Method and apparatus for transmitting reference signal in multi-node system

1. A method of transmitting a reference signal in a multi-node system including a plurality of nodes and a base station for controlling the plurality of nodes, the method comprising:

transmitting node information to a user equipment;

transmitting the reference signal to the user equipment from at least one node among the plurality of nodes on the basis of the node information,

wherein the node information includes information capable of identifying the reference signal transmitted from the at least one node,

wherein the node information includes antenna port information or reference signal configuration information used by each of the plurality of nodes,

wherein each of the plurality of nodes transmits a different reference signal,

wherein the node information is generated by using new seed number independently from a cell identification (ID) such that the node information and the cell ID are independently configured, and

wherein a format of node information is different from a format of the cell ID; and

receiving feedback information from the user equipment via at least one node among the plurality of nodes,

wherein the feedback information includes the antenna port information or the reference signal configuration information.

2. The method of claim 1 , wherein when the cell ID used by the base station consists of a cell ID group and an ID included in the cell ID group, a node ID of each of the plurality of nodes includes the same bit as the cell ID group.

3. The method of claim 1 , wherein when the cell ID used by the base station consists of a cell ID group and an ID included in the cell ID group, a node ID of each of the plurality of nodes includes the same bit of the ID included in the cell ID group.

4. The method of claim 1 , wherein each of the plurality of nodes transmits a reference signal corresponding to a different antenna port.

5. The method of claim 1 , wherein each of the plurality of nodes transmits a reference signal corresponding to a different reference signal configuration number.

6. The method of claim 1 , wherein each of the plurality of nodes transmits a reference signal corresponding to the same cell ID, the same antenna port, and the same reference signal configuration number, and the reference signal is transmitted by using a different time, frequency, or code.

7. The method of claim 1 , wherein each of the plurality of nodes is an antenna or antenna group coupled to the base station in a wired fashion.

8. An apparatus for transmitting a reference signal, the apparatus comprising:

a radio frequency (RF) unit for transmitting and receiving a radio signal;

a processor coupled to the RF unit, wherein the RF unit includes a plurality of nodes,

wherein the processor transmits information to a user equipment and transmits the reference signal to the user equipment from at least one node among the plurality of nodes on the basis of the node information, and

wherein the node information includes information capable of identifying the reference signal transmitted from the at least one node,

wherein the node information includes antenna port information or reference signal configuration information used by each of the plurality of nodes,

wherein each of the plurality of nodes transmits a different reference signal,

wherein the node information is generated by using new seed number independently from a cell identification (ID) such that the node information and the cell ID are independently configured,

wherein a format of node information is different from a format of the cell ID,

wherein the processor further receives feedback information from the user equipment via at least one node among the plurality of nodes, and

wherein the feedback information includes the antenna port information or the reference signal configuration information.