Patent ID: 8483306

Claim:
A pre-coding method, applied to a Multiple-Input Multiple-Output (MIMO) system with eight antennas, and comprising: a transmitting end and a receiving end storing information of a pre-coding codebook together, the receiving end selecting a codeword from the pre-coding codebook according to an estimated channel matrix and feeding back a serial number of the codeword to the transmitting end, and the transmitting end finding out the codeword according to the serial number and pre-coding, by using the codeword, a symbol block sent to the receiving end; wherein, at least eight codeword vectors or column vectors in at least eight codeword matrixes in the pre-coding codebook are obtained based on 8-dimensional vectors selected from the following 8-dimensional vector set: [u 1 s(n) * u 1 ] T , [u 1 −s(n) * u 1 ] T , [u 2 s(n) * u 2 ] T , [u 2 −s(n) * u 2 ] T [u 3 s(n) * u 3 ] T , [u 3 −s(n) * u 3 ] T , [u 4 s(n) * u 4 ] T , [u 4 −s(n) * u 4 ] T [u 5 s(n) * u 5 ] T , [u 5 −s(n) * u 5 ] T , [u 6 s(n) * u 6 ] T , [u 6 −s(n) * u 6 ] T [u 7 s(n) * u 7 ] T , [u 7 −s(n) * u 7 ] T , [u 8 s(n) * u 8 ] T , [u 8 −s(n) * u 8 ] T wherein, u 1 =[1 1 1 1] T , u 2 =[1 j −1 −j] T , u 3 =[1 −1 1 −1] T , u 4 =[1 −j −1 j] T u 5 =[1 q0 j q1] T , u 6 =[1 q1 −j −q0] T , u 7 =[1 q2 j q3] T , u 8 =[1 q3 −j q2] T q0=(1+j)/√{square root over (2)}; q1=(−1+j)/√{square root over (2)}; q2=(−1−j)/√{square root over (2)}; q3=(1−j)/ √{square root over (2)}; s(n)is an element in vectors, n=1,2,3,4, and s=[s(1) s(2) s(3) s(4)]=[1 j q0 q1].