Channel state information (CSI) measurement with different quasi-colocation (QCL) configurations for a same CSI reference signal (CSI-RS) resource
Certain aspects of the present disclosure relate to methods and apparatus for providing quasi-colocation (QCL) signaling for reference signals (RS) and channels across scenarios involving multiple cells, such as coordinated multipoint (CoMP) scenarios in which multiple transmit receive points (TRPs) or integrated access and backhaul (IAB) nodes each have their own cell ID.
1. A method for wireless communications by a user equipment (UE), comprising:
obtaining a channel state information (CSI) reporting configuration indicating different quasi-colocation (QCL) assumptions for a common reference signal (RS) resource included in at least first and second resource sets;
detecting aperiodic CSI report triggering states indicating a first slot offset for the first resource set and a second slot offset for the second resource set;
determining if the CSI reporting configuration is valid or invalid, based on at least one condition; and
sending a CSI report for at least one of the first resource set or the second resource set, in accordance with the determination.
2. The method of claim 1 , wherein information regarding the QCL assumptions is indicated via transmission configuration information (TCI) states.
3. The method of claim 1 , wherein the at least one condition is based on whether the aperiodic CSI reporting states result in the first and second resource sets occurring in the same slot for CSI measurement.
4. The method of claim 3 , wherein the UE is configured to determine the CSI reporting configuration is invalid if CSI reporting for the first and second resource sets is triggered in different slots, but the first slot offset and second slot offset result in the common RS resource occurring on a same symbol.
5. The method of claim 1 , wherein:
the first slot offset and second slot offset result in the common RS resource occurring on different symbols; and
the at least one condition is based on a time gap between the different symbols.
6. The method of claim 5 , wherein the UE is configured to determine the CSI reporting configuration is invalid if the time gap between the different symbols is below a timing threshold.
7. The method of claim 6 , wherein the timing threshold is specified in units of OFDM symbols or slots.
8. The method of claim 6 , wherein the UE determines the timing threshold based on a configuration from a base station or based on a fixed value.
9. The method of claim 6 , wherein the timing threshold is determined, at least in part, by QCL types of the first and second resource sets.
10. The method of claim 9 , wherein:
a first timing threshold is used if a QCL type of at least one of the first or second resource sets contains spatial information; or
a second timing threshold is used if a QCL type of at least one of the first or second resource sets does not contain spatial information.
11. The method of claim 6 , wherein the timing threshold is determined by at least one of:
a number of ports of each of the first and second resource set; or
a report quantity of CSI reports for the first and second resource sets.
12. The method of claim 6 , wherein:
a number of ports of each of the first and second resource set and a report quantity of the CSI reports for the first and second resource sets determines a number of processing units of each of the CSI reports; and
the timing threshold is determined, at least in part, by the number of processing units of at least one of the first or second CSI reports.
13. The method of claim 5 , wherein the UE is configured to apply a priority rule to drop or refrain from updating a CSI report for one of the resource sets if the UE determines the CSI reporting configuration is invalid because the time gap between the different symbols is below a timing threshold.
14. The method of claim 13 , wherein the priority rule is determined based on at least one of a type of the CSI report, a report quantity, a serving cell ID, or a report ID.
15. A method for wireless communications by a network entity, comprising:
configuring a user equipment (UE) with a channel state information (CSI) reporting configuration indicating different quasi-colocation (QCL) assumptions for a common reference signal (RS) resource included in at least first and second resource sets;
triggering aperiodic CSI reports via triggering states indicating a first slot offset for the first resource set and a second slot offset for the second resource set;
determining if the CSI reporting configuration is valid or invalid, based on at least one condition; and
receiving a CSI report for at least one of the first resource set or the second resource set, in accordance with the determination.
16. The method of claim 15 , wherein information regarding the QCL assumptions is indicated via transmission configuration information (TCI) states.
17. The method of claim 15 , wherein the at least one condition is based on whether the aperiodic CSI reporting states result in the first and second resource sets occurring in the same slot for CSI measurement.
18. The method of claim 17 , wherein determining the CSI reporting configuration is invalid if CSI reporting for the first and second resource sets is triggered in different slots, but the first slot offset and second slot offset result in the common RS resource occurring on a same symbol.
19. The method of claim 15 , wherein:
the first slot offset and second slot offset result in the common RS resource occurring on different symbols; and
the at least one condition is based on a time gap between the different symbols.
20. The method of claim 19 , wherein determining the CSI reporting configuration is invalid if the time gap between the different symbols is below a timing threshold.
21. The method of claim 20 , wherein the timing threshold is specified in units of OFDM symbols or slots.
22. The method of claim 20 , wherein configuring the UE the timing threshold or determining the threshold as a fixed value.
23. The method of claim 20 , wherein the timing threshold is determined, at least in part, by QCL types of the first and second resource sets.
24. The method of claim 23 , wherein:
a first timing threshold is used if a QCL type of at least one of the first or second resource sets contains spatial information; or
a second timing threshold is used if a QCL type of at least one of the first or second resource sets does not contain spatial information.
25. The method of claim 20 , wherein the timing threshold is determined by at least one of:
a number of ports of each of the first and second resource set; or
a report quantity of CSI reports for the first and second resource sets.
26. The method of claim 20 , wherein:
a number of ports of each of the first and second resource set and a report quantity of the CSI reports for the first and second resource sets determines a number of processing units of each of the CSI reports; and
the timing threshold is determined, at least in part, by the number of processing units of at least one of the first or second CSI reports.
27. The method of claim 19 , wherein based on a priority rule, the BS determines that a CSI report for one of the resource sets is dropped or not updated if the determining the CSI reporting configuration is invalid because the time gap between the different symbols is below a timing threshold.
28. The method of claim 27 , wherein the priority rule is determined based on at least one of a type of the CSI report, a report quantity, a serving cell ID, or a report ID.
29. An apparatus for wireless communications by a user equipment (UE), comprising:
means for obtaining a channel state information (CSI) reporting configuration indicating different quasi-colocation (QCL) assumptions for a common reference signal (RS) resource included in at least first and second resource sets;
means for detecting aperiodic CSI report triggering states indicating a first slot offset for the first resource set and a second slot offset for the second resource set;
means for determining if the CSI reporting configuration is valid or invalid, based on at least one condition; and
means for sending a CSI report for at least one of the first resource set or the second resource set, in accordance with the determination.
30. An apparatus for wireless communications by a network entity, comprising:
means for configuring a user equipment (UE) with a channel state information (CSI) reporting configuration indicating different quasi-colocation (QCL) assumptions for a common reference signal (RS) resource included in at least first and second resource sets;
means for triggering aperiodic CSI reports via triggering states indicating a first slot offset for the first resource set and a second slot offset for the second resource set;
means for determining if the CSI reporting configuration is valid or invalid, based on at least one condition; and
means for receiving a CSI report for at least one of the first resource set or the second resource set, in accordance with the determination.