A method for feeding back codebook-based precoding matrix information by a receiving side includes estimating a channel through a receiving signal received from a transmitting side; selecting first and second precoding matrix indexes for indicating precoding matrices selected in a predefined codebook based upon said estimated channel; and transmitting said selected first and second precoding matrix indexes to said transmitting side, wherein said predefined codebook supports antenna patterns at the receiving side, precoder (W) in the predefined codebook is expressed as a multiplication of two precoding matrices (W1 and W2), W1 is constituted as an oversampled discrete Fourier transform (DFT) matrix by a diagonal matrix, an element which reflects a factor in accordance with an antenna pattern configuration of said receiving side is included, and said first precoding matrix index indicates a precoding matrix selected from W1 and said second precoding matrix index indicates a precoding matrix selected from W2.