Device and method for transmitting state information in wireless communication system
The present disclosure relates to a pre-5 th -Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4 th -Generation (4G) communication system such as Long Term Evolution (LTE). According to various embodiments of the present disclosure, a method for operating a user equipment (UE) supporting carrier aggregation (CA) with a master cell group (MCG) and a secondary cell group (SCG) in a wireless communication system is provided. The method comprising: detecting a radio link failure (RLF) of the MCG; when the RLF of the MCG is detected, determining whether a transmission to the SCG is suspended; and when the transmission to the SCG is determined to be suspended, initiating a connection re-establishment procedure.
1 . A method performed by a user equipment (UE) in a wireless communication system, the method comprising:
detecting a radio link failure for a master cell group (MCG);
resetting an MCG medium access control (MAC);
determining that a secondary cell group (SCG) transmission is not suspended for signaling radio bearers (SRBs); and
based on determining that the SCG transmission is not suspended for SRBs:
stopping at least one running timer;
suspending an MCG transmission for all SRBs and data radio bearers (DRBs) except for a signaling radio bearer 0 (SRB0); and
transmitting MCG failure information to a secondary base station via a split SRB1 or an SRB3,
wherein, if the split SRB1 is configured for the UE, a primary path of the split SRB1 is the MCG, and an uplink data split threshold is not zero, the MCG failure information is transmitted to the secondary base station via the split SRB1 by setting the primary path to refer to the SCG and setting the uplink data split threshold temporarily to zero, and
wherein, if the SRB3 is configured for the UE, the MCG failure information is transmitted to the secondary base station via the SRB3.
2 . The method of claim 1 , further comprising:
if the SCG transmission is suspended, performing a connection re-establishment procedure.
3 . The method of claim 1 , wherein the radio link failure for the MCG is detected based on at least one of a T310 timer expiry, a random access problem indication, or a reaching a maximum number of retransmissions of radio link control (RLC).
4 . A user equipment (UE) comprising:
at least one transceiver;
at least one processor communicatively coupled to the at least one transceiver;
at least one memory, communicatively coupled to the at least one processor, storing instructions executable by the at least one processor individually or in any combination to cause the UE to:
detect a radio link failure for a master cell group (MCG),
reset an MCG medium access control (MAC),
determine that a secondary cell group (SCG) transmission is not suspended for signaling radio bearers (SRBs), and
based on determining that the SCG transmission is not suspended for SRBs:
stop at least one running timer,
suspend an MCG transmission for all SRBs and data radio bearers (DRBs) except for a signaling radio bearer 0 (SRB0), and
transmit MCG failure information to a secondary base station via a split SRB1 or an SRB3,
wherein, if the split SRB1 is configured for the UE, a primary path of the split SRB1 is the MCG, and an uplink data split threshold is not zero, the MCG failure information is transmitted to the secondary base station via the split SRB1 by setting the primary path to refer to the SCG and setting the uplink data split threshold temporarily to zero, and
wherein, if the SRB3 is configured for the UE, the MCG failure information is transmitted to the secondary base station via the SRB3.
5 . The UE of claim 4 , wherein the instructions further cause the UE to:
if the SCG transmission is suspended, perform a connection re-establishment procedure.
6 . The UE of claim 4 , wherein the radio link failure for the MCG is detected based on at least one of a T310 timer expiry, a random access problem indication, or a reaching a maximum number of retransmissions of radio link control (RLC).