Patent ID: 8116391

Claim:
A method of transmission between a transmitter and a plurality of receivers in a wireless multiple channel system where the transmitter transmits on at least n>1 antennas, the method comprising the steps of: each of the plurality of receivers identifying orthogonal modes of the respective channels between the transmitter and the respective receiver by estimating channel coefficients, storing the channel coefficients in a channel matrix and performing a transformation of the channel matrix; each receiver quantizing the orthogonal modes of the channel by selecting a codebook index of a set of codebook indices of orthogonal mode vectors; each receiver transmitting the codebook indices to the transmitter; and upon receiving the codebook indices from the receivers, the transmitter selecting a group of k receivers, where k is selected from 1 up to and including n, and transmitting to the group of k receivers using a stored channel modulation matrix that is selected based upon the codebook indices received by the transmitter, in which if the transmitter receives a codebook index corresponding to a full orthogonal mode matrix, the transmitter selects a stored channel modulation matrix based upon the received codebook index, selects a corresponding eigenmode distortion matrix and calculates estimated throughput for the receiver, and if the transmitter receives codebook indexes corresponding to orthogonal mode vectors, the transmitter maps the indices to a composite modulation index, uses the composite modulation index to select a corresponding stored channel modulation matrix, selects a corresponding distortion matrix and calculates estimated throughput for the k receivers.