Systems and methods for QCL-typed collision handling
A UE may receive multiple signals causing a Quasi co-location TypeD (QCL-TypeD) collision. To determine which of the multiple signals to select, the UE may use a certain option based on a type transmission scheme associated with each of the multiple signals. The options may include one of a priority rule for signal reception, a scheduling restriction, or a priority rule for QCL-TypeD selection.
1. A method for a user equipment (UE), comprising:
receiving multiple signals causing a Quasi co-location TypeD (QCL-TypeD) collision, wherein the multiple signals are configured in one of two transmission schemes, wherein the two transmission schemes comprise a first transmission scheme type where the signals are transmitted in a single frequency network (SFN) manner and a second transmission scheme type where the signals are transmitted in a non-SFN manner within a band or band group and overlapped in time domain, and where two Transmission Configuration Indicator (TCI) States are applicable for PDCCH;
determining which of the multiple signals to receive based on whether a type of transmission scheme associated with each of the multiple signals uses the SFN manner or the non-SFN manner and one of a signal reception priority rule, a scheduling restriction, or a QCL-TypeD selection priority rule;
selecting one or more highest priority Search Spaces (SSs) based on the signal reception priority rule or the QCL-TypeD selection priority rule, wherein when two SSs are selected with the two TCI states, other normal PDCCH Quasi co-located with one of the two TCI States are also selected; and
processing a received signal from the one or more highest priority SSs and the other normal PDCCH Quasi co-located with one of the two TCI States based on which of the multiple signal are determined to be received based on the type of transmission scheme associated with each of the multiple signals and one of the signal reception priority rule, the scheduling restriction, or the QCL-TypeD selection priority rule.
2. The method of claim 1 , wherein determining which of the multiple signals to receive comprises using one or both TCI States applied for Physical Downlink Control Channel (PDCCH) for Physical Downlink Shared Channel (PDSCH) reception.
3. The method of claim 2 , further comprising receiving an RRC parameter indicating whether one or two TCI states applied for PDCCH will be used for PDSCH reception.
4. The method of claim 1 wherein to determine which of the multiple signals to receive, the QCL-TypeD for one of the TCI States applied for PDCCH is the same as the QCL-TypeD configured for Channel-State Information Reference Signal (CSI-RS) with repetition equal to off.
5. The method of claim 1 , wherein to determine which of the multiple signals to receive, the QCL-TypeD for one of search spaces or Control Resource Sets (CORESETs) for PDCCH is the same as the QCL-TypeD configured for CSI-RS with repetition equal to off.
6. The method of claim 1 , wherein to determine which of the multiple signals to receive, one of the TCI States applied for PDCCH is used for aperiodic CSI-RS reception.
7. The method of claim 6 , wherein whether to select a first or a second TCI is indicated by scheduling Downlink Control Information (DCI).
8. The method of claim 1 , wherein to determine which of the multiple signals to receive, a source RS to provide QCL-TypeD indication for at least one of the TCI States applied for PDSCH is QCL-ed with SSB with QCL-TypeD.
9. The method of claim 1 , wherein to determine which of the multiple signals to receive, a priority from the signal reception priority rule or the QCL-TypeD selection priority rule is determined by search space type, search space index, component carrier index as well as a number of TCI States in a CORESET,
wherein if a selected CORESET has two TCI States, other normal PDCCH QCLed with one of the two TCI States can be selected.
10. The method of claim 1 , wherein to determine which of the multiple (Original) signals to receive, a priority from the signal reception priority rule or the QCL-TypeD selection priority rule can be determined per TCI States pair.
11. A user equipment (UE) comprising:
a baseband processing unit; and
a memory storing instructions that, when executed by the baseband processing unit, configure the UE to:
receive multiple signals causing a Quasi co-location TypeD (QCL-TypeD) collision, wherein the multiple signals are configured in one of two transmission schemes, wherein the two transmission schemes comprise a first transmission scheme type where the signals are transmitted in a single frequency network (SFN) manner and a second transmission scheme type where the signals are transmitted in a non-SFN manner within a band or band group and overlapped in time domain, and where two Transmission Configuration Indicator (TCI) States can be applied for PDCCH;
determine which of the multiple signals to receive based on whether a type transmission scheme associated with each of the multiple signals uses the SFN manner or the non-SFN manner and one of a signal reception priority rule, a scheduling restriction, or a QCL-TypeD selection priority rule;
select one or more highest priority Search Spaces (SSs) based on the signal reception priority rule or the QCL-TypeD selection priority rule, wherein when two SSs are selected with the two TCI states, other normal PDCCH Quasi co-located with one of the two TCI States are also selected; and
process a received signal from the one or more highest priority SSs and the other normal PDCCH Quasi co-located with one of the two TCI States based on which of the multiple signal are determined to be received based on the type of transmission scheme associated with each of the multiple signals and one of the signal reception priority rule, the scheduling restriction, or the QCL-TypeD selection priority rule.
12. The UE of claim 11 , wherein determining which of the multiple signals to receive comprises use one or both TCI States applied for Physical Downlink Control Channel (PDCCH) for Physical Downlink Shared Channel (PDSCH) reception.
13. The UE of claim 12 , wherein the instructions further configure the UE to receive an RRC parameter indicating whether one or two TCI states applied for PDCCH will be used for PDSCH reception.
14. The UE of claim 11 wherein to determine which of the multiple signals to receive, the QCL-TypeD for one of the TCI States applied for PDCCH should be the same as the QCL-TypeD configured for Channel-State Information Reference Signal (CSI-RS) with repetition equal to off.
15. The UE of claim 11 , wherein to determine which of the multiple signals to receive, the QCL-TypeD for one of search spaces or CORESETs for PDCCH is the same as the QCL-TypeD configured for CSI-RS with repetition equal to off.
16. The UE of claim 11 , wherein to determine which of the multiple signals to receive, one of the TCI States applied for PDCCH is used for aperiodic CSI-RS reception.
17. The UE of claim 11 , whether to select a first or a second TCI is indicated by scheduling Downlink Control Information (DCI).
18. The UE of claim 11 , wherein to determine which of the multiple signals to receive, a source RS to provide QCL-TypeD indication for at least one of the TCI States applied for PDSCH is QCL-ed with SSB with QCL-TypeD.
19. The UE of claim 11 wherein to determine which of the multiple signals to receive, a priority from the signal reception priority rule or the QCL-TypeD selection priority rule is determined by search space type, search space index, component carrier index as well as a number of TCI States in a CORESET, wherein if a selected CORESET has two TCI States, other normal PDCCH QCLed with one of the two TCI States can be selected.
20. The UE of claim 11 , wherein to determine which of the multiple signals to receive, a priority from the signal reception priority rule or the QCL-TypeD selection priority rule can be determined per TCI States pair.