Method for coordinated scheduling in wireless communication system and apparatus therefor

1. A method for transmitting signals for coordinated scheduling in a wireless communication system, the method performed by a base station and comprising:

transmitting, to a neighbor base station, information on a transmission scheme in a specific channel state information-interference measurement (CSI-IM) resource; and

receiving, from a mobile terminal served by the base station, a measurement result with respect to a downlink signal transmitted from the neighbor base station according to the transmission scheme in the specific CSI-IM resource,

wherein the transmission scheme is determined according to whether there is downlink data to be transmitted by the base station in a subframe to which the specific CSI-IM resource belongs and/or whether the mobile terminal configured with the specific CSI-IM resource is allocated a single CSI process or multiple CSI processes.

2. The method according to claim 1 , wherein

if there is downlink data to be transmitted by the base station in the subframe to which the specific CSI-IM resource belongs, the transmission scheme indicates that the base station transmits the downlink data or a dummy signal using the same precoding matrix index (PMI) as that of the downlink data in the specific CSI-IM resource, and

if there is no downlink data to be transmitted by the base station in the subframe to which the specific CSI-IM resource belongs, the transmission scheme indicates that the base station transmits no signal in the specific CSI-IM resource.

3. The method according to claim 1 , wherein

if there is downlink data to be transmitted by the base station in the subframe to which the specific CSI-IM resource belongs, the transmission scheme indicates that the base station transmits a dummy signal using a full-rank PMI in the specific CSI-IM resource, and

if there is no downlink data to be transmitted by the base station in the subframe to which the specific CSI-IM resource belongs, the transmission scheme indicates that the base station transmits no signal in the specific CSI-IM resource.

4. The method according to claim 1 , wherein

if there is downlink data to be transmitted after specific time, the transmission scheme indicates that the base station transmits a dummy signal using the same PMI as that of the downlink data to be transmitted after the specific time in the specific CSI-IM resource, and

if there is no downlink data to be transmitted after the specific time, the transmission scheme indicates that the base station transmits no signal in the specific CSI-IM resource.

5. The method according to claim 1 , wherein

if there is downlink data to be transmitted by the base station in the subframe to which the specific CSI-IM resource belongs, the transmission scheme indicates the base station transmits the downlink data or a dummy signal using the same PMI as that of the downlink data in the specific CSI-IM resource, and

if there is no downlink data to be transmitted by the base station in the subframe to which the specific CSI-IM resource belongs, the transmission scheme indicates that the base station transmits a dummy signal using a full-rank PMI in the specific CSI-IM resource.

6. The method according to claim 1 , wherein the transmission scheme indicates that the base station transmits a dummy signal using a full-rank PMI in the specific CSI-IM resource.

7. The method according to claim 1 , wherein the transmission scheme indicates the base station transmits no signal in the specific CSI-IM resource.

8. The method according to claim 1 , further comprising determining whether the neighbor base station transmits downlink signal during a specific interval based on the measurement result.

9. The method according to claim 8 , further comprising transmitting, to the neighbor base station, a message for requesting the neighbor base station to stop transmission of downlink signal during the specific interval upon determining that the neighbor base station does not transmit the downlink signal during the specific interval,

wherein the message includes a metric value of a gain according to stop of transmission of the neighbor base station or necessity for stop of transmission.

10. A method for transmitting signals by a base station for coordinated scheduling in a wireless communication system, the method performed by the base station and comprising:

receiving, from a neighbor base station, information on a transmission scheme in a specific CSI-IM resource; and

transmitting downlink signal in the specific CSI-IM resource according to the transmission scheme,

wherein the transmission scheme is determined according to whether there is downlink data to be transmitted by the base station in a subframe to which the specific CSI-IM resource belongs and/or whether the mobile terminal configured with the specific CSI-IM resource is allocated a single CSI process or multiple CSI processes.

11. A base station for coordinated scheduling in a wireless communication system, comprising:

a radio frequency (RF) unit; and

a processor configured to control the RF unit,

wherein the processor is configured to transmit, to a neighbor base station, information on a transmission scheme in a specific CSI-IM resource and to receive, from a UE served by the base station, a measurement result with respect to a downlink signal transmitted from the neighbor base station according to the transmission scheme in the specific CSI-IM resource,

wherein the transmission scheme is determined according to whether there is downlink data to be transmitted by the base station in a subframe to which the specific CSI-IM resource belongs and/or whether the mobile terminal configured with the specific CSI-IM resource is allocated a single CSI process or multiple CSI processes.