Patent ID: 8194778

Claim:
A method for transmitting a signal in a multiple antenna system, the method performed by a transmitter and comprising: pre-coding the signal based on a codebook comprising first pre-coding matrices; and transmitting the pre-coded signal using a radio resource, wherein each of the first pre-coding matrices is configured in a form of a matrix, which is [ W 0 ⁡ ( i ) W 0 ⁡ ( i ) ] , [ W 0 ⁡ ( i ) - W 0 ⁡ ( i ) ] , [ W 0 ⁡ ( i ) jW 0 ⁡ ( i ) ] ⁢ ⁢ or ⁢ [ W 0 ⁡ ( i ) - jW 0 ⁡ ( i ) ] , wherein W 0 (i) denotes a second pre-coding matrix, wherein i denotes an index for the radio resource, and wherein each of the first pre-coding matrices has 8 rows and the second pre-coding matrix has 4 rows.