Patent ID: 7508891

Claim:
A method for feeding back antenna shuffling information of transmitted signals in a multiple-input multiple-output (MIMO) system, comprising the steps of: receiving, through two reception antennas, signals transmitted from four transmit antennas; computing mean square error values of the received signals in relation to antenna shuffling information indices of the transmitted signals; and feeding back an index of an antenna shuffling having a minimum mean square error value from among the mean square error values, wherein the index of the antenna shuffling is determined using channel matrix S, where S = [ h 1 , 1 h 1 , 2 h 1 , 3 h 1 , 4 h 1 , 2 * - h 1 , 1 * h 1 , 4 * - h 1 , 3 * h 2 , 1 h 2 , 2 h 2 , 3 h 2 , 4 h 2 , 2 * - h 2 , 1 * h 2 , 4 * - h 2 , 3 * ] , ⁢ and h i,j is a channel gain value between a j-th Tx antenna and an i-th Rx antenna.