US-12621896-B2 - Device and method for transmitting state information in wireless communication system

US12621896B2US 12621896 B2US12621896 B2US 12621896B2US-12621896-B2

Abstract

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.

Inventors

Sangkyu BAEK
Hyunjeong KANG
Soenghun KIM

Assignees

SAMSUNG ELECTRONICS CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20230928
Priority Date: 20190214

Claims (6)

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).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of application Ser. No. 16/789,631, filed Feb. 13, 2020, now U.S. Pat. No. 11,778,679, which is based on and claims priority under 35 U.S.C. 119 to Korean Patent Application Nos. 10-2019-0017444, 10-2019-0035854 & 10-2019-0174454 filed on Feb. 14, 2019, Mar. 28, 2019 & Dec. 24, 2019, respectively, in the Korean Intellectual Property Office, the disclosure of which is herein incorporated by reference in their entireties. BACKGROUND 1. Field This disclosure relates generally to a wireless communication system and, more particularly, to a device and method for transmitting state information in a wireless communication system. 2. Description of Related Art To meet the demand for wireless data traffic having increased since deployment of 4th generation (4G) communication systems, efforts have been made to develop an improved 5th generation (5G) or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘Beyond 4G Network’ or a ‘Post Long Term Evolution (LTE) System’. The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 28 GHz or 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G communication systems. In addition, in 5G communication systems, development for system network improvement is under way based on advanced small cells, cloud Radio Access Networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), reception-end interference cancellation and the like. In the 5G system, Hybrid frequency shift keying (FSK) and quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed. In the wireless communication system, a terminal may detect a specific state and may transmit a message for reporting state information. Such state information may include a wireless connection state or a quality state such as quality of service (QoS). The state information may be received by a base station or another terminal, and may be processed in order to improve the state. The above information is presented as background information only to assist with an understanding of the disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the disclosure. SUMMARY Based on the above discussion, this disclosure provides an apparatus and method for transmitting state information in a wireless communication system. In addition, this disclosure provides an apparatus and method for transmitting a report of a master cell group (MCG) radio link failure (RLF) when the MCG RLF occurs in a wireless communication system. In addition, this disclosure provides an apparatus and method for satisfying a quality of service (QoS) requirement in vehicle-to-everything (V2X) communication in a wireless communication system. 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 comprises: 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. According to various embodiments of the present disclosure, 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 UE comprises: a transceiver; and at least one processor operably coupled to the transceiver, and configured to: detect a radio link failure (RLF) of the MCG; when the RLF of the MCG is detected, determine whether a transmission to the SCG is suspended; and when the transmission to the SCG is determined to be suspended, initiate a connection re-establishment procedure. Before undertaking the DETAILED DESCRIPTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated th