A wireless communications network is provided. The wireless communications network comprises a plurality of base stations. Each one of said base stations is capable of wireless communications with a plurality of subscriber stations. At least one of said plurality of base stations comprises a processor configured to select a codeword from a codebook and precode data with the selected codeword, and a transmitter configured to transmit the precoded data. Rank 1 of the codebook is selected from the following algorithm: Codebook Matrix Index (CMI)Base MatrixRank 1 1V8(:, :, 3)V8(:, 1, 3) 2 V8(:, 2, 3) 3 V8(:, 3, 3) 4 V8(:, 4, 3) 5 V8(:, 5, 3) 6 V8(:, 6, 3) 7 V8(:, 7, 3) 8 V8(:, 8, 3) 9 V8(:, 9, 3) 10 V8(:, 10, 3) 11 V8(:, 11, 3) 12 V8(:, 12, 3) 13 V8(:, 13, 3) 14 V8(:, 14, 3) 15 V8(:, 15, 3) 16 V8(:, 16, 3).