REFERENCE SIGNAL TRANSMISSION METHOD FOR DOWNLINK MULTIPLE INPUT MULTIPLE OUTPUT SYSTEM

摘要

PURPOSE: A reference signal transmission method for downlink multiple input multiple output system is provided to effectively transmit a reference signal in environment which LTE UE(User Equipment) and LTE-A(LTE-Advanced) UE coexists. CONSTITUTION: A first UE recognizes four transmission antennas among eight transmission antennas. A second UE recognizes the eight transmission antenna. In the base station, one reference signal transmission mode is selected between a plurality of reference signal transmission modes according to rank(S601). In the base station, the reference signal is transmitted according to the selected reference signal transmission mode(S602). The second reference signal transmission mode uses a pre-coded demodulation-common reference signal as the reference signal toward the transmission eight antennas.