Method and device for a relay node to transmit a sounding reference signal to a base station in a wireless communication system
The present invention relates to a method for a relay node (RN) to transmit a sounding reference signal (SRS) to a base station in a wireless communication system. The method for SRS transmission includes: receiving the backhaul downlink subframe setting information from the base station; allocating backhaul uplink subframes on the basis of the received backhaul downlink subframe setting information; receiving uplink subframe setting information; receiving uplink subframe setting information for SRS transmission from the base station; receiving an indicator for triggering the SRS transmission from the base station; and, if a first uplink subframe from among the uplink subframes for the SRS transmission is the backhaul uplink subframe, transmitting the SRS from the first uplink subframe to the base station; or, if the first uplink subframe is not the backhaul uplink subframe is not the backhaul uplink subframe, not transmitting the SRS to the base station; or transmitting the SRS from a second uplink subframe, which is backhaul uplink subframe from among the uplink subframes for the SRS transmission and is subsequently the closest to the first uplink subframe, to the base station.
1. A method for transmitting an aperiodic sounding reference signal (A-SRS) to a base station (BS) by a relay node (RN) in a wireless communication system comprising:
receiving backhaul downlink (DL) subframe configuration information from the base station (BS);
allocating backhaul uplink (UL) subframes on the basis of the backhaul DL subframe configuration information;
receiving configuration information of UL subframes for A-SRS transmission from the BS;
receiving an indicator for triggering the A-SRS transmission from the base station (BS); and
if a first UL subframe among the UL subframes for the A-SRS transmission is allocated as the backhaul UL subframe, transmitting the A-SRS to the BS in the first UL subframe,
wherein, if the first UL subframe is not allocated as the backhaul UL subframe, the A-SRS is transmitted to the BS at a second UL subframe among the UL subframes for the A-SRS transmission,
wherein the second UL subframe is the closest UL subframe for the A-SRS transmission after the first UL subframe and is allocated as the backhaul UL subframe, and
wherein:
transmission power of the A-SRS transmitted in the second UL subframe is determined by power parameters for the A-SRS transmission configured for the first UL subframe if an uplink data channel is not transmitted between the first UL subframe and the second UL subframe, and
the transmission power of the A-SRS transmitted in the second UL subframe is determined by the power parameters for the uplink data channel if the uplink data channel is transmitted between the first UL subframe and the second UL subframe.
2. The method according to claim 1 , wherein allocating the backhaul UL subframes comprises:
excluding access DL subframes from backhaul DL subframes designated by the backhaul DL subframe configuration information; and
delaying the backhaul DL subframes by four subframes.
3. The method according to claim 2 , wherein the access DL subframes are subframes having indices # 0 , # 4 , # 5 , and # 9 .
4. The method according to claim 1 , wherein the configuration information of the UL subframes for the A-SRS transmission includes an offset value and a periodicity for transmission of the A-SRS.
5. The method according to claim 1 , wherein the A-SRS is transmitted using a predetermined hopping pattern in the second UL subframe regardless of a hopping pattern configured for the first UL subframe.
6. A relay node (RN) for transmitting an aperiodic sounding reference signal (A-SRS) in a wireless communication system comprising:
a reception module configured to receive backhaul downlink (DL) subframe configuration information from a base station (BS), to receive configuration information of UL subframes for A-SRS transmission from the BS, and to receive an indicator for triggering the A-SRS transmission from the BS;
a processor configured to allocate backhaul uplink (UL) subframes on the basis of the backhaul DL subframe configuration information; and
a transmission module configured to transmit the A-SRS to the BS in the first UL subframe if a first UL subframe among the UL subframes for the A-SRS transmission is allocated as the backhaul UL subframe,
wherein the transmission module is further configured to transmit the A-SRS to the BS at a second UL subframe among the UL subframes for the A-SRS transmission if the first UL subframe is not allocated as the backhaul UL subframe,
wherein the second UL subframe is the closest UL subframe for the A-SRS transmission after the first UL subframe and is allocated as the backhaul UL subframe, and
wherein:
transmission power of the A-SRS transmitted in the second UL subframe is determined by power parameters for the A-SRS transmission configured for the first UL subframe if an uplink data channel is not transmitted between the first UL subframe and the second UL subframe, and
the transmission power of the A-SRS transmitted in the second UL subframe is determined by the power parameters for the uplink data channel if the uplink data channel is transmitted between the first UL subframe and the second UL subframe.
7. The relay node (RN) according to claim 6 , wherein the processor is further configured to exclude access DL subframes from backhaul DL subframes designated by the backhaul DL subframe configuration information, and to allocate the backhaul UL subframes by delaying the backhaul DL subframes by four subframes.
8. The relay node (RN) according to claim 7 , wherein the access DL subframes are subframes having indices # 0 , # 4 , # 5 , and # 9 .
9. The relay node (RN) according to claim 6 , wherein the configuration information of the UL subframes for the A-SRS transmission includes an offset value and a periodicity for transmission of the A-SRS.
10. The relay node (RN) according to claim 6 , wherein the A-SRS is transmitted using a predetermined hopping pattern in the second UL subframe regardless of a hopping pattern configured for the first UL subframe.