MOBILE STATION DEVICE, BASE STATION DEVICE, MIMO SYSTEM, AND DATA TRANSMISSION METHOD

摘要

In order to improve data rates regardless of the magnitude of the spatial correlation between channels while also ensuring compatibility with LTE MIMO systems, a MIMO system for transmitting data while causing a base station device (eNode B) to switch between SU-MIMO transmission and ZF MU-MIMO transmission on the basis of feedback information from a mobile station device (UE) is configured so that: the mobile station device (UE) selects the PMI and RI corresponding to the Hermitian transposition of a channel matrix indicating propagation path characteristics, calculates the CQI from the PMI, and feeds back the PMI, RI, and CQI; and the base station device (eNode B) calculates a first data rate for SU-MIMO transmissions and a second data rate for ZF MU-MIMO transmission on the basis of the PMI that is fed back, and selects the transmission method corresponding to the higher of the first and second data rates.