Patent ID: 8848817

Claim:
A method of transmitting data in a wireless communication system, comprising the steps of: forming one or more layers of data stream wherein each of the data streams consists of modulated symbols; generating an 8-by-N precoding matrix based on a precoding matrix indicator (PMI) feedback from at least one remote receiver wherein the PMI indicates a choice of precoding matrix W derived from a matrix multiplication of two matrices W 1 and W 2 from a first codebook C 1 and a second codebook C 2 , respectively, wherein the first codebook C 1 contains at least the following matrices when the number of layers N is one or two: ⁢ B = [ b 0 b 1 … b 15 ] , [ B ] 1 + m , 1 + n = ⅇ j ⁢ 2 ⁢ π ⁢ ⁢ mn 16 , ⁢ ⁢ m = 0 , 1 , 2 , 3 ⁢ ⁢ n = 0 , 1 , … ⁢ , 15 X ( k ) ∈ { [ b ( 2 ⁢ k ) ⁢ mod ⁢ ⁢ 16 b ( 2 ⁢ k + 1 ) ⁢ mod ⁢ ⁢ 16 b ( 2 ⁢ k + 2 ) ⁢ mod ⁢ ⁢ 16 b ( 2 ⁢ k + 3 ) ⁢ mod ⁢ ⁢ 16 ] ⁢ : ⁢ ⁢ k = 0 , 1 , …7 } ⁢ W 1 ( k ) = [ X ( k ) 0 0 X ( k ) ] , C 1 = { W 1 ( 0 ) , W 1 ( 1 ) , W 1 ( 2 ) , … ⁢ , W 1 ( 7 ) } ; precoding the one or more layers of data stream via multiplication with the 8-by-N precoding matrix where N is the number of said layers; and transmitting the precoded layers of data stream to the remote receiver.