Patent ID: 8107455

Claim:
A method for transmitting a signal in a multiple antenna system, the method performed by a transmitter and comprising: generating a first group of pre-coding matrices including [ 1 1 1 1 ] , [ 1 1 j - j ] , [ 1 1 - 1 - 1 ] , [ 1 1 - j j ] , [ 1 j 1 - j ] , [ 1 j j - 1 ] , [ 1 j - 1 j ] , [ 1 j - j 1 ] , [ 1 - 1 1 - 1 ] , ⁢ [ 1 - 1 j j ] , [ 1 - 1 - 1 1 ] , [ 1 - 1 - j - j ] , [ 1 - j 1 j ] , [ 1 - j j 1 ] , [ 1 - j j 1 ] , [ 1 - j - 1 - j ] , and ⁢ [ 1 - j - j - 1 ] ; rotating a phase of a fourth row of the first pre-coding matrices using a phase value of −π; applying an antenna power normalization factor to the first pre-coding matrices; generating a second group of pre-coding matrices including 1 2 ⁡ [ 1 0 1 0 ] , 1 2 ⁡ [ 1 0 - 1 0 ] , 1 2 ⁡ [ 1 0 j 0 ] , 1 2 ⁡ [ 1 0 - j 0 ] , 1 2 ⁡ [ 0 1 0 1 ] , 1 2 ⁡ [ 0 1 0 - 1 ] , 1 2 ⁡ [ 0 1 0 j ] ⁢ ⁢ and 1 2 ⁡ [ 0 1 0 - j ] ; pre-coding the signal based on a codebook comprising the first group of pre-coding matrices and the second group of pre-coding matrices; and transmitting the pre-coded signal using a radio resource.