A method is presented for transmitting a data packet in a wireless local area network. A physical layer protocol data unit (PPDU) is generated, The PPDU indicates that the PPDU is to be transmitted to a plurality of receivers. The PPDU includes a legacy-short training field (L-STF), a legacy-long training field (LTF), a legacy-signal field (L-SIG), a signal field and a plurality of data streams. The PPDU is transmitted to the plurality of receivers through a plurality of subchannels. The signal field includes stream information and subchannel information. The stream information indicates at least one of the plurality of data streams assigned to each of the plurality of receivers. The subchannel information indicates at least one of the plurality of subchannels through which a corresponding data steam assigned to each of the plurality of receivers is transmitted.