For example, an apparatus may include circuitry and logic configured to cause a wireless communication station (STA) to determine a plurality of uplink (UL) sounding groups of STAs; transmit at least one trigger frame to at least one UL sounding group of the plurality of UL sounding groups to trigger a measurement procedure with the UL sounding group, the trigger frame including one or more Identifiers (IDs) to identify one or more STAs of the UL sounding group; to receive one or more UL Null Data Packet (NDP) sounding frames from the one or more STAs of the UL sounding group in response to the trigger frame; to transmit a downlink (DL) NDP Announcement (NDP-A) frame to the plurality of UL sounding groups; and to transmit a DL NDP sounding frame to the plurality of UL sounding groups.