1. A method for transmitting data in a wireless local area network, the method comprising: transmitting, by a transmitter, a very high throughput (VHT)-SIG-A field in first subcarriers over first orthogonal frequency division multiplexing (OFDM) symbols to a receiver; transmitting, by the transmitter, a VHT-SIG-B field in second subcarriers over a single second OFDM symbols to the receiver; and transmitting, by the transmitter, a data field in third subcarriers to the receiver, wherein the VHT-SIG-A field, the VHT-SIG-B field and the data field are sequentially transmitted, wherein a number of the second subcarriers is greater than a number of the first subcarriers, and wherein the VHT-SIG-B field is applied by a single column vector and the mapping matrix, the data field is applied by the mapping matrix, and the VHT-SIG-A field is not applied by any of the single column vector and the mapping matrix.