Method and apparatus for measuring downlink interference in OFDM mobile communication system
A method and apparatus for efficiently measuring downlink interference in a Distributed Antenna System (DAS)-based Long Term Evolution Advanced (LTE-A) system with a plurality antennas distributed within the service area of each evolved Node B (eNB), through the use of a Channel Status Information Reference Signal (CSI-RS) method and a muting method, is provided.
1. An interference measurement method of a base station in a wireless communication system, the method comprising:
identifying a channel status information reference signal (CSI-RS) for channel measurement;
identifying zero-power CSI-RS for interference measurement;
transmitting, to a user equipment (UE), CSI-RS configuration information for channel measurement, zero-power CSI-RS configuration information for interference measurement and feedback configuration information;
transmitting, to the UE, a CSI-RS; and
receiving, from the UE, channel state information generated based on the CSI-RS configuration information, the zero-power CSI-RS configuration information and the feedback configuration information,
wherein the zero-power CSI-RS configuration information comprises resource information and a period of subframes for a zero-power CSI-RS, the resource information indicating a predefined pattern from a set of predefined patterns, and
wherein in case that a part of a resource for the zero-power CSI-RS is overlapped with a resource for the CSI-RS, the part of the resource for the zero-power CSI-RS is used for transmitting the CSI-RS.
2. The method of claim 1 , wherein the CSI-RS configuration information comprises resource information and a period of subframes for the CSI-RS.
3. The method of claim 1 , wherein the resource information in the zero-power CSI-RS configuration information indicates two resource element (RE) pairs,
wherein each RE pair is two consecutive REs.
4. The method of claim 3 wherein each RE pair is two consecutive REs having two consecutive Orthogonal Frequency Division Multiplexing (OFDM) symbols in a time domain and one subcarrier in a frequency domain.
5. The method of claim 1 , wherein the CSI-RS configuration information and the zero-power CSI-RS configuration information are transmitted via a higher layer signaling.
6. An interference measurement method of a user equipment (UE) in a wireless communication system, the method comprising:
receiving, from a base station, channel status information reference signal (CSI-RS) configuration information for channel measurement and zero-power CSI-RS configuration information for interference measurement and feedback configuration information;
receiving, from the base station, a CSI-RS;
obtaining channel state information based on the CSI-RS configuration information and the zero-power CSI-RS configuration information; and
transmitting the channel state information based on the feedback configuration information to the base station,
wherein the zero-power CSI-RS configuration information comprises resource information and a period of subframes for a zero power CSI-RS, the resource information indicating a predefined pattern from a set of predefined patterns, and
wherein in case that a part of a resource for the zero-power CSI-RS is overlapped with a resource for the CSI-RS, the part of the resource for the zero-power CSI-RS is used for transmitting the CSI-RS.
7. The method of claim 6 , wherein the CSI-RS configuration information comprises resource information and a period of subframes for the CSI-RS.
8. The method of claims 6 , wherein the resource information in the zero-power CSI-RS configuration information indicates two resource element (RE) pairs,
wherein each RE pair is two consecutive REs.
9. The method of claim 8 , wherein each RE pair is two consecutive REs having two consecutive Orthogonal Frequency Division Multiplexing (OFDM) symbols in a time domain and one subcarrier in a frequency domain.
10. The method of claim 6 , wherein the CSI-RS configuration information and the zero-power CSI-RS configuration information are received via a higher layer signaling.
11. A base station for measuring interference in a wireless communication system, the base station comprising:
a transceiver configured to transmit and receive a signal; and
a controller configured to:
identify channel status information reference signal (CSI-RS) for channel measurement,
identify zero-power CSI-RS for interference measurement,
transmit, to a user equipment (UE), CSI-RS configuration information for channel measurement, zero-power CSI-RS configuration information for interference measurement and feedback configuration information,
transmit, to the UE, a CSI-RS, and
receive, from the UE, channel state information generated based on the CSI-RS configuration information, the zero-power CSI-RS configuration information and the feedback configuration information,
wherein the zero-power CSI-RS configuration information comprises resource information and a period of subframes for a zero-power CSI-RS, the resource information indicating a predefined pattern from a set of predefined patterns, and
wherein in case that a part of a resource for the zero-power CSI-RS is overlapped with a resource for CSI-RS, the part of the resource for the zero-power CSI-RS is used for transmitting the CSI-RS.
12. The base station of claim 11 , wherein the CSI-RS configuration information comprises resource information and a period of subframes for the CSI-RS.
13. The base station of claim 11 , wherein the resource information in the zero-power CSI-RS configuration information indicates two resource element (RE) pairs,
wherein each RE pair is two consecutive REs.
14. The base station of claim 13 , wherein each RE pair is two consecutive REs having two consecutive Orthogonal Frequency Division Multiplexing (OFDM) symbols in a time domain and one subcarrier in a frequency domain.
15. The base station of claim 11 , wherein the CSI-RS configuration information and the zero-power CSI-RS configuration information are transmitted via a higher layer signaling.
16. A user equipment (UE) for measuring interference in a wireless communication system, the UE comprising:
a transceiver configured to transmit and receive a signal; and
a controller configured to:
receive, from a base station, channel status information reference signal (CSI-RS) configuration information for channel measurement, zero-power CSI-RS configuration information for interference measurement and feedback configuration information,
receive, from the base station, CSI-RS,
obtain channel state information based on the CSI-RS configuration information and the zero-power CSI-RS configuration information, and
transmit the channel state information to the base station based on the feedback configuration information,
wherein the zero-power CSI-RS configuration information comprises resource information and a period of subframes for a zero power CSI-RS, the resource information indicating a predefined pattern from a set of predefined patterns, and
wherein in case that a part of a resource for the zero-power CSI-RS is overlapped with a resource for the CSI-RS, the part of the resource for the zero-power CSI-RS is used for transmitting the CSI-RS.
17. The UE of claim 16 , wherein the CSI-RS configuration information comprises resource information and a period of subframes for the CSI-RS.
18. The UE of claim 16 , wherein the resource information in the zero-power CSI-RS configuration information indicates two resource element (RE) pairs,
wherein each RE pair is two consecutive REs.
19. The UE of claim 18 , wherein each RE pair is two consecutive REs having two consecutive Orthogonal Frequency Division Multiplexing (OFDM) symbols in a time domain and one subcarrier in a frequency domain.
20. The UE of claim 16 , wherein the CSI-RS configuration information and the zero-power CSI-RS configuration information are received via a higher layer signaling.