Method for reporting channel state information, user equipment, and base station
The present disclosure relates to a method for reporting channel state information, a user equipment, and a base station. A channel state information measurement resource is determined by a UE according to an aperiodic CSI trigger signaling, so that a base station transmits a CSI-RS only when the UE needs to report the aperiodic CSI. Compared with transmitting a periodic CSI-RS by an existing base station, unnecessary transmitting of the CSI-RS is reduced, and energy of the base station such as an eNB is saved; and reducing the CSI-RS transmission may reduce resources occupied by the CSI-RS, thereby improving the spectrum efficiency of the system. In addition, reducing unnecessary CSI-RS transmission allows the interference in other cells by the base station being reduced; finally, CSI measurement resources are reserved only when the CSI needs to be fed back, the cost occupied by the CSI measurement resources is reduced.
1. A method carried out by a terminal, the method comprising:
receiving in a time unit n, from a network device, a downlink control information (DCI) comprising an information for triggering an aperiodic channel state information (CSI) report, wherein the information for triggering the aperiodic CSI report indicates a resource for an aperiodic channel state information reference signal (CSI-RS);
determining the resource for the aperiodic CSI-RS according to the information for triggering the aperiodic CSI report, wherein the resource for the aperiodic CSI-RS is in a time unit n+k5, and k5 is an integer greater than or equal to 0;
sending, to the network device, the aperiodic CSI report, wherein the aperiodic CSI report is derived by the terminal according to the aperiodic CSI-RS on the resource for the aperiodic CSI-RS.
2. The method according to claim 1 , wherein the resource for the aperiodic CSI-RS is a resource for an aperiodic non-zero power CSI-RS.
3. The method according to claim 1 , further comprising:
receiving, from the network device, a measurement resource configuration indication information, wherein the measurement resource configuration indication information indicates at least one of a number of CSI-RS antenna ports, a CSI-RS configuration or a zero power CSI-RS configuration.
4. The method according to claim 3 , wherein the measurement resource configuration indication information is semi-statically configured for the terminal.
5. The method according to claim 4 , wherein the measurement resource configuration indication information excludes sub-frame configuration information.
6. A method carried out by a network device, the method comprising:
transmitting in a time unit n, to a terminal, a downlink control information (DCI) comprising an information for triggering an aperiodic channel state information (CSI) report, wherein the information for triggering the aperiodic CSI report indicates a resource for an aperiodic channel state information reference signal (CSI-RS), and wherein the resource for the aperiodic CSI-RS is in a time unit n+k5, and k5 is an integer greater than or equal to 0;
transmitting in the time unit n+k5, to the terminal, the aperiodic CSI-RS on the resource for the aperiodic CSI-RS; and
receiving, from the terminal, the aperiodic CSI report.
7. The method according to claim 6 , wherein the aperiodic CSI-RS comprises an aperiodic non-zero power CSI-RS.
8. The method according to claim 6 , further comprising:
transmitting, to the terminal, a measurement resource configuration indication information, wherein the measurement resource configuration indication information indicates at least one of a number of CSI-RS antenna ports, a CSI-RS configuration or a zero power CSI-RS configuration.
9. The method according to claim 8 , wherein the measurement resource configuration indication information is semi-statically configured for the terminal.
10. The method according to claim 9 , wherein the measurement resource configuration indication information excludes sub-frame configuration information.
11. The method according to claim 1 , wherein the time unit n is a subframe n, and the time unit n+k5 is a subframe n+k5.
12. The method according to claim 6 , wherein the time unit n is a subframe n, and the time unit n+k5 is a subframe n+k5.
13. The method according to claim 1 , further comprising:
deriving, by the terminal, the aperiodic CSI report according to the aperiodic CSI-RS on the resource for the aperiodic CSI-RS.
14. The method according to claim 1 , wherein the aperiodic CSI-RS is only transmitted when the DCI comprising the information for triggering the aperiodic CSI report has been transmitted.
15. The method according to claim 6 , wherein the aperiodic CSI-RS is only transmitted when the DCI comprising the information for triggering the aperiodic CSI report has been transmitted.
16. An apparatus, comprising:
a non-transitory processor readable medium storing instructions; and a processor executing the instructions stored in the non-transitory processor readable medium, wherein execution of the instructions configures the apparatus to:
receive in a time unit n, from a network device, a downlink control information (DCI) comprising an information for triggering an aperiodic channel state information (CSI) report, wherein the information for triggering the aperiodic CSI report indicates a resource for an aperiodic channel state information reference signal (CSI-RS);
determine the resource for the aperiodic CSI-RS according to the information for triggering the aperiodic CSI report, wherein the resource for the aperiodic CSI-RS is in a time unit n+k5, and k5 is an integer greater than or equal to 0; and
send, to the network device, the aperiodic CSI report, wherein the aperiodic CSI report is derived by the apparatus according to the aperiodic CSI-RS on the resource for the aperiodic CSI-RS.
17. The apparatus according to claim 16 , wherein the resource for the aperiodic CSI-RS is a resource for an aperiodic-non-zero power CSI-RS.
18. The apparatus according to claim 16 , wherein the execution of the instructions further configures the apparatus to:
receive, from the network device, a measurement resource configuration indication information, wherein the measurement resource configuration indication information indicates at least one of a number of CSI-RS antenna ports, a CSI-RS configuration or a zero power CSI-RS configuration.
19. The apparatus according to claim 18 , wherein the measurement resource configuration indication information is semi-statically configured.
20. The apparatus according to claim 19 , wherein the measurement resource configuration indication information excludes sub-frame configuration information.
21. The apparatus according to claim 16 , wherein the time unit n is a subframe n, and the time unit n+k5 is a subframe n+k5.
22. The apparatus according to claim 16 , wherein the execution of the instructions further configures the apparatus to derive the aperiodic CSI report according to the aperiodic CSI-RS on the resource for the aperiodic CSI-RS.
23. The apparatus according to claim 16 , wherein the aperiodic CSI-RS is only transmitted when the DCI comprising the information for triggering the aperiodic CSI report has been transmitted.
24. An apparatus, comprising: a non-transitory processor readable medium storing instructions; and a processor executing the instructions stored in the non-transitory processor readable medium, wherein execution of the instructions configures the apparatus to:
transmit in a time unit n, to a terminal, a downlink control information (DCI) comprising an information for triggering an aperiodic channel state information (CSI) report, wherein the information for triggering the aperiodic CSI report indicates a resource for an aperiodic channel state information reference signal (CSI-RS), and wherein the resource for the aperiodic CSI-RS is in a time unit n+k5, and k5 is an integer greater than or equal to 0;
transmit in the time unit n+k5, to the terminal, the aperiodic CSI RS on the resource for the aperiodic CSI-RS; and
receive, from the terminal, the aperiodic CSI report.
25. The apparatus according to claim 24 , wherein the aperiodic CSI-RS comprises an aperiodic non-zero power CSI-RS.
26. The apparatus according to claim 24 , wherein the execution of the instructions further configures the apparatus to:
transmit, to the terminal, a measurement resource configuration indication information, wherein the measurement resource configuration indication information is used to indicate at least one of a number of CSI-RS antenna ports, a CSI-RS configuration or a zero power CSI-RS configuration.
27. The apparatus according to claim 26 , wherein the measurement resource configuration indication information is semi-statically configured for the terminal.
28. The apparatus according to claim 27 , wherein the measurement resource configuration indication information excludes sub-frame configuration information.
29. The apparatus according to claim 24 , wherein the time unit n is a subframe n, and the time unit n+k5 is a subframe n+k5.
30. The apparatus according to claim 24 , wherein the aperiodic CSI-RS is only transmitted when the DCI comprising the information for triggering the aperiodic CSI report has been transmitted.
31. A non-transitory computer-readable storage medium comprising instructions that, when executed on a computer, cause the computer to:
receive in a time unit n, from a network device, a downlink control information (DCI) comprising an information for triggering an aperiodic channel state information (CSI) report, wherein the information for triggering the aperiodic CSI report indicates a resource for an aperiodic channel state information reference signal (CSI-RS);
determine the resource for the aperiodic CSI-RS according to the information for triggering the aperiodic CSI report, wherein the resource for the aperiodic CSI-RS is in a time unit n+k5, and k5 is an integer greater than or equal to 0;
send, to the network device, the aperiodic CSI report, wherein the aperiodic CSI report is derived according to the aperiodic CSI-RS on the resource for the aperiodic CSI-RS.
32. A non-transitory computer-readable storage medium comprising instructions that, when executed on a computer, cause the computer to:
transmit in a time unit n, to a terminal, a downlink control information (DCI) comprising an information for triggering an aperiodic channel state information (CSI) report, wherein the information for triggering the aperiodic CSI report indicates a resource for an aperiodic channel state information reference signal (CSI-RS), and wherein the resource for the aperiodic CSI-RS is in a time unit n+k5, and k5 is an integer greater than or equal to 0;
transmit in the time unit n+k5, to the terminal, the aperiodic CSI-RS on the resource for the aperiodic CSI-RS; and
receive, from the terminal, the aperiodic CSI report.