Patent ID: 8059733

Claim:
A method of operation of a downlink multi-user MIMO system comprising: receiving quantized feedback from a plurality of users; determining a subset of the plurality of users to transmit one or more signals to based on the received feedback; and determining a precoding matrix based on the received feedback from the plurality of users wherein the precoding matrix maximizes a sum-rate throughput for the subset of the plurality of users, said determining the precoding matrix with an iterative algorithm comprising: (a) initializing a precoding matrix G (0) ; (b) determining a precoding matrix G (k) at a k th iteration; (c) determining G (k+1) E HÎµD [(H*Ïˆ*AÏˆH) âˆ’1 H*Ïˆ*(1+i)A]| G (k) wherein H is a channel matrix of transmission channels to the plurality of users, E is an average power of the channel matrix, D is a generic Voronoi region, A = diag ( 1 A 1 , 1 A 2 , â€¦ â¢ , 1 A L ) , H=[H 1 T H 2 T . . . H L T ] T , Ïˆ=diag(T 1 , T 2 , . . . , T L ), i =diag(T 1 H 1 g 1 , T 2 H 2 g 2 , . . . , T 2 H L g L ), and T l = ( H l â¢ g l ) * â¢ âˆ‘ l - 1 â¢ , 1 â‰¤ l â‰¤ L iteratively repeating steps (b) and (c) until G converges.