Sharp Kabushiki Kaisha Corporation

Fg Innovation Company Limited

Panasonic Intellectual Property Corporation of America

Takako Hori

Hidetoshi Suzuki

Joachim Loehr

Shohei Yamada

Prateek Basu Mallick

Ayako Horiuchi

Hidekazu Tsuboi

Kazunari Yokomakura

Hiroki Takahashi

Rikin Shah

Fangying Xiao

Ningjuan Chang

The present disclosure provides a method for link failure recovery during a handover and corresponding user equipment. The method performed in the user equipment (UE) comprises: after a successful handover procedure of the UE configured with a dual active protocol stack, if a radio link failure (RLF) of a master cell group occurs at the UE, then in a radio resource control re-establishment procedure for connection recovery, or when an RLF occurs on a source link, performing, by the UE, an operation of falling back from the dual active protocol stack to a single active protocol stack, releasing a protocol stack and a configuration associated with a source base station; when the link quality of the source base station is good, releasing, by the UE, a protocol stack and a configuration associated with a target base station, resuming a single connectivity state to the source base station, and reporting the failure information to the base station.

Radio link failure recovery method and corresponding user equipment

Provided is a terminal apparatus including a receiver configured to receive an RRC message including configuration information of an MBS from a base station apparatus, and a processing unit. The configuration information of the MBS includes MBS session information. The MBS session information includes PDU session information. The processing unit, based on initiation of reception of the MBS session by the terminal apparatus, establishes a radio bearer for the MBS, and performs processing of notifying a higher layer of a part or all of the MBS session information.

Terminal apparatus, method, and integrated circuit

A terminal apparatus for communicating with a base station apparatus is provided. The terminal apparatus includes a receiver configured to receive a Radio Resource Control (RRC) reconfiguration message including a parameter related to a first configuration from the base station apparatus, and a processing unit configured to perform configuration in accordance with the RRC reconfiguration message received. In a case that a first timer of an RRC protocol expires, a radio link failure of a source primary cell is not detected, and configuration related to Dual Active Protocol Stack (DAPS) handover is performed for the terminal apparatus, the processing unit reconfigures all of state variables configured for a Radio Link Control (RLC) entity of a Signaling Radio Bearer (SRB) in the source primary cell to respective initial values, resumes the SRB suspended in the source primary cell, and transmits an RRC message for notifying the base station apparatus that the DAPS handover has failed.

Terminal apparatus, base station apparatus, and method to perform configuration according to radio resource control reconfiguration message

A terminal apparatus for communicating with a base station apparatus is provided. The terminal apparatus includes a receiver configured to receive, from the base station apparatus, a Radio Resource Control (RRC) reconfiguration message including a parameter related to first configuration, and a processing unit configured to perform configuration in accordance with the RRC reconfiguration message received. In a case that a first timer of an RRC protocol expires, a radio link failure of a source primary cell is not detected, and configuration related to Dual Active Protocol Stack (DAPS) handover is performed for the terminal apparatus, the processing unit stops all of timers configured for a Radio Link Control (RLC) entity of a Signaling Radio Bearer (SRB) in the source primary cell, resumes the SRB suspended in the source primary cell, and transmits an RRC message for notifying the base station apparatus that the DAPS handover has failed.

Terminal apparatus, base station apparatus, and method

A terminal apparatus for communicating with a base station apparatus includes a receiver configured to receive, from the base station apparatus, an RRC reconfiguration message including a first configuration related to a radio bearer to which a Dual Active Protocol Stack (DAPS) is applied, and a processing unit configured to perform configuration in accordance with the RRC reconfiguration message. In a case that a first timer expires, that no radio link failure is detected in a source primary cell, and that the first configuration is performed on any radio bearer, the processing units releases a configuration for a target primary cell, resets MAC for the target primary cell, discards all data of a PDCP entity for a SRB of the source primary cell, discards all data of an RLC entity for the SRB of the source primary cell, resumes the SRB suspended in the source primary cell, and transmits, to the base station apparatus, an RRC message for notifying that a DAPS handover is unsuccessful.

A base station apparatus for communicating with a terminal apparatus transmits a Radio Resource Control (RRC) connection reconfiguration request message including a Data Radio Bearer (DRB) configuration to the terminal apparatus. The DRB configuration includes a DRB identity and a Packet Data Convergence Protocol Layer (PDCP) entity configuration corresponding to the DRB identity. PDCP entity configuration information includes one of a PDCP entity configuration for Evolved Universal Terrestrial Radio Access (E-UTRA) and a PDCP entity configuration for New Radio (NR). A PDCP entity is established in accordance with the PDCP entity configuration information.

User equipment and a master E-UTRAN node B

A terminal apparatus that communicates with one or multiple base station apparatuses includes: a receiver configured to receive an RRC connection reconfiguration message including a DRB configuration from a base station apparatus of the one or multiple base station apparatuses; and a processing unit configured to associate an DRB that is established with an EPS bearer identity included in information of a DRB configuration in a case that information indicating that a full configuration is applied is included in the RRC connection reconfiguration message received by the receiver, a DRB identity included in the information of the DRB configuration is not present in a part of a current configuration of the terminal apparatus, and an LTE PDCP entity is established in the DRB that is established and has the DRB identity.

Radio bearer establishment in wireless communication networks

A terminal apparatus includes a receiver configured to receive, from the base station apparatus, an RRC reconfiguration message including a DRB configuration, and a processing unit, wherein the processing unit performs, based on inclusion of a first parameter in the DRB configuration, configuration of a PDCP entity of a DRB corresponding to the DRB configuration, the configuration being related to a DAPS handover.

A terminal apparatus includes: a reception unit configured to receive an RRC reconfiguration message including a DRB configuration and a processing unit, wherein the processing unit establishes an SDAP entity based on conditions that a DRB identity included in the DRB configuration is not part of a configuration of the terminal apparatus, an SDAP configuration is included in the DRB configuration, and an SDAP entity corresponding to a PDU session information element included in the SDAP configuration does not exist, and indicates establishment of a user-plane resource for a PDU session to an upper layer based on an additional condition that the SDAP entity corresponding to the PDU session information element does not exist before the RRC reconfiguration message is received.

A terminal apparatus for communicating with a base station apparatus includes a receiver configured to receive, from the base station apparatus, a message indicating mobility from a first Radio Access Technology (RAT) to a second RAT, and a processing unit configured to attempt to select a cell. A requirement for the processing unit to attempt to select a cell in the second RAT in a case that processing of the mobility in accordance with the message fails is that establishment of a connection to the second RAT is not successful and first information is included in the message.

Terminal apparatus and communication method

Provided is a terminal apparatus, wherein based on detection of a request, for a PDCP SDU received from an upper layer, the terminal apparatus performs header compression of the PDCP SDU by using second header compression processing, performing ciphering by using a second ciphering algorithm, a second ciphering key, and a COUNT value, performs integrity protection of the PDCP SDU by using a second integrity protection algorithm, a second integrity protection key, and the COUNT value, and submits a PDCP PDU created, to the second RLC entity.

Efficient control of mobility for communications between terminal apparatus and base station apparatus

A terminal apparatus applies a configuration of an RRC reconfiguration message to a second configuration which is identical to a part or entirety of a first configuration in a case that the RRC reconfiguration message includes first information, and applies the configuration of the RRC reconfiguration message to the first configuration in a case that the RRC reconfiguration message includes no first information.

A terminal apparatus includes: a receiver that receives an RRC message from a base station apparatus; and a processing unit that performs processing of RRC. The processing unit causes, when first information is in the RRC message, a first timer to start in a running state, and considers, at least when a random access problem indication is received from a MAC entity of the group and the first timer is not running, or when a random access problem indication is received from a MAC entity of the group and the first timer is running under a specific condition, a radio link failure for the group to be detected. When the radio link failure for the group is detected and that the first timer is running under the specific condition, the processing unit suspends transmission of all radio bearers in the group, and resets the MAC entity of the group.

The present disclosure provides a technology pertaining to a terminal device, a base station device, a method and an integrated circuit which can reduce the complexity of protocol processing and perform efficient communications. The terminal device includes: a receiving unit which receives an RRC connection reconfiguration message from the base station device; and a processing unit, wherein, when information for indicating that full configuration is applied is included in the RRC connection reconfiguration message, on the basis of the terminal device performing an E-UTRA/5GC or NGEN-DC, performs an RLC entity re-establishment, an NR PDCP entity release, an RLC entity release, a logical channel release, and a DRB identifier on a DRB which corresponds to each DRB identifier set by the terminal device release, and performs an SDAP entity notification, which corresponds to the DRB, of a release of the DRB.

Terminal device, base station device, and method

A terminal apparatus is provided. The terminal apparatus includes a receiver configured to receive a first message from a base station apparatus, and a processing unit configured to modify first data radio bearer configuration configured for the terminal apparatus, based on the first message. A first PDCP entity is reconfigured as a packet data convergence protocol (PDCP) entity for the first data radio bearer. A first secrecy key for a source and a second secrecy key for a target are configured for the first PDCP entity as secrecy keys for the first data radio bearer. In a case that the first message includes first information and second information, the second secrecy key for the target of the first PDCP entity is configured based on the second information. In a case that the first message does not include the first information, the first secrecy key for the source is applied to the second secrecy key for the target of the first PDCP entity.

Growing community of inventors

Sakai, Japan

Takako Hori