Patent ID: 8493836

Claim:
A method for controlling a user equipment (UE) to transmit a Single Carrier-Frequency Division Multiple Access (SC-FDMA) symbol via multiple antennas, the method comprising: mapping codewords to three layers, wherein the layers indicate virtual spatial resources; performing Discrete Fourier Transform (DFT) spreading upon each of the three layers; generating precoded signals by precoding the three layers using a specific precoding matrix selected from a prestored codebook; performing a predetermined process for constructing the SC-FDMA symbol upon the precoded signals; and transmitting the SC-FDMA symbol to a base station (BS) via the multiple antennas, wherein the prestored codebook consists of 20 precoding matrices selected from 12 precoding matrix groups [ 1 0 0 X 0 0 0 1 0 0 0 1 ] , [ 1 0 0 0 1 0 X 0 0 0 0 1 ] , [ 1 0 0 0 1 0 0 0 1 X 0 0 ] , [ 0 1 0 1 0 0 X 0 0 0 0 1 ] , [ 0 1 0 1 0 0 0 0 1 X 0 0 ] , ⁢ [ 0 1 0 0 0 1 1 0 0 X 0 0 ] , [ 1 2 0 0 X 2 0 0 0 1 0 0 0 1 ] , [ 1 2 0 0 0 1 0 X 2 0 0 0 0 1 ] , [ 1 2 0 0 0 0 1 0 1 0 X 2 0 0 ] , ⁢ [ 0 1 0 1 2 0 0 X 2 0 0 0 0 1 ] , [ 0 0 1 1 2 0 0 0 1 0 X 2 0 0 ] ⁢ ⁢ and ⁢ [ 0 1 0 0 0 1 1 2 0 0 X 2 0 0 ] , to each of which a predetermined constant is multiplied, wherein X is a variable having an amplitude of 1.