Method and apparatus for measuring inter-RU interference in order to perform space division duplex communication

1. A method for measuring inter-RU interference, by a UE having a plurality of radio units (RUs), in order to perform space division duplex communication, the method comprising:

acquiring first interference information indicating the strength of inter-RU interference after analog interference cancellation and second interference information indicating the strength of inter-RU interference before analog interference cancellation;

when the strength of interference indicated by the first interference information is greater than a first threshold value, determining that space division duplex communication between RUs cannot be performed;

when the strength of interference indicated by the first interference information is equal to or less than the first threshold value, determining that space division duplex communication between RUs can be performed,

periodically measuring inter-RU interference for performing the space division duplex communication between RUs when the strength of interference indicated by the second interference information is greater than a second threshold value; and

not periodically measuring inter-RU interference for performing the space division duplex communication between RUs when the strength of interference indicated by the second interference information is equal to or less than the second threshold value,

wherein the RUs correspond to antenna ports.

2. The method of claim 1 , wherein the space division duplex communication between RUs is communication through which one RU receives a signal and another RU transmits a signal or communication through which one RU transmits a signal and another RU receives a signal.

3. The method of claim 1 , further comprising transmitting the first interference information and the second interference information to an eNB.

4. The method of claim 1 , further comprising:

receiving the first threshold value and the second threshold value from an eNB; and

receiving information on allocation of resources for periodically measuring the inter-RU interference from the eNB,

wherein the first threshold value and the second threshold value are broadcast or transmitted through a radio resource control (RRC) message.

5. The method of claim 4 , further comprising transmitting information representing whether the strength of interference indicated by the first interference information is greater than the first threshold value and whether the strength of interference indicated by the second interference information is greater than the second threshold value to the eNB.

6. The method of claim 1 , further comprising:

transmitting, to an eNB, information about an RU group that transmits a reference signal for periodically measuring the inter-RU interference;

transmitting the strength of inter-RU long-term interference included in the RU group information to the eNB if the strength of the inter-RU long-term interference included in the RU group information is equal to or less than the second threshold value; and

not transmitting the strength of the inter-RU long-term interference included in the RU group information to the eNB if the strength of the inter-RU long-term interference included in the RU group information is greater than the second threshold value.

7. The method of claim 6 , wherein space division duplex communication between RUs included in the RU group information is performed if the strength of the inter-RU long-term interference included in the RU group information is transmitted to the eNB, and space division duplex communication between RUs included in the RU group information is not performed if the strength of the inter-RU long-term interference included in the RU group information is not transmitted to the eNB.

8. The method of claim 6 , wherein, if the strength of the inter-RU long-term interference included in the RU group information is transmitted to the eNB, a modulation scheme, a channel code rate and resource allocation for transmitting signals using an RU included in the RU group information are determined on the basis of the strength of the inter-RU long-term interference included in the RU group information.

9. The method of claim 6 , wherein the reference signal for periodically measuring the inter-RU interference is transmitted from some RUs, a reference signal for performing channel estimation with respect to the eNB is received by some other RUs, and the reference signal for periodically measuring the inter-RU interference and the reference signal for performing channel estimation with respect to the eNB are orthogonal to each other.

10. A UE for measuring inter-RU interference in order to perform space division duplex communication, the UE comprising:

a radio frequency (RF) unit configured to transmit and receive RF signals; and

a processor connected to the RF unit,

wherein the processor is configured:

to acquire first interference information indicating the strength of inter-RU interference after analog interference cancellation and second interference information indicating the strength of inter-RU interference before analog interference cancellation;

when the strength of interference indicated by the first interference information is greater than a first threshold value, to determine that space division duplex communication between RUs cannot be performed;

when the strength of interference indicated by the first interference information is equal to or less than the first threshold value, to determine that space division duplex communication between RUs can be performed,

to periodically measure inter-RU interference for performing the space division duplex communication between RUs when the strength of interference indicated by the second interference information is greater than a second threshold value; and

not to periodically measure inter-RU interference for performing the space division duplex communication between RUs when the strength of interference indicated by the second interference information is equal to or less than the second threshold value,

wherein the RUs correspond to antenna ports, and the UE has a plurality of RUs.

11. The UE of claim 10 , wherein the space division duplex communication between RUs is communication through which one RU receives a signal and another RU transmits a signal or communication through which one RU transmits a signal and another RU receives a signal.

12. The UE of claim 10 , wherein the processor transmits the first interference information and the second interference information to an eNB.

13. The UE of claim 10 , wherein the processor receives the first threshold value and the second threshold value from an eNB and receives information on allocation of resources for periodically measuring the inter-RU interference from the eNB,

wherein the first threshold value and the second threshold value are broadcast or transmitted through a radio resource control (RRC) message.

14. The UE of claim 13 , wherein the processor transmits information representing whether the strength of interference indicated by the first interference information is greater than the first threshold value and whether the strength of interference indicated by the second interference information is greater than the second threshold value to the eNB.

15. The UE of claim 10 , wherein the processor transmits, to an eNB, information about an RU group that transmits a reference signal for periodically measuring the inter-RU interference, transmits the strength of inter-RU long-term interference included in the RU group information to the eNB if the strength of the inter-RU long-term interference included in the RU group information is equal to or less than the second threshold value, and does not transmit the strength of the inter-RU long-term interference included in the RU group information to the eNB if the strength of the inter-RU long-term interference included in the RU group information is greater than the second threshold value.

16. The UE of claim 15 , wherein space division duplex communication between RUs included in the RU group information is performed if the strength of the inter-RU long-term interference included in the RU group information is transmitted to the eNB, and space division duplex communication between RUs included in the RU group information is not performed if the strength of the inter-RU long-term interference included in the RU group information is not transmitted to the eNB.

17. The UE of claim 15 , wherein, if the strength of the inter-RU long-term interference included in the RU group information is transmitted to the eNB, a modulation scheme, a channel code rate and resource allocation for transmitting signals using an RU included in the RU group information are determined on the basis of the strength of the inter-RU long-term interference included in the RU group information.

18. The UE of claim 15 , wherein the reference signal for periodically measuring the inter-RU interference is transmitted from some RUs, a reference signal for performing channel estimation with respect to the eNB is received by some other RUs, and the reference signal for periodically measuring the inter-RU interference and the reference signal for performing channel estimation with respect to the eNB are orthogonal to each other.