CHANNEL STATE FEEDBACK FOR MULTI-CELL MIMO

摘要

A method is disclosed which is intended for use in multiple-input multiple-output (MIMO) wireless communication systems of the kind which have a plurality of adjacent cells, each containing one or more base stations operable to transmit signals to, and receive signals transmitted from, one or more user equipments The user equipments are operable to feed back to the relevant base stat?on(s) channel state information relating to channel(s) between the relevant base stat?on(s) and the user equipments, and the base stations are operable to adapt signals for transmission to user equipments, based on the fed back channel state information The proposed method involves identifying uplink resources for a user equipment-initiated channel state message, the user equipment judging a need for a user equipment- initiated channel state message based on information not available to the network, and the user equipment sending the user equipment-initiated channel state message to the network using the identified uplink resources The user equipment-initiated channel state message may be a CSI report or a request to change a CSI reporting rate, reporting rate or reporting mode.