An apparatus of an access point, AP, (102, 250) configured for transmit beamforming and downlink, DL, multiuser, MU, multiple-input multiple output, MIMO, DL-MU-MIMO, operation, the apparatus comprising: means to encode a null data packet, NDP, announcement frame, NDP-A, and an a high-efficiency, HE, NDP, the NDP-A followed by the HE NDP to initiate an HE sounding protocol, the HE NDP configured to be transmitted a short interframe space, SIFS, after transmission of the NDP-A; means to encode a receiver address, RA, of the NDP-A to indicate a broadcast address to solicit multi-user, MU, feedback; means to configure the HE NDP to include, following a legacy signal field, L-SIG, an HE long training field, HE-LTF, comprising training signals, and one or more HE signal fields, HE-SIGs; means to encode a trigger frame (431, 500) for transmission a SIFS after the HE NDP, the trigger frame (431, 500) identifying each of a plurality of stations, STAs, the trigger frame (431, 500) to indicate channel resources (530, 540) that the STAs are to use for transmission of sounding feedback; means to decode HE compressed beamforming feedback frames received from the STAs, the HE compressed beamforming feedback frames received within a same transmission opportunity, TXOP, during which the trigger frame was transmitted, wherein the HE compressed beamforming feedback frames are based on receipt of the training signals and include beam-forming measurements related to one or more links between the AP and the respective STAs; and means to determine parameters for beamforming from the training signals and the HE compressed beamforming feedback frames for a beamformed DL-MU-MIMO transmission to the STAs. means to encode a null data packet, NDP, announcement frame, NDP-A, and an a high-efficiency, HE, NDP, the NDP-A followed by the HE NDP to initiate an HE sounding protocol, the HE NDP configured to be transmitted a short interframe space, SIFS, after transmission of the NDP-A; means to encode a receiver address, RA, of the NDP-A to indicate a broadcast address to solicit multi-user, MU, feedback; means to configure the HE NDP to include, following a legacy signal field, L-SIG, an HE long training field, HE-LTF, comprising training signals, and one or more HE signal fields, HE-SIGs; means to encode a trigger frame (431, 500) for transmission a SIFS after the HE NDP, the trigger frame (431, 500) identifying each of a plurality of stations, STAs, the trigger frame (431, 500) to indicate channel resources (530, 540) that the STAs are to use for transmission of sounding feedback; means to decode HE compressed beamforming feedback frames received from the STAs, the HE compressed beamforming feedback frames received within a same transmission opportunity, TXOP, during which the trigger frame was transmitted, wherein the HE compressed beamforming feedback frames are based on receipt of the training signals and include beam-forming measurements related to one or more links between the AP and the respective STAs; and means to determine parameters for beamforming from the training signals and the HE compressed beamforming feedback frames for a beamformed DL-MU-MIMO transmission to the STAs.