Channel status information feedback method and data transmission method for multiple antenna system

Channel state information feedback method includes receiving a pilot signal and obtains a channel estimation through the received pilot signal. Obtaining the basis indicative of the estimated channel, and feeds back a number of vectors obtained from the basis to the channel state information. Since the use of pre-defined basis, without transmitting the basis directly to the UE to change the basis it can prevent the waste of the transmission channel capacity due to the basis. Further, it is possible to reduce the mismatch between the actual channel basis and it is possible to prevent the waste of the total channel capacity. MIMO, channel state information, CSI, feedback, basis