Patent ID: 9078251
Filing Date: 2015-07-07
Classification: H04B,H04L,H04W

Abstract:
1. A method of transmitting a data frame by a transmitter in a wireless local area network system, the method comprising: generating a data block including at least one data unit respectively transmitted through at least one spatial stream to at least one receiver; transmitting first control information to the at least one receiver, the first control information comprising a length indicator, a multiple input multiple output (MIMO) indicator, and a spatial stream indication field, the length indicator indicating a length of the at least one data unit, the MIMO indicator indicating whether the at least one data unit is for a SU (single user)-MIMO transmission or a MU (multi user)-MIMO transmission, the spatial stream indication field comprising information about a number of the at least one spatial stream; transmitting second control information to the at least one receiver, the second control information comprising a modulation and coding scheme (MCS) field indicating an MCS applied to the at least one data unit; and transmitting the data block to the at least one or more receivers, wherein, when the MIMO indicator indicates that the at least one data unit is for the MU transmission, the spatial stream indication field includes a plurality of subfields, each of the plurality of subfields indicating a number of spatial streams used for transmitting a corresponding data unit.