METHOD AND APPARATUS FOR PERFORMING MULTIPLE-INPUT MULTIPLE-OUTPUT WIRELESS COMMUNICATIONS

摘要

A method and an apparatus for performing multiple-input multiple-output (MIMO) wireless communications are disclosed. A Node-B may receive an index to a pre-coding matrix in a single user MIMO (SU-MIMO) pre-coding codebook from wireless transmit/receive units (WTRUs) and adaptively perform one of SU-MIMO or multi-user MIMO (MU-MIMO) based on a predetermined criterion. Channel information for performing MU-MIMO may be obtained based on the pre-coding matrix of the SU-MIMO pre-coding codebook. A rank requested by the WTRU may be overridden if the unitary MU-MIMO codebook is a subset of the SU-MIMO pre-coding codebook. If not, a MU-MIMO pre-coding matrix with a largest correlation to the pre-coding matrix may be selected. A WTRU may send a pre-coding matrix for transmission to the WTRU along with a preferred interference matrix. A WTRU may send rank information and multiple right singular vectors for MU-MIMO.