claim 12 , wherein each of the corresponding portions of the frequency bandwidth allocated by the first AP includes a respective resource unit.
18. The first AP of claim 12 , wherein execution of the processor-readable code further causes the first AP to transmit a frame that solicits the identified APs to advertise their respective corresponding portions of the frequency bandwidth.
19. The first AP of claim 12 , wherein the first AP transmits the first PDU concurrently with transmissions of PDUs from the one or more identified APs on their respective corresponding portions of the frequency bandwidth.
20. The first AP of claim 12 , wherein transmitting the information indicative of the timing associated with the one or more symbols of the first PDU comprises transmitting a trigger frame that includes the information indicative of the timing.
21. The first AP of claim 12 , wherein execution of the processor-readable code further causes the first AP to perform operations comprising:
contending for medium access based on decrementing a back-off counter during successive contention periods;
gaining medium access and commencing the TXOP based on the back-off counter being less than a value; and
indicating, to each of the one or more identified APs, an ability to pause decrementing of the respective back-off counter of the identified AP during the TXOP.
22. The first AP of claim 21 , wherein execution of the processor-readable code further causes the first AP to perform operations comprising:
after an end of the TXOP, resetting the back-off counter of the first AP and indicating, to each of the one or more identified APs, an ability to contend for medium access during a next contention period using the paused values of their respective back-off counters.