JPWO2020222904A5

JPWO2020222904A5 -

Info

Publication number: JPWO2020222904A5
Application number: JP2021564342A
Authority: JP
Publication date: 2023-02-20

Claims

A method for wireless communication in a user equipment (UE), comprising:
one or more target base stations, one or more measurement thresholds for triggering handover from a source base station to said one or more target base stations, and said one or more target base stations. receiving a conditional handover configuration from said source base station indicating one or more timers associated with said handover to a a step comprising
determining based at least in part on the conditional handover configuration that a first measurement threshold for initiating the handover to a first target base station is met;
sending a first random access request based at least in part on the conditional handover configuration to the first target to initiate a first random access procedure for the handover to the first target base station; transmitting to a base station;
starting the first conditional handover timer for completing the first random access procedure in response to the transmission of the first random access request;
determining a first conditional handover failure in response to expiration of said first conditional handover timer prior to completing said first random access procedure.

2. The method of claim 1, wherein the conditional handover configuration comprises at least a first conditional handover configuration for the first target base station and a second conditional handover configuration for a second target base station. .

sending a second random access request in response to expiration of the first conditional handover timer to the second target base station to initiate a second random access procedure for the handover to the second target base station; transmitting to a target base station;
2. The method of claim 1, further comprising: starting a second conditional handover timer for completing the second random access procedure.

4. The method of claim 3 , further comprising initiating a connection re-establishment procedure upon determining that no other target base station is configured for conditional handover.

4. The method of claim 3 , wherein a first duration of said first conditional handover timer is different than a second duration of said second conditional handover timer.

from the plurality of available target base stations based at least in part on channel quality measurements associated with each of the plurality of available target base stations in response to expiration of the first conditional handover timer. 4. The method of claim 3 , further comprising: selecting the second target base station.

2. The method of claim 1, further comprising initiating a connection re-establishment procedure in response to expiration of the first conditional handover timer.

receiving a deconfiguration message from the source base station deconfiguring one or more conditional handover configurations;
2. The method of claim 1, further comprising: deconfiguring the one or more conditional handover configurations based at least in part on the deconfiguration message.

9. The method of claim 8 , wherein the deconfiguration message is received in radio resource control signaling from the source base station.

deleting one or more of the radio resource control configuration or the first measurement and the reporting configuration for the conditional handover trigger provided in the first conditional handover configuration;
9. The method of claim 8 , further comprising: suspending conditional handover measurements associated with the conditional handover configuration and evaluation of whether the measurements satisfy conditional handover criteria.

1. An apparatus for wireless communication in a user equipment (UE), comprising:
one or more target base stations, one or more measurement thresholds for triggering handover from a source base station to said one or more target base stations, and said one or more target base stations. means for receiving a conditional handover configuration from the source base station indicative of one or more timers associated with the handover to at least a first conditional means including a handover timer ;
means for determining based at least in part on the conditional handover configuration that a first measurement threshold for initiating the handover to a first target base station is met;
sending a first random access request based at least in part on the conditional handover configuration to the first target to initiate a first random access procedure for the handover to the first target base station; means for transmitting to a base station;
means for starting the first conditional handover timer for completing the first random access procedure in response to the transmission of the first random access request;
means for determining a first conditional handover failure in response to expiration of said first conditional handover timer prior to completing said first random access procedure.

sending a second random access request in response to expiration of the first conditional handover timer to the second target base station to initiate a second random access procedure for the handover to the second target base station; means for transmitting to a target base station;
12. The apparatus of claim 11 , further comprising: means for starting a second conditional handover timer for completing said second random access procedure.

12. The apparatus of claim 11 , further comprising: means for activating a connection re-establishment procedure in response to expiration of said first conditional handover timer.

means for receiving a deconfiguration message from the source base station deconfiguring one or more conditional handover configurations;
12. The apparatus of claim 11 , further comprising: means for deconfiguring said one or more conditional handover configurations based at least in part on said deconfiguration message.

the deconfiguration message is received from the source base station in radio resource control signaling, and the apparatus:
means for deleting one or more of the radio resource control configuration or the first measurement and the reporting configuration for the conditional handover trigger provided in the first conditional handover configuration;
means for discontinuing conditional handover measurements associated with said conditional handover configuration and evaluation of whether said measurements satisfy conditional handover criteria;
15. Apparatus according to claim 14 .