US 12,114,365 B2
User apparatus, base station and communication system
Mitsuru Mochizuki, Tokyo (JP); Tadahiro Shimoda, Tokyo (JP); Noriyuki Fukui, Tokyo (JP); and Daichi Uchino, Tokyo (JP)
Assigned to Mitsubishi Electric Corporation, Tokyo (JP)
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
Filed on Feb. 2, 2023, as Appl. No. 18/163,582.
Application 18/163,582 is a continuation of application No. 17/259,782, abandoned, previously published as PCT/JP2019/030445, filed on Aug. 2, 2019.
Claims priority of application No. 2018-148621 (JP), filed on Aug. 7, 2018.
Prior Publication US 2023/0180304 A1, Jun. 8, 2023
Int. Cl. H04W 74/0833 (2024.01); H04W 56/00 (2009.01); H04W 74/00 (2009.01); H04W 76/34 (2018.01)
CPC H04W 74/0833 (2013.01) [H04W 56/0045 (2013.01); H04W 74/006 (2013.01); H04W 76/34 (2018.02)] 7 Claims
OG exemplary drawing
 
1. A user apparatus in a communication system comprising the user apparatus; and a plurality of base stations configured to wirelessly communicate with the user apparatus, the user apparatus comprising:
a processor communicating with the plurality of base stations,
wherein the plurality of base stations include a master node and a secondary node that support dual connectivity for the user apparatus,
the processor of the user apparatus receives from the master node Radio Resource Control (RRC) signaling including information related to usage of a split Signal Radio Bearer (SRB) or usage of an SRB3 in a procedure for adding or modifying the secondary node,
the processor of the user apparatus determines which of the split SRB and the SRB3 is configured,
in a case in which the split SRB is configured in a state of Master Cell Group (MCG) failure, the processor of the user apparatus transmits information related to the MCG failure to the master node via the secondary node using the split SRB, and receives an RRC Reconfiguration using the split SRB from the master node via the secondary node and
in a case in which the split SRB is not configured and the SRB3 is configured in a state of the MCG failure, the processor of the user apparatus transmits the information related to the MCG failure to the secondary node using the SRB3, and receives an RRC Reconfiguration from the secondary node using the SRB3.