Methods and related devices for handling random access procedure in bandwidth part switching operation
A method for handling a Random Access (RA) procedure in the Bandwidth Part (BWP) switching operation includes: receiving, by a User Equipment (UE), Downlink Control Information (DCI) including a BWP switching indication via a Physical Downlink Control Channel (PDCCH) when the UE performs a first RA procedure on a first BWP; and performing, by the UE, at least one of a plurality of procedures in response to the BWP switching indication. The procedures include: stopping the first RA procedure on the first BWP and initiating a second RA procedure on a second BWP indicated by the BWP switching indication; and ignoring the BWP switching indication to continue with the first RA procedure.
1. A User Equipment (UE), comprising:
one or more non-transitory computer-readable media having computer-executable instructions embodied thereon; and
at least one processor coupled to the one or more non-transitory computer-readable media, and configured to execute the computer-executable instructions to:
receive a configuration of a first Bandwidth Part (BWP) through Radio Resource Control (RRC) signaling from a Base Station (BS);
initiate a Random Access (RA) procedure on the first BWP;
receive Downlink Control Information (DCI) indicating a BWP switching from the first BWP to a second BWP;
determine whether to switch to the second BWP in response to receiving the DCI;
in a case that the UE determines to switch to the second BWP:
stop the RA procedure that is ongoing on the first BWP;
determine whether the second BWP is configured with an RA resource; and
initiate, after determining that the second BWP is not configured with the RA resource, a new RA procedure on an initial BWP, the UE being informed of the initial BWP via system information received from the BS; and
in a case that the UE determines not to switch to the second BWP:
continue with the RA procedure that is ongoing on the first BWP; and
stop a BWP inactivity timer.
2. The UE of claim 1 , wherein the at least one processor is further configured to execute the computer-executable instructions to:
perform the new RA procedure on the initial BWP by using a group of RA parameters with configured values and using a group of UE variables with reset values.
3. The UE of claim 2 , wherein the group of UE variables comprises at least one of a preamble counter and a power ramping counter.
4. The UE of claim 1 , wherein the at least one processor is further configured to execute the computer-executable instructions to:
initiate the new RA procedure on the second BWP after determining that the second BWP is configured with the RA resource.
5. A method performed by a User Equipment (UE), the method comprising:
receiving a configuration of a first Bandwidth Part (BWP) through Radio Resource Control (RRC) signaling from a Base Station (BS);
initiating a Random Access (RA) procedure on the first BWP;
receiving Downlink Control Information (DCI) indicating a BWP switching from the first BWP to a second BWP;
determining whether to switch to the second BWP in response to receiving the DCI;
in a case that the UE determines to switch to the second BWP:
stopping the RA procedure that is ongoing on the first BWP;
determining whether the second BWP is configured with an RA resource; and
initiating, after determining that the second BWP is not configured with the RA resource, a new RA procedure on an initial BWP, the UE being informed of the initial BWP via system information received from the BS; and
in a case that the UE determines not to switch to the second BWP:
continuing with the RA procedure that is ongoing on the first BWP; and
stopping a BWP inactivity timer.
6. The method of claim 5 , further comprising:
performing the new RA procedure on the initial BWP by using a group of RA parameters with configured values and using a group of UE variables with reset values.
7. The method of claim 6 , wherein the group of UE variables comprises at least one of a preamble counter and a power ramping counter.
8. The method of claim 5 , further comprising:
initiating the new RA procedure on the second BWP after determining that the second BWP is configured with the RA resource.