Multiple input multiple output (MIMO) setup in millimeter wave (MMW) WLAN systems
An AP/PCP may perform user selection/pairing/grouping based on a measurement of an analog transmission (e.g., signal to noise ratio (SNR) or signal to interference plus noise ratio (SINR)). The SNRs may be used, for example by the station, to determine best beams and/or beam pairs and/or worst beams and/or beam pairs. A station may feed back the best few beams and/or beam pairs for a Tx and Rx virtual antenna pair. A station may feed back the worst few beams for the Tx and Rx virtual antenna pair. The AP/PCP may receive the indication(s) and/or use the indication(s) to group the stations.
1. A station (STA) configured for multi-user multiple-input multiple-output (MU-MIMO) communications, the STA comprising:
a processor;
transmitter circuitry configured to transmit a MU-MIMO setup frame to a group of responder STAs comprising at least a first responder STA and a second responder STA, for configuring the group to receive MU-MIMO transmissions from the STA, wherein the setup frame indicates a first antenna allocation for MU-MIMO transmissions from the STA to the first responder STA and a second antenna allocation for MU-MIMO transmissions from the STA to the second responder STA, wherein the first antenna allocation is different from the second antenna allocation;
the transmitter circuitry configured to transmit first MU-MIMO transmissions to the first responder STA based on the first antenna allocation and second MU-MIMO transmissions to the second responder STA based on the second antenna allocation; and
receiver circuitry configured to receive a response frame from the first responder STA in response to the first MU-MIMO transmissions and a response frame from the second responder STA in response to the second MU-MIMO transmissions.
2. The STA of claim 1 , wherein the first antenna allocation comprises a first set of radio frequency (RF) chains, and the second antenna allocation comprises a second set of RF chains.
3. The STA of claim 1 , wherein the first antenna allocation comprises a first set of virtual antennas, and the second antenna allocation comprises a second set of virtual antennas.
4. The STA of claim 1 , wherein a first number of spatial streams comprising the first MU-MIMO transmissions is different from a second number of spatial streams comprising the second MU-MIMO transmissions.
5. The STA of claim 1 , wherein the MU-MIMO setup frame comprises an enhanced directional multi-gigabit (EDMG) MU-MIMO setup frame.
6. The STA of claim 1 , wherein the MU-MIMO setup frame comprises a medium access control (MAC) frame.
7. The STA of claim 1 , wherein the STA comprises an access point (AP).
8. The STA of claim 1 , further configured to transmit an end frame to a responder STA of the group.
9. The STA of claim 1 , further configured to transmit an end frame to a responder STA of the group on a condition that the STA does not receive a response frame from the responder STA of the group in response to MU-MIMO transmissions.
10. The STA of claim 1 , wherein the group comprises a third responder STA; and the MU-MIMO setup frame indicates a third antenna allocation for MIMO transmissions from the STA to the third responder STA, wherein the third antenna allocation is different from the first antenna allocation, the second antenna allocation, or both the first and the second antenna allocation.
11. A method for multi-user multiple-input multiple-output (MU-MIMO) communications implemented in a station (STA), the method comprising:
transmitting, by transmitter circuitry of the STA, a MU-MIMO setup frame to a group of responder STAs comprising at least a first responder STA and a second responder STA, for configuring the group to receive MU-MIMO transmissions from the STA, wherein the setup frame indicates a first antenna allocation for MU-MIMO transmissions from the STA to the first responder STA and a second antenna allocation for MU-MIMO transmissions from the STA to the second responder STA, wherein the first antenna allocation is different from the second antenna allocation;
transmitting, by the transmitter circuitry, first MU-MIMO transmissions to the first responder STA based on the first antenna allocation and second MU-MIMO transmissions to the second responder STA based on the second antenna allocation; and
receiving, by receiver circuitry of the STA, a response frame from the first responder STA in response to the first MU-MIMO transmissions and a response frame from the second responder STA in response to the second MU-MIMO transmissions.
12. The method of claim 11 , wherein the first antenna allocation comprises a first set of radio frequency (RF) chains, and the second antenna allocation comprises a second set of RF chains.
13. The method of claim 11 , wherein the first antenna allocation comprises a first set of virtual antennas, and the second antenna allocation comprises a second set of virtual antennas.
14. The method of claim 11 , wherein a first number of spatial streams comprising the first MU-MIMO transmissions is different from a second number of spatial streams comprising the second MU-MIMO transmissions.
15. The method of claim 11 , wherein the MU-MIMO setup frame comprises an enhanced directional multi-gigabit (EDMG) MU-MIMO setup frame.
16. The method of claim 11 , wherein the MU-MIMO setup frame comprises a medium access control (MAC) frame.
17. The method of claim 11 , wherein the STA comprises an access point (AP).
18. The method of claim 11 , further comprising transmitting an end frame to a responder STA of the group.
19. The method of claim 11 , further comprising transmitting an end frame to a responder STA of the group on a condition that the STA does not receive a response frame from the responder STA of the group in response to MU-MIMO transmissions.
20. The method of claim 11 , wherein the group comprises a third responder STA; and the MU-MIMO setup frame indicates a third antenna allocation for MIMO transmissions from the STA to the third responder STA, wherein the third antenna allocation is different from the first antenna allocation, the second antenna allocation, or both the first and the second antenna allocation.