Patent ID: 8285232

Claim:
A method of operating a mobile terminal which is compliant with a multi-rank beam forming (MRBF) system, comprising: generating feedback information for transmission in order for a remote transmitter to select a precoding matrix from a codebook of a plurality of matrices, wherein the plurality of matrices have a nested structure and are derived from a set of vector codebooks determined in accordance with the following expression: A ( v i 1 1 , v i 2 2 , v i 3 3 , … ⁢ ) = [ v i 1 1 , HH ⁡ ( v i 1 1 - e 1 M ) ⁡ [ 0 v i 2 2 ] , HH ⁡ ( v i 1 1 - e 1 M ) ⁡ [ 0 HH ⁡ ( v i 2 2 - e 1 M - 1 ) ⁡ [ 0 v i 3 3 ] ] , … ⁢ ] , wherein e 1 N =[1, 0, . . . , 0] T εC N , M is the number of transmit antennas, C N is an N-dimensional complex space, HH ⁡ ( w ) = { I - 2 ⁢ ww H  w  2 if w ≠ 0 I if w = 0 ⁢ and ⁢ ⁢ { v i j j ∈ C M - j + 1 } is a vector codebook and v i a is selected from a set V α where V 1 ={v i 1 εC M } i=1 N 1 , V 2 ={e 1 M-1 }, V 3 ={e 1 M-2 }, . . . .