A method, station, and access point for transmitting in a wireless local area network. A method for operating the station includes receiving a beacon signal from an access point in the wireless local area network. The method also includes identifying from the beacon signal a target transmission time of a trigger frame to be transmitted by the access point for an uplink multi-user transmission. A method for operating the access point includes transmitting, to one or more stations in the wireless local area network, a beacon signal that indicates a target transmission time of a trigger frame to be transmitted by the access point for an uplink multi-user transmission.