Method and apparatus for channel state information reference signal (CSI-RS)

1. A user equipment (UE), comprising:

a transceiver configured to:

receive higher-layer configuration information for N channel state information (CSI) reporting settings and M resource settings, and

receive downlink control information (DCI) that includes a DCI field for requesting aperiodic CSI reporting; and

a processor operably connected to the transceiver, the processor configured to:

decode the higher-layer configuration information and the DCI, and

calculate a CSI according to the higher-layer configuration information and the DCI,

wherein the transceiver is further configured to transmit the calculated CSI on an uplink (UL) channel,

wherein N is at least one, M is at least one, and the DCI field indicates a selection of one out of X STATE configured states, and

wherein:

the X STATE configured states are a subset of N STATE higher-layer configured states,

the subset is configured via a media access control (MAC) control element if N STATE is greater than X STATE , and

the X STATE configured states are higher-layer configured if N STATE is not greater than X STATE .

2. The UE of claim 1 , wherein the state is associated with at least one of report settings and resource setting pair.

3. The UE of claim 1 , wherein:

at least one of the M Resource settings includes at least one CSI-reference signal (RS) resource set, and

the at least one CSI-RS resource set includes at least one CSI-RS resource.

4. The UE of claim 3 , wherein at least one of the X STATE configured states corresponds to the at least one CSI-RS resource set.

5. The UE of claim 1 , wherein at least one of the X STATE configured states corresponds to at least one downlink component carrier.

6. The UE of claim 1 , wherein at least one of X STATE and N STATE is higher-layer configured.

7. The UE of claim 1 , wherein at least one of the X STATE configured states corresponds to at least one CSI reporting setting.

8. A base station (BS), comprising:

a processor configured to generate (i) higher-layer configuration information for N channel state information (CSI) reporting settings and M Resource settings and (ii) downlink control information (DCI) that includes a DCI field for requesting aperiodic CSI reporting; and

a transceiver operably connected to the processor, the transceiver configured to:

transmit the higher-layer configuration information and the DCI to a user equipment (UE) via one or more downlink (DL) control channels, and

receive, from the UE, a CSI report calculated in accordance with the higher-layer configuration information and the DCI on an uplink (UL) channel,

wherein N is at least one, M is at least one, and the DCI field includes a selection of one out of X STATE configured states, and

wherein:

the X STATE configured states are a subset of N STATE higher-layer configured states,

the subset is configured via a media access control (MAC) control element if N STATE is greater than X STATE , and

the X STATE configured states are higher-layer configured if N STATE is not greater than X STATE .

9. The BS of claim 8 , where in the state is associated with at least one of report settings and resource setting pair.

10. The BS of claim 8 , wherein:

at least one of the M Resource settings includes at least one CSI-reference signal (RS) resource set, and

the at least one CSI-RS resource set includes at least one CSI-RS resource.

11. The BS of claim 10 , wherein at least one of the X STATE configured states corresponds to the at least one CSI-RS resource set.

12. The BS of claim 8 , wherein at least one of the X STATE configured states corresponds to at least one DL component carrier.

13. The BS of claim 8 , wherein at least one of the X STATE configured states corresponds to at least one CSI reporting setting.

14. A method for operating a user equipment (UE), the method comprising:

receiving and decoding higher-layer configuration information for N channel state information (CSI) reporting settings and M Resource settings;

receiving downlink control information (DCI) that includes a DCI field for requesting aperiodic CSI reporting;

calculating a CSI according to the higher-layer configuration information and the DCI; and

transmitting the calculated CSI on an uplink (UL) channel,

wherein N is at least one, M is at least one, and the DCI field includes a selection of one out of X STATE configured states, and

wherein:

the X STATE configured states are a subset of N STATE higher-layer configured states,

the subset is configured via a media access control (MAC) control element if N STATE is greater than X STATE , and

the X STATE configured states are higher-layer configured if N STATE is not greater than X STATE .

15. The method of claim 14 , wherein the state is associated with at least one of report settings and resource setting pair.

16. The method of claim 14 , wherein:

at least one of the M Resource settings includes at least one CSI-reference signal (RS) resource set, and

the at least one CSI-RS resource set includes at least one CSI-RS resource.

17. The method of claim 16 , wherein at least one of the X STATE configured states corresponds to the at least one CSI-RS resource set.

18. The method of claim 14 , wherein at least one of the X STATE configured states corresponds to at least one downlink component carrier.

19. The method of claim 18 , wherein at least one of X STATE and N STATE is higher-layer configured.

20. The method of claim 14 , wherein at least one of the X STATE configured states corresponds to at least one CSI reporting setting.