RADIO BASE STATION, USER TERMINAL AND RADIO COMMUNICATION METHOD

摘要

The present invention is designed to reduce the overhead of reference signals for measuring CSI in high-order MIMO multiplexing technique. A radio base station is used in a radio communications system of a frequency division duplexing (FDD) scheme, and has a receiving section that receives reference signals for measuring time division duplex (TDD) channel state information, transmitted from a plurality of antennas provided in a user terminal, a measurement section that measures the channel state information, in a plurality of receiving antennas, by using the reference signals, a generation/selection section that generates an optimal precoding vector from the channel state information measured in each receiving antenna, or selects the optimal precoding vector from a set of precoding vectors that is defined in advance, and a transmission section that transmits a physical downlink shared channel, in MIMO multiplexing transmission, by using the precoding vector selected in the generation/selection section.

主权项

1. A radio base station that is used in a radio communications system of a frequency division duplexing (FDD) scheme, the radio base station comprising:
a receiving section that receives reference signals for measuring time division duplex (TDD) channel state information, transmitted from a plurality of antennas provided in a user terminal; a measurement section that measures the channel state information, in a plurality of receiving antennas, by using the reference signals; a generation/selection section that generates an optimal precoding vector from the channel state information measured in each receiving antenna, or selects the optimal precoding vector from a set of precoding vectors that is defined in advance; and a transmission section that transmits a physical downlink shared channel, in MIMO multiplexing transmission, by using the precoding vector selected in the generation/selection section.