Rate matching of reference signal resources in multiple transmit receive point (TRP) scenarios
Certain aspects of the present disclosure provide techniques for rate matching PDSCH around NZP CSI RS transmissions in multi-TRP scenarios. In some cases, a network entity may signal a rate matching behavior to a user equipment (UE) for processing a physical downlink shared channel (PDSCH) configured with a first quasi co-location association and transmitted from a first transmission reception point (TRP) that potentially collides with one or more types of non-zero power (NZP) reference signals (RS) configured with a second quasi co-location association and transmitted from a second TRP using one or more resource sets.
1. A method of wireless communications by a user equipment (UE), comprising:
receiving radio resource control (RRC) signaling of at least one parameter indicating whether or how to perform rate matching for processing a physical downlink shared channel (PDSCH) associated with a first quasi co-location (QCL) association and transmitted from a first transmission reception point (TRP) that potentially collides with one or more non-zero power (NZP) reference signals (RS) associated with a second QCL association and transmitted from a second TRP, wherein each NZP RS is transmitted on one or more NZP resources within a NZP RS resource set, and wherein the signaling comprises a semi-static configuration of a list that indicates, for each of a plurality of cell identifiers (IDs) or QCL associations, whether or how to perform rate matching for NZP RS transmitted from that cell-ID or QCL association; and
processing the PDSCH transmission, wherein the processing comprises deciding whether or how to perform rate matching around the NZP RS based on the signaling.
2. The method of claim 1 , wherein the at least one parameter is signaled only for NZP RS resources configured aperiodically, for NZP RS resources used for interference measurement, for NZP RS resources used for channel measurement, or a combination thereof.
3. The method of claim 1 , wherein the UE is configured to process the PDSCH according to a default rate matching configuration if the at least one parameter is not signaled.
4. The method of claim 1 ,
further comprising receiving signaling of a configurable time window, per NZP RS resource set, to perform the rate matching.
5. The method of claim 4 , wherein the configurable time window is signaled for each of the cell-IDs or QCL associations.
6. The method of claim 5 , wherein a duration of the configurable time window is signaled via downlink control information (DCI) bits.
7. The method of claim 1 , wherein the NZP RS comprises at least one of:
NZP RS used for channel tracking purposes; or
NZP RS used for positioning purposes.
8. The method of claim 1 , wherein the at least one parameter is signaled for only certain multi-TRP configurations, and wherein each multi-TRP configuration specifies a number of physical downlink control channels (PDCCHs) associated with a number of PDSCHs.
9. The method of claim 1 , wherein:
the PDSCH transmission is sent using PDSCH slot aggregation; and
the method further comprises determining for which slots of the PDSCH transmission to perform the rate matching.
10. A method of wireless communications by a network entity, comprising:
determining whether or how for a user equipment (UE) to perform rate matching for processing a physical downlink shared channel (PDSCH) associated with a first quasi co-location (QCL) association and transmitted from a first transmission reception point (TRP) that potentially collides with one or more non-zero power (NZP) reference signals (RS) associated with a second QCL association and transmitted from a second TRP using one or more resource sets; and
sending radio resource control (RRC) signaling of at least one parameter indicating whether or how for the UE to perform rate matching, wherein the signaling comprises a semi-static configuration of a list that indicates, for each of a plurality of cell-identifiers (IDs) or QCL associations, whether or how to perform rate matching for NZP RS transmitted from that cell-ID or QCL association.
11. The method of claim 10 , wherein the at least one parameter is signaled only for NZP RS resources configured aperiodically, for NZP RS resources used for interference measurement, for NZP RS resources used for channel measurement, or a combination thereof.
12. The method of claim 10 , further comprising signaling a configurable time window, per resource set, for the UE to perform the rate matching.
13. The method of claim 10 , wherein the NZP RS comprises at least one of:
NZP RS used for channel tracking purposes; or
NZP RS used for positioning purposes.
14. The method of claim 10 , wherein the at least one parameter is signaled for only certain multi-TRP configurations, wherein each multi-TRP configuration specifies a number of physical downlink control channels (PDCCHs) associated with a number of PDSCHs.
15. The method of claim 10 , wherein:
the PDSCH transmission is sent using PDSCH slot aggregation; and
the method further comprises determining for which slots of the PDSCH transmission to perform the rate matching.
16. An apparatus for wireless communications by a user equipment (UE), comprising:
means for receiving radio resource control (RRC) signaling of at least one parameter indicating whether or how to perform rate matching for processing a physical downlink shared channel (PDSCH) associated with a first quasi co-location (QCL) association and transmitted from a first transmission reception point (TRP) that potentially collides with one or more types non-zero power (NZP) reference signals (RS) associated with a second QCL association and transmitted from a second TRP, wherein each NZP RS is transmitted on one or more NZP resources within a NZP RS resource set, and wherein the signaling comprises a semi-static configuration of a list that indicates, for each of a plurality of cell identifiers (IDs) or QCL associations, whether or how to perform rate matching for NZP RS transmitted from that cell-ID or QCL association; and
means for processing the PDSCH transmission, wherein the processing comprises deciding whether or how to perform rate matching around the NZP RS based on the signaling.
17. An apparatus for wireless communications by a network entity, comprising:
means for determining whether or how for a user equipment (UE) to perform rate matching for processing a physical downlink shared channel (PDSCH) associated with a first quasi co-location (QCL) association and transmitted from a first transmission reception point (TRP) that potentially collides with one or more non-zero power (NZP) reference signals (RS) associated with a second QCL association and transmitted from a second TRP using one or more resource sets; and
means for sending radio resource control (RRC) signaling of at least one parameter indicating whether or how for the UE to perform rate matching, wherein the signaling comprises a semi-static configuration of a list that indicates, for each of a plurality of cell identifiers (IDs) or QCL associations, whether or how for the UE to perform rate matching for NZP RS transmitted from that cell-ID or QCL association.