Hello, friend!
In Wi-Fi standard evolution, 802.11ac Wave 2 (Wi-Fi 5) introduces MU-MIMO, specifically DL MU-MIMO, which allows an AP to send data to a maximum of four terminals at the same time. In 802.11ax (Wi-Fi 6), UL MU-MIMO is introduced to solve the bottleneck of uplink multi-user transmission. In addition, the maximum number of STAs allowed to communicate with APs at the same time is increased to eight, further improving transmission efficiency in densely populated scenarios. Therefore, if the Wi-Fi device supports Wi-Fi 5, DL MU-MIMO is supported, and if the Wi-Fi device supports Wi-Fi 6, bidirectional MU-MIMO is supported.
It should be noted that, for MU-MIMO to take effect, APs and terminals of both communicating parties need to support MU-MIMO. If there are UEs that do not support MU-MIMO on the network, the AP still uses SU-MIMO when communicating with such UEs, and continues to use MU-MIMO when communicating with UEs that support MU-MIMO.
Thanks!