RADIO COMMUNICATION SYSTEM, RADIO BASE STATION AND USER DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce at least one of the transmission overhead of a reference signal and the transmission overhead of feedback information in a 3D-MIMO radio communication system.SOLUTION: A radio communication system includes a radio base station having a plurality of two-dimensionally disposed antenna elements and a user device for radio communicating with the radio base station. The radio base station transmits a reference signal for propagation path measurement, with a plurality of different configurations, using a part or the whole of the antenna elements. Based on the reference signal, the user device feeds back the whole or any of the propagation path information in a horizontal direction, a vertical direction and between polarized waves, to the radio base station.