摘要 |
The present invention relates to a Multi-Input Multi-Output (MIMO) communication system and more particularly, to a method for precoding matrix index (PMI) restriction/recommendation in a multi-cell wireless communication system. A method of codebook based precoding matrix index (PMI) feedback considering legacy mobile stations in a multi-cell wireless communication system comprises measuring a channel from at least one neighboring base station generating interference with a signal received from a serving base station; determining a first PMI in which the interference is maximized from PMIs included in a first codebook, wherein the first PMI is determined based on the measured channel; determining a first PMI group including PMIs having high correlation to the first PMI from the PMIs included in the first codebook; determining a second PMI in which the interference is maximized from PMIs included in a second codebook, where in the second codebook is for the legacy mobile stations; determining a second PMI group including PMIs having high correlation to the second PMI from the PMIs included in the second codebook; and transmitting feedback information including the first PMI, a first subset bit indicating the first PMI group, the second PMI and a second subset bit indicating the second PMI group to the serving base station. |