Method and system for setting reference signal in wireless communication system
A method and a system of setting up a reference signal in a radio communication system. The radio communication system includes a serving cell and a neighboring cell, and a mobile terminal of the serving cell uses the same temporal frequency resource so as to receive a serving resource block from the serving cell and receive an interference resource block from the neighboring cell. The method according to the present disclosure includes a step of setting up a user-specific reference signal in the interference resource block and a step in which puncturing is performed at same temporal frequency position as the temporal frequency position at which the user-specific reference signal is set up on the interference resource block of the serving resource block so as to prevent any signal from being transmitted at the punctured temporal frequency position. When the method and the system provided in the present disclosure are used and the interference power between cells is thereby measured, it is possible to effectively reduce feedback overhead in a coordinated beamforming.
1. A method for mapping a reference signal, the method comprising:
mapping a reference signal to at least one first resource of a plurality of resources in a resource block, the plurality of resources in the resource block having different time-frequencies; and
selecting at least one second resource, on which no signal is transmitted in a cell, from the plurality of resources,
wherein, to a terminal in the cell, the mapped reference signal is transmitted on the at least one first resource while no signal is transmitted on the selected at least one second resource.
2. The method according to claim 1 , wherein a resource having a time-frequency that is same as a time-frequency of a resource, to which a reference signal is mapped in another cell, is selected as the at least one second resource.
3. The method according to claim 1 , wherein the cell performs a coordinated transmission with another cell.
4. The method according to claim 1 , wherein the cell performs a coordinated beamforming with another cell.
5. The method according to claim 1 , wherein the reference signal is used for measuring channel information at the terminal.
6. The method according to claim 5 , wherein the channel information is channel state information (CSI) or precoding matrix index (PMI).
7. The method according to claim 1 , further comprising obtaining channel information, which is measured at the terminal based on the reference signal.
8. The method according to claim 1 , further comprising obtaining channel information that the terminal measures in the at least one second resource, on which no signal is transmitted to the terminal in the cell, the channel information being measured based on a reference signal transmitted in another cell.
9. The method according to claim 1 , wherein the plurality of resources are comprised of resources used for transmission of control information and resources used for transmission of data signal, the reference signal is mapped to at least one resource of the resources used for transmission of the data signal, and the at least one second resource, on which no signal is transmitted to the terminal in the cell, is selected from the resources used for transmission of the data signal.
10. The method according to claim 1 , wherein a Rel-8 reference signal is mapped to at least one resource of the plurality of resources, and the reference signal is mapped to a resource different from a resource, to which the Rel-8 reference signal is mapped.
11. The method according to claim 1 , wherein the plurality of resources include a resource used for transmission of a demodulation reference signal, and the reference signal is mapped to a resource used for transmission of the demodulation reference signal.
12. The method according to claim 1 , wherein the plurality of resources include a resource used for transmission of a demodulation reference signal, and the reference signal is mapped to a resource different from a resource used for transmission of the demodulation reference signal.
13. The method according to claim 1 , wherein the reference signal is mapped in a plurality of resource blocks having a given interval.
14. The method according to claim 1 , wherein the reference signal is a power sensing reference signal.
15. A base station apparatus configured to perform the method for mapping a reference signal according to claim 1 .
16. A method for measuring channel information, the method comprising:
receiving a first reference signal that is mapped to at least one resource of a plurality of resources in a resource block and that is transmitted in a cell, and a second reference signal that is mapped to at least another resource of the plurality of resources in the resource block and that is transmitted in another cell, wherein no signal is transmitted in the cell on said at least another resource to which the second reference signal transmitted in the other cell is mapped, the plurality of resources in the resource block having different time-frequencies; and
measuring channel information based on at least one of the first and second reference signals.
17. The method according to claim 16 , wherein the cell is a serving cell.
18. The method according to claim 16 , wherein the cell performs a coordinated transmission with the other cell.
19. The method according to claim 16 , wherein the cell performs a coordinated beamforming with the other cell.
20. The method according to claim 16 , wherein the channel information is channel state information (CSI) or precoding matrix index (PMI).
21. The method according to claim 16 , wherein the plurality of resources are comprised of resources used for transmission of control information and resources used for transmission of data signal, the first reference signal is mapped to at least one resource of the resources used for transmission of the data signal, and the second reference signal is mapped to at least one resource of the resources used for transmission of the data signal.
22. The method according to claim 16 , further comprising receiving a Rel-8 reference signal mapped to at least one resource of the plurality of resources, wherein the first reference signal is mapped to a resource different from a resource, to which the Rel-8 reference signal is mapped.
23. The method according to claim 16 , wherein the plurality of resources include a resource used for transmission of a demodulation reference signal, and the first reference signal is mapped to a resource used for transmission of the demodulation reference signal.
24. The method according to claim 16 , wherein the plurality of resources include a resource used for transmission of a demodulation reference signal, and the first reference signal is mapped to a resource different from a resource used for transmission of the demodulation reference signal.
25. The method according to claim 16 , wherein the first reference signal is mapped in a plurality of resource blocks having a given interval.
26. The method according to claim 16 , wherein the first reference signal is a power sensing reference signal.
27. A terminal apparatus configured to perform the method for measuring channel information according to claim 16 .
28. A base station apparatus comprising:
a mapping section configured to map a reference signal to at least one first resource of a plurality of resources in a resource block, the plurality of resources in the resource block having different time-frequencies; and
a selecting section configured to select at least one second resource, on which no signal is transmitted in a cell, from the plurality of resources,
wherein, to a terminal in the cell, the mapped reference signal is transmitted on the at least one first resource while no signal is transmitted on the selected at least one second resource.
29. The base station apparatus according to claim 28 , wherein said selecting section selects a resource having a time-frequency that is same as a time-frequency of a resource, to which a reference signal is mapped in another cell, as the at least one second resource.
30. The base station apparatus according to claim 28 , further comprising an obtaining section configured to obtain channel information, which is measured at the terminal based on the reference signal.
31. The base station apparatus according to claim 30 , wherein said obtaining section obtains channel information that the terminal measures in the at least one second resource, on which no signal is transmitted to the terminal in the cell, the channel information being measured based on a reference signal transmitted in another cell.
32. The base station apparatus according to claim 28 , wherein said mapping section maps a Rel-8 reference signal to at least one resource of the plurality of resources, and maps the reference signal to a resource different from a resource, to which the Rel-8 reference signal is mapped.
33. A terminal apparatus comprising:
a receiving section configured to receive a first reference signal that is mapped to at least one resource of a plurality of resources in a resource block and that is transmitted in a cell, and a second reference signal that is mapped to at least another resource of the plurality of resources in the resource block and that is transmitted in another cell, wherein no signal is transmitted in the cell on said at least another resource to which the second reference signal transmitted in the other cell is mapped, the plurality of resources in the resource block having different time-frequencies; and
a measurement section configured to measure channel information based on at least one of the first and second reference signals.
34. The terminal apparatus according to claim 33 , wherein said receiving section receives a Rel-8 reference signal mapped to at least one resource of the plurality of resources, and receives the first reference signal mapped to a resource different from a resource, to which the Rel-8 reference signal is mapped.