Transmission of uplink sounding reference signal

Abstract

Provided are methods for transmission of a sounding reference signal (SRS) being independent of or separated from an uplink channel. The method may include receiving UE-specific configuration information including an uplink reference signal identity from the first transmission/reception point, determining the second transmission/reception point indicated by the uplink reference signal identity included in the received UE-specific configuration information as an uplink channel reception entity, transmitting the uplink channel to the determined second transmission/reception point, using the uplink reference signal identity, generating an SRS, using the physical cell identity of the first transmission/reception point, determining the first transmission/reception point as an SRS reception entity, and transmitting the generated SRS to the determined first transmission/reception point indicated by the physical cell identity.

What is claimed is: 
     
       1. A method of transmitting an uplink sounding reference signal (SRS) in user equipment (UE) in a coordinated multi-point transmission/reception system (CoMP system), the method comprising:
 receiving, by the user equipment, UE-specific configuration information including an uplink reference signal identity associated with an uplink channel, from a first transmission/reception point of a plurality of different transmission/reception points, wherein the uplink reference signal identity is independent of a physical cell identity of the first transmission/reception point and indicates a second transmission/reception point as a reception entity of the uplink channel; and 
 performing, by the user equipment, an independent transmission of the uplink channel and an SRS to different transmission/reception points, using the uplink reference signal identity or the physical cell identity according to a type of an uplink transmission, 
 wherein when the type of the uplink transmission is an uplink channel transmission, 
 the performing includes:
 obtaining the uplink reference signal identity from the received UE-specific configuration information; 
 determining the second transmission/reception point indicated by the uplink reference signal identity, as an uplink channel reception entity, wherein the second transmission/reception point is different from the first transmission/reception point; and 
 transmitting, by the user equipment, the uplink channel to the determined second transmission/reception point, using the uplink reference signal identity; 
 
 wherein when the type of the uplink transmission is an SRS transmission, 
 the performing includes:
 generating, by the user equipment, an SRS independent of the uplink channel, using the physical cell identity of the first transmission/reception point; 
 determining the first transmission/reception point which has transmitted the UE-specific configuration information to the user equipment, as an SRS reception entity; and 
 transmitting, by the user equipment, the generated SRS to the determined first transmission/reception point; 
 
 wherein: 
 the SRS includes at least one of a periodic SRS and an aperiodic SRS, 
 the generating an SRS includes generating both the periodic SRS and the aperiodic SRS using the physical cell identity of the first transmission/reception point, and 
 the transmitting the generated SRS includes transmitting one of the periodic SRS and the aperiodic SRS to the first transmission/reception point indicated by the physical cell identity; 
 wherein the uplink channel is at least one of a physical uplink shared channel and a physical uplink control channel; and 
 wherein the receiving UE-specific configuration information includes receiving, from the first transmission/reception point, the UE-specific configuration information including the uplink reference signal identity, either through a UE-specific parameter, or dynamically through at least one of a physical downlink control channel (PDCCH) and an enhanced physical downlink control channel (EPDCCH). 
 
     
     
       2. The method of  claim 1 , wherein:
 the generating an SRS includes generating one of the periodic SRS and the aperiodic SRS using the physical cell identity of the first transmission/reception point, and the other SRS using the uplink reference signal identity; and   the transmitting the generated SRS includes transmitting one of the periodic SRS and the aperiodic SRS to the first transmission/reception point, and the other SRS to the second transmission/reception point indicated by the uplink reference signal identity.   
     
     
       3. User equipment in a coordinated multi-point transmission/reception system (CoMP system), the user equipment comprising:
 a receiver configured to receive UE-specific configuration information including an uplink reference signal identity associated with an uplink channel, from a first transmission/reception point of a plurality of different transmission/reception points, wherein the uplink reference signal identity is independent of a physical cell identity of the first transmission/reception point and indicates a second transmission/reception point as a reception entity of the uplink channel; and   a transmitter configured to perform an independent transmission of the uplink channel and a sounding reference signal (SRS) to different transmission/reception points, using the uplink reference signal identity or the physical cell identity according to whether a type of an uplink transmission is an uplink channel transmission or an SRS transmission,   wherein the transmitter includes:
 an uplink channel transmission unit configured to obtain the uplink reference signal identity from the received UE-specific configuration information; to determine the second transmission/reception point indicated by the uplink reference signal identity, as an uplink channel reception entity; and to transmit the uplink channel to the determined second transmission/reception point, using the uplink reference signal identity, wherein the second transmission/reception point is different from the first transmission/reception point; 
 an SRS generating unit configured to generate an SRS being independent of the uplink channel, using the physical cell identity of the first transmission/reception point; and 
 an SRS transmitting unit configured to determine the first transmission/reception point which has transmitted the UE-specific configuration information to the user equipment, as an SRS reception entity, and to transmit the generated SRS to the determined first transmission/reception point; 
   wherein:   the SRS includes at least one of a periodic SRS and an aperiodic SRS,   the SRS generating unit is configured to generate both the periodic SRS and the aperiodic SRS using the physical cell identity of the first transmission/reception point, and   the SRS transmitting unit is configured to transmit one of the periodic SRS and the aperiodic SRS to the first transmission/reception point indicated by the physical cell identity;   wherein the uplink channel is at least one of a physical uplink shared channel and a physical uplink control channel; and   wherein the receiver is configured to receive, from the first transmission/reception point, the UE-specific configuration information including the uplink reference signal identity, either through a UE-specific parameter, or dynamically through at least one of a physical downlink control channel (PDCCH) and an enhanced physical downlink control channel (EPDCCH).   
     
     
       4. The user equipment of  claim 3 , wherein:
 the SRS generating unit is configured to generate one of the periodic SRS and the aperiodic SRS using the physical cell identity of the first transmission/reception point, and to generate the other SRS using the uplink reference signal identity; and   the SRS transmitting unit is configured to transmit one of the periodic SRS and the aperiodic SRS to the first transmission/reception point, and to transmit the other SRS to the second transmission/reception point indicated by the uplink reference signal identity.   
     
     
       5. A method of transmitting an uplink sounding reference signal (SRS) in user equipment (UE) in a coordinated multi-point transmission/reception system (CoMP system), the method comprising:
 receiving, by the user equipment, UE-specific configuration information including a sounding reference signal (SRS) identity from a first transmission/reception point of a plurality of different transmission/reception points, wherein the SRS identity is independently determined to be distinguished from an uplink reference signal identity for an uplink channel and indicates a second transmission/reception point as a reception entity of an SRS; and   performing, by the user equipment, an independent transmission of the uplink channel and the SRS to different transmission/reception points, using the uplink reference signal identity or the SRS identity according to a type of an uplink transmission,   wherein when the type of the uplink transmission is an SRS transmission,   the performing includes:
 obtaining, by the user equipment, the SRS identity from the received UE-specific configuration information; 
 generating, by the user equipment, an SRS using the SRS identity; 
 determining the second transmission/reception point UE-specifically indicated by the SRS identity, as an SRS reception entity, wherein the second transmission/reception point is different from the first transmission/reception point which has transmitted the UE-specific configuration information to the user equipment; and 
 transmitting, by the user equipment, the generated SRS to the determined second transmission/reception point; 
   wherein the SRS includes at least one of a periodic SRS and an aperiodic SRS;   wherein the generating an SRS includes generating both the periodic SRS and the aperiodic SRS using the SRS identity; and   wherein the receiving UE-specific configuration information includes receiving, from the first transmission/reception point, the UE-specific configuration information including the SRS identity, either through a UE-specific parameter, or dynamically through at least one of a physical downlink control channel (PDCCH) and an enhanced physical downlink control channel (EPDCCH).   
     
     
       6. The method of  claim 5 , wherein:
 the UE-specific configuration information includes a same reference signal identity for the periodic SRS and the aperiodic SRS.   
     
     
       7. The method of  claim 5 , wherein:
 the UE-specific configuration information includes a different reference signal identity for each of the periodic SRS and the aperiodic SRS.   
     
     
       8. The method of  claim 5 , wherein:
 the generating an SRS includes generating one of the periodic SRS and the aperiodic SRS using the SRS identity, and the other SRS using a physical cell identity of the first transmission/reception point; and   the transmitting the generated SRS includes transmitting one of the periodic SRS and the aperiodic SRS to the second transmission/reception point indicated by the SRS identity, and the other SRS to the first transmission/reception point.   
     
     
       9. A method of transmitting an uplink sounding reference signal (SRS) in user equipment (UE) in a coordinated multi-point transmission/reception system (CoMP system) including a first transmission/reception point and a second transmission/reception point, the method comprising:
 receiving, by the user equipment, UE-specific configuration information including an uplink reference signal identity which is an independent identity distinguished from a physical cell identity of the first transmission/reception point and indicates the second transmission/reception point as a reception entity of the uplink channel from the first transmission/reception point through either a UE-specific parameter or dynamically through at least one of a physical downlink control channel (PDCCH) and an enhanced physical downlink control channel (EPDCCH);   determining, by the user equipment, the second transmission/reception point indicated by the uplink reference signal identity included in the received UE-specific configuration information as an uplink channel reception entity, and transmitting the uplink channel to the determined second transmission/reception point, using the uplink reference signal identity; and   generating, by the user equipment, both a periodic SRS and an aperiodic SRS, using the physical cell identity of the first transmission/reception point, determining the first transmission/reception point as an SRS reception entity, and transmitting the generated periodic SRS and aperiodic SRS to the determined first transmission/reception point indicated by the physical cell identity through the uplink channels.   
     
     
       10. The method of claim 9, wherein the second transmission/reception point is different from the first transmission/reception point. 
     
     
       11. The method of the claim 9, wherein the uplink channel includes a PUCCH and a PUSCH. 
     
     
       12. User equipment in a coordinated multi-point transmission/reception system (CoMP system) including a first transmission/reception point and a second transmission/reception point, the user equipment comprising:
 a receiver configured to receive UE-specific configuration information including an uplink reference signal identity which is an independent identify distinguished from of a physical cell identity of the first transmission/reception point and indicates the second transmission/reception point as a reception entity of the uplink channel from the first transmission/reception point through either a UE-specific parameter or dynamically through at least one of a physical downlink control channel (PDCCH) and an enhanced physical downlink control channel (EPDCCH); and   a transmitter configured to determine the second transmission/reception point indicated by the uplink reference signal identity included in the received UE-specific configuration information as an uplink channel reception entity and transmit the uplink channel to the determined second transmission/reception point, using the uplink reference signal identity, and generate both a periodic SRS and an aperiodic SRS, using the physical cell identity of the first transmission/reception point, determine the first transmission/reception point as an SRS reception entity and transmit the generated periodic SRS and aperiodic SRS to the determined first transmission/reception point indicated by the physical cell identity through the uplink channel.   
     
     
       13. The user equipment of claim 12, wherein the second transmission/reception point is different from the first transmission/reception point. 
     
     
       14. The user equipment of claim 13, wherein the uplink channel includes a PUCCH and a PUSCH. 
     
     
       15. A method of transmitting an uplink sounding reference signal (SRS) in user equipment (UE) in a coordinated multi-point transmission/reception system (CoMP system), the method comprising:
 receiving, by the user equipment, UE-specific configuration information including a sounding reference signal (SRS) identity from a first transmission/reception point among a plurality of different transmission/reception points, wherein the SRS identity is independently determined to be distinguished from an uplink reference signal identity for an uplink channel and indicates a second transmission/reception point as a reception entity of an SRS; and   performing, by the user equipment, an independent transmission of the uplink channel and the SRS to different transmission/reception points, using the uplink reference signal identity or the SRS identity according to a type of an uplink transmission,
 wherein when the type of the uplink transmission is an SRS transmission, the performing includes: 
 generating, by the user equipment, an SRS using the SRS identity included in the received UE-specific configuration information; 
 determining the second transmission/reception point UE-specifically indicated by the SRS identity, as an SRS reception entity, wherein the second transmission/reception point is different from the first transmission/reception point which has transmitted the UE-specific configuration information to the user equipment; and 
 transmitting, by the user equipment, the generated SRS to the determined second transmission/reception point; 
   wherein the SRS includes a periodic SRS and an aperiodic SRS;   wherein the generating an SRS includes generating both the periodic SRS and the aperiodic SRS using the SRS identity; and   wherein the receiving UE-specific configuration information includes receiving, from the first transmission/reception point, the UE-specific configuration information including the SRS identity, either through a UE-specific parameter, or dynamically through at least one of a physical downlink control channel (PDCCH) and an enhanced physical downlink control channel (EPDCCH).   
     
     
       16. The method of claim 15, wherein:
 the UE-specific configuration information includes the sounding reference signal identity which is the same for the periodic SRS and the aperiodic SRS.    
     
     
       17. The method of claim 15, wherein:
 the UE-specific configuration information includes the sounding reference signal identity which is different for the periodic SRS and the aperiodic SRS.