Patent ID: 8351540

Claim:
A codebook creating method, comprising: determining a codebook size N and a symbol set Ψ, by a network equipment, according to at least one of the following elements: 1 2 ⁡ [ 1 0 1 / 2 α 0 - α / 2 0 1 γ / 2 0 β - βγ / 2 ] , 1 2 ⁡ [ 1 0 1 / 2 0 1 γ ⁢ 2 α 0 - α / 2 0 β - βγ / 2 ] , and 1 2 ⁡ [ 1 0 1 / 2 0 1 γ / 2 0 β - βγ / 2 α 0 - α / 2 ] , wherein α,β,γεΨ, |α|=1,|β|=1,|γ|=1, and contains M elements; traversing C 3*M 3 N types of codebooks, calculating a minimum distance D x , D x = min i ≠ j ⁢ ∑ diag ⁡ ( A i , j ′ × A i , j ) , for each codebook C x , wherein A i,j =(C x i )(C x i )′−(C x j )(C x j ) and C x i representing the i th matrix in the codebook C x ; and selecting a maximum codebook C opt corresponding to the minimum distance D x .