Technique for transmitting and receiving downlink reference signals

A method of receiving a downlink reference signal in a user equipment in a multiple input multiple output (MIMO) wireless communication system, the method comprising:

• receiving the downlink reference signal for demodulation of a downlink data signal;
• and
• receiving a downlink control signal for the user equipment,
• wherein:
• the downlink control signal includes information indicating an antenna port of a base station (BS) on which the downlink reference signal is transmitted among a plurality of BS antenna ports, when the downlink reference signal is transmitted by the BS via only one transmission layer;
• and
• the downlink reference signal is transmitted on predetermined antenna ports among the plurality of BS antenna ports, when the downlink reference signal is transmitted by the BS via two or more transmission layers, and
• wherein each of the at least one transmission layer is a signal path that corresponds to each of the plurality of BS antenna ports.

A base station in a multiple input multiple output (MIMO) wireless communication system, the base station comprising:

• a processor configured to:
• provide a downlink reference signal for a demodulation of a downlink data signal, and
• provide a downlink control signal for each of a user equipment;
• and
• a transmitting module configured to transmit the downlink reference signal and the downlink control signal via at least one transmission layer to the user equipment,
• wherein:
• the downlink control signal includes information indicating an antenna point on which the downlink reference signal is transmitted among a plurality of antenna ports, when the downlink reference signal t is transmitted via only one transmission layer;
• and
• the downlink reference signal is transmitted on predefined antenna ports among the plurality of antenna ports, when the downlink reference signal is transmitted via two or more transmission layers, and
• wherein each of the at least one transmission layer is a signal path that corresponds to each of the plurality of antenna ports.

A user equipment in a multiple input multiple output (MIMO) wireless communication system, the user equipment comprising:

• a receiving module configured to receive a downlink reference signal for a demodulation of a downlink data signal and a downlink control signal;
• and
• a processor configured to process the downlink reference signal according to information included in the downlink control signal,
• wherein:
• the downlink control signal includes information indicating an antenna port of a base station (BS) on which the downlink reference signal is transmitted among a plurality of BS antenna ports, when the downlink reference signal is transmitted by the BS via only one transmission layer;
• and
• the downlink reference signal is transmitted by the BS on predefined antenna ports among the plurality of BS antenna ports, when the downlink reference signal is transmitted by the BS via two or more transmission layers,
• wherein each of the at least one transmission layer is a signal path that corresponds to each of the plurality of BS antenna ports.