Method for transmitting dedicated reference signal, and method for receiving dedicated reference signal

Abstract

Provided are a method of transmitting a dedicated reference signal (DRS), a method of receiving a DRS, and a feedback method of a terminal. The method of transmitting a DRS includes determining a DRS transmitting resource for at least one terminal which is a target of transmission, and transmitting the DRS using the determined transmission resource and notifying the terminal of information about layer used by the terminal. The method of receiving a DRS includes determining a DRS receiving resource, receiving information about layer used by a terminal from a serving cell base station, and receiving the DRS for the terminal using the determined reception resource and the information about layer. Accordingly, a terminal can find the position and sequence of its DRS. In particular, in the case of multi-user multiple input multiple output (MU-MIMO) or joint scheduling, it is possible to prevent or remove signal interference using the DRS of another terminal.

What is claimed is: 
     
       1. A method for a base station to transmit a reference signal to a terminal, the method comprising:
 transmitting, from the base station, a virtual terminal-specific information to the terminal;   generating a sequence for the reference signal for the terminal by using a physical cell identity (PCI) of a serving cell of the terminal and the virtual terminal-specific information; and   transmitting, from the base station, the reference signal using the sequence to the terminal,   wherein the virtual terminal-specific information is transmitted to the terminal by using downlink control information (DCI),   wherein the reference signal is a dedicated reference signal for the terminal.   
     
     
       2. The method of  claim 1 , further comprising transmitting information about layer used by the terminal to the terminal. 
     
     
       3. The method of  claim 1 , wherein the virtual terminal-specific information is shared by at least two terminals including the terminal and selected among plural values predefined for the at least two terminals. 
     
     
       4. The method of  claim 1 , wherein the virtual terminal-specific information is used for generating the sequence instead of a radio network temporary identifier (RNTI) of the terminal. 
     
     
       5. The method of  claim 1 , wherein the base station performs a single point transmission for the terminal. 
     
     
       6. A method for a terminal to receive a reference signal from a base station, the method comprising:
 receiving, from the base station, a virtual terminal-specific information from the base station;   generating a sequence for the reference signal for the terminal by using a physical cell identity (PCI) of a serving cell of the terminal and the virtual terminal-specific information; and   receiving, from the base station, the reference signal by using the sequence from the base station,   wherein the virtual terminal-specific information is received from the base station by using downlink control information (DCI),   wherein the reference signal is a dedicated reference signal for the terminal.   
     
     
       7. The method of  claim 6 , further comprising receiving information about layer used by the terminal from the base station. 
     
     
       8. The method of  claim 6 , wherein the virtual terminal-specific information is shared by at least two terminals including the terminal and selected among plural values predefined for the at least two terminals. 
     
     
       9. The method of  claim 6 , wherein the virtual terminal-specific information is used for generating the sequence instead of a radio network temporary identifier (RNTI) of the terminal. 
     
     
       10. The method of  claim 6 , wherein the terminal performs a single point reception from the base station. 
     
     
       11. A method for a base station to transmit a reference signal to a terminal, the method comprising:
 transmitting, from the base station, a virtual cell-specific information and a virtual terminal-specific information to the terminal;   generating a sequence for the reference signal for the terminal by using the virtual cell-specific information and the virtual terminal-specific information; and   transmitting, from the base station, the reference signal using the sequence to the terminal,   wherein the virtual cell-specific information is transmitted to the terminal by using downlink control information (DCI),   wherein the reference signal is a dedicated reference signal for the terminal.   
     
     
       12. The method of  claim 11 , wherein the virtual cell-specific information is indicated by the down link control information among a plurality of cell identities. 
     
     
       13. The method of  claim 11 , wherein the virtual terminal-specific information is transmitted to the terminal by using a downlink control information (DCI). 
     
     
       14. The method of  claim 11 , further comprising transmitting information about layer used by the terminal to the terminal. 
     
     
       15. The method of  claim 11 , wherein the virtual cell-specific information is shared by at least two cells including a serving cell of the terminal. 
     
     
       16. The method of  claim 11 , wherein the virtual terminal-specific information is shared by at least two terminals including the terminal and selected among plural values predefined for the at least two terminals. 
     
     
       17. The method of  claim 11 , wherein
 the virtual cell-specific information is identical to or different from a physical cell identity (PCI) of a serving cell of the terminal and   the virtual terminal-specific information is different from a radio network temporary identifier (RNTI) of the terminal.   
     
     
       18. The method of  claim 11 , wherein the base station performs a coordinated multi-point transmission for the terminal with other base station. 
     
     
       19. A method for a terminal to receive a reference signal from a base station, the method comprising:
 receiving, from the base station, a virtual cell-specific information and a virtual terminal-specific information from the base station;   generating a sequence for the reference signal for the terminal by using the virtual cell-specific information and the virtual terminal-specific information; and   receiving, from the base station, the reference signal by using the sequence from the base station,   wherein the virtual cell-specific information is received from the base station by using downlink control information (DCI),   wherein the reference signal is a dedicated reference signal for the terminal.   
     
     
       20. The method of  claim 19 , wherein the virtual cell-specific information is indicated by the down link control information among a plurality of cell identities. 
     
     
       21. The method of  claim 19 , wherein the virtual terminal-specific information is received from the terminal by using a downlink control information (DCI). 
     
     
       22. The method of  claim 19 , further comprising receiving information about layer used by the terminal from the base station. 
     
     
       23. The method of  claim 19 , wherein the virtual cell-specific information is shared by at least two cells including a serving cell of the terminal. 
     
     
       24. The method of  claim 19 , wherein the virtual terminal-specific information is shared by at least two terminals including the terminal and selected among plural values predefined for the at least two terminals. 
     
     
       25. The method of  claim 19 , wherein
 the virtual cell-specific information is identical to or different from a physical cell identity (PCI) of a serving cell of the terminal and   the virtual terminal-specific information is different from a radio network temporary identifier (RNTI) of the terminal.   
     
     
       26. The method of  claim 19 , wherein the terminal performs a coordinated multi-point reception from a plurality of cells including a serving cell of the terminal. 
     
     
       27. A terminal to receive a reference signal from a base station, the terminal comprising:
 a memory, and   a processor operably coupled to one or more antennas to receive the reference signal,   wherein the processor, when executing program instructions stored in the memory, is configured to:   cause the terminal to receive, from the base station, downlink control information (DCI), wherein the DCI includes first terminal-specific information;   cause the terminal to receive, from the base station, the reference signal; and   cause the terminal to obtain user data based on the reference signal, the first terminal-specific information and a physical layer cell identity (PCI) of a serving cell,   wherein the reference signal is a dedicated reference signal for the terminal.   
     
     
       28. The terminal of claim 27, wherein the reference signal is a user equipment specific (UE-specific) reference signal. 
     
     
       29. The terminal of claim 27, wherein the DCI is also transmitted to a second terminal and the reference signal is also transmitted to the second terminal. 
     
     
       30. The terminal of claim 27, wherein the processor is further configured to:
 cause the terminal to receive a virtual cell identity of the serving cell from the base station;   cause the terminal to receive another reference signal from the base station; and   cause the terminal to obtain other user data based on the another reference signal, the first terminal-specific information and the virtual cell identity of the serving cell.   
     
     
       31. The terminal of claim 27, wherein the terminal performs a single point reception from the base station. 
     
     
       32. A communication device for a terminal, the communication device comprising:
 a memory, and   a processor,   wherein the processor, when executing program instructions stored in the memory, is configured to:
 cause the terminal to receive, from a base station, downlink control information (DCI), wherein the DCI includes first terminal-specific information; 
 cause the terminal to receive, from the base station, the reference signal; and 
 cause the terminal to obtain user data based on the reference signal, the first terminal-specific information and a physical layer cell identity (PCI) of a serving cell, 
   wherein the reference signal is a dedicated reference signal for the terminal.   
     
     
       33. The communication device of claim 32, wherein the reference signal is a user equipment specific (UE-specific) reference signal. 
     
     
       34. The communication device of claim 32, wherein the DCI is also transmitted to a second terminal and the reference signal is also transmitted to the second terminal. 
     
     
       35. The communication device of claim 32, wherein the processor is further configured to:
 cause the terminal to receive a virtual cell identity of the serving cell from the base station;   cause the terminal to receive another reference signal from the base station; and   cause the terminal to obtain other user data based on the another reference signal, the first terminal-specific information and the virtual cell identity of the serving cell.   
     
     
       36. The communication device of claim 32, wherein the terminal performs a single point reception from the base station. 
     
     
       37. A communication method performed by a terminal, comprising:
 receiving, from the base station, downlink control information (DCI), wherein the DCI includes first terminal-specific information;   receiving, from the base station, a reference signal; and   obtaining user data based on the reference signal, the first terminal-specific information and a physical layer cell identity (PCI) of a serving cell,   wherein the reference signal is a dedicated reference signal for the terminal.   
     
     
       38. The method of claim 37, wherein the reference signal is a user equipment specific (UE-specific) reference signal. 
     
     
       39. The method of claim 37, wherein the DCI is also transmitted to a second terminal and the reference signal is also transmitted to the second terminal. 
     
     
       40. The method of claim 37, further comprising:
 receiving a virtual cell identity of the serving cell from the base station;   receiving another reference signal from the base station; and   obtaining other user data based on the another reference signal, the first terminal-specific information and the virtual cell identity of the serving cell.   
     
     
       41. The method of claim 37, wherein the terminal performs a single point reception from the base station.