Performing measurements on deactivated secondary cells
Methods, systems, and devices for wireless communication are described. Generally, the described techniques provide for efficiently performing measurements and other functions in preparation for communicating with a base station on a secondary cell (SCell). In particular, a user equipment (UE) may switch to a certain bandwidth part (BWP) (e.g., a dormant BWP) on an SCell when the SCell is deactivated, and the UE may perform the appropriate measurements and functions on this BWP (e.g., based on reference signals received on this BWP). In some cases, the UE may determine to switch to the BWP for performing the appropriate measurements and functions based on an inactivity timer expiring or based on an indication from a base station (e.g., on a primary cell (PCell)). Accordingly, once the UE activates the SCell for communications with a base station, the latency associated with preparing for communicating on the SCell may be reduced.
1. A method for wireless communication at a user equipment (UE), comprising:
communicating with a network entity on a first bandwidth part of a plurality of bandwidth parts on an active secondary cell;
switching from the first bandwidth part to a second dormant bandwidth part of the plurality of bandwidth parts on the active secondary cell for performing channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the active secondary cell; and
performing at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part on the active secondary cell.
2. The method of claim 1 , wherein switching from the first bandwidth part to the second dormant bandwidth part comprises:
receiving, on a primary cell or a primary secondary cell from the network entity, an indication to switch to the second dormant bandwidth part for performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading; and
switching from the first bandwidth part to the second dormant bandwidth part based at least in part on receiving the indication to switch to the second dormant bandwidth part.
3. The method of claim 1 , wherein switching from the first bandwidth part to the second dormant bandwidth part comprises:
autonomously switching from the first bandwidth part to the second dormant bandwidth part.
4. The method of claim 1 , further comprising:
determining that a measurement timer for performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part on the active secondary cell has expired; and
refraining from performing further channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part based at least in part on the measurement timer expiring.
5. The method of claim 4 , further comprising:
starting the measurement timer upon switching to the second dormant bandwidth part.
6. The method of claim 1 , further comprising:
receiving radio resource control signaling identifying the second dormant bandwidth part for performing the channel state measurements, beam management, automatic gain control maintenance, or master information block reading.
7. The method of claim 6 , wherein the radio resource control signaling further indicates a configuration for performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part.
8. The method of claim 7 , wherein the configuration indicates a periodicity for performing at least one of the channel state measurements or the beam management.
9. The method of claim 1 , further comprising:
receiving a synchronization signal block or a channel state information reference signal on the second dormant bandwidth part after switching to the second dormant bandwidth part; and
performing the channel state measurements, beam management, automatic gain control maintenance, or master information block reading based at least in part on the synchronization signal block or the channel state information reference signal.
10. The method of claim 1 , wherein the first bandwidth part comprises a dedicated bandwidth part.
11. The method of claim 1 , further comprising:
determining that the UE is capable of performing channel state measurements, beam management, automatic gain control maintenance, and master information block reading on the second dormant bandwidth part on the active secondary cell; and
performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part on the active secondary cell based at least in part on the determining.
12. A method for wireless communication at a network entity, comprising:
communicating with a user equipment (UE) on a first bandwidth part of a plurality of bandwidth parts on an active secondary cell; and
transmitting, to the UE on a primary cell or a primary secondary cell, an indication for the UE to switch to a second dormant bandwidth part of the plurality of bandwidth parts for performing at least one of channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the active secondary cell.
13. The method of claim 12 , further comprising:
transmitting radio resource control signaling identifying the second dormant bandwidth part on which the UE is to perform the channel state measurements, beam management, automatic gain control maintenance, or master information block reading.
14. The method of claim 13 , wherein the radio resource control signaling further indicates a configuration for performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part.
15. The method of claim 14 , wherein the configuration indicates a periodicity for performing at least one of the channel state measurements or the beam management.
16. A user equipment (UE), comprising:
one or more memories storing processor-executable code; and
one or more processors coupled with the one or more memories and
individually or collectively operable to execute the code to cause the UE to:
communicate with a network entity on a first bandwidth part of a plurality of bandwidth parts on an active secondary cell;
switch from the first bandwidth part to a second dormant bandwidth part of the plurality of bandwidth parts for performing channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the active secondary cell; and
perform at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part on the active secondary cell.
17. A network entity, comprising:
one or more memories storing processor-executable code; and
one or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the network entity to:
communicate with a user equipment (UE) on a first bandwidth part of a plurality of bandwidth parts on an active secondary cell; and
transmit, to the UE on a primary cell or a primary secondary cell, an indication for the UE to switch to a second dormant bandwidth part of the plurality of bandwidth parts for performing at least one of channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the active secondary cell.
18. The UE of claim 16 , wherein, to switch from the first bandwidth part to the second dormant bandwidth part, the one or more processors are individually or collectively operable to execute the code to cause the UE to:
receive, on a primary cell or a primary secondary cell from the network entity, an indication to switch to the second dormant bandwidth part for performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading; and
switch from the first bandwidth part to the second dormant bandwidth part based at least in part on receiving the indication to switch to the second dormant bandwidth part.
19. The UE of claim 16 , wherein, to switch from the first bandwidth part to the second dormant bandwidth part, the one or more processors are individually or collectively operable to execute the code to cause the UE to:
autonomously switch from the first bandwidth part to the second dormant bandwidth part.
20. The UE of claim 16 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the UE to:
determine that a measurement timer for performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part on the active secondary cell has expired; and
refrain from performing further channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part based at least in part on the measurement timer expiring.
21. The UE of claim 20 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the UE to:
start the measurement timer upon switching to the second dormant bandwidth part.
22. The UE of claim 16 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the UE to:
receive radio resource control signaling identifying the second dormant bandwidth part for performing the channel state measurements, beam management, automatic gain control maintenance, or master information block reading.
23. The UE of claim 22 , wherein the radio resource control signaling further indicates a configuration for performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part.
24. The UE of claim 23 , wherein the configuration indicates a periodicity for performing at least one of the channel state measurements or the beam management.
25. The UE of claim 16 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the UE to:
receive a synchronization signal block or a channel state information reference signal on the second dormant bandwidth part after switching to the second dormant bandwidth part; and
perform the channel state measurements, beam management, automatic gain control maintenance, or master information block reading based at least in part on the synchronization signal block or the channel state information reference signal.
26. The UE of claim 16 , wherein the first bandwidth part comprises a dedicated bandwidth part.
27. The UE of claim 16 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the UE to:
determine that the UE is capable of performing channel state measurements, beam management, automatic gain control maintenance, and master information block reading on the second dormant bandwidth part on the active secondary cell; and
perform the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part on the active secondary cell based at least in part on the determining.
28. The network entity of claim 17 , wherein the one or more processors are individually or collectively further operable to execute the code to cause the network entity to:
transmit radio resource control signaling identifying the second dormant bandwidth part on which the UE is to perform the channel state measurements, beam management, automatic gain control maintenance, or master information block reading.
29. The network entity of claim 28 , wherein the radio resource control signaling further indicates a configuration for performing the at least one of the channel state measurements, beam management, automatic gain control maintenance, or master information block reading on the second dormant bandwidth part.
30. The network entity of claim 29 , wherein the configuration indicates a periodicity for performing at least one of the channel state measurements or the beam management.