Patent ID: 8457233

Claim:
A base station for a single user multiple input multiple output (MIMO) communication system, the base station comprising: a memory where a codebook including codeword matrices C 1,1 , C 2,1 , C 3,1 , C 4,1 , C 5,1 , C 6,1 , C 7,1 , C 8,1 , C 9,1 , C 10,1 , C 11,1 , C 12,1 , C 13,1 , C 14,1 , C 15,1 , and C 16,1 is stored; and a precoder to precode a data stream to be transmitted using the codebook, wherein the codeword matrices are defined by the following table: C 1,1 = C 2,1 = C 3,1 = C 4,1 = 0.5000 −0.5000 −0.5000 0.5000 −0.5000 −0.5000 0.5000 0 − 0.5000i 0.5000 0.5000 0.5000 0.5000 −0.5000 0.5000 −0.5000 0 − 0.5000i C 5,1 = C 6,1 = C 7,1 = C 8,1 = −0.5000 −0.5000 0.5000 0.5000 0 − 0.5000i 0 + 0.5000i 0.5000 0 + 0.5000i 0.5000 0.5000 0.5000 0.5000 0 + 0.5000i 0 − 0.5000i 0.5000 0 + 0.5000i C 9,1 = C 10,1 = C 11,1 = C 12,1 = 0.5000 0.5000 0.5000 0.5000 0.5000 0 + 0.5000i −0.5000 0 − 0.5000i 0.5000 −0.5000 0.5000 −0.5000 −0.5000 0 + 0.5000i 0.5000 0 − 0.5000i C 13,1 = C 14,1 = C 15,1 = C 16,1 = 0.5000 0.5000 0.5000 0.5000 0.3536 + 0.3536i −0.3536 + −0.3536 − 0.3536 − 0.3536i 0.3536i 0.3536i 0 + 0.5000i 0 − 0.5000i 0 + 0.5000i 0 − 0.5000i −0.3536 + 0.3536 + 0.3536i 0.3536 − 0.3536i −0.3536 − 0.3536i 0.3536i.