Method for transmitting reference signal to antenna port in wireless access system

A user equipment (UE) for receiving a channel state information reference signal (CSI-RS) in a wireless access system, the UE comprising:

• a transceiver;
• and
• a processor configured to control the CSI-RS reception, the processor configured to receive a CSI-RS configuration information element to be used for 3 dimensional beamforming to receive the CSI-RS for each of antenna port groups based on the CSI-RS configuration information element, and to obtain a channel state information for the each of the antenna port groups based on the received CSI-RS, using the transceiver,
• wherein the CSI-RS configuration information element includes antenna set number parameters indicating the each of the antenna port groups and CSI-RS subframe configuration parameters indicating different transmission periods of the CSI-RS for the each of the antenna port groups,
• wherein the each of the antenna port groups has grouped for vertical beamforming and horizontal beamforming of the 3 dimensional beamforming, and
• wherein the each of the antenna port groups includes two or more antennas.

Method for transmitting a channel state information reference signal (CSI-RS) in a wireless access system, the method comprising:

• transmitting a CSI-RS configuration information element to be used for 3 dimensional beamforming, wherein the CSI-RS configuration information element includes antenna set number parameters indicating antenna port groups and CSI-RS subframe configuration parameters indicating different transmission periods of the CSI-RS for each of the antenna port groups;
• and
• transmitting the CSI-RS for the each of the antenna port groups based on the CSI-RS configuration information element;
• wherein the each of the antenna port groups has grouped for vertical beamforming and horizontal beamforming of the 3 dimensional beamforming, and
• wherein the each of the antenna port groups includes two or more antennas.

An evolved Node B (eNB) for transmitting a channel state information reference signal (CSI-RS) in a wireless access system, the eNB comprising:

• a transceiver;
• and
• a processor configured to control the CSI-RS transmission, the processor configured to transmit a CSI-RS configuration information element to be used for 3 dimensional beamforming, to transmit the CSI-RS for each of antenna port groups based on the CSI-RS configuration information element,
• wherein the CSI-RS configuration information element includes antenna set number parameters indicating the each of the antenna port groups and CSI-RS subframe configuration parameters indicating different transmission periods of the CSI-RS for the each of the antenna port groups,
• wherein the each of the antenna port groups has grouped for vertical beamforming and horizontal beamforming of the 3 dimensional beamforming, and
• wherein the each of the antenna port groups includes two or more antennas.