Distributed multi-user (MU) wireless communication
This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for group formation and sounding for distributed multi-user multiple input multiple output (MU-MIMO). Some implementations include a method of wireless communication. The method includes transmitting, from a first access point of a plurality of access points, an announcement frame for performing a beamforming procedure for a distributed transmission. The distributed transmission includes a transmission from the plurality of access points. The announcement frame includes at least one identifier of a user terminal in a different basic service set than a basic service set of the first access point. The method further includes transmitting a packet for measuring a channel. The method further includes receiving feedback information from the user terminal based on the packet for measuring the channel. The method further includes transmitting the distributed transmission using the beamforming procedure.
1 . An apparatus for wireless communication, the apparatus comprising:
at least one transceiver;
at least one memory storing computer executable code; and
one or more processors coupled to the at least one memory and configured to, individually or collectively, execute the computer executable code to cause the apparatus to:
transmit, via the at least one transceiver, one or more group formation trigger frames;
receive, via the at least one transceiver, from one or more of a plurality of access points and after transmitting the one or more group formation trigger frame, one or more frames that indicate an intent of the one or more access points to participate in a distributed transmission, the distributed transmission being associated with each of the apparatus and the one or more access points;
transmit, via the at least one transceiver and to the one or more access points, a sounding announcement frame, wherein the sounding announcement frame includes an identification of the one or more access points;
transmit, via the at least one transceiver, a sounding packet after transmitting the sounding announcement frame;
receive, via the at least one transceiver and, after transmitting the sounding packet, channel feedback information from one or more user terminals; and
transmit, via the at least one transceiver, a transmission associated with the distributed transmission via beamforming, wherein the beamforming is based on the channel feedback information.
2 . The apparatus of claim 1 , wherein the distributed transmission comprises a downlink multiple user multiple input multiple output (DL MU MIMO) transmission.
3 . The apparatus of claim 1 , wherein at least one of: the one or more group formation trigger frames or the one or more frames that indicate the intent of the one or more access points to participate includes a quantity of spatial streams information.
4 . The apparatus of claim 3 , wherein the spatial streams information includes an indication of a quantity of spatial streams available for transmissions by the one or more access points.
5 . The apparatus of claim 1 , wherein the one or more processors are further configured to, individually or collectively, cause the apparatus to transmit, via the at least one transceiver, a group configuration to the one or more access points.
6 . The apparatus of claim 1 , wherein the one or more processors are further configured to, individually or collectively, cause the apparatus to allocate, via the sounding announcement frame and to at least one of the one or more access points, a spatial stream via which the at least one access point will transmit a packet.
7 . The apparatus of claim 1 , wherein the one or more processors are configured to, individually or collectively, cause the apparatus to, after transmitting the sounding announcement frame, receive, via the at least one transceiver, a second sounding announcement frame from at least one of the one or more access points.
8 . The apparatus of claim 1 , wherein:
the sounding announcement frame includes at least one identifier of a first user terminal, of the one or more user terminals; and
the first user terminal is associated with a different basic service set (BSS) than a BSS of the apparatus.
9 . The apparatus of claim 1 , wherein the one or more processors are further configured to, individually or collectively, cause the apparatus to multiplex the transmission associated with the distributed transmission with the transmissions from each of the one or more access points using one or more of frequency division multiplexing, code division multiplexing, a P-matrix, or time division multiplexing.
10 . The apparatus of claim 1 ,
wherein the apparatus is configured as to operate as one of the plurality of access points.
11 . A method of wireless communication by a first access point of a plurality of access points, the method comprising:
transmitting one or more group formation trigger frames;
receiving, from one or more of the plurality of access points and after transmitting the one or more group formation trigger frame, one or more frames that indicate an intent of the one or more access points to participate in a distributed transmission, the distributed transmission being associated with each of the first access point and the one or more access points;
transmitting, to the one or more access points, a sounding announcement frame, wherein the sounding announcement frame includes an identification of the one or more access points;
transmitting a sounding packet after transmitting the sounding announcement frame;
receiving, after transmitting the sounding packet, channel feedback information from one or more user terminals; and
transmitting a transmission associated with the distributed transmission via beamforming, wherein the beamforming is based on the channel feedback information.
12 . The method of claim 11 , wherein the distributed transmission comprises a downlink multiple user multiple input multiple output (DL MU MIMO) transmission.
13 . The method of claim 11 , wherein at least one of: the one or more group formation trigger frames or the one or more frames that indicate the intent of the one or more access points to participate includes quantity of spatial streams information.
14 . The method of claim 13 , wherein the spatial streams information includes an indication of a quantity of spatial streams available for transmissions by the one or more access points.
15 . The method of claim 11 , further comprising transmitting a group configuration to the one or more access points.
16 . The method of claim 11 , further comprising allocating via the sounding announcement frame and to at least one of the one or more access points, a spatial stream via which the at least one access point will transmit a packet.
17 . The method of claim 11 , further comprising, after transmitting the sounding announcement frame, receive, via the at least one transceiver, a second sounding announcement frame from at least one of the one or more access points.
18 . The method of claim 11 , wherein:
the sounding announcement frame includes at least one identifier of a first user terminal, of the one or more user terminals; and
the first user terminal is associated with a different basic service set (BSS) than a BSS of the first access point.
19 . The method of claim 11 , further comprising multiplexing the transmission associated with the distributed transmission with the transmissions from each of the one or more access points using one or more of frequency division multiplexing, code division multiplexing, a P-matrix, or time division multiplexing.
20 . A first access point of a plurality of access points, comprising:
at least one transceiver;
at least one memory storing computer executable code; and
one or more processors coupled to the at least one memory and configured to, individually or collectively, execute the computer executable code to cause the first access point to:
transmit, via the at least one transceiver, one or more group formation trigger frames;
receive, via the at least one transceiver, from one or more of the plurality of access points and after transmitting the one or more group formation trigger frame, one or more frames that indicate an intent of the one or more access points to participate in a distributed transmission, the distributed transmission being associated with each of the first access point and the one or more access points;
transmit, via the at least one transceiver, to the one or more access points, a sounding announcement frame, wherein the sounding announcement frame includes an identification of the one or more access points;
transmit, via the at least one transceiver, a sounding packet after transmitting the sounding announcement frame;
receive, via the at least one transceiver, after transmitting the sounding packet, channel feedback information from one or more user terminals; and
transmit, via the at least one transceiver, a transmission associated with the distributed transmission via beamforming, wherein the beamforming is based on the channel feedback information.