Methods and systems for beam tracking process management and indices
In a multi-BPL scenario, some form of beam-related indication is desirable to provide assistance to the UE in setting its Rx spatial filtering configuration to receive PDSCH. The assistance to the UE is in the form of a certain indicator indicating a spatial QCL assumption between PDSCH DMRS antenna port(s) and DL RS (e.g., CSI-RS) antenna port(s), such as a preferred CSI-RS resource that was measured and reported previously.
1. A method performed by a transmission point (TRP) for communicating with a user equipment (UE), the method comprising:
transmitting, to the UE, a first message comprising multiple CSI-RS configurations and a first beam tracking process index (BTPI), wherein the first BTPI identifies a first beam tracking process;
transmitting, to the UE, a trigger message for triggering the UE to transmit an aperiodic measurement report with respect to a set of one or more CSI-RS resources of the CSI-RS configurations;
receiving, from the UE, the aperiodic measurement report comprising an identification of a preferred CSI-RS configuration, and
transmitting, to the UE, a control message for scheduling a PDSCH transmission, wherein the first BTPI is included in the control message.
2. The method of claim 1 , wherein
the first beam tracking process is associated with a first link between the TRP and the UE, and
the first link between the TRP and the UE is an active link used for transmitting control information and user data.
3. The method of claim 1 , further comprising:
transmitting, to the UE, a second message comprising multiple CSI-RS configurations and a second BTPI that identifies a second beam tracking process.
4. The method of claim 3 , wherein
the second BTPI is associated with a second link between the TRP and the UE, and
the second link between the TRP and the UE is a monitored link.
5. The method of claim 1 , wherein the control message is transmitted after the trigger message.
6. The method of claim 1 , wherein the trigger message is a trigger message for triggering the UE to perform aperiodic CSI-RS measurements with respect to the set of one or more RS resources.
7. The method of claim 1 , wherein
the first message is a radio resource control (RRC) message.
8. The method of claim 1 , wherein
the first BTPI is associated with a transmit spatial filtering configuration, and
the method further comprises performing the PDSCH transmission using the transmit spatial filtering configuration associated with the first BTPI.
9. The method of claim 1 , wherein the trigger message comprises the first BTPI.
10. The method of claim 1 , further comprising:
after transmitting the trigger message to the UE and before transmitting the control message to the UE, transmitting to the UE a message comprising the BTPI, wherein
the BTPI is not included in the trigger message.
11. The method of claim 1 , wherein
the trigger message is a report trigger message for triggering the UE to transmit at least one measurement report after performing the RS measurements.
12. A transmission point (TRP) for communicating with a user equipment (UE), the TRP comprising:
at least one processor; and
a memory, the memory comprising instructions executable by the at least one processor, wherein the TRP is configured to perform a method comprising:
transmitting, to the UE, a first message comprising multiple CSI-RS configurations and a first beam tracking process index (BTPI), wherein the first BTPI identifies a first beam tracking process;
transmitting, to the UE, a trigger message for triggering the UE to transmit an aperiodic measurement report with respect to a set of one or more CSI-RS resources of the CSI-RS configurations;
receiving, from the UE, the aperiodic measurement report comprising an identification of a preferred CSI-RS configuration, and
transmitting, to the UE, a control message for scheduling a PDSCH transmission, wherein the first BTPI is included in the control message.
13. A method performed by a user equipment (UE) communicating with a transmission point (TRP), the method comprising:
receiving, from the TRP, a first message comprising multiple CSI-RS configurations and a first beam tracking process index (BTPI) wherein the first BTPI identifies a first beam tracking process;
receiving, from the TRP, a trigger message for triggering the UE to transmit an aperiodic measurement report with respect to a set of one or more CSI-RS resources of the configured CSI-RS configurations to the TRP;
determining a preferred CSI-RS configuration from the configured CSI-RS configurations;
transmitting, to the TRP, the aperiodic measurement report comprising an identification of the preferred CSI-RS configuration, and
receiving, from the TRP, a control message for scheduling a PDSCH transmission, wherein the first BTPI is included in the control message.
14. The method of claim 13 , wherein
first beam tracking process is associated with a first link between the TRP and the UE, and
the first link between the TRP and the UE is an active link used for transmitting control information and user data.
15. The method of claim 13 , further comprising:
receiving, from the TRP, a second message comprising multiple CSI-RS configurations and a second BTPI that identifies a second beam tracking process.
16. The method of claim 15 , wherein
the second BTPI is associated with a second link between the TRP and the UE, and
the second link between the TRP and the UE is a monitored link.
17. The method of claim 13 , further comprising:
determining, based at least in part on the one or more CSI-RS configurations, a set of one or more UE receive beam parameters; and
storing, together with the first BTPI, the one or more UE receive beam parameters.
18. The method of claim 13 , further comprising:
after receiving the control message, using the first BTPI to determine a spatial filtering configuration associated with the first BTPI; and
after determining the spatial filtering configuration, using the spatial filtering configuration to receive the PDSCH transmission.
19. The method of claim 13 , wherein
wherein the control message is received after the trigger message.
20. The method of claim 13 , wherein
wherein the trigger message is a trigger message for triggering the UE to perform CSI-RS measurements with respect to the set of one or more RS resources.
21. The method of any one of claim 13 , wherein
the preferred CSI-RS configuration is determined using received reference signal received power (RSRP).
22. The method of claim 21 , further comprising:
after receiving the trigger message and before receiving the control message, receiving a message comprising the BTPI, wherein
the BTPI is not included in the trigger message.
23. The method of claim 13 , wherein the message comprising the multiple CSI-RS configurations is a radio resource control (RRC) message.
24. The method of claim 13 , wherein
the trigger message is a report trigger message for triggering the UE to transmit at least one measurement report after performing the RS measurements.
25. A user equipment (UE) for communicating with a transmission point (TRP), the UE comprising at least one processor; and a memory, the memory comprising instructions executable by the at least one processor, wherein the UE is configured to perform a method comprising:
receiving, from the TRP, a first message comprising multiple CSI-RS configurations and a first beam tracking process index (BTPI) wherein the first BTPI identifies a first beam tracking process;
receiving, from the TRP, a trigger message for triggering the UE to transmit an aperiodic measurement report with respect to a set of one or more CSI-RS resources of the configured CSI-RS configurations to the TRP;
determining a preferred CSI-RS configuration from the configured CSI-RS configurations;
transmitting, to the TRP, the aperiodic measurement report comprising an identification of the preferred CSI-RS configuration, and
receiving, from the TRP, a control message for scheduling a PDSCH transmission, wherein the first BTPI is included in the control message.