Reduced CSI (channel state information)-RS (reference signal) density support for FD (full dimensional)-MIMO (multiple input multiple output) systems
Techniques discussed herein can facilitate reduced density CSI (Channel State Information)-RS (Reference Signals). One example embodiment can be employed at a UE (User Equipment) and can comprise processing circuitry configured to: process one or more configuration messages that comprise one or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS, wherein the one or more configuration parameters indicate a PRB (Physical Resource Block) decimation and a PRB offset; determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the one or more configuration parameters; measure the reduced density CSI-RS from the set of REs to determine one or more CSI parameters.
1. An apparatus configured to be employed in a UE (User Equipment), comprising:
a memory interface; and
processing circuitry configured to:
process one or more configuration messages that comprise two or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS;
determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the two or more configuration parameters; and
perform measurements on the reduced density CSI-RS from the set of REs to determine one or more CSI parameters;
wherein the two or more configuration parameters comprise indications of a PRB (Physical Resource Block) decimation and a PRB offset indicated separately in the one or more configuration messages; and
wherein the two or more configuration parameters are provided per CSI-RS resource configuration.
2. The apparatus of claim 1 , wherein the one or more CSI-RS APs comprise a single CSI-RS AP.
3. The apparatus of claim 1 , wherein the one or more CSI-RS APs comprise two or more CSI-RS APs in a CSI-RS group.
4. The apparatus of claim 3 , wherein the two or more CSI-RS APs in the CSI-RS group comprise a first half of configured CSI-RS APs for the UE or a second half of configured CSI-RS APs for the UE.
5. The apparatus of claim 1 , wherein the one or more CSI-RS APs comprise each CSI-RS AP of a CSI-RS resource configuration.
6. An apparatus configured to be employed in a base station, comprising:
a memory interface; and
processing circuitry configured to:
generate one or more configuration messages that comprise two or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS, wherein the two or more configuration parameters comprise indications of a PRB (Physical Resource Block) decimation and a PRB offset;
determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the two or more configuration parameters; and
map the reduced density CSI-RS for the one or more CSI-RS APs to the determined set of REs;
wherein the two or more configuration parameters are provided per CSI-RS resource configuration.
7. The apparatus of claim 6 , wherein the one or more configuration messages comprise a RRC (Radio Resource Control) message that comprises the PRB decimation and a DCI (Downlink Control Information) message that comprises the PRB offset.
8. The apparatus of claim 6 , wherein the one or more configuration messages comprises a RRC (Radio Resource Control) message.
9. The apparatus of claim 6 , wherein the one or more configuration messages comprises a DCI (Downlink Control Information) message.
10. The apparatus of claim 6 , wherein the one or more CSI-RS APs comprise a single CSI-RS AP.
11. The apparatus of claim 6 , wherein the one or more CSI-RS APs comprise two or more CSI-RS APs in a CSI-RS group.
12. The apparatus of claim 11 , wherein the two or more CSI-RS APs in the CSI-RS group comprise a first half of configured CSI-RS APs or a second half of configured CSI-RS APs.
13. The apparatus of claim 6 , wherein the one or more CSI-RS APs comprise each CSI-RS AP of a CSI-RS resource configuration.
14. The apparatus of claim 6 , wherein the processing circuitry is further configured to perform collision handling between the reduced density CSI-RS and at least one of paging messages or broadcast messages based on an assumption of a non-reduced density CSI-RS corresponding to the reduced density CSI-RS.
15. The apparatus of claim 6 , wherein the processing circuitry is further configured to renumber the one or more CSI-RS APs such that the processing circuitry is configured to map the reduced density CSI-RS for one CSI-RS AP to a first RE of an associated RE pair of an associated CDM (Code Division Multiplexing) group and to map, to a second RE of the associated RE pair of the associated CDM group, the reduced density CSI-RS for an additional CSI-RS AP, wherein that CSI-RS AP and the additional CSI-RS AP are associated with a common beam, wherein that CSI-RS is associated with a first polarization of the common beam and the additional CSI-RS AP is associated with a distinct second polarization of the common beam.
16. A non-transitory machine readable medium comprising instructions that, when executed, cause a User Equipment (UE) to:
receive one or more configuration messages that comprise two or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS;
determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the two or more configuration parameters;
receive the reduced density CSI-RS from the set of REs; and
measure the reduced density CSI-RS to determine one or more CSI parameters;
wherein the one or more configuration messages comprise indications of a PRB (Physical Resource Block) decimation and a PRB offset indicated separately in the one or more configuration messages; and
wherein the two or more configuration parameters are provided per CSI-RS resource configuration.
17. A non-transitory machine readable medium comprising instructions that, when executed, cause a base station to: transmit one or more configuration messages that comprise two or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS, wherein the two or more configuration parameters comprise indications of a PRB (Physical Resource Block) decimation and a PRB offset; determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the two or more configuration parameters; and transmit the reduced density CSI-RS for the one or more CSI-RS APs via the determined set of REs; and wherein the two or more configuration parameters are provided per CSI-RS resource configuration.
18. The non-transitory machine readable medium of claim 17 , wherein the two or more configuration parameters comprise the PRB decimation and the PRB offset.
19. The apparatus of claim 1 , wherein PRB decimation indicates a number of PRBs per AP, and wherein the PRB offset indicates an offset number of PRBs from a reference PRB.
20. The apparatus of claim 6 , wherein PRB decimation indicates a number of PRBs per AP, and wherein the PRB offset indicates an offset number of PRBs from a reference PRB.
21. The non-transitory machine readable medium of claim 16 , wherein PRB decimation indicates a number of PRBs per AP, and wherein the PRB offset indicates an offset number of PRBs from a reference PRB.
22. The non-transitory machine readable medium of claim 17 , wherein PRB decimation indicates a number of PRBs per AP, and wherein the PRB offset indicates an offset number of PRBs from a reference PRB.