Patent Application
20240259865
The present disclosure relates to a radio communication device.
Currently, radio communication networks using mobile terminals (smartphones and feature phones) are expanding. With the expansion of radio communications, higher speeds and larger capacities are sought.
Technologies that achieve higher speed and larger capacity include Dual Connectivity (DC). DC is a technology in which a terminal device wirelessly connects to a master base station device and a secondary base station device, and performs radio communication using the carriers of the base station devices (hereinafter may be referred to as cell groups).
Furthermore, as the generations of radio communication standard progress, attention has been directed toward Multi Radio Dual Connectivity (MR-DC), which is a DC technology that uses eNodeB (hereinafter may be referred to as eNB), which is a base station device associated with Four-Generation (4G) and Five-Generation (5G), and gNodeB (hereinafter may be referred to as gNB), which is a base station device associated with 5G-Advanced and New Radio (NR).
When the amount of data to be transmitted and received in MR-DC is large, the terminal device transmits and receives data to and from both the master base station device and the secondary base station device, for example. On the other hand, when the amount of data to be transmitted and received in MR-DC is small, measures have been contemplated to save power by suspending data communication between the terminal device and the secondary base station device by deactivating the cell group (secondary cell group) belonging to the secondary base station device.
Technologies relating to MR-DC are described in the following related art literature.
A base station device includes, a transmitter configured to transmit a Radio Resource Control (RRC) message including information for configuring a secondary cell group to a terminal device, and a controller configured to control to refrain from performing first processing on the terminal device when the secondary cell group that is configured for the terminal device through the RRC message is in a first state.
The object and advantages of the disclosure will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the disclosure.
The trigger and timing for a terminal device to shift the secondary cell group from a suspended state (inactive state) to an active state have not been determined as standard specifications.
For example, if a terminal device activates the secondary cell group at an unnecessary timing, unnecessary power would be consumed.
Referring to the drawings, the present embodiment is described in detail below. The issues and examples in this specification are merely examples, and do not limit the scope of right in this application. In particular, the technologies of the present application are applicable to different expressions that are technically equivalent, and the scope of rights is not limited.
The terminal device 100 is wirelessly connected to the base station devices 200-1 and 200-2 and performs radio communication using MR-DC. The terminal device 100 may be a tablet terminal or a smartphone that supports multiple generations (for example, 4G and 5G, Evolved Universal Terrestrial Radio Access (E-UTRA), which is a 4G radio access technology, and NR, which is a 5G radio access technology).
The base station devices 200-1 and 200-2 (hereinafter may be referred to as base station devices 200) are communication devices that are wirelessly connected to the terminal device 100 and perform radio communication using MR-DC. The base station devices 200-1 and 200-2 may be connected to each other by wire and communicate with each other, for example. The base station devices 200 may be connected to the core network 300 and communicate with the core network 300, for example. The base station device 200 may be a base station device of eNodeB or gNodeB, for example.
The core network 300 is a network that supports a certain generation. The core network 300 may be a core network supporting 5G (hereinafter may be referred to as 5GC) or an Evolved Packet Core (EPC) supporting 4G.
Details of MR-DC implemented in the communication system 10 will be described below.
The storage 220 is an auxiliary storage device, such as a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD), that stores programs and data. The storage 220 stores therein a radio communication program 221, an MR-DC master node program 222, and an MR-DC secondary node program 223.
The memory 230 is an area into which the programs stored in the storage 220 are loaded. The memory 230 may also be used as an area for programs to store data.
The radio communication circuit 240 is a circuit that wirelessly connects to the terminal device 100 and communicates with the terminal device 100. For example, the base station device 200 receives signals transmitted from the terminal device 100 and transmits signals to the terminal device 100 via the radio communication circuit 240.
A network interface (NI) 250 may be a communication device that connects to another base station device 200 and performs inter-base station communication, for example. Also, the NI 250 may be a communication device that connects to the core network 300 (a communication device that forms the core network 300) and communicates with the core network 300, for example. The NI 250 may be a Network Interface Card (NIC), for example. The base station device 200 receives signals from other communication devices and transmits signals to other communication devices via the NI 250.
The CPU 210 is a processor that loads a program stored in the storage 220 into the memory 230, executes the loaded program, constructs each unit, and implements each processing.
The CPU 210 performs radio communication processing by executing the radio communication program 221. The radio communication processing may be processing involving radio connection with the terminal device 100, radio communication with the terminal device 100, and relaying the communication between the terminal device 100 and other communication devices.
By executing the MR-DC master node program 222, the CPU 210 constructs a second transmission unit, a second reception unit, and a second processing unit, and performs MR-DC master node processing. The MR-DC master node processing is processing for controlling the master node side in MR-DC. In MR-DC master node processing, the base station device 200 performs communication corresponding to each type of MR-DC, which will be described below.
The CPU 210 executes MR-DC secondary node program 223 to construct a second transmission unit, a second reception unit, and a second processing unit, and performs MR-DC secondary node processing. The MR-DC secondary node processing is processing for controlling the secondary node side of MR-DC. In MR-DC secondary node processing, the base station device 200 performs communication corresponding to each type of MR-DC, which will be described below.
The storage 120 is an auxiliary storage device, such as a flash memory, HDD, or SSD, that stores therein programs and data. The storage 120 stores therein a terminal-side radio communication program 121 and a terminal-side MR-DC program 122.
The memory 130 is an area into which programs stored in the storage 120 are loaded. The memory 130 may also be used as an area for programs to store data.
The communication circuit 140 is a circuit that connects to and communicate with the base station device 200. The communication circuit 140 may be a network card that supports radio connection, for example.
The CPU 110 is a processor that loads a program stored in the storage 120 into the memory 130, executes the loaded program, constructs each unit, and implements each processing.
The CPU 110 performs terminal-side radio communication processing by executing the terminal-side radio communication program 121. The terminal-side radio communication processing is processing involving radio connection with the base station device 200, radio communication with the base station device 200, and relaying the communication between the base station device 200 and other communication devices.
The CPU 110 executes the terminal-side MR-DC program 122 to construct a transmission unit, a reception unit, and a processing unit, and performs terminal-side MR-DC processing. The terminal side MR-DC processing is processing for controlling communication in MR-DC. In the terminal side MR-DC processing, the terminal device 100 performs communication corresponding to each type of MR-DC, which will be described below.
Examples of protocol stacks of the communication system 10 are now described. A representation in a hierarchical structure of a series of protocols for transmitting and receiving data in the communication system 10 is referred to as a protocol stack. In the following example, a situation is described where the base station device 200 is gNB and the core network 300 is 5GC. Also, the terminal device 100 (UE: User Equipment) supports the gNB and the 5G core.
The protocol stacks of Control Plane (C-Plane) and User Plane (U-Plane) are described below. C-Plane may represent control signals (messages) transmitted and received in communication, for example. U-Plane may represent data signals (messages) of user data that are transmitted and received, for example.
In
PHY uses physical channels to transmit control information and data between the terminal device 100 and the base station device 200. The direction from the base station device 200 to the terminal device may be referred to as downlink (down, DL), and the direction from the terminal device 100 to the base station device may be referred to as uplink (up, UL).
The MAC performs mapping between logical channels (LCH) and transport channels, multiplexing/demultiplexing of MAC SDUs, scheduling reports, error correction through Hybrid Automatic Repeat reQuest (HARQ), priority control, and the like.
A Service Data Unit (SDU) refers to data that is passed from or to upper layers in each sublayer. A Protocol Data Unit (PDU) refers to data passed from or to lower sublayers in each sublayer.
In RLC, PDCP, and SDAP, there are PDUs for control, which may be referred to as control PDUs. The other PDUs may be referred to as data PDUs to distinguish them from control PDUs.
RLC has three modes of Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). RLC may perform transfer of upper layer PDUS, assignment of sequence numbers (in UM and AM), division (in UM and AM) and re-division (in AM) of data, reassembling of SDUs (in UM and AM), duplicate detection (in AM), RLC SDU discard (in UM and AM), and RLC re-establishment, for example.
PDCP may perform U-Plane and C-Plane data transfer, PDCP sequence number management, header compression, encryption/decryption, integrity protection/integrity verification, timer-based SDU discard, routing for split bearers, reordering, and in-order delivery, for example.
SDAP may perform mapping between Quality of service (QOS) flows and Data Radio Bearers (DRBs) and marking of QoS flow identifier (QFI) in downlink (DL) packets and uplink (UL) packets, for example.
Upper layers of U-Plane may include Internet Protocol (IP), Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and application layers, for example.
In
RRC may perform broadcasting of system information (SI) relating to Access Stratum (AS) and NAS, paging, establishment/maintenance/release of RRC connection between the terminal device 100 and the base station device 200, addition/modification/release of carrier aggregation (CA), addition/modification/release of dual connectivity (DC), security function including security key management, establishment/configuration/maintenance/release of Signaling Radio Bearer (SRB) and data radio bearer (DRB), mobility function, QoS management function, terminal device measurement report and reporting control, radio link failure (RLF) detection and recovery, NAS message transfer, and the like.
The NAS may perform authentication, mobility management, and security control, for example.
When the device of the core network 300 is EPC (Evolved Packet Core), there is no SDAP in the U-Plane. The C-Plane NAS terminates between the terminal device 100 and Mobility Management Entity (MME), which is a device of the core network 300 and forms the EPC.
The channels used in the communication system 10 are now described. Examples of channels corresponding to NR are described below, but the channels used are not limited to the following. Also, channels with the same name may be used in generations other than NR.
Physical Broadcast CHannel (PBCH) is a channel used to transmit broadcast information from the base station device 200 to the terminal device 100.
Physical Downlink Control CHannel (PDCCH) is a channel used to transmit Downlink Control Information (DCI) from the base station device 200 to the terminal device 100, for example.
Physical Downlink Shared CHannel (PDSCH) is a channel used to transmit data from upper layers from the base station device 200 to the terminal device 100, for example.
Physical Uplink Control CHannel (PUCCH) is a channel used to transmit Uplink Control Information (UCI) from the terminal device 100 to the base station device 200, for example.
Physical Uplink Shared CHannel (PUSCH) is a channel used to transmit data from upper layers from the terminal device 100 to the base station device 200, for example.
Physical Random Access CHannel (PRACH) is a channel used to transmit a random access preamble from the terminal device 100 to the base station device 200, for example.
Broadcast Channel (BCH) is mapped to PBCH, which is a physical channel.
Downlink Shared Channel (DL-SCH) is mapped to PDSCH, which is a physical channel.
Paging Channel (PCH) is mapped to PDSCH, which is a physical channel.
Downlink Shared Channel (UL-SCH) is mapped to PUSCH, which is a physical channel.
Random Access Channel(s) (RACH) is mapped to PRACH, which is a physical channel.
Broadcast Control Channel (BCCH) is a downlink channel for broadcasting system information and is mapped to the BCH transport channel.
Paging Control Channel (PCCH) is a downlink channel for carrying paging messages, and is mapped to the PCH transport channel.
Common Control Channel (CCCH) is a channel for transmitting control information (such as RRC messages) between the terminal device 100 and the base station device 200, and a channel used for the terminal device 100 that does not maintain (has) RRC connection with the base station device 200. CCCH is mapped to the DL-SCH transport channel for downlink, and is mapped to the UL-SCH transport channel for uplink.
Dedicated Control Channel (DCCH) is a point-to-point bidirectional channel that transmits dedicated control information (such as RRC messages) between the terminal device 100 and the base station device 200, is used for the terminal device 100 that has RRC connection with the base station device 200. DCCH is mapped to the DL-SCH transport channel for downlink, and is mapped to the UL-SCH transport channel for uplink.
Dedicated Transport Channel (DTCH) is a bidirectional channel dedicated to point-to-point terminals and transmits user information (user data). DTCH is mapped to the DL-SCH transport channel for downlink, and is mapped to the UL-SCH transport channel for uplink.
The RRC message is now described. An RRC message is a message that includes information needed for communication in the cell, and includes a Master Information Block (MIB), a system information block, and the like. Parameters included in an RRC message may be referred to as fields or Information Elements (IEs).
RRC messages also include a message regarding RRC connection establishment. Examples of messages regarding RRC connection establishment include an RRC setup request message (RRCSetupRequest), an RRC setup message (RRCSetup), and an RRC setup completion message (RRCSetupComplete).
RRC messages also include a message regarding Access Stratum (AS) security initial activation. Examples of messages regarding AS security initial activation include a security mode command message (SecurityModeCommand).
RRC messages also include messages regarding RRC connection reconfiguration. Examples of the messages regarding RRC connection reconfiguration include an RRC reconfiguration message (RRCReconfiguration) and an RRC reconfiguration complete message (RRCReconfigurationComplete).
RRC Reconfiguration includes, as parameters, radioBearerConfig, radioBearerConfig2, masterCellGroup, secondaryCellGroup, masterKeyUpdate, and sk-counter.
radioBearerConfig and radioBearerConfig2 are configurations relating to MN-terminated bearers or SN-terminated bearers, and may include SRB configuration, DRB configuration, security configuration, and the like. The SRB configuration (DRB configuration) may include an SRB identifier (DRB identifier), parameters instructing PDCP configuration and PDCP re-establishment, and the like. The security configuration includes the parameter indicating whether to use a master key or a secondary key (keyToUse).
masterCellGroup and secondaryCellGroup are MCG configuration and SCG configuration, respectively, and may include a cell group identifier, RLC bearer configuration, SpCell configuration, and the like. The RLC bearer configuration may include a logical channel identifier, RLC configuration, a radio bearer identifier (SRB identifier or DRB identifier) associated with the RLC bearer, and the like. The SpCell configuration may include information needed for reconfiguration with sync.
masterKeyUpdate includes information needed to update the master key.
sk-counter includes information needed for secondary key generation.
Format E11 is a diagram illustrating examples of parameters of RadioBearerConfig included in RRCReconfiguration.
Format E12 is a diagram illustrating examples of parameters of CellGroupConfig included in RRCReconfiguration.
Format E111 is a diagram illustrating examples of SRB-ToAddMod parameters included in RadioBearerConfig.
Format E112 is a diagram illustrating examples of DRB-ToAddMod parameters included in RadioBearerConfig.
Format E113 is a diagram illustrating examples of SecurityConig parameters included in RadioBearerConfig.
Format E121 is a diagram illustrating examples of parameters of RLC-BearerConfig included in CellGroupConfig.
Format E122 is a diagram illustrating examples of parameters of SpCellConfig included in CellGroupConfig.
RRC messages may further include messages regarding re-establishment of RRC connection, messages regarding release and suspension of RRC connection, messages regarding resumption of RRC connection, messages regarding terminal device capabilities, messages regarding terminal information, and messages regarding radio link failure of MCG and SCG.
Message regarding RRC connection reconfiguration may perform establishment, configuration, modification, release, and reconfiguration with sync of radio bearers, cell groups, measurement information, for example.
Examples of radio bearers of the communication system 10 are now described.
Signaling Radio Bearer (SRB) is a radio bearer for transmitting RRC messages and NAS messages.
SRB0 is a radio bearer for RRC messages that use the Common Control CHannel (CCCH) logical channel.
SRB1 is a radio bearer for RRC messages and NAS messages that use the Dedicated Control CHannel (DCCH) logical channel before SRB2, which is described below, is established.
SRB2 is a radio bearer for NAS messages and RRC messages that include logged measurement information, and uses the Dedicated Control CHannel (DCCH) logical channel. The priority of SRB2 is lower than SRB1, and may be configured by the base station device 200 after AS security is activated.
SRB3 is a radio bearer for RRC messages used when EN-DC, NGEN-DC, or NR-DC is configured in the terminal device 100, and uses the Dedicated Control CHannel (DCCH) logical channel. EN-DC, NGEN-DC, and NR-DC are types of MR-DC, and details of the types of MR-DC will be described below.
Data Radio Bearer (DRB) is a radio bearer for transmitting user data.
SRB1 and SRB2 include one PDCP and one or more RLC bearers. An RLC bearer includes RLC and MAC logical channels. It is assumed that MAC exists for each cell group described below. The mode of RCL is AM.
SRB3 includes one PDCP and one RLC bearer. The RLC mode is AM.
A DRB includes one PDCP and one or more RLC bearers. The RLC mode is UM or AM. A DRB may be referred to as UM DRB when RLC is UM, and as AM DRB when RLC is AM. A DRB is associated with one SDAP when the core network 300 is 5GC (core supporting 5G), and is associated with one EPS bearer (or EPS bearer identity) when the core network 300 is EPC.
5GC is a core network standardized for 5G and is described in 3GPP standards such as TS 23.501 and TS 23.502, for example.
EPC is a core network standardized for 4G and is described in 3GPP standards such as TS 23.401 and TS 23.402, for example.
Cell Group (CG) represents the configuration of cells in MR-DC. In MR-DC, cell groups are classified as a Master Cell Group (MCG) or Secondary Cell Group (SCG).
CG includes one Special Cell (SpCell), or includes one SpCell and one or more secondary cells (SCell).
SpCell in MCG may be referred to as a primary cell (PCell). Also, SpCell in SCG may be referred to as a primary SCG cell (PSCell).
In
The MCG may be a CG when MR-DC is not configured, or a CG belonging to the master node when MR-DC is configured.
The SCG is a CG belonging to the secondary node in MR-DC.
The PCell is a cell that operates on the primary frequency in the MCG and is used by the terminal device 100 for initial connection establishment procedures, connection re-establishment procedures, and the like. Connection establishment/re-establishment procedures include a random access procedure.
The PSCell is a cell used in the SCG for a random access procedure when the terminal device 100 performs reconfiguration with sync.
The SCell is a cell that provides additional radio resources in addition to the SpCell to the terminal device 100 for which carrier aggregation is configured.
The types of MR-DC are now described. MR-DC is classified into four types depending on the type (supporting generation) of the base station devices 200 of the master node and the secondary node and the type (supporting generation) of the core network 300.
EN-DC and NGEN-DC may also be referred to as (NG)EN-DC. The secondary node of EN-DC may be referred to as en-gNB. The master node of NGEN-DC may be referred to as ng-eNB.
Bearer types in MR-DC are now described. Hereinafter, a configuration in which PDCP terminates at the master node and the master node side has PDCP may be referred to as MN-terminated. A configuration in which PDCP terminates at the secondary node and the secondary node side has PDCP may be referred to as SN-terminated. Bearer types are classified into the following six types.
A DRB has one of the six bearer types described above.
SRB1 and SRB2 may be MN-terminated MCG bearers or MN-terminated Split bearers. When SRB1 and SRB2 are MN-terminated Split bearers, they may be referred to as splitSRB1 and splitSRB2, respectively.
SRB3 is an SN-terminated SCG bearer.
Also, Primary Path is configured for a Split bearer. Primary Path indicates the base station device 200 to which the terminal device 100 transmits data (preferentially) in the initial state. Primary Path is specified by the cell group (MCG, SCG) and LCH. The terminal device 100 transmits data to the base station device 200 of Primary Path unless the amount of uplink transmission data exceeds a threshold. The terminal device 100 may transmit data to either base station device 200 when the threshold is exceeded.
The security key used in PDCP for MN-Terminated (master key) differs from that used for SN-Terminated (secondary key).
Reconfiguration with sync (handover) is now described. Reconfiguration with sync represents a procedure performed by the terminal device 100 when the base station device 200 causes an RRC reconfiguration message (RRCReconfiguration) that is to be transmitted to the terminal device 100 to include a parameter indicating that reconfiguration with sync is to be performed (reconfigurationWithSync: hereinafter may be referred to as reconfiguration with sync parameter).
Reconfiguration with sync is a procedure in which the terminal device 100 changes the PCell and PSCell, and includes operations such as random access to the new (changed, target) PCell and PSCell, MAC reset, RLC re-establishment, and PDCP data recovery (for AM DRB).
Additionally, reconfiguration with sync may involve a change of the security key. In this case, PDCP re-establishment is performed in addition to the above.
When the security key is changed, a new key is generated at the RRC of the terminal device 100 and the PDCP is re-established, so that the new key is applied to the PDCP.
In the terminal device 100, when a DRB to which a certain QoS flow is associated (mapped) is changed, an end marker control PDU is transmitted to the DRB before change.
A QoS flow is a Service Data Flow (SDF) with the same QoS requirement and is identified by a QoS flow identifier (QFI). SDFs may be an IP flow, an Ethernet flow, and the like, and vary depending on the upper layers.
The RRC state of the terminal device 100 indicates the state regarding the RRC connection of the terminal device 100. A state in which RRC connection with the base station device 200 is not established may be referred to as RRC idle mode (RRC_IDLE). A state in which RRC connection with the base station device 200 is established may be referred to as RRC connection mode (RRC_CONNECTED). A state in which RRC connection with the base station device 200 is suspended may be referred to as RRC inactive mode (RRC_INACTIVE).
In (NG)EN-DC or NR-DC, the SCG configured for the terminal device 100 may be deactivated (SCG deactivation) to limit communication between the secondary node and the terminal device 100. A situation where the SCG is in an inactive state may be referred to as in SCG deactivation. A situation where the SCG is in an active state may be referred to as in SCG (re)activation. Turning the SCG into an inactive state may be referred to as SCG deactivation. Turning the SCG in an inactive state into an active state may be referred to as SCG (re)activation.
Also, hereinafter, “reactivation” and “reactivate” include “activation” and “activate”, respectively.
It is assumed that the terminal device 100 in SCG deactivation satisfies a condition including some or all of the following conditions.
A first embodiment is now described. In communication between the terminal device 100 and the secondary node (base station device 200), the communication system 10 appropriately controls the switching from in SCG deactivation to in SCG (re)activation, or from in SCG (re)activation to in SCG deactivation. Appropriate control may include controlling to avoid unnecessary switching or postponing the switching timing to a needed timing to save power.
In the sequence of
The terminal device 100 transmits a terminal information notification to the base station device 200 (S102). The terminal information notification may be an RRC message or a parameter included in an RRC message, for example. Also, the terminal information notification may be UE assistance information of an RRC message, or may be a message with another name.
For example, the terminal information notification may include information indicating whether the terminal device 100 needs to save power. The terminal device 100 determines whether power saving is needed on the basis of the remaining battery level.
Also, the terminal information notification may include information indicating whether SCG deactivation (or SCG release) is needed. For example, the terminal device 100 may determine the necessity on the basis of the amount of communication (data communication amount) with the secondary node.
The terminal information notification may include information indicating whether to, when the SCG reconfiguration with sync parameter is received in SCG deactivation (an instruction to perform SCG reconfiguration with sync is given), perform (want to perform) it immediately.
Furthermore, the terminal information notification may include information indicating to perform (want to perform) SCG reactivation when UL data is generated, without permission of the base station device 200 (without transmitting an SCG reactivation request of processing S110, which will be described below). This allows for the omission of some of the messages between the base station device 200 and the terminal device 100 in SCG reactivation.
Upon receiving a terminal information notification (S102), the base station device 200 performs SCG deactivation determination processing (S103). In addition to when a terminal information notification is received, the base station device 200 may perform SCG deactivation determination processing S103 when an event that involves (or potentially involves) SCG deactivation occurs.
The SCG deactivation determination processing S103 is processing for determining whether to perform SCG deactivation on the terminal device 100. In the SCG deactivation determination processing S103, the base station device 200 performs determination according to the amount of communication between the terminal device 100 and the secondary node. When the amount of communication with the secondary node is low, such as when the amount of communication with the secondary node is less than or equal to a predetermined value in a predetermined period, or when there is no communication with the secondary node for a predetermined time, the base station device 200 determines to perform SCG deactivation.
Furthermore, in the SCG deactivation determination processing S103, the base station device 200 performs determination according to the amount of radio resources that can be allocated to the secondary node. For example, the base station device 200 determines to perform SCG deactivation when the amount of available radio resources of the secondary node is less than or equal to a predetermined value.
When determining to perform SCG deactivation in the SCG deactivation determination processing S103, the base station device 200 transmits an SCG deactivation instruction to the terminal device 100 (S104). The SCG deactivation instruction is a message instructing the terminal device 100 to perform SCG deactivation. The SCG deactivation instruction may be an RRC message or a parameter included in an RRC message. Furthermore, the SCG deactivation instruction may be SCG deactivation or RRCReconfiguration of an RRC message, or may be a message with another name.
For example, the SCG deactivation instruction may include information indicating whether to, when an instruction to perform SCG reconfiguration with sync is given while the terminal device 100 is in SCG deactivation, immediately perform all or part of the processing of SCG reconfiguration with sync. When the information indicates to immediately perform all, the terminal device 100 immediately performs SCG reconfiguration with sync. When the information indicates not to immediately perform part or all, the terminal device 100 performs, at subsequent SCG reactivation, the part of the processing of SCG reconfiguration with sync that is not performed (suspends reconfiguration with sync), or does not perform part or all of the processing of SCG reconfiguration with sync (discards some or all of the instructions (parameters) for reconfiguration with sync).
Furthermore, the SCG deactivation instruction may include information instructing to immediately perform part or all of the processing of SCG reconfiguration with sync if at least a first condition is not satisfied when the terminal device 100 in SCG deactivation is instructed to perform SCG reconfiguration with sync. In this case, if at least the first condition is not met, the terminal device 100 immediately performs SCG reconfiguration with sync. In this case, if at least the first condition is satisfied, the terminal device 100 performs part of all of the processing of SCG reconfiguration with sync when SCG reactivation is subsequently performed (suspends part or all of the processing of SCG reconfiguration with sync), or does not perform part or all of the processing of SCG reconfiguration with sync (discards part of all of the instruction (parameter) of reconfiguration with sync.
The first condition may be that conditions including some or all of the following Condition 1 to Condition 4 are satisfied.
When at least the first condition is satisfied, the communication in MR-DC (particularly the communication using the master node) is not obstructed even if the terminal device 100 does not immediately perform part or all of the processing of SCG reconfiguration with sync. In this manner, the terminal device 100 does not perform unnecessary SCG reactivation, thereby reducing power consumption.
The SCG deactivation instruction may include information instructing to immediately perform SCG reconfiguration with sync when the terminal device 100 in SCG deactivation is instructed to perform SCG reconfiguration with sync. In this case, the terminal device 100 immediately performs SCG reconfiguration with sync regardless of the first condition.
Also, the SCG deactivation instruction may include information instructing to perform SCG reactivation without permission of the base station device 200 when UL data is generated. In this case, the terminal device 100 immediately performs SCG reactivation.
Upon receiving an SCG deactivation instruction (S104), the terminal device 100 performs SCG deactivation processing (S105). The SCG deactivation processing S105 is processing for transition to SCG deactivation. The terminal device 100 may determine that SCG deactivation processing S105 needs to be performed when an SCG deactivation instruction is received, and perform SCG deactivation processing (S105). Also, the terminal device 100 may determine that SCG deactivation processing S105 does not need to be performed when an SCG deactivation instruction is not received, and refrain from performing SCG deactivation processing (S105).
In SCG deactivation processing S105, the terminal device 100 stops some or all of the timers running in relation to the SCG. The terminal device 100 also resets some or all of the counters set in the SCG. The terminal device 100 also resets the MAC of the SCG. The terminal device 100 also performs second processing on all or some of the radio bearers that satisfy at least a second condition. The second condition may be being an SCG bearer or being a split bearer with a Primary Path set to the SCG.
The timer running in relation to the SCG to be stopped may include a timer for detecting a radio link failure of the SCG. Also, the timer running in relation to the SCG to be stopped may include a timer for the measurement report of the SCG.
The counters set in the SCG to be reset may include a counter for detecting a radio link failure of the SCG.
Additionally, “performs second processing on all or some of the radio bearers that satisfy at least a second condition” may include a situation where the terminal device 100 determines whether each radio bearer satisfies at least the second condition, and if it is determined that at least the second condition is satisfied, the second processing is performed on this radio bearer.
Furthermore, “performs second processing on all or some of the radio bearers that satisfy at least a second condition” may include a situation where the terminal device 100 determines whether each radio bearer satisfies at least the second condition, and if it is determined that at least the second condition is satisfied and that the second processing needs to be performed on this radio bearer, the second processing is performed on this radio bearer.
In the second condition, “being an SCG bearer” may refer to that one or both of a parameter indicating one or more RLC (moreThanOneRLC) and a parameter indicating Primary Path (primaryPath) are not set in the radio bearer (PDCP of the radio bearer), and the RLC bearer of the radio bearer is in the SCG. Also, “being an SCG bearer” in the second condition may refer to that the RLC bearer of the radio bearer exists only in the SCG. This “RLC bearer of the radio bearer” may be an RLC bearer associated with the radio bearer.
Furthermore, “being a split bearer with a Primary Path set to the SCG” in the second condition may refer to that the Primary Path (or a parameter indicating Primary Path) of the radio bearer (PDCP of the radio bearer) is set to the SCG (or that the SCG is referred to).
The second processing is processing that is performed for all or some of the radio bearers that satisfy at least the second condition. The second processing is all or part of the processing and pre-processing for transition to SCG deactivation. The second processing may include all or part of the following processing. Hereinafter, all or some of the radio bearers that satisfy at least the second condition may be referred to as second radio bearers.
In the processing of immediately transmitting data for which transmission has not completed in PDCP, for an UM DRB, for example, PDCP SDUs that have been assigned a sequence number but have not been passed to lower layers may be regarded as PDCP SDUs that are newly received from upper layers and transmitted in order. In this case, the discard timer does not need to be restarted.
In the processing of immediately transmitting data for which transmission has not completed in PDCP, for an AM DRB or an AM DRB in which the PDCP entity is not suspended, for example, PDCP SDUs for which successful transmission has not been confirmed from lower layers, and PDCP SDUs that have been assigned a sequence number but have not been passed to lower layers are transmitted in order.
In the processing of immediately transmitting data for which transmission has not completed in PDCP, for an AM DRB for the Uu interface (interface between the terminal device 100 and the base station device 200) in which the PDCP entity is suspended, for example, PDCP SDUs for which successful transmission has not been confirmed from lower layers, and PDCP SDUs that have been assigned a sequence number but have not been passed to lower layers may be regarded as PDCP SDUs that are newly received from upper layers and transmitted in order. In this case, the discard timer does not need to be restarted.
The discard timer may be a timer used to discard the corresponding PDCP SDU when it expires.
Examples of actions within the terminal in performing the second processing on all or some of the radio bearers that satisfy at least the second condition are now described.
For example, the RRC of the terminal device 100 issues a second notification to PDCP of all or some of the radio bearers that are SCG bearers or split bearers. PDCP may be replaced by lower layer(s). Upon receiving the second notification, PDCP performs the second processing if the radio bearer is an SCG bearer (with one associated RLC) or a split bearer (with two or more associated RLCs) with a Primary Path set to the SCG side.
For example, the RRC of the terminal device 100 issues a second notification to the second radio bearer. PDCP may be replaced by lower layers(s). Upon receiving the second notification, the PDCP performs the second processing.
Some of the radio bearers that satisfy at least the second condition may be SRBs that satisfy at least the second condition, or DRBs that satisfy at least the second condition. There is no limitation to the above.
The second notification may be a notification that includes information instructing to discard PDCP data. The second notification may also be a notification that includes information instructing to immediately transmit data for which transmission has not completed.
The second notification may also include information indicating that the SCG is deactivated, such as SCG deactivated and CG UL transmission prohibited (suspended).
The second notification may include all or part of the above information. The second notification may also be a plurality of messages including some of the above information.
As a result, even if the PDCP of the SCG is re-established when the terminal device 100, despite having received an instruction for SCG reconfiguration with sync, does not immediately perform it and performs it with delay, uplink transmission resulting from transmission of UL data that has not been successfully transmitted is unlikely to occur. This allows the terminal device 100 to limit unnecessary SCG reactivation and thus limit power consumption.
Furthermore, in SCG deactivation processing S105, the RRC of the terminal device 100 transmits second information to the SDAP that is associated with DRBs of the second radio bearers.
The second information is information indicating that UL transmission is not possible with the DRB, such as that UL transmission is prohibited (or stopped) with the DRB, or that the cell group associated with the DRB is in deactivation.
The second information may also be transmitted to SDAP along with all or part of the following information. Also, the second information may be all or part of the following information.
DRB identity of the DRB
Also, “transmits second information to the SDAP that is associated with DRBs of the second radio bearers” may refer to that the terminal device 100 determines whether each DRB satisfies at least the second condition, and if it is determined that the DRB satisfies at least the second condition and that the transmission of the second information to the SDAP associated with this DRB is needed, the terminal device 100 transmits the second information to the SDAP associated with this DRB.
The second information transmission processing may be performed if a DRB that satisfies at least the second condition is associated with SDAP (if SDAP entity associated with this DRB configured). The terminal device 100 may determine whether each DRB is associated with SDAP, and if it is determined that the DRB is associated with SDAP, determine whether this DRB satisfies at least the second condition. The terminal device 100 may also determine whether each DRB satisfies at least the second condition, and if it is determined that at least the second condition is satisfied, determine whether this DRB is associated with SDAP.
The base station device 200 transmits an RRC reconfiguration message (first message) to the terminal device 100 in SCG deactivation (S106). The RRC reconfiguration message is an RRC message that is transmitted from the base station device 200 to the terminal device 100 regarding RRC connection reconfiguration, and may perform establishment, configuration, modification, release, and reconfiguration with sync of radio bearers, cell groups, and measurement information, for example. The RRC reconfiguration message may be RRCReconfiguration of RRC message, or may be a message with another name.
When the base station device 200 determines that a change of the configuration of the terminal device 100 (change of the configuration in RRC connection mode) is needed, it generates an RRC reconfiguration message and transmits it to the terminal device 100.
For example, when an MCG handover is needed, the base station device 200 determines that the configuration of the terminal device 100 needs to be changed.
Also, when a security key needs to be changed, the base station device 200 determines that the configuration of the terminal device 100 needs to be changed. When the PDCP associated with the security key that needs to be changed (PDCP that uses a key that is derived from the security key) needs to be re-established, the base station device 200 determines that the configuration of the terminal device 100 needs to be changed.
Also, when the QoSflow to DRB mapping rule (a rule indicating the relationship (map) between QoS flow and DRB) needs to be changed, for example, the base station device 200 determines that the configuration of the terminal device 100 needs to be changed.
The RRC reconfiguration message may include the following information.
When the base station device 200 determines that it does not want the terminal device 100 to immediately perform SCG reconfiguration with sync, the RRC reconfiguration message does not need to include the reconfiguration with sync parameter in the parameters indicating SCG configuration (e.g., the name secondaryCellGroup) (SCG reconfiguration with sync does not have to be requested).
Furthermore, when the terminal device 100 is in SCG deactivation, the base station device 200 may determine that including the SCG reconfiguration with sync parameter in the RRC reconfiguration message to the terminal device 100 is optical (not mandatory).
For example, when the secondary node security key needs to be updated, the base station device 200 does not cause the SCG reconfiguration with sync parameter to be included, if the terminal device 100 is in SCG deactivation and an MN-terminated RLC bearer (associated with the master key) does not exist on the SCG side.
Also, if at least the third condition is satisfied and the terminal device 100 is not in SCG deactivation, the base station device 200 may determine that the inclusion of the SCG reconfiguration with sync parameter in the RRC reconfiguration message to the terminal device 100 is mandatory and thus always cause a SCG reconfiguration with sync parameter to be included. Also, if the terminal device 100 is in SCG deactivation, the base station device 200 may determine that the inclusion of the SCG reconfiguration with sync parameter in the RRC reconfiguration message to the terminal device 100 is optional (not mandatory) even when at least the third condition is satisfied, and thus does not cause the SCG reconfiguration with sync parameter to be included.
For example, the third condition may be that the AS security key derived from the secondary node security key (S-KgNB or S-KeNB) in NR-DC is changed, one or more radio bearers using the secondary key are configured for the terminal device 100, and these radio bearers are not released even when the processing associated with receiving an RRC reconfiguration request is performed.
In another example, the third condition may be that the base station device 200 performs MN handover in (NG)EN-DC.
In another example, the third condition may be that the base station device 200 performs SCG reactivation.
Also, if the RRC reconfiguration message to the terminal device 100 is to include a change of the AS security key derived from the master node security key (KgNB or KeNB) but not the SCG reconfiguration with sync parameter and if the terminal device 100 is not in SCG deactivation, the base station device 200 may determine to release all existing SCG RLC bearers associated with the radio bearers that use the master key and determine to release all existing SCG RLC bearers associated with the radio bearers that use the master key.
Also, if the RRC reconfiguration message to the terminal device 100 is to include a change of the AS security key derived from the master node security key (KgNB or KeNB) but not the SCG reconfiguration with sync parameter and if the terminal device 100 is in SCG deactivation, the base station device 200 may determine that it is unnecessary to release all existing SCG RLC bearers associated with the radio bearers that use the master key and determine that it is unnecessary to release all existing SCG RLC bearers associated with the radio bearers that use the master key.
Furthermore, the base station device 200 may cause the RRC reconfiguration message to include a parameter instructing to perform SCG reconfiguration with sync and a parameter instructing to perform SCG deactivation.
Note that including the SCG reconfiguration with sync parameter may refer to including the reconfiguration with sync parameter in the SCG configuration parameters. The radio bearer that uses the master key may be a radio bearer for which the parameter indicating whether to use the master key or the secondary key (keyToUse) is set to master (or primary). The radio bearer that uses the secondary key may be a radio bearer for which the parameter indicating whether to use the master key or the secondary key (keyToUse) is set to secondary.
Upon receiving an RRC reconfiguration message (S106), the terminal device 100 performs RRC reconfiguration message reception processing in SCG deactivation (S107). In the SCG deactivation RRC reconfiguration message reception processing in SCG deactivation S107, the terminal device 100 performs processing in accordance with the information (parameters) included in the RRC reconfiguration message.
The RRC reconfiguration message may include the following parameters,
If the received RRC reconfiguration message includes the reconfiguration with sync parameter, a predetermined condition is satisfied, and the SCG side radio bearers are suspended, the terminal device 100 resumes the UL communication of the suspended SCG side radio bearers. The predetermined condition may be that the terminal device 100 is not in SCG deactivation. Note that “a predetermined condition is satisfied” may be paraphrased as “it is determined whether a predetermined condition is satisfied, and if the predetermined condition is satisfied”. The predetermined condition may be any one of Conditions 1 to 3 below.
Furthermore, when the received RRC reconfiguration message includes the SCG reconfiguration with sync parameter, the terminal device 100 may perform the following processing.
The terminal device 100 may determine whether to immediately perform processing of SCG reconfiguration with sync from the SCG deactivation instruction in processing S104 or the parameter included in the RRC reconfiguration message in processing S106 (parameter indicating whether to immediately perform SCG reconfiguration with sync). For example, the terminal device 100 may immediately perform the processing if at least the first condition is not met, or may perform the processing at SCG reactivation if at least the first condition is met. Furthermore, after the terminal device 100 performs the above-described processing, it may return to in SCG deactivation.
The first condition is the first condition described for processing S103. That is, the first condition may be that conditions including all or some of Conditions 1 to 4 below are satisfied.
If the received RRC reconfiguration message includes a parameter instructing PDCP re-establishment, the terminal device 100 may immediately perform PDCP re-establishment, for example. In this case, if there is data for which transmission has not completed in PDCP of all or some of the radio bearers that satisfy at least the second condition, the terminal device 100 may transmit the data after SCG is reactivated.
Furthermore, the terminal device 100 may perform PDCP re-establishment of all or some of the radio bearers that satisfy at least the second condition after the SCG is reactivated. In this case, when the PDCP for which PDCP re-establishment is performed after SCG reactivation receives a PDCP SDU from upper layers, the PDCP does not perform processing associated with the PDCP SDU.
The second condition may be the second condition in processing 105, that is, being an SCG bearer or being a split bearer with a Primary Path set to the SCG.
In the processing of transmitting data for which transmission has not completed in PDCP, for an UM DRB, for example, the terminal device 100 regards the PDCP SDUs that have been assigned a sequence number but have not been passed to lower layers as the PDCP SDUs that are newly received from upper layers, and transmit them in order. In this case, the discard timer does not need to be restarted.
In the processing of transmitting data for which transmission has not completed in PDCP, for an AM DRB or an AM DRB in which the PDCP entity is not suspended, for example, the terminal device 100 transmits the PDCP SDUs for which successful transmission has not been confirmed from lower layers, and the PDCP SDUs that have been assigned a sequence number but have not been passed to lower layers in order.
Also, in the processing of transmitting data for which transmission has not completed in PDCP, for an AM DRB for the Uu interface (interface between the terminal device 100 and the base station device 200) in which the PDCP entity is suspended, for example, the terminal device 100 regards the PDCP SDUs for which successful transmission has not been confirmed from lower layers, and the PDCP SDUs that have been assigned a sequence number but have not been passed to lower layers as the PDCP SDUs that are newly received from upper layers and transmit them in order. In this case, the discard timer does not need to be restarted.
The discard timer may be a timer used to discard the corresponding PDCP SDU when it expires.
The base station device 200 may cause the RRC reconfiguration message in processing S106 to include a parameter indicating to immediately perform re-establishment processing for the PDCP of all or some radio bearers that satisfy at least the second condition (or perform it after SCG is reactivated). The terminal device 100 may determine from this parameter whether to perform the re-establishment processing for the PDCP of all or some of the radio bearers that satisfy at least the second condition immediately or after the SCG is reactivated.
If the received RRC reconfiguration message includes a parameter indicating QoS flow to DRB mapping rule configuration (mappedQoS-FlowToAdd), the terminal device 100 performs the following processing. The QoS flow to DRB mapping rule indicates the correspondence between a QoS flow and a DRB.
For example, the terminal device 100 may perform end marker processing if a predetermined condition is satisfied. The end marker processing is processing of constructing an end marker control PDU, mapping it to the DRB before change, and transmitting it to lower layers. Note that “a predetermined condition is satisfied” may be paraphrased as “it is determined whether a predetermined condition is satisfied, and the predetermined condition is satisfied”.
For example, assume that mappedQoS-FlowToAdd included in the received RRC reconfiguration message is a parameter for the first QoS flow.
The terminal device 100 performs the end marker processing if conditions including all or some of Conditions 1 to 3 below are satisfied, and if the DRB of the Qos flow to DRB mapping rule stored for the first QoS flow (that is, the DRB that is already stored and associated with the first QoS flow) is a DRB that does not correspond to second information received from the RRC of the terminal device 100 in processing S105. Also, even when conditions including all or some of Conditions 1 to 3 below are satisfied, the terminal device 100 does not perform the end marker processing if the DRB of the QoS flow to DRB mapping rule stored for the first QoS flow is a DRB that corresponds to the second information received from the RRC of the terminal device 100 in processing S105.
Also, in processing S105, if the second notification to the PDCP from the RRC of the terminal device 100 has been issued (if the PDCP has been identified as the PDCP of a radio bearer that satisfies at least the second condition), the terminal device 100 creates an end marker control PDU (SDAP Control PDU) and transmit it to PDCP. Upon receiving the SDAP Control PDU, the PDCP of the terminal device 100 discards the received SDAP Control PDU. Alternatively, if it is a split bearer with a Primary Path set to the SCG, the PDCP of the terminal device 100 may discard the SDAP Control PDU.
The base station device 200 may be implemented such that the end marker control PDU is not transmitted to the SCG when the terminal device 100 is in SCG deactivation. For example, the base station device 200 does not cause the RRC reconfiguration message that is to be transmitted to the terminal device 100 to include mappedQoS-FlowToAdd when the terminal device 100 is in SCG deactivation. For example, if the base station device 200 causes the RRC reconfiguration message that is to be transmitted to the terminal device 100 to include mappedQoS-FlowToAdd when the terminal device 100 is in SCG deactivation, the base station device 200 performs configuration such that the terminal device 100 does not transmit the end marker control PDU to the SCG side.
Also, if the terminal device 100 determines that the processing in accordance with the RRC reconfiguration message received from the base station device 200 is not possible, the terminal device 100 may initiate, with respect to the base station device 200, an RRC connection re-establishment procedure or a procedure regarding SCG radio link failure. For example, the terminal device 100 may determine that the processing in accordance with the received RRC reconfiguration message is not possible, if the RRC reconfiguration message received from the base station device 200 does not include the reconfiguration with sync parameter even though the message meets the condition with which the inclusion of the reconfiguration with sync parameter is mandatory. Also, the terminal device 100 may determine the processing in accordance with the received RRC reconfiguration message is not possible if the RRC reconfiguration message received from the base station device 200 causes end marker transmission to the SCG although the terminal device 100 is in SCG deactivation.
When UL data arrives (S108), the terminal device 100 performs UL data transmission processing in SCG deactivation (S109). The UL data transmission processing in SCG deactivation S109 is processing of determining whether to transmit the UL data to the master node or the secondary node and whether to transmit it immediately, for example, and transmitting the UL data at appropriate timing. The UL data transmission processing in SCG deactivation S109 is described below separately for a situation where a PDCP SDU arrives at PDCP, and for a situation where an MAC SDU arrives at MAC on the SCG side.
For example, in processing S105, if the second notification to the PDCP from the RRC of the terminal device 100 has been issued (if the PDCP has been identified as the PDCP of a radio bearer that satisfies at least the second notification), the PDCP of the terminal device 100 that detects arrival of a PDCP SDU notifies the RRC of the terminal device 100 of the generation of UL data. At this time, if it is a split bearer with a Primary Path set to the SCG, the terminal device 100 may notify the RRC of the terminal device 100 when a PDCP SDU is received from upper layers. In contrast, if it is a split bearer with a Primary Path set to the MCG, the terminal device 100 may notify the RRC of the terminal device 100 when the transmission data amount exceeds or is likely to exceed the threshold.
Upon receiving the notification of the generation of UL data from the PDCP of the terminal device 100, the RRC of the terminal device 100 transmits an SCG reactivation request to the base station device 200 (S110). The SCG reactivation request may be a message requesting to perform SCG reactivation, or a message including a parameter requesting to perform SCG reactivation.
The SCG reactivation request may also be an RRC message, for example. Furthermore, the SCG reactivation request may be SCG reactivation request of an RRC message, or may be a message with another name.
The processing of the RRC of the terminal device 100 is similar to that in the situation where a PDCP SDU arrives at the PDCP described above. Upon detecting the arrival of an MAC SDU, the MAC of the terminal device 100 notifies the RRC of the terminal device 100 of the generation of UL data. Also, the MAC of the terminal device 100 may perform SCG reactivation and prepare for transmitting the UL data (for example, perform a random access procedure with respect to the secondary node). The terminal device 100 may first perform the SCG reconfiguration with sync if there is SCG reconfiguration with sync that is not immediately performed in processing S107, for example. Also, the MAC of the terminal device 100 may perform all processing relating to SCG reactivation after receiving an SCG reactivation instruction from the base station device 200.
Furthermore, the MAC of the terminal device 100 may perform SCG reactivation and start transmitting the UL data without notifying the RRC of the terminal device 100 of the generation of UL data. Before starting the transmission of the UL data, the terminal device 100 may perform SCG reconfiguration with sync if there is SCG reconfiguration with sync that was not immediately performed in processing S107, for example
For example, if the SCG deactivation instruction received in processing S104 includes an instruction regarding the processing for UL data generation in SCG deactivation (such as whether SCG reactivation can be performed without transmission of an SCG reactivation request), the terminal device 100 may follow the instruction.
The base station device 200 determines whether SCG reactivation of the terminal device 100 is needed. The base station device 200 determines that SCG reactivation of the terminal device 100 is needed if conditions including some or all of the following Conditions 1 to 3 are met.
When determining that SCG reactivation is needed, the base station device 200 transmits to the terminal device 100 an SCG reactivation instruction to instruct (permit) to perform SCG reactivation (S111). The SCG reactivation instruction may be an RRC message. Also, the SCG reactivation instruction may be RRCReconfiguration of an RRC message or a message with another name.
Upon receiving the SCG reactivation instruction (S111), the terminal device 100 performs SCG reactivation processing (S112). The SCG reactivation processing S112 is processing in which the terminal device 100 reactivates the SCG.
The RRC of the terminal device 100 may transmit a third notification to the PDCP to which the second notification is transmitted in processing S105. The third notification may be a notification indicating SCG reactivation or a notification indicating SCG deactivation cancellation, and may be “SCG has been reactivated”, “SCG uplink transmission is permitted (resumed)”, or the like. Upon receiving the third notification, the PDCP of the terminal device 100 resumes UL transmission of the SCG.
Assume that the terminal device 100 is in SCG deactivation, Reflective QoS flow to DRB mapping Indication (RDI) is set to “1” in the SDAP entity of the terminal device 100, a downlink SDAP data PDU is received, and the received downlink SDAP data PDU includes a QoS flow identifier (QFI) for the second QoS flow. The downlink SDAP data PDU may be received via a DRB with an RLC bearer associated with the MCG.
The terminal device 100 performs the end marker processing if conditions including all or some of Conditions 1 to 3 below are satisfied, and the DRB of the QoS flow to DRB mapping rule stored for the second QoS flow (that is, the DRB that is already stored and associated with the first QoS flow) is a DRB that does not correspond to second information received from the RRC of the terminal device 100 in the first embodiment. Also, even when conditions including all or some of Conditions 1 to 3 below are satisfied, the terminal device 100 does not perform the end marker processing if the DRB of the QoS flow to DRB mapping rule stored for the second Qos flow is a DRB that corresponds to the second information received from the RRC of the terminal device 100. The end marker processing is processing of constructing an end marker control PDU, mapping it to the DRB before change, and transmitting it to lower layers.
When the terminal device 100 receives a RRC reconfiguration message and the RRC reconfiguration message message includes the SCG reconfiguration with sync parameter, the terminal device 100 determines whether to immediately perform part of all of processing of SCG reconfiguration with sync. When the terminal device 100 determines that part or all of the processing of SCG reconfiguration with sync is not to be performed immediately, it performs, at SCG reactivation, the processing of SCG reconfiguration with sync that is not performed. The terminal device 100 may determine not to perform immediately when some or all of the following conditions are met, for example.
The SCG reconfiguration with sync is associated with a change of the secondary node security key (S-KgNB or S-KeNB) or a change of the AS security key derived from the secondary node security key.
Furthermore, if the base station device 200 determines that it does not want the SCG of the terminal device 100 to immediately perform SCG reconfiguration with sync, the base station device 200 does not cause the reconfiguration with sync parameter to be included in the SCG configuration parameters in the RRC reconfiguration message. The base station device 200 determines that it does not want immediate execution when a condition including some or all of the following conditions is met.
This limits the implementation of SCG reactivation caused when reconfiguration with sync is performed, thereby limiting the power consumption of the terminal device 100.
Furthermore, if the RRC reconfiguration message received from the base station device 200 in SCG deactivation includes the MCG reconfiguration with sync parameter but not the SCG reconfiguration with sync, the terminal device 100 does not resume UL transmission of the SCG.
This limits the implementation of SCG reactivation caused when reconfiguration with sync is performed, thereby limiting the power consumption of the terminal device 100.
Also, upon receiving an SCG deactivation instruction from the base station device 200, the terminal device 100 performs Processing A on radio bearers that meet Condition A.
Condition A is being an SCG bearer, or being a split bearer with a Primary Path set to the SCG.
Processing A is processing of immediately transmitting or discarding data for which transmission has not completed in the PDCP entity of a radio bearer that satisfies Condition A. Also, Processing A may be processing in which, when a request for re-establishment of the PDCP entity of a radio bearer that satisfies Condition A is issued, the transmission of the data for which transmission has not completed in the process of the PDCP entity re-establishment is not immediately performed but is performed at (after) SCG reactivation. Furthermore, Processing A may be processing of discarding an SDAP Control PDU when the PDCP entity of a radio bearer that satisfies Condition A receives the SDAP Control PDU from upper layers.
This limits the implementation of SCG reactivation due to the occurrence of UL transmission, thereby limiting the power consumption of the terminal device 100.
Furthermore, when the RRC of the terminal device 100 receives an SCG deactivation instruction from the base station device 200, it notifies the SDAP associated with the radio bearer (DRB) that satisfies Condition A of Information A.
Information A is information indicating that UL transmission is not possible with the DRB, such as that UL transmission is prohibited (stopped) with the DRB, or that the cell group associated with the DRB is in deactivation.
This limits the implementation of SCG reactivation due to the occurrence of UL transmission, thereby limiting the power consumption of the terminal device 100.
Furthermore, in SDAP, if the DRB associated with the first QoS flow is changed and the DRB before the change is the DRB that is notified from RRC, the terminal device 100 does not transmit the SDAP Control SDU to the DRB before the change.
Also, the base station device 200 may be implemented such that an end marker is not generated when the terminal device 100 is in SCG deactivation. For example, in SCG deactivation, the base station device 200 may control such that an end marker is not generated by controlling such that the QoS flow that is associated with a DRB that is an SCG bearer or a split bearer with a Primary Path set to the SCG is not re-associated with another DRB. Furthermore, before the SCG deactivation instruction of processing 104 or at the SCG deactivation instruction in the first embodiment, the base station device 200 may control such that an end marker is not generated by controlling such that all or some of the QoS flows associated with a DRB that satisfies at least the second condition are (re-)associated with a DRB that does not satisfy at least the second condition, for example.
This limits the implementation of SCG reactivation due to the occurrence of UL transmission, thereby limiting the power consumption of the terminal device 100.
Furthermore, the base station device 200 may instruct (specify) whether the terminal device 100 issues an SCG reactivation request to the base station device when UL data is generated (arrived) or the terminal device 100 spontaneously performs SCG reactivation. For example, the terminal device 100 performs the following processing.
Upon receiving an SCG deactivation instruction from the base station device 200, the RRC of the terminal device 100 transmits Notification A to the PDCP entity of the radio bearer that meets Condition A. Notification A is a notification indicating that the SCG is deactivated or that UL transmission on the SCG side is prohibited (interrupted). When the PDCP entity of the radio bearer that meets Condition A receives data from upper layers, the PDCP entity of the terminal device 100 notifies the RRC of the terminal device 100 that UL data is generated. The RRC of the terminal device 100 generates an SCG deactivation request and transmits it to the base station device 200. Upon receiving an SCG reactivation message from the base station device 200, the RRC of the terminal device 100 transmits a notification indicating that the SCG is reactivated or that UL transmission on the SCG side is initiated (resumed) to the PDCP entity of the radio bearer to which the second notification is transmitted.
Alternatively, when UL data is generated in the MAC, the terminal device 100 performs a random access procedure to enable UL transmission. The terminal device 100 first performs any SCG reconfiguration with sync that was not performed immediately.
This allows the terminal device 100 to perform appropriate processing when UL transmission to and RLC bearer on the SCG side occurs in SCG deactivation. As such, the terminal device 100 can notify the base station device 200 that UL transmission has occurred on the SCG side RLC bearer in SCG deactivation, and perform SCG reactivation autonomously or by an instruction from the base station device 200.
Each embodiment may be combined. The messages in the sequence do not need to be performed in order, and the order may be rearranged. Also, some messages in the sequence may not be performed. For example, the processing in SCG deactivation in the terminal device 100 may be performed as long as the terminal device 100 is in SCG deactivation, and messages in the sequence may be omitted.
In each embodiment, functions and processing described as those of the terminal device 100 may be functions and processing of the base station device 200. In each embodiment, functions and processing described as those of the base station device 200 may be functions and processing of the terminal device 100.
In each embodiment, “radio bearers” may be signaling radio bearers, data radio bearers, or both signaling radio bearers and data radio bearers.
A summary is given below.
A first radio communication device (terminal device 100) including: a reception unit configured to perform reception from a second radio communication device (base station device 200); a transmission unit configured to perform transmission to the second radio communication device; and a processing unit, wherein the processing unit is configured to, when a first RRC message transmitted from an opposing radio communication device includes a parameter regarding SCG deactivation, deactivate the SCG and perform first processing on a radio bearer that satisfies a first condition among radio bearers established for the first radio communication device.
A first radio communication device, wherein the first condition is being an SCG bearer or being a split bearer with a primary path set to the SCG side.
A first radio communication device, wherein the first processing is processing of immediately transmitting data for which transmission has not completed in the PDCP entity of a radio bearer that satisfies the first condition.
A first radio communication device, wherein the first processing is processing of discarding all data for which transmission has not completed in the PDCP entity of a radio bearer that satisfies the first condition.
A first radio communication device, wherein, while the SCG is deactivated, the processing unit is further configured to, when a request is issued for re-establishment of the PDCP entity of a radio bearer that satisfies the first condition among the radio bearers established for the first radio communication device, refrain from transmitting data for which transmission has not completed in re-establishment processing of the PDCP entity, and when a request is issued for re-establishment of the PDCP entity of a radio bearer that does not satisfy the first condition among the radio bearers established for the first radio communication device, transmit data for which transmission has not completed in re-establishment processing of the PDCP entity.
A second radio communication device including: a second transmission unit configured to perform transmission to a first radio communication device; a second reception unit configured to perform reception from the first radio communication device; and a second processing unit, wherein the second processing unit is configured to, when a secondary cell group configured for the first radio communication device is to be deactivated, deactivate the SCG by causing a first RRC message that is to be transmitted from the second transmission unit to include a parameter regarding SCG deactivation, and cause first processing to be performed on a radio bearer that satisfies a first condition among radio bearers established for the first radio communication device.
A second radio communication device including: a second transmission unit configured to perform transmission to a first radio communication device; a second reception unit configured to perform reception from the first radio communication device; and a second processing unit, wherein the second processing unit is configured to cause an RRC reconfiguration message that is to be transmitted to the first radio communication device to include a parameter indicating that the SCG reconfiguration with sync parameter included in the RRC reconfiguration message is not to be performed immediately but is to be performed after SCG reactivation.
A first radio communication device including: a transmission unit configured to perform transmission to the second radio communication device; a reception unit configured to perform reception from the second radio communication device; and a processing unit, wherein the processing unit is configured to, when an RRC reconfiguration message received from the second radio communication device includes a parameter indicating that the SCG reconfiguration with sync parameter included in the RRC reconfiguration message is not to be performed immediately but is to be performed after SCG reactivation, perform a procedure of reconfiguration with sync in accordance with the SCG reconfiguration with sync parameter after SCG reactivation, and, when a parameter indicating that the SCG reconfiguration with sync parameter included in the RRC reconfiguration message is not to be performed immediately but is to be performed after SCG reactivation is not included, immediately perform a procedure of reconfiguration with sync in accordance with the SCG reconfiguration with sync parameter.
A second radio communication device including: a second transmission unit configured to perform transmission to a first radio communication device; a second reception unit configured to perform reception from the first radio communication device; and a second processing unit, wherein when the second processing unit transmits an RRC reconfiguration message to the first radio communication device, the second processing unit is configured to, when a second condition is satisfied, always cause the RRC reconfiguration message to include a SCG reconfiguration with sync parameter, and when the second condition is not satisfied, causes the RRC reconfiguration message to include a SCG reconfiguration with sync parameter if necessary.
A second radio communication device, wherein the second condition is a condition that it is a change of an AS security key derived from a secondary node security key in NR-DC, at least one of radio bearers set to the first communication device has a secondary key, at least one radio bearer is not released by the RRC reconfiguration message, and the SCG is not deactivated.
A second radio communication device, wherein the second condition is a condition that it is a master node handover in EN-DC, and the SCG is not deactivated.
A second radio communication device, wherein the second condition is a condition that it is reactivation of the SCG.
A first radio communication device including: a transmission unit configured to perform transmission to the second radio communication device; a reception unit configured to perform reception from the second radio communication device; and a processing unit, wherein the processing unit is configured to, when an RRC reconfiguration message received from the second radio communication device includes a reconfiguration with sync parameter and a third condition is satisfied, resume uplink transmission of an SCG radio bearer that is suspended.
A first radio communication device, wherein the third condition is a condition that it is a procedure initiated by an MCG configuration parameter, and the SCG is not deactivated.
A first radio communication device, wherein the third condition is a condition that it is a procedure initiated by an SCG configuration parameter.
A second radio communication device including: a second transmission unit configured to perform transmission to a first radio communication device; a second reception unit configured to perform reception from the first radio communication device; and a second processing unit, wherein the second processing unit is configured to, when a secondary cell group configured for the first radio communication device is to be deactivated, cause a first RRC message that is to be transmitted from the second transmission unit to include a parameter regarding SCG deactivation to cause RRC of the first radio communication device to issue a first notification to an SDAP entity associated with a radio bearer that satisfies a fourth condition among radio bearers established for the first radio communication device.
A second radio communication device, wherein the fourth condition is being an SCG bearer or being a split bearer with a primary path set to the SCG.
A second radio communication device, wherein the first notification is a notification indicating that uplink transmission of a radio bearer that satisfies the fourth condition is suspended.
A second radio communication device, wherein the first notification is issued when the SDAP entity is associated with a radio bearer that satisfies the fourth condition.
A first radio communication device including: a transmission unit configured to perform transmission to the second radio communication device; a reception unit configured to perform reception from the second radio communication device; and a processing unit, wherein the processing unit is configured to, when a first RRC message that is to be transmitted from the second transmission unit of the second radio communication device includes a parameter regarding SCG deactivation, deviate the SCG, and RRC of the first radio communication device is configured to issue a first notification to an SDAP entity associated with a radio bearer that satisfies a fourth condition among radio bearers established for the first radio communication device.
A first radio communication device, wherein the fourth condition is being an SCG bearer or being a split bearer with a primary path set to the SCG.
A first radio communication device, wherein the first notification is a notification indicating that uplink transmission of a radio bearer that satisfies the fourth condition is suspended.
A first radio communication device, wherein the first notification is issued when the SDAP entity is associated with a radio bearer that satisfies the fourth condition.
A second radio communication device including: a second transmission unit configured to perform transmission to a first radio communication device; a second reception unit configured to perform reception from the first radio communication device; and a second processing unit, wherein the second processing unit is configured to, when a secondary cell group configured for the first radio communication device is to be deactivated, deactivate the SCG by causing a first RRC message that is to be transmitted from the second transmission unit to include a parameter regarding SCG deactivation, and cause first processing to be performed on a radio bearer that satisfies a first condition among radio bearers established for the first radio communication device.
A second radio communication device, wherein the first condition is being an SCG bearer or being a split bearer and a primary path is set in the SCG.
A second radio communication device, wherein the first processing is transmitting a message for requesting SCG reactivation to the first radio communication device when uplink data is generated for a radio bearer that satisfies a first condition.
A first radio communication device including: a reception unit configured to perform reception from the second radio communication device; a transmission unit configured to perform transmission to the second radio communication device; and a processing unit, wherein the processing unit is configured to, when a first RRC message transmitted from a second transmission unit of the second radio communication device includes a parameter regarding SCG deactivation, deactivate the SCG and perform first processing on a radio bearer that satisfies a first condition among radio bearers established for the first radio communication device.
A first radio communication device, wherein the first condition is being an SCG bearer or being a split bearer and a primary path is set in the SCG.
A first radio communication device, wherein the first processing is transmitting a message for requesting SCG reactivation to the second radio communication device when uplink data is generated for a radio bearer that satisfies a first condition.
One disclosure allows for the limitation of power consumption of a terminal device in activating communication between the terminal device for which the secondary cell group is in an inactive state and a secondary base station device in MR-DC.
All examples and conditional language provided herein are intended for the pedagogical purposes of aiding the reader in understanding the disclosure and the concepts contributed by the inventor to further the art, and are not to be construed as limitations to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the disclosure. Although one or more embodiments of the present disclosure have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the disclosure.
This application is a continuation application of International Application PCT/JP2021/038389 filed on Oct. 18, 2021, and designated the U.S., the entire contents of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2021/038389 | Oct 2021 | WO |
| Child | 18630652 | US |
