Signaling for MU interference measurement with NZP CSI-RS
Systems and methods are disclosed herein for determining Non-Zero Power (NZP) Channel State Information Reference Signal (CSI-RS) resources to be used for channel and interference measurement. In some embodiments, a method performed by a wireless device comprises receiving, from a network node, a semi-static indication of one or more first sets of NZP CSI-RS resources for channel measurement and a semi-static indication of one or more second sets of NZP CSI-RS resources for interference measurement. The method further comprises receiving, from the network node, one or more dynamic indications that indicate a first set of NZP CSI-RS resources from the one or more first sets of NZP CSI-RS resources to be used by the wireless device for channel measurement and a second set of NZP CSI-RS resources from the one or more second sets of NZP CSI-RS resources to be used by the wireless device for interference measurement.
1. A method for a user equipment, the method comprising:
receiving, from a base station of a wireless communication system, a semi-static indication of a Channel State Information, CSI, reporting setting comprising one or more sets of aperiodic Non-Zero Power, NZP, Channel State Information Reference Signal, CSI-RS, resources for channel measurement wherein each of the one or more sets of aperiodic NZP CSI-RS resources contains a single aperiodic NZP CSI-RS resource with precoded CSI-RS port(s), and one or more sets of aperiodic NZP CSI-RS resources for interference measurement, wherein each of the one or more sets of aperiodic NZP CSI-RS resources contain one or more NZP CSI-RS resources and each CSI-RS port in the one or more sets of aperiodic NZP CSI-RS resources corresponds to a Multiple User Multiple Input Multiple Output, MU-MIMO, interference layer associated with a co-scheduled user equipment;
receiving, from the base station, a dynamic indication requesting a CSI report according to the CSI reporting setting and a first set of aperiodic NZP CSI-RS resources from the one or more sets of aperiodic NZP CSI-RS resources for channel measurement and a second set of aperiodic NZP CSI-RS resources from the one or more sets of aperiodic NZP CSI-RS resources for interference measurement; and
reporting a CSI comprising a rank and a Channel Quality Indicator, CQI.
2. The method of claim 1 further comprising:
performing channel measurement on the first set of aperiodic NZP CSI-RS resources; and
performing interference measurement on the second set of aperiodic NZP CSI-RS resources.
3. The method of claim 1 wherein each aperiodic NZP CSI-RS resource consists of one or multiple CSI-RS ports.
4. The method of claim 1 wherein each aperiodic NZP CSI-RS resource consists of one, two, or four ports.
5. The method of claim 1 wherein each aperiodic NZP CSI-RS resource set in the one or more sets of aperiodic NZP CSI-RS resources for interference measurement consists of a number, K, of aperiodic NZP CSI-RS resources, wherein K is greater than or equal to 1.
6. The method of claim 1 wherein the one or more sets of aperiodic NZP CSI-RS resources for channel measurement are associated with a first resource setting and the one or more sets of aperiodic NZP CSI-RS resources for interference measurement are associated with a second resource setting, the first resource setting being different than the second resources setting.
7. The method of claim 1 wherein the dynamic indication is contained in Downlink Control Information, DCI.
8. The method of claim 1 wherein the first set of aperiodic NZP CSI-RS resource and the second set of aperiodic NZP CSI-RS resources are jointly indicated by a same Downlink Control Information, DCI, field.
9. A user equipment comprising an interface and processing circuitry whereby the user equipment is operable to:
receive, from a base station of the wireless communication system, a semi-static indication of a Channel State Information, CSI, reporting setting comprising one or more sets of aperiodic Non-Zero Power, NZP, Channel State Information Reference Signal, CSI-RS, resources for channel measurement wherein each of the one or more sets of aperiodic NZP CSI-RS resources contains a single aperiodic NZP CSI-RS resource with precoded CSI-RS port(s), and one or more sets of aperiodic NZP CSI-RS resources for interference measurement, wherein each of the one or more sets of aperiodic NZP CSI-RS resources contain one or more NZP CSI-RS resources and each CSI-RS port in the one or more NZP CSI-RS resources corresponds to a Multiple User Multiple Input Multiple Output, MU-MIMO, interference layer associated with a co-scheduled user equipment;
receive, from the base station, a dynamic indication requesting a CSI report according to the CSI reporting setting and a first set of aperiodic NZP CSI-RS resources from the one or more sets of aperiodic NZP CSI-RS resources for channel measurement and a second set of aperiodic NZP CSI-RS resources from the one or more sets of aperiodic NZP CSI-RS resources for interference measurement; and
report a CSI comprising a rank and a Channel Quality Indicator, CQI.
10. The user equipment of claim 9 wherein, via the interface and the processing circuitry, the user equipment is further operable to:
perform channel measurement on the first set of aperiodic NZP CSI-RS resources; and
perform interference measurement on the second set of aperiodic NZP CSI-RS resources.
11. The user equipment of claim 9 wherein, via the interface and the processing circuitry, the user equipment is further operable to report results of the channel measurement and the interference measurement to the base station.
12. A method performed by a base station for configuring a user equipment, the method comprising:
sending, to the user equipment, a semi-static indication of a Channel State Information,
CSI, reporting setting comprising one or more sets of aperiodic Non-Zero Power, NZP, Channel State Information Reference Signal, CSI-RS, resources for channel measurement, wherein each of the one or more sets of aperiodic NZP CSI-RS resources contains a single aperiodic NZP CSI-RS resource with precoded CSI-RS port(s), and one or more sets of aperiodic NZP CSI-RS resources for interference measurement, wherein each of the one or more sets of aperiodic NZP CSI-RS resources contain one or more NZP CSI-RS resources and each CSI-RS port in the one or more NZP CSI-RS resources corresponds to a Multiple User Multiple Input Multiple Output, MU-MIMO, interference layer associated with a co-scheduled user equipment;
sending, to the user equipment, a dynamic indication requesting a CSI report according to the CSI reporting setting and a first set of aperiodic NZP CSI-RS resources from the one or more sets of aperiodic NZP CSI-RS resources for channel measurement and a second set of aperiodic NZP CSI-RS resources from the one or more sets of aperiodic NZP CSI-RS resources for interference measurement; and
receiving, from the user equipment, a CSI report comprising a rank and a Channel Quality Indicator, CQI.
13. A base station for configuring a user equipment comprising an interface and processing circuitry whereby the base station is operable to:
send, to the user equipment, a semi-static indication of a Channel State Information, CSI, reporting setting comprising one or more sets of aperiodic Non-Zero Power, NZP, Channel State Information Reference Signal, CSI-RS, resources for channel measurement, wherein each of the one or more sets of aperiodic NZP CSI-RS resources contains a single aperiodic NZP CSI-RS resource with precoded CSI-RS port(s), and one or more sets of aperiodic NZP CSI-RS resources for interference measurement, wherein each of the one or more sets of aperiodic NZP CSI-RS resources contain one or more NZP CSI-RS resources and each CSI-RS port in the one or more NZP CSI-RS resources corresponds to a Multiple User Multiple Input Multiple Output, MU-MIMO, interference layer associated with a co-scheduled user equipment;
send, to the user equipment, a dynamic indication requesting a CSI report according to the CSI reporting setting and a first set of aperiodic NZP CSI-RS resources from the one or more sets of aperiodic NZP CSI-RS resources for channel measurement and a second set of aperiodic NZP CSI-RS resources from the one or more sets of aperiodic NZP CSI-RS resources for interference measurement; and
receive, from the user equipment, a CSI report comprising a rank and a Channel Quality Indicator, CQI.