Method and apparatus for reestablishment and mobility optimization (MRO) in a wireless communication system
Embodiments of the present disclosure relate to methods and apparatuses for reestablishment in a wireless communication system. According to some embodiments of the present disclosure, a method includes: receiving, at a user equipment (UE) from a first base station (BS), conditional reestablishment configuration information indicating a set of execution conditions for a set of candidate cells; and evaluating the set of execution conditions based on the conditional reestablishment configuration information in response to the reception of conditional reestablishment configuration information. The leaving indication is sent to the serving cell in response to the initiation of the conditional reestablishment. The RLF report is reported in response to the failure of conditional reestablishment or an RLF event when the conditional reestablishment is configured.
1 . An apparatus for wireless communication, comprising:
at least one memory; and
at least one processor coupled with the at least one memory and configured to cause the apparatus to:
transmit a measurement report to a first base station (BS);
receive, from a cell of the first BS, a command to perform a conditional reestablishment procedure and conditional reestablishment configuration information indicating a set of execution conditions for a set of candidate cells for the conditional reestablishment procedure; and
evaluate the set of execution conditions for the set of candidate cells based on the conditional reestablishment configuration information in response to the reception of the conditional reestablishment configuration information; and
initiate the conditional reestablishment procedure in response to a first candidate cell of the set of candidate cells satisfying a reestablishment condition.
2 . The apparatus of claim 1 , wherein the at least one processor is further configured to cause the apparatus to:
stop evaluating the set of execution conditions in response to the first candidate cell of the set of candidate cells satisfying the reestablishment condition.
3 . The apparatus of claim 1 , wherein the at least one processor is further configured to cause the apparatus to:
transmit a radio resource control (RRC) message to the first BS in response to the initiation of the conditional reestablishment procedure, wherein the RRC message comprises an indicator indicating that the UE is leaving the first BS and an identity of the first candidate cell.
4 . The apparatus of claim 1 , wherein the at least one processor is further configured to cause the apparatus to:
transmit a radio resource control (RRC) message to the first BS in response to a first candidate cell of the set of candidate cells satisfying a reestablishment condition, wherein the RRC message comprises an indicator indicating that the UE is leaving the first BS and an identity of the first candidate cell.
5 . The apparatus of claim 1 , wherein the at least one processor is further configured to cause the apparatus to:
release the conditional reestablishment configuration information in response to successfully accessing the first candidate cell.
6 . The apparatus of claim 1 , wherein the at least one processor is further configured to cause the apparatus to:
enter an idle mode in response to a failure of the conditional reestablishment procedure.
7 . The apparatus of claim 1 , wherein the at least one processor is further configured to cause the apparatus to:
declare a radio link failure (RLF) at the apparatus before any candidate cell satisfies a reestablishment condition.
8 . An apparatus for wireless communication, comprising:
at least one memory; and
at least one processor coupled with the at least one memory and configured to cause the apparatus to:
transmit a measurement report;
receive a reestablishment command that includes:
a command to perform a conditional reestablishment procedure; and
conditional reestablishment configuration information indicating a set of execution conditions for a set of candidate cells for the conditional reestablishment procedure; and
initiate the reestablishment procedure in response to the reception of the reestablishment command.
9 . The apparatus of claim 8 , wherein the at least one processor is further configured to cause the apparatus to:
not start a timer associated with the reestablishment initiation.
10 . The apparatus of claim 8 , wherein the at least one processor is further configured to cause the apparatus to:
select a target cell from the set of candidate cells.
11 . The apparatus of claim 10 , wherein a channel quality between the apparatus and the target cell is a best channel quality for channel qualities between the apparatus and the set of candidate cells.
12 . The apparatus of claim 8 , wherein the at least one processor is further configured to cause the apparatus to:
stop evaluating the configuration for the conditional reestablishment in response to the reception of the reestablishment command.
13 . The apparatus of claim 8 , wherein the at least one processor is further configured to cause the apparatus to:
release the configuration for the conditional reestablishment in response to the reception of the reestablishment command.
14 . A method performed by an apparatus for wireless communication, the metho comprising:
transmitting a measurement report to a first base station (BS);
receiving, from a cell of the first BS, a command to perform a conditional reestablishment procedure and conditional reestablishment configuration information indicating a set of execution conditions for a set of candidate cells for the conditional reestablishment procedure; and
evaluating the set of execution conditions for the set of candidate cells based on the conditional reestablishment configuration information in response to the reception of the conditional reestablishment configuration information; and
initiating the conditional reestablishment procedure in response to a first candidate cell of the set of candidate cells satisfying a reestablishment condition.
15 . The method of claim 14 , further comprising:
stopping evaluating the set of execution conditions in response to the first candidate cell of the set of candidate cells satisfying the reestablishment condition.
16 . The method of claim 14 , further comprising:
transmitting a radio resource control (RRC) message to the first BS in response to the initiation of the conditional reestablishment procedure, wherein the RRC message comprises an indicator indicating that the UE is leaving the first BS and an identity of the first candidate cell.
17 . The method of claim 14 , further comprising:
transmitting a radio resource control (RRC) message to the first BS in response to a first candidate cell of the set of candidate cells satisfying a reestablishment condition, wherein the RRC message comprises an indicator indicating that the UE is leaving the first BS and an identity of the first candidate cell.
18 . The method of claim 14 , further comprising:
releasing the conditional reestablishment configuration information in response to successfully accessing the first candidate cell.
19 . The method of claim 14 , further comprising:
entering an idle mode in response to a failure of the conditional reestablishment procedure.