Terminal device, method, and integrated circuit

Abstract

To provide a terminal device, a method, and an integrated circuit, capable of efficiently performing communication control.SOLUTION: A terminal device that communicates with a base station device, is configured to: when detecting a radio link failure of a direct path, determine whether or not an indirect path change procedure is in progress; and based on determining that the indirect path change procedure is not in progress, report the radio link failure of the direct path to the base station device. Therein: the direct path is a path that connects to the base station device via a Uu interface; and the indirect path is a path that connects to the base station device via a relay terminal device.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a terminal device, a method, and an integrated circuit.

Background Art

[0002] In the 3rd Generation Partnership Project (3GPP[registered trademark]), which is a standardization project for cellular mobile communication systems, technical studies and standardization of cellular mobile communication systems including radio access, core network, services, etc. are being carried out. In 3GPP, for example, E-UTRA (Evolved Universal Terrestrial Radio Access) was started for technical studies and standardization as a radio access technology (RAT) for cellular mobile communication systems for the 3.9th and 4th generations. Even now, in 3GPP, technical studies and standardization of extended technologies of E-UTRA are being carried out. Note that E-UTRA is also referred to as Long Term Evolution (LTE[registered trademark]), and extended technologies may be referred to as LTE-Advanced (LTE-A), LTE-Advanced Pro (LTE-A Pro).

[0003]

[0004] Also, in 3GPP, NR (New Radio, or NR Radio access) was started for technical studies and standardization as a radio access technology (RAT) for cellular mobile communication systems for the 5th generation (5G). Even now, in 3GPP, technical studies and standardization of extended technologies of NR are being carried out.

Prior Art Documents

Non-Patent Documents

[0005] [Non-Patent Document 1] 3GPP TS 38.331 v18.0.0, "Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specifications" [Non-Patent Document 2] 3GPP TS 38.321 v18.0.0, "NR; Medium Access Control (MAC) protocol specification" pp17 - 104 [Non-Patent Document 3] 3GPP TS 38.213 v17.1.0, "NR; Physical layer procedures for control" pp14 - 20 [Non-Patent Document 4] 3GPP TS 38.300 v18.0.0, "NR; NR and NG-RAN Overall Description; Stage 2" [Non-Patent Document 5] 3GPP TS 38.351 v17.1.0, "NR; Sidelink Relay Adaptation Protocol (SRAP) Specification" [Summary of the Invention] [Problems to be Solved by the Invention]

[0006] In 3GPP, as an extended technology of NR, a technology called sidelink (SL) is being studied, in which terminal devices communicate directly with each other without going through the core network. Also, a technology called UE-to-Network Relay (U2N Relay) has been studied, in which a relay terminal device provides communication via the sidelink, enabling a terminal device to communicate with a base station device via the relay terminal device. Furthermore, a technology called Multi-path Relay is starting to be studied, which uses two (or more) types of paths to communicate with a base station device: an indirect path that uses U2N Relay to communicate with the base station device and a direct path that communicates directly with the base station device without using U2N Relay. The study of a technology called Multi-path Relay, which communicates with a base station device, has begun.

[0007] One aspect of the present invention has been made in view of the above circumstances, and one of its objectives is to provide a terminal device, a base station device, a communication method, and an integrated circuit that can efficiently perform communication control.

Means for Solving the Problems

[0008] To achieve the above objective, one aspect of the present invention has taken the following means. That is, one aspect of the present invention is a terminal device that communicates with a base station device, having a receiving unit, a transmitting unit, and a processing unit. When the processing unit detects a radio link failure of a direct path, it determines whether a procedure for changing the indirect path is in progress. Based on the determination that the procedure for changing the indirect path is not in progress, it reports the radio link failure of the direct path to the base station device. The direct path is a path connected to the base station device via the Uu interface, and the indirect path is a path connected to the base station device via a relay terminal device.

[0009] Another aspect of the present invention is a method for a terminal device communicating with a base station device, the method including the steps of: determining whether a non-direct path change procedure is in progress when detecting a radio link failure of a direct path; and reporting the radio link failure of the direct path to the base station device based on the determination that the non-direct path change procedure is not in progress. The direct path is a path connecting to the base station device using a Uu interface, and the non-direct path is a path connecting to the base station device via another terminal device.

[0010] Another aspect of the present invention is an integrated circuit implemented in a terminal device that communicates with a base station device, the integrated circuit having a function of determining whether a non-direct path change procedure is in progress when a radio link failure of a direct path is detected, and a function of reporting the radio link failure of the direct path to the base station device based on the determination that the non-direct path change procedure is not in progress. The direct path is a path connecting to the base station device using a Uu interface, and the non-direct path is a path connecting to the base station device via another terminal device.

[0011] These comprehensive or specific aspects may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium. [Effects of the Invention]

[0012] According to one aspect of the present invention, a terminal device, a method, and an integrated circuit can realize efficient communication control processing. [Brief explanation of the drawings]

[0013]

Figure 1

Figure 2

Figure 3

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Figure 9

Figure 10

Mode for Carrying Out the Invention

[0014] Hereinafter, this embodiment will be described in detail with reference to the drawings.

[0015] In this embodiment, the names of each node and entity in the case where the radio access technology is NR, and the processing in each node and entity will be described. However, this embodiment may be applied to other radio access technologies. The names of each node and entity in this embodiment may be other names.

[0016] FIG. 1 is a schematic diagram of the communication system according to this embodiment. Note that the functions of each node, radio access technology, core network, interface, etc. described with reference to FIG. 1 are some functions closely related to this embodiment, and may have other functions.

[0017] E-UTRA may be a radio access technology. Also, E-UTRA may be an air interface between UE122 and ng-eNB100. The air interface between UE122 and ng-eNB100 The face 112 may be referred to as the Uu interface. The ng-eNB (ng E-UTRAN Node B) 100 may be a base station device of the E-UTRAN. The ng-eNB 100 may have the E-UTRA protocol described later. The E-UTRA protocol may be composed of the E-UTRA User Plane (UP) protocol and the E-UTRA Control Plane (CP) protocol described later. The ng-eNB 100 may terminate the E-UTRA user plane protocol and the E-UTRA control plane protocol for the UE 122. The radio access network composed of eNBs may also be referred to as the E-UTRAN. The radio access technology may be NR. Also, NR may be the air interface between the UE 122 and the gNB 102. The air interface 112 between the UE 122 and the gNB 102 may be referred to as the Uu interface. The gNB (g Node B) 102 may be a base station device of NR. The gNB 102 may have the NR protocol described later. The NR protocol may be composed of the NR User Plane (UP) protocol and the NR Control Plane (CP) protocol described later. The gNB 102 may terminate the NR user plane protocol and the NR control plane protocol for the UE 122.

[0018] Note that the interface 110 between the ng-eNB 100 and the gNB 102 may be referred to as the Xn interface. Also, the ng-eNB and the gNB may be connected to the 5GC via an interface called the NG interface (not shown). The 5GC may be the core network. One or more base station devices may be connected to the 5GC via the NG interface.

[0019]

[0020] ​​​The state in which a base station can be connected only via the Uu interface may be called Inside NG-RAN Coverage or In-Coverage (IC). The state in which it is not possible to connect to the device is called Outside NG-RAN Coverage or Out-of-Coverage (OoC). The air interface 114 between the UEs 122 may be referred to as a PC5 interface. Communication between the UEs 122 via the PC5 interface may be referred to as sidelink (SL) communication. Furthermore, a terminal device capable of performing sidelink communication may be referred to as a sidelink communication-capable terminal device.

[0021] In the following description, the ng-eNB 100 and / or the gNB 102 will also be referred to simply as a base station device, and the UE 122 will also be referred to simply as a terminal device or a UE. The PC5 interface will also be referred to simply as a PC5. The Uu interface is also referred to simply as Uu.

[0022] Sidelink is a technology that enables direct communication between terminal devices via PC5, and sidelink transmission and reception on PC5 is performed inside and outside the NG-RAN coverage.

[0023] There are three transmission modes for NR SL communication, and SL communication is performed in one of the transmission modes by a pair of Source Layer-2 (L2) ID and Destination Layer-2 (L2) ID. The Source Layer-2 ID and Destination Layer-2 ID are respectively called Source L2ID. , may be referred to as destination L2 ID. The three transmission modes are "Unicast transmission", "Groupcast transmission", and "Broadcast It is "Broadcast transmission". Note that the transmission mode may be referred to as a cast type or the like. Note that unicast transmission of direct communication is supported on the PC5, and a PC5 unicast link between two UEs may be established for direct communication. Also, the PC5 unicast link may be maintained, changed, or released according to application layer requests or communication requirements.

[0024] Unicast transmission is characterized by (1) supporting one PC5-RRC connection between a paired UE, (2) transmitting and receiving control information and user traffic between UEs on the sidelink, (3) supporting sidelink HARQ feedback, (4) performing transmission power control on the sidelink, (5) supporting RLC AM, and (6) detecting radio link failure for the PC5-RRC connection.

[0025] Also, group cast transmission is characterized by (1) transmitting and receiving user traffic between UEs belonging to a sidelink group and (2) supporting sidelink HARQ feedback.

[0026] Also, broadcast transmission is characterized by (1) transmitting and receiving user traffic between UEs on the sidelink .

[0027] Figures 2 and 3 are diagrams of an example of the protocol architecture in NR sidelink communication according to this embodiment. Note that the functions of each protocol described using Figures 2 and / or 3 are some functions closely related to this embodiment and may have other functions. Note that in this embodiment, a sidelink (SL) may be a link between terminal devices.

[0028] ​Figure 2(A) is a diagram of the protocol stack of the control plane (CP) for SCCH using RRC configured on the PC5 interface. As shown in Figure 2(A), the control plane protocol stack for SCCH using RRC consists of the PHY (Physical layer) 200 which is the radio physical layer, the MAC (Medium Access Control) 202 which is the medium access control layer, the RLC (Radio Link Control) 204 which is the radio link control layer, and the PDCP (Packet Data Convergence Protocol) 206 which is the packet data convergence protocol layer, and the RRC (Radio Resource Control) 208 which is the radio resource control layer. It may be composed of. Also, Figure 2(B) is a diagram of the protocol stack of the control plane for SCCH using PC5-S configured on the PC5 interface. As shown in Figure 2(B), the control plane protocol stack for SCCH using PC5-S consists of the PHY (Physical layer) 200 which is the radio physical layer, the MAC (Medium Access Control) 202 which is the medium access control layer, the RLC (Radio Link Control) 204 which is the radio link control layer, and the PDCP (Packet Data Convergence Protocol) 206 which is the packet data convergence protocol layer, and the PC5-S (PC5 Signalling) 210 which is the PC5 signalling layer. It may be composed of.

[0029] Figure 3(A) is a diagram of the protocol stack of the control plane for SBCCH configured on the PC5 interface. As shown in Figure 3(A), the control plane protocol stack for SBCCH may be composed of PHY (Physical layer) 200 which is the radio physical layer, MAC (Medium Access Control) 202 which is the medium access control layer, RLC (Radio Link Control) 204 which is the radio link control layer, and RRC (Radio Resource Control) 208 which is the radio resource control layer. Also Figure 3(B) is a diagram of the protocol stack of the user plane (User Pla ne:UP) for STCH configured on the PC5 interface. As shown in Figure 3(B), the control plane protocol stack for STCH may be composed of PHY (Physical layer) 200 which is the radio physical layer, MAC (Medium Access Control) 202 which is the medium access control layer, RLC (Radio Link Control) 204 which is the radio link control layer, PDCP (Packet Data Convergence Protocol) 206 which is the packet data convergence protocol layer, and SDAP (Service Data Adaptation Protocol) 310 which is the service data adaptation protocol layer. Note that the AS (Access Stratum) layer may be a layer that includes some or all of PHY200, MAC202, RLC204, PDCP206, SDAP310, and RRC208. Also, PC5-S210 and Discovery400 described later may be layers above the AS layer.

[0030]

[0031] ​In this embodiment, terms such as PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), SDAP (SDAP layer), RRC (RRC layer), and PC5-S (PC5-S layer) may be used. In this case, PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), SDAP (SDAP layer), RRC (RRC layer), and PC5-S (PC5-S layer) may be the PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), SDAP (SDAP layer), RRC (RRC layer), and PC5-S (PC5-S layer) of the NR sidelink protocol, respectively. Note that when performing sidelink communication using the technology of E-UTRA, the SDAP layer may not be necessary. Note that in order to clarify that it is a protocol for sidelink, for example, RLC may be expressed as sidelink RLC, SL RLC, PC5 RLC, etc., and for other protocols, it may also be expressed that it is a protocol for sidelink by attaching "sidelink", "SL", or "PC5" at the beginning.

[0032] Also, in this embodiment, when distinguishing between the protocols of E-UTRA and NR hereinafter, PHY, MAC, RLC, PDCP, and RRC may be referred to as PHY for E-UTRA or PHY for LTE, MAC for E-UTRA or MAC for LTE, RLC for E-UTRA or RLC for LTE, PDCP for E-UTRA or PDCP for LTE, and RRC for E-UTRA or RRC for LTE, respectively. Also, PHY, MAC, RLC, PDCP, and RRC may be described as PHY for E-UTRA or PHY for LTE, MAC for E-UTRA or MAC for LTE, RLC for E-UTRA or RLC for LTE, PDCP for E-UTRA or PDCP for LTE, and RRC for E-UTRA or RRC for LTE, etc. respectively in some cases as well. Also, when distinguishing between the protocols of E-UTRA and NR, PHY, MAC, RLC, PDCP, and RRC may be referred to as PHY for NR, MAC for NR, RLC for NR, RLC for NR, and RRC for NR, respectively Yes. In some cases, PHY, MAC, RLC, PDCP, and RRC may be described as NR PHY, NR MAC, NR RLC, NR PDCP, NR RRC, etc., respectively.

[0033] Entities in the AS layer of E-UTRA, NR, and / or sidelink will be described. An entity having some or all of the functions of the physical layer may be called a PHY entity. An entity having some or all of the functions of the MAC layer may be called a MAC entity. An entity having some or all of the functions of the RLC layer may be called an RLC entity. An entity having some or all of the functions of the PDCP layer may be called a PDCP entity. An entity having some or all of the functions of the SDAP layer may be called an SDAP entity. An entity having some or all of the functions of the RRC layer may be called an RRC entity. The PHY entity, MAC entity, RLC entity, PDCP entity, SDAP entity, and RRC entity may be alternatively referred to as PHY, MAC, RLC, PDCP, SDAP, and RRC, respectively. Also, each entity in the AS layer may be a common entity for E-UTRA, NR, and / or sidelink, or may be an independent entity.

[0034] Note that the data provided by the lower layers to MAC, RLC, PDCP, SDAP, and / or the data provided by the lower layers to MAC, RLC, PDCP, SDAP may be called MAC PDU (Protocol Data Unit), RLC PDU, PDCP PDU, SDAP PDU, respectively. Also, the data provided by the upper layers to MAC, RLC, PDCP, SDAP, and / or the data provided by MAC, RLC, PDCP, SDAP to the upper layers The data can be referred to as MAC SDU (Service Data Unit), RLC SDU, PDCP SDU, and SDAP SDU, respectively. Also, the segmented RLC SDU can be referred to as an RLC SDU segment.

[0035] Here, the base station device and the terminal device exchange (transmit and receive) signals in the upper layer (higher layer) on the Uu interface. The higher layer may also be referred to as the upper layer and can be paraphrased with each other. For example, the base station device and the terminal device may transmit and receive RRC messages (also referred to as RRC messages and RRC signalling) in the Radio Resource Control (RRC) layer. Also, the base station device and the terminal device may transmit and receive MAC Control Elements (MAC CE) in the MAC (Medium Access Control) layer. The RRC layer of the terminal device obtains the system information notified by the base station device. Here, the RRC message, the system information, and / or the MAC control element are also referred to as upper layer signals (higher layer signaling) or upper layer parameters (higher layer parameter). Each parameter included in the upper layer signal received by the terminal device may also be referred to as an upper layer parameter. For example, in the processing of the PHY layer, the upper layer means the upper layer as seen from the PHY layer, and may mean one or more of the MAC layer, RRC layer, RLC layer, PDCP layer, NAS (Non Access Stratum) layer, etc. For example, in the processing of the MAC layer, the upper layer may mean one or more of the RRC layer, RLC layer, PDCP layer, NAS layer, etc. The RRC layer of the terminal device obtains the system information notified by the base station device. Here, the RRC message, the system information, and / or the MAC control element are also referred to as upper layer signals (higher layer signaling) or upper layer parameters (higher layer parameter). Each parameter included in the upper layer signal received by the terminal device may also be referred to as an upper layer parameter. For example, in the processing of the PHY layer, the upper layer means the upper layer as seen from the PHY layer, and may mean one or more of the MAC layer, RRC layer, RLC layer, PDCP layer, NAS (Non Access Stratum) layer, etc. For example, in the processing of the MAC layer, the upper layer may mean one or more of the RRC layer, RLC layer, PDCP layer, NAS layer, etc.

[0036] Also, between terminal devices, signals are exchanged (transmitted and received) at the upper layer (higher layer) on the PC5 interface. Terminal devices may exchange RRC messages (also referred to as RRC messages or RRC signalling) in the Radio Resource Control (RRC) layer. Also, terminal devices may exchange MAC Control Elements (MAC CE) in the MAC (Medium Access Control) layer. Here, RRC messages and / or MAC control elements are also referred to as higher layer signals or higher layer parameters. Each parameter included in the higher layer signal received by the terminal device may be referred to as a higher layer parameter. For example, in the processing of the PHY layer, the upper layer means the upper layer as seen from the PHY layer, and may mean one or more of the MAC layer, RRC layer, RLC layer, PDCP layer, PC5-S layer, Discovery layer, etc. For example, in the processing of the MAC layer, the upper layer may mean one or more of the RRC layer, RLC layer, PDCP layer, PC5-S layer, Discovery layer, etc. In the layer, MAC control elements (MAC CE) may be transmitted and received. Here, the RRC message and / or the MAC control element are also referred to as higher layer signals or higher layer parameters. Each parameter included in the higher layer signal received by the terminal device may be referred to as a higher layer parameter. For example, PHY In the processing of the layer, the upper layer means the upper layer as seen from the PHY layer, and thus may mean one or more of the MAC layer, RRC layer, RLC layer, PDCP layer, PC5-S layer, Discovery layer, etc. For example, MAC In the processing of the layer, the upper layer may mean one or more of the RRC layer, RLC layer, PDCP layer, PC5-S layer, Discovery layer, etc.

[0037] Hereinafter, the meaning of "A is given (provided) by the upper layer" or "A is given (provided) by the upper layer" may mean that the upper layer (mainly the RRC layer, MAC layer, etc.) of the terminal device receives A from the base station device or another terminal device, and the received A is given (provided) from the upper layer of the terminal device to the physical layer of the terminal device. For example, in the terminal device, "being provided with upper layer parameters" may mean receiving an upper layer signal from the base station device or another terminal device, and the upper layer parameters included in the received upper layer signal are provided from the upper layer of the terminal device to the physical layer of the terminal device. That the upper layer parameters are set in the terminal device may also mean that the upper layer parameters are given (provided) to the terminal device. For example, that the upper layer parameters are set in the terminal device may mean that the terminal device receives an upper layer signal from the base station device or another terminal device and sets the received upper layer parameters in the upper layer. However, that the upper layer parameters are set in the terminal device may also include setting the default parameters pre-given to the upper layer of the terminal device. When explaining that the terminal device transmits an RRC message to the base station device or another terminal device, the expression of submitting a message from the RRC entity of the terminal device to the lower layer (lower layer) may be used. In the terminal device, when the RRC entity "submits a message to the lower layer", it may mean submitting the message to the PDCP layer. In the terminal device, when the RRC layer "submits a message to the lower layer", since the RRC message is transmitted using SRBs (such as SRB0, SRB1, SRB2, SRB3, etc.), it may mean submitting it to the PDCP entity corresponding to each SRB. When the RRC entity of the terminal device receives an indication from the lower layer, the lower layer may mean one or more of the PHY layer, MAC layer, RLC layer, PDCP layer, etc.

[0038] Describe an example of the functions of the PHY. The PHY of the terminal device may have a function of transmitting and receiving data transmitted via a sidelink (SL) physical channel with the PHY of another terminal device. The PHY may be connected to the upper-layer MAC via a transport channel. The PHY may deliver data to the MAC via the transport channel. Also, the PHY may be provided with data from the MAC via the transport channel. In the PHY, an RNTI (Radio Network Temporary Identifier) may be used to identify various control information. Here, describe the physical channels. The physical channels used for wireless communication between the terminal device and another terminal device may include the following physical channels. PSBCH (Physical Sidelink Broadcast CHannel) PSCCH (Physical Sidelink Control CHannel)

[0039] PSBCH may be used to notify the system information required by the terminal device.

[0040] PSCCH may be used to indicate resources and other transmission parameters related to the PSSCH. PSSCH (Physical Sidelink Shared CHannel) PSFCH (Physical Sidelink Feedback CHannel)

[0041]

[0042]

[0043] ​​​The PSSCH may be used to transmit data and control information regarding HARQ / CSI feedback to other terminal devices.

[0044] The PSFCH may be used to carry HARQ feedback to other terminal devices.

[0045] An example of the function of the MAC will be described. The MAC may be referred to as the MAC sublayer. The MAC may have a function of mapping various logical channels to corresponding transport channels. The logical channels may be identified by logical channel identifiers (Logical Channel Identity, or Logical Channel ID). The MAC may be connected to the upper RLC via a logical channel. The logical channels may be divided into a control channel for transmitting control information and a traffic channel for transmitting user information according to the type of information to be transmitted. The MAC may have a function of multiplexing MAC SDUs belonging to one or more different logical channels and providing them to the PHY. Also, the MAC may have a function of demultiplexing the MAC PDUs provided from the PHY and providing them to the upper layer via the logical channels to which each MAC SDU belongs. Also, the MAC may have a function of performing error correction through HARQ (Hybrid Automatic Repeat reQuest). Also, the MAC may have a function of reporting scheduling information. The MAC may have a function of performing priority processing between terminal devices using dynamic scheduling. Also, the MAC may have a function of performing priority processing between logical channels within one terminal device. The MAC may have a function of performing priority processing on overlapping resources within one terminal device. ​​​​​​This is acceptable. The E-UTRA MAC may have a function to identify Multimedia Broadcast Multicast Services (MBMS). Likewise, the NR MAC may have a function to identify Multicast Broadcast Service (MBS). The MAC may have a function to select a transport format. The MAC may have functions such as discontinuous reception (DRX) and / or discontinuous transmission (DTX), a function to execute a random access (RA) procedure, a power headroom report (PHR) function to notify information on transmit power, a buffer status report (BSR) function to notify information on the data amount in a transmit buffer, etc. The NR MAC may have a bandwidth adaptation (BA) function. Also, the MAC PDU format used in E-UTRA MAC and the MAC PDU format used in NR MAC may be different. Further, the MAC PDU may include a MAC control element (MAC CE), which is an element for control in the MAC. In addition, on the PC5 interface, the MAC sublayer may additionally provide services and functions such as radio resource selection to select radio resources for sidelink transmission, filtering of packets received in sidelink communication, priority processing between the uplink and sidelink, reporting of sidelink channel state information (Sidelink CSI), etc.

[0046]

[0047] The logical channel for sidelink (SL) used in E-UTRA and / or NR, and the mapping between the logical channel for sidelink and the transport channel will be described.

[0048] SBCCH (Sidelink Broadcast Control Channel) may be a logical channel for sidelink for notifying sidelink system information from one terminal device to one or more terminal devices. Also, SBCCH may be mapped to SL-BCH, which is a sidelink transport channel. pping may be performed.

[0049] SCCH (Sidelink Control Channel) may be a logical channel for sidelink for transmitting control information such as PC5-RRC messages and PC5-S messages from one terminal device to one or more terminal devices. Also, SCCH may be mapped to SL-SCH, which is a sidelink transport channel.

[0050] STCH (Sidelink Traffic Control Channel) may be a logical channel for sidelink for transmitting user information from one terminal device to one or more terminal devices. Also, STCH may be mapped to SL-SCH, which is a sidelink transport channel.

[0051] An example of the function of RLC will be described. RLC may also be called the RLC sublayer. E-UTRA RLC may have a function of segmenting and / or concatenating the data provided by the upper-layer PDCP and providing it to the lower layer. E-UTRA RLC may perform reassembly and reordering on the data provided by the lower layer. It may have a function of performing re-ordering and providing it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from PDCP of the upper layer. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a function of retransmitting data and / or a retransmission request function (Automatic Repeat reQuest: ARQ). Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, which is sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a function of discarding data. RLC may have three modes: transparent mode (TM: Transparent Mode), unacknowledged mode (UM: Unacknowledged Mode), and acknowledged mode (AM: Acknowledged Mode). In TM, the data received from the upper layer is not segmented, and the addition of the RLC header may not be performed. TM RLC e It may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from PDCP of the upper layer. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a function of retransmitting data and / or a retransmission request function (Automatic Repeat reQuest: ARQ). Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, which is sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a function of discarding data. RLC may have three modes: transparent mode (TM: Transparent Mode), unacknowledged mode (UM: Unacknowledged Mode), and acknowledged mode (AM: Acknowledged Mode). In TM, the data received from the upper layer is not segmented, and the addition of the RLC header may not be performed. It may have a function of retransmitting data and / or a retransmission request function (Automatic Repeat reQuest: ARQ). Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, which is sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a function of discarding data. RLC may have three modes: transparent mode (TM: Transparent Mode), unacknowledged mode (UM: Unacknowledged Mode), and acknowledged mode (AM: Acknowledged Mode). In TM, the data received from the upper layer is not segmented, and the addition of the RLC header may not be performed. It may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, which is sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a function of discarding data. RLC may have three modes: transparent mode (TM: Transparent Mode), unacknowledged mode (UM: Unacknowledged Mode), and acknowledged mode (AM: Acknowledged Mode). In TM, the data received from the upper layer is not segmented, and the addition of the RLC header may not be performed. The status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a function of discarding data. RLC may have three modes: transparent mode (TM: Transparent Mode), unacknowledged mode (UM: Unacknowledged Mode), and acknowledged mode (AM: Acknowledged Mode). In TM, the data received from the upper layer is not segmented, and the addition of the RLC header may not be performed. It may have a function of detecting data duplication. Also, RLC may have a function of discarding data. RLC may have three modes: transparent mode (TM: Transparent Mode), unacknowledged mode (UM: Unacknowledged Mode), and acknowledged mode (AM: Acknowledged Mode). In TM, the data received from the upper layer is not segmented, and the addition of the RLC header may not be performed. In TM, the data received from the upper layer is not segmented, and the addition of the RLC header may not be performed. The entity is a uni - directional entity and may be configured as a transmitting TM RLC entity or a receiving TM RLC entity. In UM, it performs segmentation and / or concatenation of data received from the upper layer, addition of RLC headers, etc., but may not perform re - transmission control of data. The UM RLC entity may be a uni - directional entity or a bi - directional entity. When the UM RLC entity is a uni - directional entity, the UM RLC entity may be configured as a transmitting UM RLC entity or a receiving UM RLC entity. When the UM RLC entity is a bi - directional entity, the UM RRC entity may be configured as a UM RLC entity composed of a transmitting side and a receiving side. AM may perform segmentation and / or concatenation of data received from the upper layer, addition of RLC headers, re - transmission control of data, etc. The AM RLC entity is a bi - directional entity and is configured as an AM RLC composed of a transmitting side and a receiving side and may be so configured. Note that the data provided to the lower layer by TM, and / or the data provided by the lower layer may be called a TMDPDU. Also, the data provided to the lower layer by UM, and / or the data provided by the lower layer may be called a UMDPDU. Also, the data provided to the lower layer by AM or the data provided by the lower layer may be called an AMD PDU. Used in E - UTRA RLC The RLC PDU format used by the RLC PDU format to be obtained may be different from the RLC PDU format used in NR RLC. In addition, the RLC PDU may include a data RLC PDU and a control RLC PDU. The data RLC PDU may be referred to as an RLC DATA PDU (RLC Data PDU, RLC data PDU). The control RLC PDU may be referred to as an RLC CONTROL PDU (RLC Control PDU, RLC control PDU, RLC control PDU). Note that The control RLC PDU used for transmitting the status report may be referred to as a status PDU (STATUS PDU). It may be called.

[0052] Note that in the sidelink, TM may be used for SBCCH, and only UM is used for groupcast transmission and broadcast transmission, and UM and AM can be used for unicast transmission. Also, in the sidelink, the UM in groupcast transmission and broadcast transmission supports only unidirectional transmission.

[0053] An example of the function of PDCP will be described. PDCP may be referred to as a PDCP sublayer. PDCP may have a function of maintaining a sequence number. PDCP may also have a header compression / decompression function for efficiently transmitting user data such as IP packets (IP Packets) and Ethernet frames in a radio section. The protocol used for header compression / decompression of IP packets may be referred to as a ROHC (Robust Header Compression) protocol. Also, the protocol used for header compression / decompression of an Ethernet frame header may be referred to as an EHC (Ethernet (registered trademark) ). ). It can be called the (Header Compression) protocol. Also, PDCP may have the function of encrypting / decrypting data. Also, PDCP may have the function of protecting data integrity / verifying data integrity. Also, PDCP may have the function of re-ordering. Also, PDCP may have the function of retransmitting PDCP SDUs. Also, PDCP may have the function of discarding data using a discard timer. Also, PDCP may have the function of duplication. Also, PDCP may have the function of discarding duplicate received data. The PDCP entity is a bidirectional entity and may be composed of a transmitting PDCP entity and a receiving PDCP entity. Also, the PDCP PDU format used in E-UTRA PDCP and the PDCP PDU format used in NR PDCP may be different. Also, the PDCP PDU may include a PDCP PDU for data and a PDCP PDU for control. The PDCP PDU for data may be called a PDCP DATA PDU (PDCP Data PDU, PDCP data PDU). Also, the PDCP PDU for control may be called a PDCP CONTROL PDU (PDCP Control PDU, PDCP control PDU, PDCP control PDU).

[0054] Note that in the sidelink, there are the following restrictions regarding the functions and services of PDCP. (1) Out-of-order delivery may be supported only for unicast transmission. be. (2) Duplication on the PC5 interface is not supported.

[0055] An example of the function of SDAP will be described. SDAP is the service data adaptation protocol layer (service data adaptation protocol layer). In the sidelink, SDAP is either a terminal device It may have a function of associating (mapping) the QoS flow of sidelink (PC5 QoS flow) sent to other terminal devices with the sidelink data radio bearer (SL-DRB). Also, SDAP may have a function of storing mapping rule information. Also, SDAP may have a function of marking the QoS flow identifier (QoS Flow ID: QFI) and the PC5 QoS flow identifier (PC5 QoS Flow ID: PQFI or PFI). Note that the SDAP PDU may include a data SDAP PDU and a control SDAP PDU. The data SDAP PDU may be called SDAP DATA PDU (SDAP Data PDU, SDAP data PDU). It may have a function of associating (mapping) the QoS flow of sidelink (PC5 QoS flow) sent to other terminal devices with the sidelink data radio bearer (SL-DRB). Also, SDAP may have a function of storing mapping rule information. Also, SDAP may have a function of marking the QoS flow identifier (QoS Flow ID: QFI) and the PC5 QoS flow identifier (PC5 QoS Flow ID: PQFI or PFI). Note that the SDAP PDU may include a data SDAP PDU and a control SDAP PDU. The data SDAP PDU may be called SDAP DATA PDU (SDAP Data PDU, SDAP data PDU). It may have a function of associating (mapping) the QoS flow of sidelink (PC5 QoS flow) sent to other terminal devices with the sidelink data radio bearer (SL-DRB). Also, SDAP may have a function of storing mapping rule information. Also, SDAP may have a function of marking the QoS flow identifier (QoS Flow ID: QFI) and the PC5 QoS flow identifier (PC5 QoS Flow ID: PQFI or PFI). Note that the SDAP PDU may include a data SDAP PDU and a control SDAP PDU. The data SDAP PDU may be called SDAP DATA PDU (SDAP Data PDU, SDAP data PDU). And the control SDAP PDU may be called SDAP CONTROL PDU (SDAP Control PDU, SDAP control rule PDU, SDAP control PDU). Note that in the sidelink, the SDAP entity of the terminal device may exist one for each destination for any of unicast transmission, group cast transmission, and broadcast transmission associated with the destination. Also, reflective QoS is not supported on the PC5 interface. And the control SDAP PDU may be called SDAP CONTROL PDU (SDAP Control PDU, SDAP control rule PDU, SDAP control PDU). Note that in the sidelink, the SDAP entity of the terminal device may exist one for each destination for any of unicast transmission, group cast transmission, and broadcast transmission associated with the destination. Also, reflective QoS is not supported on the PC5 interface. And the control SDAP PDU may be called SDAP CONTROL PDU (SDAP Control PDU, SDAP control rule PDU, SDAP control PDU). Note that in the sidelink, the SDAP entity of the terminal device may exist one for each destination for any of unicast transmission, group cast transmission, and broadcast transmission associated with the destination. Also, reflective QoS is not supported on the PC5 interface. And the control SDAP PDU may be called SDAP CONTROL PDU (SDAP Control PDU, SDAP control rule PDU, SDAP control PDU). Note that in the sidelink, the SDAP entity of the terminal device may exist one for each destination for any of unicast transmission, group cast transmission, and broadcast transmission associated with the destination. Also, reflective QoS is not supported on the PC5 interface.

[0056] An example of the function of RRC will be described. RRC is between peer UEs on the PC5 interface It may support services and functions such as the transfer of PC5-RRC messages, the maintenance and release of PC5-RRC connections between two UEs, and the detection of sidelink radio link failures for PC5-RRC connections. The PC5-RRC connection is a logical connection between two UEs corresponding to a pair of source L2ID and destination L2ID, and is considered to be established after the corresponding PC5 unicast link is established. Also, there is a one-to-one correspondence between the PC5-RRC connection and the PC5 unicast link. Also, a UE may have multiple PC5-RRC connections for one or more UEs for different pairs of source L2ID and destination L2ID. Individual PC5-RRC procedures and messages may be used by the UE to transfer UE capability and sidelink configuration to the peer UE. Also, both peer UEs may exchange their UE capabilities and sidelink configurations with each other using individual two-way procedures. If there is no interest in sidelink transmission, when a sidelink radio link failure is detected for the PC5-RRC connection, and when the layer 2 link release procedure is completed, the UE releases the PC5-RRC connection.

[0057] Terminal devices capable of sidelink communication may perform discovery. There may be Model A and Model B in discovery. Figure 4 describes the protocol stack in the discovery procedure. Model A may use a single discovery protocol message, and Model B may use two discovery protocol messages. The single discovery protocol message in Model A may be an Announcement message, and the discovery protocol messages in Model B may be Solicitation messages. It may be a message and a response message. Note that the announcement message, the invitation message, and the response message may be collectively referred to as discovery messages, and other named messages used in the discovery procedure may also be referred to as discovery messages. The following outlines the procedures for Model A and Model B in ProSe Direct Discovery.

[0058] In Model A, the UE that transmits the announcement message may be referred to as the Announcing UE, and the UE that monitors the announcement message may be referred to as the Monitoring UE. The announcement message may include information such as the type of discovery message, the ProSe Application Code or ProSe Restricted Code, and the security protection element, and may additionally include metadata information. The announcement message is transmitted using the Destination Layer-2 ID and the Source Layer-2 ID, and the Monitoring UE determines the Destination Layer-2 ID to receive the announcement message. Note that the Destination Layer-2 ID may be the Layer-2 identifier of the destination UE, and the Source Layer-2 ID may be the Layer-2 identifier of the source UE. The destination UE may simply be referred to as the destination.

[0059] In Model B, the UE that transmits the invitation message may be referred to as the discoverer UE. A UE that receives an invitation message and / or a UE that sends a response message to the discoverer UE may be referred to as a discoveree UE. The invitation message may include information such as the type of discovery message, ProSe Query Code, and security protection element. The invitation message is sent using the destination L2ID and source L2ID, and the discoveree UE determines the destination L2ID to receive the invitation message. Also, the discoveree UE that responds to the invitation message sends a response message. The response message may include information such as the type of discovery message, ProSe Response Code, and security protection element, and may additionally include metadata information. The response message is sent using the source L2ID, and the destination L2ID is set to the source L2ID of the received invitation message.

[0060] In discovery, there may be types other than ProSe Direct Discovery that discover other UEs for direct communication with other UEs, such as Group member Discovery that discovers one or more UEs for in-group communication using sidelink, and 5G ProSe UE-to-Network Relay Discovery that discovers candidate relay UEs for connecting to the network via a relay UE. Note that the above-mentioned discovery is an example of discovery provided by an application called ProSe. However, in addition to the above-mentioned types, there may be different types of discovery depending on the application or service that performs sidelink communication. Also, the information included in the discovery protocol message may vary depending on the type of discovery, and additional messages may be sent to send additional information.

[0061] FIG. 4 is a diagram of an example of a protocol configuration including the discovery protocol according to the present embodiment. It is as follows. As shown in FIG. 4, the protocol stack of the discovery plane including the discovery protocol may include a PHY (Physical layer) 200 which is a radio physical layer, a MAC (Medium Access Control) 202 which is a medium access control layer, a RLC (Radio Link Control) 204 which is a radio link control layer, a PDCP (Packet Data Convergence Protocol) 206 which is a packet data convergence protocol layer, and a Discovery 400 which is a discovery protocol layer. Discovery 400 may be a protocol used to process procedures related to discovery. Also, the interface between UEs performing discovery may be referred to as PC5-D. The protocol stack may be composed of a PHY (Physical layer) 200 which is a radio physical layer, a MAC (Medium Access Control) 202 which is a medium access control layer, a RLC (Radio Link Control) 204 which is a radio link control layer, a PDCP (Packet Data Convergence Protocol) 206 which is a packet data convergence protocol layer, and a Discovery 400 which is a discovery protocol layer. Discovery 400 may be a protocol used to process procedures related to discovery. Also, the interface between UEs performing discovery may be referred to as PC5-D. A plurality of resource pools for transmitting messages (discovery messages) used in procedures related to discovery may be set, or one or more resource pools dedicated to discovery may be set. When a resource pool dedicated to discovery is set, the UE uses the resource pool dedicated to discovery as the resource pool for transmitting discovery messages. When a resource pool dedicated to discovery is not set, the UE may use the resource pool for sidelink communication as the resource pool for transmitting discovery messages. Note that a plurality of resource pools for sidelink communication and resource pools dedicated to discovery may be set simultaneously. Each resource pool may be set by UE-specific signaling or may be set in advance.

[0062] A plurality of resource pools for transmitting messages (discovery messages) used in procedures related to discovery may be set, or one or more resource pools dedicated to discovery may be set. When a resource pool dedicated to discovery is set, the UE uses the resource pool dedicated to discovery as the resource pool for transmitting discovery messages. When a resource pool dedicated to discovery is not set, the UE may use the resource pool for sidelink communication as the resource pool for transmitting discovery messages. Note that a plurality of resource pools for sidelink communication and resource pools dedicated to discovery may be set simultaneously. Each resource pool may be set by UE-specific signaling or may be set in advance. It may be set in advance.

[0063] In each unicast PC5-RRC connection, a signaling radio bearer (SRB) for sidelink may be configured. The sidelink SRB used to send PC5-S messages before PC5-S security is established may be referred to as SL-SRB0. Also, the PC5-S security The sidelink SRB used to send PC5-S messages for establishing may be referred to as SL-SRB1. Also, after PC5-S security is established, the sidelink SRB used to send protected PC5-S messages may be referred to as SL-SRB2. Also, after PC5-S security is established, the sidelink SRB used to send protected PC5-RRC signaling may be referred to as SL-SRB3. Also, the sidelink SRB used to send and / or receive discovery messages in NR may be referred to as SL-SRB4. Note that PC5-RRC signaling may be RRC signaling between UEs transmitted and received on PC5. Note that PC5-RRC signaling may be referred to as PC5-RRC messages and the like.

[0064] Multi-path relay (or Multi-path relaying) will be described. Multi-path relay is a technology in which a terminal device communicates with a base station device using two paths: a direct path and an indirect path. The direct path may be a path through which the terminal device directly communicates with the base station device via the Uu interface. Also, the indirect path may be a path through which the terminal device communicates with the base station device via a relay terminal device. The interface between the terminal device and the relay terminal device may be the PC5 interface or a different interface. Multi-path In relay, two paths, a direct path and an indirect path The terminal device that is used to connect to the base station device may be referred to as a multi-path remote terminal device (MP Remote UE), and the relay terminal device that provides a connection to the base station for the multi-path remote terminal device may be referred to as a multi-path relay terminal device (MP Relay UE). Also, the relay terminal device may be a terminal device that plays the role of a U2N Relay UE. As an interface between the multi-path remote terminal device and the relay terminal device, when a PC5 interface is used the multi-path relay terminal device may be a terminal device that plays the role of an L2 U2N Relay UE, and the multi-path remote terminal device may be a terminal device that plays the role of an L2 U2N Remote UE. Also, as an interface between the multi-path remote terminal device and the relay terminal device, when a non-3GPP connection is used, the multi-path relay terminal device may be a terminal device that plays the role of an N3C (Non-3GPP Connection) Relay UE, and the multi path remote terminal device may be a terminal device that plays the role of an N3C Remote UE. In the following description, the multi-path remote terminal device may be referred to without distinguishing between an N3C Remote UE and an L2 U2N Remote UE, and the multi-path relay terminal device may be referred to without distinguishing between an N3C Relay UE and an L2 U2N Relay UE.

[0065] In multi-path relay, a bearer mapped to a direct path may be called a direct bearer, a bearer mapped to a non-direct path may be called an indirect bearer, or a bearer mapped to both a direct path and a non-direct path may be called a multi-path split bearer (MP (Multi-path) split bearer), or simply a split bearer.

[0066] ​In a multi-path split bearer, for a PDCP entity of a terminal device having two paths, namely a direct path and an indirect path, an RLC channel for the Uu interface and an RLC channel for the indirect path may be configured. Further, when the interface between the terminal device and the relay terminal device in the indirect path is the PC5 interface, the RLC channel for the indirect path may be an RLC channel for the PC5 interface. When PDCP duplication is configured for the multi-path split bearer and the PDCP duplication is activated, in the PDCP entity, the PDCP DATA PDU to be submitted to the lower layer is duplicated, and data may be submitted to both of the plurality of RLC channels configured for the PDCP entity. The multi-path split bearer may be referred to as a bearer for which the multi-path split bearer is configured. Further, the multi-path split bearer may be configured for either a data radio bearer or a signaling radio bearer. Also, when PDCP duplication is not configured for the bearer for which the split bearer is configured (or, although PDCP duplication is configured, it is not activated) and a preferred path is configured, the PDCP DATA PDU may be submitted to the primary RLC entity configured for the preferred path. When a split secondary RLC entity is configured and the amount of data submitted to the primary RLC entity and the split secondary RLC entity is equal to or greater than a threshold value, the PDCP DATA PDU may be submitted to either the primary RLC entity or the split secondary RLC entity. When the interface between the relay terminal device and the terminal device in the indirect path is the PC5 interface, the RLC channel for the indirect path may be an RLC channel for the PC5 interface. When PDCP duplication is configured for the multi-path split bearer and the PDCP duplication is activated, in the PDCP entity, the PDCP DATA PDU to be submitted to the lower layer is duplicated, and the PDCP entity duplicates the PDCP DATA PDU to be submitted to the lower layer and submits the data to both of the plurality of RLC channels configured for the PDCP entity. submits data to both of the plurality of RLC channels configured for the PDCP entity. The multi-path split bearer may be referred to as a bearer for which the multi-path split bearer is configured. Further, the multi-path split bearer may be configured for either a data radio bearer or a signaling radio bearer. Also, when PDCP duplication is not configured for the bearer for which the split bearer is configured (or, although PDCP duplication is configured, it is not activated) and a preferred path is configured, the PDCP DATA PDU may be submitted to the primary RLC entity configured for the preferred path. When a split secondary RLC entity is configured and the amount of data submitted to the primary RLC entity and the split secondary RLC entity is equal to or greater than a threshold value, the PDCP DATA PDU may be submitted to either the primary RLC entity or the split secondary RLC entity.

[0067] Here, the UE-to-Network (U2N) relay used in the communication in the indirect path will be described. The U2N relay may be a function that provides connectivity to the network for a remote terminal device (Remote UE). A remote terminal device that connects to the network using the U2N relay may be referred to as a U2N Remote UE. Also, a terminal device that provides network connectivity to the U2N Remote UE may be referred to as a U2N Relay UE, or simply a Relay UE. The U2N Relay UE may use the Uu interface for communication with the base station device, or may use the PC5 interface for communication with the U2N Remote UE. Also, there may be types of U2N relays such as Layer 2 (L2) U2N relays and Layer 3 (L3) U2N relays. A remote terminal device in the L2 U2N relay may be particularly referred to as an L2 U2N Remote UE, and a relay terminal device in the L2 U2N relay may be particularly referred to as an L2 U2N Relay UE. Also, in the L2 U2N relay, there may be a SRAP (SRAP layer) 600 that is a Sidelink Relay Adaptation Protocol (SRAP) layer. Note that SRAP600 may also be simply expressed as SRAP. It may be used, or the PC5 interface may be used for communication with the U2N Remote UE. Also, there may be types of U2N relays such as Layer 2 (L2) U2N relays and Layer 3 (L3) U2N relays. A remote terminal device in the L2 U2N relay may be particularly referred to as an L2 U2N Remote UE, and a relay terminal device in the L2 U2N relay may be particularly referred to as an L2 U2N Relay UE. Also, in the L2 U2N relay, there may be a SRAP (SRAP layer) 600 that is a Sidelink Relay Adaptation Protocol (SRAP) layer. Note that SRAP600 may also be simply expressed as SRAP. relay may be particularly referred to as an L2 U2N Relay UE. Also, in the L2 U2N relay, there may be a SRAP (SRAP layer) 600 that is a Sidelink Relay Adaptation Protocol (SRAP) layer. Note that SRAP600 may also be simply expressed as SRAP. In the relay, there may be a SRAP (SRAP layer) 600 that is a Sidelink Relay Adaptation Protocol (SRAP) layer. Note that SRAP600 may also be simply expressed as SRAP.

[0068] FIG. 6 is a diagram of an example of the protocol configuration of the control plane (C-plane) including the SRAP layer according to the present embodiment. Also, FIG. 7 is a diagram of an example of the protocol configuration of the user plane (U-plane) including the SRAP layer according to the present embodiment. As shown in FIGS. 6 and 7, the SRAP layer may be associated between the Remote UE and the Relay UE, and may also be associated between the Relay UE and the gNB102. Note that the gNB102 shown in FIGS. 6 and 7 may be an ng-eNB100. Also, the Remote UE or the Relay UE may be a UE122. UE, and may also be associated between the Relay UE and the gNB102. Note that the gNB102 shown in FIGS. 6 and 7 may be an ng-eNB100. Also, the Remote UE or the Relay UE may be a UE122. Note that the gNB102 shown in FIGS. 6 and 7 may be an ng-eNB100. Also, the Remote UE or the Relay UE may be a UE122.

[0069] Here, the SRAP layer will be described. The SRAP layer may be referred to as a SRAP sublayer, or simply as SRAP. The SRAP sublayer is for both the control plane and the user plane of both the PC5 interface and the Uu interface. It may exist above the RLC sublayer for the user plane. The SRAP sublayer on PC5 may be used for the purpose of bearer mapping. In the L2 U2N Relay UE, the SRAP sublayer may include one SRAP entity on the Uu interface and may include SRAP entities that are separately collocated on the PC5 interface. In the L2 U2N Remote UE, the SRAP sublayer may include only one SRAP entity on the PC5 interface. The SRAP entities associated between the Remote UE and the Relay UE via the PC5 interface may be specifically referred to as PC5-SRAP and the SRAP entities associated between the Relay UE and the gNB via Uu may be specifically referred to as Uu-SRAP. Also, when clarifying the interface name, for other entities as well as SRAP, it may be expressed in the form of (interface name)-(entity name) . Each SRAP entity may have a transmitting part and a receiving part. On the PC5 interface, the transmitting part of the SRAP entity of the L2 U2N Remote UE may be associated with the receiving part of the SRAP entity of the L2 U2N Relay UE, and the receiving part of the SRAP entity of the L2 U2N Remote UE may be associated with the transmitting part of the SRAP entity of the L2 U2N Relay UE. Also, on the Uu interface , the transmitting part of the SRAP entity of the L2 U2N Relay UE may be associated with the receiving part of the SRAP entity of the gNB102 and the receiving part of the SRAP entity of the L2 U2N Relay UE may be associated with the transmitting part of the SRAP entity of the gNB102.

[0070] Also, the SRAP entity has a function of transferring data, a function of determining the UE ID field and the bearer ID field of the SRAP header added to the data packet, and a function of determining the egress link It may have a function of determining the functional and egress RLC channel.

[0071] Also, in FIGS. 8 and 9, a PC5 Relay RLC channel may be set between the Remote UE and the Relay UE, and a Uu Relay RLC channel may be set between the Relay UE and the gNB102.

[0072] Next, the protocol configuration used between the base station device and the terminal device will be described. In the communication performed on the Uu interface between the terminal device and the base station device, that is, the communication in the direct path and the communication performed via the relay terminal device set in the non-direct path, the protocol used between the base station device and the terminal device may be used. Note that in the communication performed between the remote terminal device and the base station device via the relay terminal device, some protocols may not be associated between the remote terminal device and the base station device.

[0073] FIG. 7 is a diagram of an example of the NR protocol configuration according to this embodiment. The functions of each protocol described using FIG. 7 are some functions closely related to this embodiment, and it may have other functions. Note that in this embodiment, the uplink may be a link from the terminal device to the base station device And in this embodiment, the downlink may be a link from the base station device to the terminal device.

[0074] FIG. 7(A) is a diagram of the NR control plane (CP) protocol stack. As shown in FIG. 7(A), the NR CP protocol may be a protocol between the UE122 and the gNB102. That is, the NR CP protocol is , it may be a protocol terminated at the gNB102 on the network side. As shown in FIG. 7(A), the NR control plane protocol stack may include a Physical layer (PHY) 700 which is a radio physical layer, a Medium Access Control (MAC) 702 which is a medium access control layer, a Radio Link Control (RLC) 704 which is a radio link control layer, a Packet Data Convergence Protocol (PDCP) 706 which is a packet data convergence protocol layer, and a Radio Resource Control (RRC) 708 which is a radio resource control layer. Also, FIG. 7(B) is a diagram of the NR user plane (UP) protocol stack. As shown in FIG. 7(B), the NR UP protocol may be a protocol between the UE122 and the gNB102. That is, the NR UP protocol may be a protocol terminated at the gNB102 on the network side. As shown in FIG. 7(B), the NR user plane protocol stack may include a PHY 700 which is a radio physical layer, a MAC 702 which is a medium access control layer, an RLC 704 which is a radio link control layer, a PDCP 706 which is a packet data convergence protocol layer, and a Service Data Adaptation Protocol (SDAP) 710 which is a service data adaptation protocol layer. It may be composed of a Packet Data Convergence Protocol (PDCP) 706 and a Radio Resource Control (RRC) 708 which is a radio resource control layer. Also, FIG. 7(B) is a diagram of the NR user plane (UP) protocol stack. As shown in FIG. 7(B), the NR UP protocol may be a protocol between the UE122 and the gNB102. That is, the NR UP protocol may be a protocol terminated at the gNB102 on the network side. As shown in FIG. 7(B), the NR user plane protocol stack may include a PHY 700 which is a radio physical layer, a MAC 702 which is a medium access control layer, an RLC 704 which is a radio link control layer, a PDCP 706 which is a packet data convergence protocol layer, and a Service Data Adaptation Protocol (SDAP) 710 which is a service data adaptation protocol layer. It may be composed of the SDAP 710 which is a service data adaptation protocol layer.

[0075] Note that the Access Stratum (AS) layer may be a layer terminated between the UE122 and the gNB102. That is the AS layer may be a layer including some or all of the PHY 700, MAC 702, RLC 704, PDCP 706, and RRC 708. Also, the gNB102 may be an ng-eNB100. Also, only the NR protocol has been shown, but the E-UTRA protocol may also be used. In the E-UTRA protocol, SDAP710 may not exist, and the E-UTRA protocol may have functions partially different from the NR protocol.

[0076] In this embodiment, hereinafter, without distinguishing between the E-UTRA protocol and the NR protocol, the terms PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), and RRC (RRC layer) may be used. In this case, PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), and RRC (RRC layer) may be the PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), and RRC (RRC layer) of the E-UTRA protocol respectively, or may be the PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), and RRC (RRC layer) of the NR protocol. Also, SDAP (SDAP layer) may be the SDAP (SDAP layer) of the NR protocol.

[0077] Also, in this embodiment, when distinguishing between the E-UTRA protocol and the NR protocol hereinafter, PHY500, MAC502, RLC504, PDCP506, and RRC508 are respectively referred to as E-UTRA PHY or LTE PHY, E-UTRA MAC or LTE MAC, E-UTRA RLC or LTE RLC, E-UTRA PDCP or LTE PDCP, and E-UTRA RRC or LTE RRC. Also, PHY500, MAC502, RLC504, PDCP506, and RRC508 may be described as E-UTRA PHY or LTE PHY, E-UTRA MAC or LTE MAC, E-UTRA RLC or LTE RLC, E-UTRA PDCP or LTE PDCP, and E-UTRA RRC or LTE RRC, etc. Also, when distinguishing between the E-UTRA protocol and the NR protocol When doing so, PHY500, MAC502, RLC504, PDCP506, and RRC508 may also be referred to as NR PHY, NR MAC, NR RLC, NR RLC, and NR RRC, respectively. Also, PHY500, MAC502, RLC504, PDCP506, and RRC508 may sometimes be described as NR PHY, NR MAC, NR RLC, NR PDCP, NR RRC, etc., respectively.

[0078] Describe the entities in the AS layer of E-UTRA and / or NR. Physical An entity having some or all of the functions of the layer may be called a PHY entity. An entity having some or all of the functions of the MAC layer may be called a MAC entity . An entity having some or all of the functions of the RLC layer may be called an RLC entity. An entity having some or all of the functions of the PDCP layer may be called a PDCP entity. An entity having some or all of the functions of the SDAP layer may be called an SDAP entity. An entity having some or all of the functions of the RRC layer may be called an RRC entity. The PHY entity, MAC entity, RLC entity, PDCP entity ity, SDAP entity, and RRC entity may be referred to as PHY, MAC, RLC, PDCP, SDAP, and RRC, respectively. That is, they may be equivalently named.

[0079] Note that the data provided by the lower layer to MAC, RLC, PDCP, SDAP, and / or the data provided by the lower layer to MAC, RLC , PDCP, SDAP may be called MAC PDU (Protocol Data Unit), RLC PDU, PDCP PDU, and SDAP PDU, respectively. Also, the data provided by the upper layer to MAC, RLC, PDCP, SDAP, and / or the data provided by MAC, RLC, PDCP, SDAP to the upper layer The data can be referred to as MAC SDU (Service Data Unit), RLC SDU, PDCP SDU, and SDAP SDU respectively. Also, the segmented RLC SDU can be referred to as an RLC SDU segment.

[0080] Here, the base station device and the terminal device exchange signals in the upper layer (higher layer). The higher layer may also be referred to as the upper layer and can be used interchangeably. For example, the base station device and the terminal device may exchange RRC messages (also referred to as RRC messages and RRC signalling) in the Radio Resource Control (RRC) layer. Also, the base station device and the terminal device may exchange MAC control elements in the MAC (Medium Access Control) layer. Also, the RRC layer of the terminal device acquires system information notified from the base station device. Here, the RRC message, system information, and / or the MAC control element may also be referred to as an upper layer signal (higher layer signalling) or an upper layer parameter (higher layer parameter). Each parameter included in the upper layer signal received by the terminal device may also be referred to as an upper layer parameter. For example, in the processing of the PHY layer, the upper layer means the upper layer as seen from the PHY layer, and may mean one or more of the MAC layer, RRC layer, RLC layer, PDCP layer, NAS (Non-Access Stratum) layer, etc. For example, in the processing of the MAC layer, the upper layer may mean one or more of the RRC layer, RLC layer, PDCP layer, NAS layer, etc. For example, the base station device and the terminal device may exchange RRC messages (also referred to as RRC messages and RRC signalling) in the Radio Resource Control (RRC) layer. Also, the base station device and the terminal device may exchange MAC control elements in the MAC (Medium Access Control) layer. Also, the RRC layer of the terminal device acquires system information notified from the base station device. Here, the RRC message, system information, and / or the MAC control element may also be referred to as an upper layer signal (higher layer signalling) or an upper layer parameter (higher layer parameter). Each parameter included in the upper layer signal received by the terminal device may also be referred to as an upper layer parameter. For example, in the processing of the PHY layer, the upper layer means the upper layer as seen from the PHY layer, and may mean one or more of the MAC layer, RRC layer, RLC layer, PDCP layer, NAS (Non-Access Stratum) layer, etc. For example, in the processing of the MAC layer, the upper layer may mean one or more of the RRC layer, RLC layer, PDCP layer, NAS layer, etc. signaling) or an upper layer parameter (higher layer parameter). Each parameter included in the upper layer signal received by the terminal device may also be referred to as an upper layer parameter. For example, in the processing of the PHY layer, the upper layer means the upper layer as seen from the PHY layer, and may mean one or more of the MAC layer, RRC layer, RLC layer, PDCP layer, NAS (Non-Access Stratum) layer, etc. For example, in the processing of the MAC layer, the upper layer may mean one or more of the RRC layer, RLC layer, PDCP layer, NAS layer, etc. signaling) or an upper layer parameter (higher layer parameter). Each parameter included in the upper layer signal received by the terminal device may also be referred to as an upper layer parameter. For example, in the processing of the PHY layer, the upper layer means the upper layer as seen from the PHY layer, and may mean one or more of the MAC layer, RRC layer, RLC layer, PDCP layer, NAS (Non-Access Stratum) layer, etc. For example, in the processing of the MAC layer, the upper layer may mean one or more of the RRC layer, RLC layer, PDCP layer, NAS layer, etc.

[0081] Hereinafter, "A is provided by the upper layer" or "A is provided by the upper layer" The meaning of "(provided)" may be that the upper layer (mainly the RRC layer, MAC layer, etc.) of the terminal device receives A from the base station device, and the received A is provided (provided) from the upper layer of the terminal device to the physical layer of the terminal device. For example, in the terminal device, "the upper layer parameter is provided" may mean that the upper layer signal is received from the base station device, and the upper layer parameter included in the received upper layer signal is provided from the upper layer of the terminal device to the physical layer of the terminal device. That the upper layer parameter is set in the terminal device may also mean that the upper layer parameter is provided (provided) to the terminal device. For example, that the upper layer parameter is set in the terminal device may mean that the terminal device receives the upper layer signal from the base station device and sets the received upper layer parameter in the upper layer. However, that the upper layer parameter is set in the terminal device may also include setting the default parameter that has been previously provided to the upper layer of the terminal device. When explaining that the terminal device transmits an RRC message to the base station device, the expression of submitting a message from the RRC entity of the terminal device to the lower layer (lower layer) may be used. In the terminal device, submitting a message from the RRC entity to the "lower layer" may mean submitting the message to the PDCP layer. In the terminal device, submitting a message from the RRC layer to the "lower layer" may mean that since the RRC message is transmitted using the SRB (SRB0, SRB1, SRB2, SRB3, etc.), it is submitted to the PDCP entity corresponding to each SRB. When the RRC entity of the terminal device receives an indication from the lower layer, the lower layer may mean one or more of the PHY layer, MAC layer, RLC layer, PDCP layer, etc. An example of the function of the PHY will be described. The PHY of the terminal device receives the downlink from the PHY of the base station device. When explaining that the terminal device transmits an RRC message to the base station device, the expression of submitting a message from the RRC entity of the terminal device to the lower layer (lower layer) may be used. In the terminal device, submitting a message from the RRC entity to the "lower layer" may mean submitting the message to the PDCP layer. In the terminal device, submitting a message from the RRC layer to the "lower layer" may mean that since the RRC message is transmitted using the SRB (SRB0, SRB1, SRB2, SRB3, etc.), it is submitted to the PDCP entity corresponding to each SRB. When the RRC entity of the terminal device receives an indication from the lower layer, the lower layer may mean one or more of the PHY layer, MAC layer, RLC layer, PDCP layer, etc. entity corresponding to each SRB. When the RRC entity of the terminal device receives an indication from the lower layer, the lower layer may mean one or more of the PHY layer, MAC layer, RLC layer, PDCP layer, etc. When the RRC entity of the terminal device receives an indication from the lower layer, the lower layer may mean one or more of the PHY layer, MAC layer, RLC layer, PDCP layer, etc. When the RRC entity of the terminal device receives an indication from the lower layer, the lower layer may mean one or more of the PHY layer, MAC layer, RLC layer, PDCP layer, etc.

[0082] from the PHY of the base station device. Receive data transmitted via a downlink (DL) physical channel and may have a function. The PHY of the terminal device may have a function of transmitting data to the PHY of the base station device via an uplink (UL) physical channel. The PHY may be connected to the upper MAC via a transport channel. The PHY may deliver data to the MAC via a transport channel. Also, the PHY may be provided with data from the MAC via a transport channel. In the PHY, an RNTI (Radio Network Temporary Identifier) may be used to identify various control information.

[0083] Here, the physical channel will be described. The physical channels used for wireless communication between the terminal device and the base station device may include the following physical channels.

[0084] PBCH (Physical Broadcast Channel) PDCCH (Physical Downlink Control Channel) PDSCH (Physical Downlink Shared Channel) PUCCH (Physical Uplink Control Channel) PUSCH (Physical Uplink Shared Channel) PRACH (Physical Random Access Channel)

[0085] The PBCH may be used to notify the system information required by the terminal device.

[0086] ​​ Also, in NR, the PBCH may be used to notify a time index (SSB-Index) within a period of a Synchronization Signal Block (SSB).

[0087] The PDCCH may be used to transmit (or carry) downlink control information (DCI) in downlink wireless communication (wireless communication from a base station device to a terminal device). Here, one or more DCIs (which may also be referred to as DCI formats) may be defined for the transmission of downlink control information. That is, a field for downlink control information may be defined as DCI and mapped to information bits. The PDCCH may be transmitted in a PDCCH candidate. The terminal device may monitor a set of PDCCH candidates in a serving cell. Monitoring a set of PDCCH candidates may mean attempting to decode the PDCCH according to a certain DCI format. Also, the terminal device may monitor PDCCH candidates in one or more configured monitoring occasions within a configured control resource set (CORESET) set by a search space configuration. The DCI format may also be used for scheduling of the PUSCH in a serving cell. The PUSCH may be used for transmission of user data, transmission of an RRC message described later, and the like. By using two search space sets explicitly linked by a configuration provided by a higher layer (RRC layer), PDCCH repetition

[0088] ​​​may be operated. Also, two linked search space sets may be associated with a corresponding CORESET. For PDCCH repetition, the two linked search space sets may be configured in the terminal device with the same number of PDCCH candidates. Two PDCCH candidates existing in two linked search space sets may be linked by the same candidate index. When PDCCH repetition is scheduled in the terminal device, inter-slot repetition may be permitted, and each repetition may have the same number of control channel elements (CCEs), coded bits, and the same DCI payload. PUCCH may be used to transmit uplink control information (UCI) in uplink wireless communication (wireless communication from the terminal device to the base station device). Here, the uplink control information may include channel state information (CSI) used to indicate the state of the downlink channel. Also, the uplink control information may include a scheduling request (SR) used to request UL-SCH (Uplink Shared CHannel) resources. Also, the uplink control information may include HARQ-ACK (Hybrid Automatic Repeat reQuest ACKnowledgement).

[0089]

[0090] The PDSCH may be used for transmitting downlink data (DL-SCH: Downlink Shared Channel) from the MAC layer. In the case of downlink, the PDSCH may also be used for transmitting system information (SI) or random access response (RAR).

[0091] The PUSCH may be used for transmitting uplink data (UL-SCH: Uplink Shared Channel) from the MAC layer or for transmitting HARQ-ACK and / or CSI together with the uplink data. The PUSCH may also be used for transmitting only CSI or only HARQ-ACK and CSI. That is, the PUSCH may be used for transmitting only UCI. Also, the PDSCH or PUSCH may be used for transmitting RRC messages and MAC CE described later. Here, in the PDSCH, the RRC message transmitted from the base station device may be common signaling for a plurality of terminal devices within the cell. Also, the RRC message transmitted from the base station device may be dedicated signaling for a certain terminal device. That is, UE-specific information may be transmitted using dedicated signaling for a certain terminal device. Also, the PUSCH may be used for transmitting the UE capability in the uplink. The PRACH may be used for transmitting a random access preamble. The PRACH is used in the initial connection establishment procedure, handover procedure, connection re-establishment procedure, uplink

[0092] ​​​​For synchronizing (timing adjustment) for link transmission and indicating a request for UL-SCH resources It may be used.

[0093] An example of the MAC function will be described. The MAC may be referred to as the MAC sublayer. The MAC may have a function of mapping various logical channels to corresponding transport channels. The logical channels may be identified by logical channel identifiers (Logical Channel Identity, or Logical Channel ID). The MAC may be connected to the upper RLC via a logical channel. The logical channels may be divided into a control channel for transmitting control information and a traffic channel for transmitting user information according to the type of information to be transmitted. Also, the logical channels may be divided into an uplink logical channel and a downlink logical channel. The MAC may have a function of multiplexing MAC SDUs belonging to one or more different logical channels and providing them to the PHY. Also, the MAC may have a function of demultiplexing the MAC PDUs provided from the PHY and providing them to the upper layer via the logical channels to which each MAC SDU belongs. Also, the MAC may have a function of performing error correction through HARQ (Hybrid Automatic Repeat reQuest). Also, the MAC may have a function of reporting scheduling information It may have a function of performing priority processing between terminal devices using dynamic scheduling It may have a function of performing priority processing between logical channels within one terminal device It may have a function of performing priority processing of overlapping resources within one terminal device E-UTRA MAC identifies Multimedia Broadcast Multicast Services (MBMS) It may have the functions to perform. Also, the NR MAC may have the function to identify the Multicast Broadcast Service (MBS). The MAC may have the function to select a transport format. The MAC may have the functions to perform discontinuous reception (DRX) and / or discontinuous transmission (DTX), execute the random access (RA) procedure, notify the information of the transmit power headroom (Power Headroom Report: PHR), notify the data volume information of the transmit buffer (Buffer Status Report: BSR), etc. The NR MAC may have the bandwidth adaptation (BA) function. Also, the MAC PDU format used in E-UTRA MAC and the MAC PDU format used in NR MAC may be different. Further, the MAC PDU may include a MAC control element (MAC CE), which is an element for performing control in the MAC. It may have. Explain the logical channels for the uplink (UL) and / or downlink (DL) used in E-UTRA and / or NR.

[0094] The BCCH (Broadcast Control Channel) may be a downlink logical channel for broadcasting control information such as system information (SI).

[0095] The PCCH (Paging Control Channel) may be a downlink logical channel for carrying paging messages.

[0096]

[0097] The CCCH (Common Control Channel) may be a logical channel for transmitting control information between a terminal device and a base station device. The CCCH may be used when the terminal device does not have an RRC connection. Also, the CCCH may be used between the base station device and a plurality of terminal devices.

[0098] The DCCH (Dedicated Control Channel) may be a logical channel for transmitting dedicated control information in a one-to-one (point-to-point) and bi-directional manner between a terminal device and a base station device. The dedicated control information may be control information dedicated to each terminal device. The DCCH may be used when the terminal device has an RRC connection.

[0099] The DTCH (Dedicated Traffic Channel) may be a logical channel for transmitting user data in a one-to-one (point-to-point) manner between a terminal device and a base station device. The DTCH may be a logical channel for transmitting dedicated user data. The dedicated user data may be user data dedicated to each terminal device. The DTCH may exist on both the uplink and the downlink.

[0100] The mapping between the logical channel and the transport channel for the uplink in E-UTRA and / or NR will be described.

[0101] The CCCH may be mapped to the UL-SCH (Uplink Shared Channel), which is an uplink transport channel.

[0102] The DCCH may be mapped to the UL-SCH (Uplink Shared Channel), which is an uplink transport channel. ​

[0103] DTCH may be mapped to the UL-SCH (Uplink Shared Channel), which is an uplink transport channel. It may be mapped to.

[0104] Describe the mapping between the logical channel and the transport channel for the downlink in E-UTRA and / or NR. It will be described.

[0105] BCCH may be mapped to the BCH (Broadcast Channel), which is a downlink transport channel, and / or or the DL-SCH (Downlink Shared Channel).

[0106] PCCH may be mapped to the PCH (Paging Channel), which is a downlink transport channel. It may be mapped to.

[0107] CCCH may be mapped to the DL-SCH (Downlink Shared Channel), which is a downlink transport channel. It may be mapped to.

[0108] DCCH may be mapped to the DL-SCH (Downlink Shared Channel), which is a downlink transport channel. It may be mapped to.

[0109] DTCH may be mapped to the DL-SCH (Downlink Shared Channel), which is a downlink transport channel. It may be mapped to.

[0110] An example of the RLC function will be described. RLC may also be referred to as the RLC sublayer. E-UTRA RLC may have a function of segmenting and / or concatenating the data provided from the upper layer PDCP and providing it to the lower layer. E-UTRA RLC may have a function of performing reassembly and re-ordering on the data provided from the lower layer and providing it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from the upper layer PDCP. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a data retransmission function and / or an automatic repeat request (ARQ) function. Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e ring (re-ordering) and provide it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from the upper layer PDCP. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a data retransmission function and / or an automatic repeat request (ARQ) function. Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e ring (re-ordering) and provide it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from the upper layer PDCP. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a data retransmission function and / or an automatic repeat request (ARQ) function. Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e peat reQuest: ARQ). Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e ring (re-ordering) and provide it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from the upper layer PDCP. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a data retransmission function and / or an automatic repeat request (ARQ) function. Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e ring (re-ordering) and provide it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from the upper layer PDCP. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a data retransmission function and / or an automatic repeat request (ARQ) function. Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e ring (re-ordering) and provide it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from the upper layer PDCP. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a data retransmission function and / or an automatic repeat request (ARQ) function. Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e ring (re-ordering) and provide it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from the upper layer PDCP. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a data retransmission function and / or an automatic repeat request (ARQ) function. Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e ring (re-ordering) and provide it to the upper layer. NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided from the upper layer PDCP. Also, NR RLC may have a function of segmenting the data provided from PDCP and providing it to the lower layer. Also, NR RLC may have a function of performing reassembly on the data provided from the lower layer and providing it to the upper layer. Also, RLC may have a data retransmission function and / or an automatic repeat request (ARQ) function. Also, RLC may have a function of performing error correction by ARQ. To perform ARQ, the control information indicating the data that needs to be retransmitted, sent from the receiving side of RLC to the transmitting side, may be referred to as a status report. Also, the status report transmission instruction sent from the transmitting side of RLC to the receiving side may be referred to as a poll. Also, RLC may have a function of detecting data duplication. Also, RLC may have a data discard function. RLC may have three modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). In TM, data received from the upper layer is not segmented, and addition of an RLC header may not be performed. TM RLC e The entity is a uni-directional entity and may be configured as a transmitting TM RLC entity or a receiving TM RLC entity. In UM, it performs segmentation and / or concatenation of data received from the upper layer, addition of RLC headers, etc., but may not perform retransmission control of data. The UM RLC entity may be a uni-directional entity or a bi-directional entity. If the UM RLC entity is a uni-directional entity, the UM RLC entity may be configured as a transmitting UM RLC entity or a receiving UM RLC entity. If the UM RLC entity is a bi-directional entity, the UM RRC entity may be configured as a UM RLC entity composed of a transmitting side and a receiving side. AM may perform segmentation and / or concatenation of data received from the upper layer, addition of RLC headers, retransmission control of data, etc. The AM RLC entity is a bi-directional entity and is configured as an AM RLC composed of a transmitting side and a receiving side and may be so configured. Note that the data provided to the lower layer in TM, and / or the data provided from the lower layer may be referred to as a TMD PDU. Also, the data provided to the lower layer in UM, and / or the data provided from the lower layer may be referred to as a UMD PDU. Also, the data provided to the lower layer in AM , or the data provided from the lower layer may be referred to as an AMD PDU. Used in E-UTRA RLC The RLC PDU format to be used may be different from the RLC PDU format used in NR RLC. Also, the RLC PDU may include a data RLC PDU and a control RLC PDU. The data RLC PDU may be referred to as an RLC DATA PDU (RLC Data PDU, RLC data PDU). Also, the control RLC PDU may be referred to as an RLC CONTROL PDU (RLC Control PDU, RLC control PDU, RLC control PDU).

[0111] An example of the functions of PDCP will be described. PDCP may be referred to as a PDCP sublayer. PDCP may have a function of maintaining sequence numbers. Also, PDCP may have a header compression / decompression function for efficiently transmitting user data such as IP packets (IP Packets) and Ethernet frames in a radio section. The protocol used for header compression / decompression of IP packets may be called the ROHC (Robust Header Compression) protocol. Also, the protocol used for header compression / decompression of Ethernet frame headers may be called the EHC (Ethernet (registered trademark) Header Compression) protocol. Also, PDCP may have a function of encrypting / decrypting data. Also, PDCP may have a function of protecting data integrity / verifying data integrity. Also, PDCP may have a re-ordering function. Also, PDCP may have a retransmission function for PDCP SDUs. Also, PDCP may have a function of discarding data using a discard timer. Also, PDCP may have a duplication function. 。 Also, PDCP may have a function of discarding duplicate received data. The PDCP entity is a bidirectional entity and may be composed of a transmitting PDCP entity and a receiving PDCP entity. Also, the PDCP PDU format used in E-UTRA PDCP and the PDCP PDU format used in NR PDCP may be different. Also, the PDCP PDU may include a data PDCP PDU and a control PDCP PDU. The data PDCP PDU may be referred to as a PDCP DATA PDU (PDCP Data PDU, PDCP data PDU). Also, the control PDCP PDU may be referred to as a PDCP CONTROL PDU (PDCP Control PDU, PDCP control PDU, PDCP control PDU).

[0112] An example of the SDAP function will be described. SDAP is a service data adaptation protocol layer (service data adaptation protocol layer). SDAP may have a function of associating (mapping) a downlink QoS flow sent from the 5GC to the terminal device via the base station device with a data radio bearer (DRB), and / or mapping an uplink QoS flow sent from the terminal device to the 5GC via the base station device with a DRB. Also, SDAP may have a function of storing mapping rule information. Also, SDAP may have a function of marking a QoS flow identifier (QoS Flow ID: QFI). Note that the SDAP PDU may include a data SDAP PDU and a control SDAP P DU. The data SDAP PDU may be referred to as an SDAP DATA PDU (SDAP Data PDU, SDAP data PDU) and the control SDAP PDU may be referred to as an SDAP CONTROL PDU (SDAP Control PDU, SDAP control rule PDU, SDAP control PDU). Note that there may be one SDAP entity for the PDU session in the terminal device.

[0113] An example of the RRC function will be described. RRC may have a notification (broadcast) function. RRC may have a call (paging) function from the 5GC. RRC may have a call (paging) function from gNB102 or ng-eNB100. Also, RRC may have an RRC connection management function. Also, RRC may have a radio bearer control function. Also, RRC may have a cell group control function. Also, RRC may have a mobility control function. Also, RRC may have a terminal device measurement reporting and terminal device measurement reporting control function. Also, RRC may have a QoS management function. Also, RRC may have a radio link failure detection and recovery function. RRC may use RRC messages to perform notification, paging, RRC connection management, radio bearer control, cell group control, mobility control, terminal device measurement reporting and terminal device measurement reporting control, QoS management, radio link loss detection and recovery, etc. Note that the RRC messages and parameters used in E-UTRA RRC may be different from the RRC messages and parameters used in NR RRC. Note that the RRC messages may include a plurality of information elements (IEs: Information Element) for performing the above-described control, etc. The RRC messages may be sent using the BCCH of the logical channel, or may be sent using the PCCH of the logical channel, or may be sent using the CCCH of the logical channel, or may be sent using the DCCH of the logical channel. Also, the RRC messages sent using the DCCH are referred to as dedicated RRC signaling, or RRC signaling.

[0114]

[0115] ​​The RRC messages sent using BCCH may include, for example, a Master Information Block (MIB), each type of System Information Block (SIB), or other RRC messages. The RRC messages sent using PCCH may include, for example, a paging message or other RRC messages.

[0116] The RRC messages sent in the uplink (UL) direction using CCCH may include, for example, an RRC Setup Request message, an RRC Resume Request message, an RRC Reestablishment Request message, an RRC System Info Request message, etc. Also, for example, an RRC Connection Request message, an RRC Connection Resume Request message, an RRC Connection Reestablishment Request message, etc. may be included. Further, other RRC messages may be included. The RRC messages sent in the downlink (DL) direction using CCCH may include, for example, an RRC Connection Reject message, an RRC Connection Setup message, an RRC Connection Reestablishment message, an RRC Connection Reestablishment Reject message, etc.

[0117] This is acceptable. Additionally, for example, it may include an RRC Reject message, an RRC Setup message, etc. Other RRC messages may also be included.

[0118] RRC signaling sent in the uplink (UL) direction using DCCH may include, for example, a Measurement Report message a RRC Connection Reconfiguration Complete message, a RRC Connection Setup Complete message, a RRC Connection Reestablishment Complete message, a Security Mode Complete message, a UE Capability Information message, etc. Additionally, for example, a Measurement Report message, a RRC Reconfiguration Complete message, a RRC Setup Complete message a RRC Reestablishment Complete message, a RRC Resume Complete message, a Security Mode Complete message, a UE Capability Information message, etc. may be included. Other RRC signaling may also be included. a RRC Setup Complete message, a RRC Reestablishment Complete message, a RRC Resume Complete message, a Security Mode Complete message, a UE Capability Information message, etc. may be included. Other RRC signaling may also be included. a RRC Setup Complete message, a RRC Reestablishment Complete message, a RRC Resume Complete message, a Security Mode Complete message, a UE Capability Information message, etc. may be included. Other RRC signaling may also be included.

[0119] RRC signaling sent in the downlink (DL) direction using DCCH may include, for example, an RRC Connection Reconfiguration message, an RRC Connection Release message, a Security Mode Command message, a UE Capability Enquiry message, etc. Also, for example, an RRC Reconfiguration message, an RRC Resume message, an RRC Release message, an RRC Reestablishment message, a Security Mode Command message, a UE Capability Enquiry message, etc. may be included. Other RRC signaling may also be included.

[0120] The functions of the aforementioned PHY, MAC, RLC, PDCP, SDAP, and RRC are just examples, and some or all of each function may not be implemented. Also, some or all of the functions of each layer may be included in other layers.

[0121] The radio bearer will be described. When the terminal device communicates with the base station device, a radio connection is established by establishing a radio bearer (RB: Radio Bearer) between the terminal device and the base station device. The radio bearer used for CP may be called a Signaling Radio Bearer (SRB). Also, the radio bearer used for UP may be called a Data Radio Bearer (DRB). Each radio bearer has a radio bearer identifier (Identity: ID). may be allocated. The radio bearer identifier for an SRB may be referred to as an SRB identifier (SRB Identity, or SRB ID). The radio bearer identifier for a DRB may be referred to as a DRB identifier (DRB Identity, or DRB ID). SRBs from SRB0 to SRB2 may be defined for E-UTRA, and other SRBs may be defined. SRBs from SRB0 to SRB3 may be defined for NR, and other SRBs may be defined. SRB0 may be an SRB for RRC messages that are transmitted and / or received using the CCCH of the logical channel. SRB1 may be an SRB for RRC signaling and for NAS signaling before the establishment of SRB2. The RRC signaling transmitted and / or received using SRB1 may include piggybacked NAS signaling. The DCCH of the logical channel may be used for all RRC signaling and NAS signaling transmitted and / or received using SRB1. SRB2 may be an SRB for NAS signaling and for RRC signaling including logged measurement information. The DCCH of the logical channel may be used for all RRC signaling and NAS signaling transmitted and / or received using SRB2. Also, SRB2 may have a lower priority than SRB1. SRB3 may be an SRB for transmitting and / or receiving specific RRC signaling when EN-DC, NGEN-DC, NR-DC, etc. are set in the terminal device. The DCCH of the logical channel may be used for all RRC signaling and NAS signaling transmitted and / or received using SRB3. Also, other SRBs may be defined for other purposes. The RRC signaling transmitted and / or received using SRB1 may include piggybacked NAS signaling. All RRC signaling and NAS signaling transmitted and / or received using SRB1 may use the DCCH of the logical channel. SRB2 may be an SRB for NAS signaling and for RRC signaling including logged measurement information. All RRC signaling and NAS signaling transmitted and / or received using SRB2 may use the DCCH of the logical channel. Also, SRB2 may have a lower priority than SRB1. SRB3 may be an SRB for transmitting and / or receiving specific RRC signaling when EN-DC, NGEN-DC, NR-DC, etc. are set in the terminal device and for receiving. All RRC signaling and NAS signaling transmitted and / or received using SRB3 may use the DCCH of the logical channel. Also, other SRBs may be defined for other purposes. It may be prepared. The DRB may be a radio bearer for user data. The DTCH of the logical channel may be used for the RRC signaling in which transmission and / or reception is performed using the DRB.

[0122] The radio bearers in the terminal device will be described. The radio bearers may include RLC bearers. The RLC bearer may be composed of one or two RLC entities and a logical channel. When there are two RLC entities in the RLC bearer, the RLC entities may be TM RLC entities and / or the transmitting RLC entity and the receiving RLC entity in the RLC entity in the unidirectional UM mode. The SRB0 may be composed of one RLC bearer. The RLC bearer of the SRB0 may be composed of a TM RLC entity and a logical channel. The SRB0 may always be established in the terminal device in all states (such as the RRC idle state, the RRC connected state, and the RRC inactive state). When the terminal device transitions from the RRC idle state to the RRC connected state, the SRB1 may be established and / or set to one in the terminal device by the RRC signaling received from the base station device. The SRB1 may be composed of one PDCP entity and one or more RLC bearers. The RLC bearer of the SRB1 may be composed of an AM RLC entity and a logical channel. The SRB2 may be established and / or set to one in the terminal device by the RRC signaling received from the base station device when the terminal device in the RRC connected state with AS security activated. The SRB2 may be composed of one PDCP entity and one or more RLC bearers. The RLC bearer of the SRB2 may be composed of an AM RLC entity and a logical channel. Note that the PDCP on the base station device side of the SRB1 and the SRB2 may be placed in the master node. The SRB3 is added when a secondary node is added in EN-DC, or NGEN-DC, or NR-DC, or The SRB2 may be established and / or set to one in the terminal device by the RRC signaling received from the base station device. The SRB2 may be composed of one PDCP entity and one or more RLC bearers. The RLC bearer of the SRB2 may be composed of an AM RLC entity and a logical channel. The PDCP on the base station device side of the SRB1 and the SRB2 may be placed in the master node. The SRB3 is added when a secondary node is added in EN-DC, or NGEN-DC, or NR-DC, or or when the secondary node is changed, one established and / or configured in the RRC connected state with AS security activated by the RRC signaling received by the terminal device from the base station device, one may be established and / or configured in the terminal device. SRB3 is a direct SRB between the terminal device and the secondary node and may be so. SRB3 may be composed of one PDCP entity and one or more RLC bearers and may be so. The RLC bearer of SRB3 may be composed of an AM RLC entity and a logical channel. The PDCP on the base station device side of SRB3 may be placed in the secondary node. The DRB may be established and / or configured in the terminal device by the RRC signaling received by the terminal device from the base station device in the RRC connected state with AS security activated. The DRB may be composed of one PDCP entity and one or more RLC bearers and may be so. The RLC bearer of the DRB may be composed of an AM or UM RLC entity and a logical channel. For the RLC bearer established and / or configured in the cell group composed of E-UTRA, the established and / or configured RLC entity may be E-UTRA RLC. Also, for the RLC bearer established and / or configured in the cell group composed of NR, the established and / or configured RLC entity may be NR RLC. When EN-DC is configured in the terminal device, the PDCP entity established and / or configured for the MN (Master Node) terminated MCG bearer may be either E-UTRA PDCP or NR PDCP

[0123] and may be so. When EN-DC is configured in the terminal device, the PDCP entity established and / or configured for the MN (Master Node) terminated MCG bearer may be either E-UTRA PDCP or NR PDCP. Also, when EN-DC is configured in the terminal device and may be so. The established and / or configured RLC entity for the RLC bearer established and / or configured in the cell group composed of E-UTRA may be E-UTRA RLC. Also, the established and / or configured RLC entity for the RLC bearer established and / or configured in the cell group composed of NR may be NR RLC. When EN-DC is configured in the terminal device, the PDCP entity established and / or configured for the MN (Master Node) terminated MCG bearer may be either E-UTRA PDCP or NR PDCP and may be so. Also, when EN-DC is configured in the terminal device If so, the PDCP established and / or configured for other bearer types of radio bearers, i.e., MN-terminated split bearers, MN-terminated SCG bearers, SN (Secondary Node)-terminated MCG bearers, SN-terminated split bearers, and SN-terminated SCG bearers, may be NR PDCP. Also, when NGEN-DC, or NE-DC, or NR-DC is configured for the UE, for all bearer types the PDCP entity established and / or configured for the radio bearers therein may be NR PDCP.

[0124] In NR, the DRB established and / or configured for the UE may be associated with one PDU session. For one PDU session in the UE, one SDAP entity may be established and / or configured. The SDAP entity, PDCP entity, RLC entity, and logical channel established and / or configured for the UE may be established and / or configured by the RRC signaling received by the UE from the base station device. The reference signal received power (RSRP: Reference Signal Received Power) measured in the sidelink may be, for example, the following RSRP. Also, the following RSRP may be referred to as SL-RSRP.

[0125] (a) PSBCH RSRP (b) PSSCH RSRP (c) PSCCH RSRP (d) PSCCH RSRP

[0126] PSBCH-RSRP (PSBCH RSRP) is the power contribution of the resource elements that transmit a plurality of demodulation reference signals (DMRS: Demodulation Reference Signal) associated with PSBCH. Reference Signal: DMRS) to transmit the resource elements of the power contribution ​It may be defined as the linear average of (power contributions). Also, PSSCH-RSRP (PSSCH RSRP) may be defined as the linear average of the power contributions of the resource elements of the antenna ports that transmit a plurality of DMRSs associated with the PSSCH. When there are multiple antenna ports, the RSRP values for each antenna port may be summed. PSCCH-RSRP (PSCCH RSRP) may be defined as the linear average of the power contributions of the resource elements that transmit a plurality of DMRSs associated with the PSCCH. Note that the DMRS may be used, for example, to demodulate signals of PSBCH, PSSCH, and PSCCH. Also, a terminal device that performs sidelink communication with another terminal device may measure the RSRP (SL-RSRP) of the sidelink communication using the PSSCH or PSCCH transmitted from the other terminal device. Also, the terminal device may measure the RSRP (SD-RSRP) of the discovery message using, for example, the power contributions of the resource elements that transmit the DMRS associated with the discovery message. It may be defined as the linear average of the power contributions of the resource elements that transmit a plurality of DMRSs associated therewith. Note that the DMRS may be used, for example, to demodulate signals of PSBCH, PSSCH, and PSCCH. In addition, a terminal device that performs sidelink communication with another terminal device may measure the RSRP (SL-RSRP) of the sidelink communication using the PSSCH or PSCCH transmitted from the other terminal device. In addition, the terminal device may measure the RSRP (SD-RSRP) of the discovery message using, for example, the power contributions of the resource elements that transmit the DMRS associated with the discovery message.

[0127] Also, in the measurement in the sidelink, in addition to the SL-RSRP, UE122 may measure the following quantities. (a) Sidelink received signal strength indicator (SL RSSI) (b) Sidelink channel Occupancy ratio (SL CR) (c) Sidelink channel busy ratio (SL CBR)

[0128] The SL RSSI may be defined as the linear average of the power ([W]) observed in the subchannels configured in the OFDM symbols of the slot configured for PSCCH and PSSCH starting from the second OFDM symbol. Also, the SL CR in slot n may be in slot [n-a] or It may be defined as the linear average of the power contributions of the resource elements that transmit a plurality of DMRSs associated therewith. Note that the DMRS may be used, for example, to demodulate signals of PSBCH, PSSCH, and PSCCH. The sum of the number of subchannels used for sidelink transmission between slot [n - 1] and the number of subchannels allocated between slot [n] and slot [n + b] may be defined as a value obtained by dividing the sum of the number of subchannels set from slot [n - a] to slot [n + b] by the sum of the number of subchannels set from slot [n - a] to slot [n + b]. Also the SL CBR at slot n may be defined as the ratio of subchannels in which the SL RSSI exceeds a threshold within the resource pool during the period set as the CBR measurement window (from slot [n - a] to slot [n - 1]).

[0129] The L2 U2N Remote UE may discover candidate L2 U2N Relay UEs, measure the RSRP of the candidate L2 U2N Relay UEs, and then report one or more candidate L2 U2N Relay UEs to the base station apparatus. Note that the L2 U2N Remote UE may, before reporting one or more candidate L2 U2N Relay UEs to the base station apparatus, determine whether the measured RSRP of the candidate L2 U2N Relay UEs meets the selection criteria for the L2 U2N relay. The L2 U2N Remote UE may report only candidate L2 U2N Relay UEs that meet the selection criteria and match the criteria of the upper layer to the base station apparatus. Also, when the L2 U2N Remote UE reports one or more candidate L2 U2N Relay UEs to the base station apparatus, the report to the base station apparatus may include the identification information of the candidate L2 U2N Relay UE, the identification information of the serving cell of the candidate L2 U2N Relay UE, and the measurement result. Note that the measurement result may use the RSRP (SD-RSRP) of the discovery message transmitted by the candidate L2 U2N Relay UE. The identification information may be an identifier (ID).

[0130] Also, the L2 U2N Remote UE having a serving L2 U2N Relay UE may include the s​​ The Serving L2 U2N Relay UE may use RSRP (SL-RSRP) measured in sidelink communication with the Serving L2 U2N Relay UE. If SL-RSRP is not available in the measurement results, SD-RSRP may be used. The Serving L2 U2N Relay UE may be an L2 U2N Relay UE that provides connectivity to the base station device to the L2 U2N Remote UE.

[0131] There are two resource allocation modes for NR sidelink communication, This is the mode in which the UE performs sidelink transmission using the scheduled resources. Mode 1 is a mode in which the UE automatically selects resources for sidelink transmission, and Mode 2 is a mode in which the UE automatically selects resources for sidelink transmission. In Mode 1, the UE must be RRC_CONNECTED, and in Mode 2, the UE can perform sidelink transmission regardless of the RRC state or whether it is inside or outside NG-RAN. Therefore, the UE automatically selects resources available for sidelink transmission from one or more resource pools configured before the sidelink transmission.

[0132] Here, the band portion (BWP) will be explained.

[0133] The BWP may be a part or all of the band of the serving cell. The BWP may also be called a carrier BWP. One or more BWPs may be set in the terminal device. A BWP is system information associated with a synchronization signal detected in the initial cell search. A BWP may be set by the information included in the initial cell search. A BWP may be a frequency bandwidth associated with a frequency. For example, it may be set by Dedicated RRC signaling. Also, downlink BWP (DL BWP) The downlink BWP (DL BWP) and the uplink BWP (UL BWP) may be set individually. Also, one or more uplink BWPs may be associated with one or more downlink BWPs. Further, the uplink BWP and the downlink BWP may be associated by a default association, or by RRC signaling (e.g., Dedicated RRC signaling), or by physical layer signaling (e.g., association by downlink control information (DCI) notified by a downlink control channel), or a combination thereof. Also, in the downlink BWP, a CORESET may be set. A BWP may be composed of a group of consecutive physical resource blocks (PRBs). Also, for a terminal device in the connected state, parameters of the BWP (one or

[0134] more BWPs) of each component carrier may be set. The parameters of the BWP of each component carrier include (A) the type of cyclic prefix, (B) the subcarrier spacing, (C) the frequency position of the BWP (e.g., the start position on the low-frequency side or the center frequency position of the BWP) (the frequency position may use, for example, an ARFCN, or an offset from a specific subcarrier of the serving cell may be used. Also, the unit of the offset may be in subcarrier units or in resource block units. Also, both the ARFCN and the offset may be set. ), (D) the bandwidth of the BWP (e.g., the number of PRBs), (E) resource setting information of control signals, (F) the center frequency position of the SS block (the frequency position may use, for example, an ARFCN, or an offset from a specific subcarrier of the serving cell may be used. Also, the unit of the offset may be in subcarrier units or in resource block units. Also, both the ARFCN and the o ffset may be set. ) ), (D) the bandwidth of the BWP (e.g., the number of PRBs), (E) resource setting information of control signals, (F) the center frequency position of the SS block (the frequency position may use, for example, an ARFCN, or an offset from a specific subcarrier of the serving cell may be used. Also, the unit of the offset may be in subcarrier units or in resource block units. Also, both the ARFCN and the offset may be set. ) ), (D) the bandwidth of the BWP (e.g., the number of PRBs), (E) resource setting information of control signals, (F) the center frequency position of the SS block (the frequency position may use, for example, an ARFCN, or an offset from a specific subcarrier of the serving cell may be used. Also, the unit of the offset may be in subcarrier units or in resource block units. Also, both the ARFCN and the o Both of the settings may be configured. Some or all of ) may be included. Also, the resource configuration information of the control signal may be included in the configuration of at least a part or all of the BWPs of the PCell and / or the PSCell.

[0135] Among one or more configured BWPs, the terminal device may perform transmission and reception in the Active BWP (active BWP). In one serving cell associated with the terminal device, one or more BWPs may be configured. In one serving cell associated with the terminal device, Among one or more BWPs configured for one serving cell associated with the terminal device, at a certain time, at most one uplink BWP and / or at most one downlink BWP may be set as the Active BWP. The Active BWP for the downlink is also referred to as the Active DL BWP. The Active BWP for the uplink is also referred to as the Active UL BWP. Also, among the one or more configured BWPs of the terminal device, a BWP that is not the Active BWP may be referred to as an Inactive BWP (inactive BWP). .

[0136] Next, the serving cell will be described. In a terminal device in the RRC_CONNECTED state where one serving cell is configured, the serving cell may be composed of one primary cell (PCell). Also, in a terminal device in the RRC_CONNECTED state where multiple serving cells are configured, the serving cell may be one or more special cells. In a terminal device in the RRC_CONNECTED state where multiple serving cells are configured, the serving cell may be one or more special It may mean a set of cells composed of a special cell (SpCell) and one or more secondary cells (SCells). The SpCell may support PUCCH transmission and contention-based random access (CBRA). The PCell may be the cell used in the RRC connection establishment procedure when a terminal device in the RRC idle state transitions to the RRC connected state. Also, the PCell may be the cell used in the RRC connection re-establishment procedure when the terminal device re-establishes the RRC connection. Also, the PCell may be the cell used in the random access procedure during handover and may be so. Also, the SpCell may be a cell used for purposes other than the above-mentioned purposes.

[0137] The fact that the group of serving cells set for the terminal device is composed of the SpCell and one or more SCells may be regarded as carrier aggregation (CA) being set for the terminal device. Also, for a terminal device with CA set, the cell that provides additional radio resources for the SpCell may also mean an SCell .

[0138] The cell group set for the terminal device from the base station device will be described. The cell group may be composed of one SpCell. Also, the cell group may be composed of one SpCell and one or more SCells. That is, the cell group may be one SpCell and, optionally, one or more SCells. Also, the cell group may be expressed as a set of cells.

[0139] Dual Connectivity (DC) refers to a technology that performs data communication using the radio resources of cell groups respectively configured by a first base station device (first node) and a second base station device (second node). This may be the case for DC or MR-DC described later. When DC or MR-DC is performed, a cell group may be added to the terminal device from the base station device. To perform DC, the first base station device may add the second base station device. The first base station device may be called the Master Node (MN). Also, the cell group configured by the master node may be called the Master Cell Group (MCG). The second base station device may be called the Secondary Node (SN). Also, the cell group configured by the secondary node may be called the Secondary Cell Group (SCG). Note that the master node and the secondary node may be configured within the same base station device.

[0140] Also, when DC is not set, the cell group set for the terminal device may be called the MCG. Also, when DC is not set, the SpCell set for the terminal device may be the PCell. Also, NR without DC set may be called NR Standalone.

[0141] UE122 may receive the setting of the special cell (SpCell) from gNB102. For example, the RRC reconfiguration (RRCReconfiguration) message may include a cell group setting (information element named CellGroupConfig), and the cell group setting may include the setting of the special cell (information element named spCellConfig). The information element named spCellConfigDedicated included in the information element named spCellConfig is the cell setting dedicated to the UE122 set by this SpCellConfig. ​It may be an information element indicating []. The information element named spCellConfigDedicated may be rephrased as SpCellConfigDedicated or dedicated configuration for the SpCell. Note that the spCellConfigDedicated information element named [] may include a parameter of the identifier of the BWP named the firstActiveDownlinkBWP-Id of the first active downlink BWP described below. Further, the configuration of the special cell may include reconfiguration with synchronization (information element named reconfigurationWithSync) The information element named spCellConfigCommon included in the information element named reconfigurationWithSync may be used to set the cell-specific parameters of the serving cell (i.e., the special cell) of the UE122. Note that in order to specify that a certain statement is an information element, the statement may be expressed with the addition of the phrase "IE". For example, the reconfiguration with synchronization IE may be included in the RRC reconfiguration message, and the UE122 that has received the RRC reconfiguration message may perform reconfiguration with synchronization (procedure) according to the RRC reconfiguration message.

[0142] Next, radio link monitoring (RLM) in Uu will be described.

[0143] In the RRC connected state, the terminal device may perform RLM in the Active BWP described below or the BWP designated as the BWP for performing radio link monitoring. RLM may be performed based on a reference signal (e.g., CRS in E-UTRA, SSB / CSI-RS in NR) and a signal quality threshold. The reference signal may include SSB. The signal quality threshold may be set by the network. Optionally, a predefined threshold value may be used. The SSB-based RLM may be performed based on the SSB associated with the initial DL BWP described below. The SSB-based RLM may be configured for the initial DL BWP and one or more DL BWPs including the SSB associated with the initial DL BWP. For other DL BWPs, CSI-RS-based RLM may be performed.

[0144] In RLM, the terminal device may declare or detect a Radio Link Failure (RLF) based on any of the following criteria (A) to (D): (A) The radio problem timer that starts based on in-sync and out-of-sync notified from the PHY has expired. (B) The timer that starts based on the measurement report of a specific measurement identifier being triggered while the radio problem timer is running has expired. (C) The random access procedure has failed. (D) An RLC failure has been detected.

[0145] A terminal device that has detected an RLF in the MCG may remain in the RRC connected state and start the re-establishment procedure by selecting the optimal cell. Also, when DC is configured, a terminal device that has declared an RLF may remain in the RRC connected state and notify the network of the RLF. Note that the terminal device may detect an RLF in the MCG based on any of the above criteria (A) to (D) being satisfied in the PCell (for example, in case of (A), the radio problem timer of the PCell has expired; in case of (C), the random access procedure has failed in the MCG's MAC).

[0146] The terminal device may be configured by the network via RRC signaling with reference signals used for RLM. For RRC signaling, RadioLinkMonitoringConfig may be used. The terminal device may perform RLM using one or more reference signals (referred to as RLM-RS) configured by the RadioLinkMonitoringConfig. Also, if no RLM-RS is specified for the terminal device, it may perform RLM using a default reference signal. The RadioLinkMonitoringConfig may be configured for the terminal device for each DL BWP. The RadioLinkMonitoringConfig may be configured for the DL BWP of the PCell and / or PSCell.

[0147] When the PHY of the terminal device meets the conditions for being in-sync, it may notify the upper layer (RRC layer) that it is in-sync. When the PHY of the terminal device meets the conditions for being out-of-sync, it may notify the upper layer (such as RRC) that it is out-of-sync.

[0148] The RadioLinkMonitoringConfig may include information indicating the purpose of monitoring and identifier information indicating the reference signal. For example, the purposes of monitoring may include the purpose of monitoring radio link failure, the purpose of monitoring beam failure, or both purposes. Also, for example, the identifier information indicating the reference signal may include information indicating the SSB-Index of the cell's SSB. Also, for example, the identifier information indicating the reference signal may include information indicating an identifier associated with a channel state information reference signal (CSI-RS) configured for the terminal device.

[0149] If no RLM-RS is provided for the terminal device and one or more (multiple) TCI states for PDCCH reception including one or more CSI-RS are provided, the terminal device may perform part or all of the following (A) to (B). ​ (A) When the activated TCI state for PDCCH reception includes only one reference signal, use the reference signal provided in the activated TCI state for radio link monitoring (B) When the activated TCI state for PDCCH reception includes two reference signals, expect that the QCL type of one reference signal is set to type D, and use the reference signal with the QCL type set to type D for radio link monitoring

[0150] If there are multiple DL BWPs described below configured for a serving cell, the terminal device may perform RLM using the reference signal corresponding to the RLM-RS in the Active DL BWP described below. Also, if there are multiple downlink BWPs described below configured for a serving cell and the RLM-RS is not provided for the Active DL BWP described below, the terminal device may perform RLM using the (multiple) reference signals provided in the activated TCI state for receiving PDCCH in the CORESET of that Active DL BWP The terminal device performing RLM may be rephrased as the PHY of the terminal device measuring the radio link quality. Also, when the measured radio link quality becomes worse than the set threshold value, the PHY may notify the upper layer (such as RRC) of being out-of-sync

[0151] Based on the above description, various embodiments will be described. Note that the above-described respective processes may be applied to the processes omitted in the following description

[0152] FIG. 5 is a block diagram showing the configuration of the terminal device (UE122) in the present embodiment. To avoid complication of the description, FIG. 5 shows the main components closely related to the present embodiment

[0153] ​​ The UE 122 shown in FIG. 5 includes a receiving unit 500 that receives control information (SCI, MAC control element, RRC signaling, etc.), information including discovery messages and user data, etc. from other terminal devices, and a processing unit 502 that performs processing according to parameters included in the received control information, etc., and and a transmitting unit 504 that transmits control information (SCI, MAC control element, RRC signaling, etc.) and information including discovery messages and user data, etc. to other terminal devices. Also , the receiving unit 500 may receive control information (MAC control element, RRC signaling, etc.) and information including user data from the base station device (gNB 102). Also, the transmitting unit 504 may transmit control information (MAC control element, RRC signaling, etc.) and information including user data to the base station device (gNB 102). Further, the processing unit 502 may include some or all of the functions of various layers (for example, physical layer, MAC layer, RLC layer, PDCP layer, SDAP layer, RRC layer, PC5-S layer, Discovery layer, and application layer). That is, the processing unit 502 may include some or all of a physical layer processing unit (PHY processing unit), a MAC layer processing unit (MAC processing unit), an RLC layer processing unit (RLC processing unit), a PDCP layer processing unit (PDCP processing unit), an SDAP processing unit (SDAP processing unit), an RRC layer processing unit (RRC processing unit), a PC5-S layer processing unit (PC5-S processing unit), a Discovery layer processing unit (Discovery processing unit), and an application layer processing unit.

[0154] FIG. 6 is a block diagram showing the configuration of the base station device (gNB 102) in the present embodiment. Note that to avoid complication of the description, FIG. 6 shows only the main configuration parts closely related to the present embodiment.

[0155] The base station apparatus shown in FIG. 6 includes a transmission unit 604 that transmits control information (DCI, MAC CE, RRC signaling, etc.) to the UE 122, a processing unit 602 that creates control information (DCI, MAC CE, RRC signaling, etc.) and causes the processing unit 502 of the UE 122 to perform processing by transmitting it to the UE 122, and a reception unit 600 that receives control information (UCI, MAC CE, RRC signaling, etc.) from the UE 122. Further, the processing unit 602 may include some or all of the functions of various layers (for example, physical layer, MAC layer, RLC layer, PDCP layer, SDAP layer, RRC layer, and NAS layer). That is, the processing unit 602 may include one or all of a physical layer processing unit, a MAC layer processing unit, an RLC layer processing unit, a PDCP layer processing unit, an SDAP processing unit, an RRC layer processing unit, and a NAS layer processing unit.

[0156] An example of an embodiment of the present invention is shown using FIG. 10.

[0157] The UE 122 that has detected the RLF of the MCG makes a condition determination in step S1000 and operates based on the determination in step S1002.

[0158] In step S1000, the condition may be, for example, some or all of the following multiple conditions. It may be part of. (c-a) The additional procedure for the non-direct path is not ongoing. (c-b) The change procedure for the non-direct path is not ongoing.

[0159] Based on the determination in step S1000 that the condition is satisfied, the UE 122 may report the RLF of the MCG to the base station apparatus in step S1002. Further, based on the determination in step S1000 that the condition is not satisfied, the UE 122 may start the RRC connection re-establishment procedure.

[0160] The additional procedure for the non-direct path refers to the UE 122 that connects to the base station apparatus using only the direct path. may be a procedure for newly establishing an indirect path to the base station apparatus. Establishing a new indirect path may be rephrased as, for example, adding an indirect path via a target relay terminal apparatus. Further, the procedure for changing the indirect path is a procedure for the UE 122, which connects to the base station apparatus using a direct path and an indirect path, i.e., plays the role of a multi-path remote terminal apparatus, to change the indirect path to the base station apparatus and may be so. Changing the indirect path may be rephrased as, for example, changing the relay terminal apparatus that provides the indirect path from a source multi-path relay terminal apparatus to a target multi-path relay terminal apparatus. The base station apparatus may transmit an RRC reconfiguration (RRCReconfiguration) message to the UE 122 and the target multi-path relay terminal apparatus to establish the indirect path. In the case of the procedure for changing the indirect path, the base station apparatus may transmit an RRC reconfiguration (RRCReconfiguration) message to the source multi-path relay terminal apparatus to release the path used before the change of the indirect path. The UE 122 may transmit an RRC reconfiguration complete (RRCReconfigurationComplete) message to the base station apparatus at least via the direct path to complete the procedure for adding an indirect path or changing an indirect path. The UE 122 that has completed the procedure for adding an indirect path or changing the indirect path may transmit and receive data using the direct path and the indirect path. In addition to or instead of (c-a) and (c-b), the condition may be, for example, some or a combination of the following conditions.

[0161] (c-c) Transmission on the indirect path is not suspended (c-d) The UE 122 is set to multi-path (c-e) SRB1 is set as a split bearer and PDCP duplication is also set

[0162] To report the RLF of the MCG to the base station apparatus, the UE 122 may initiate an MCG failure information procedure. The MCG failure information procedure may be equivalently described as initiating a fast MCG recovery procedure to maintain the RRC connection without re-establishment. In the MCG failure information procedure, the UE 122 may transmit an MCG failure information (MCGFailureInformation) message to the base station apparatus. Further, the UE 122 may include a failure type in the MCG failure information message. In addition, among each measurement object (measObjectNR) set by the measurement configuration (measConfig) associated with the MCG, the UE 122 includes an entry for which the measurement result is available in a measurement result frequency list (measResultFreqList), and includes the measurement result frequency list in the MCG failure information message. The entry may include, for example, the physical cell ID of the serving cell or neighboring cells and the measurement results of the cell quality corresponding to each physical cell ID, and may also include information indicating the frequency of the measured SSB or CSI-RS. As the cell quality, measurement quantities such as reference signal received power (RSRP), reference signal received quality (RSRQ), and signal to interference plus noise ratio (SINR) may be specified. The MCG failure information may be transmitted via SRB1. Note that in the above-described embodiment, detecting the RLF of the MCG may be equivalently described as directly detecting the RLF. Similarly, the direct-path RLF may be equivalently described as the RLF of the MCG, and to report the direct-path RLF to the base station apparatus, the UE 122 may initiate an MCG failure information procedure.

[0163] In the above-described embodiment, detecting the RLF of the MCG directly detecting the RLF in a direct path may be equivalently described. Similarly, the direct-path RLF may be equivalently described as the RLF of the MCG, and to report the direct path RLF to the base station apparatus, the UE 122 may initiate an MCG failure information procedure. may.

[0164] In a multi-path relay, when a direct path (MCG) fails, information regarding the failure (MCGFailureInformation) is sent. However, even in a situation where it should not be sent according to existing procedures, a procedure for sending the information regarding the failure is started. By appropriately determining the conditions for sending the information regarding the failure according to the present invention, unnecessary operations of the terminal device can be reduced, and the RRC connection can be quickly restored.

[0165] Also, in the above description, expressions such as "being notified", "receiving a pointing out", etc. may be paraphrased with each other.

[0166] Also, in the above description, expressions such as "associating", "correlating", "relating", etc. may be paraphrased with each other.

[0167] Also, in the above description, expressions such as "being included", "being contained", "having been contained", etc. may be paraphrased with each other.

[0168] Also, in the above description, "the above-mentioned ~" may be paraphrased as "the ~".

[0169] Also, in the above description, expressions such as "determined as ~", "being set as ~", "being included as ~" etc. may be paraphrased with each other.

[0170] Also, in the examples of each process or the examples of each process flow in the above description, some or all of the steps may not be executed. Also, in the examples of each process or the examples of each process flow in the above description, the order of the steps may be different. Also, in the examples of each process or the examples of each process flow in the above description, some or all of the processes within each step may not be executed. Also, in the examples of each process or the examples of each process flow in the above description, the order of the processes within each step may be different. Also, in the above description, "performing B based on the fact that A" may be paraphrased as "performing B". That is, the fact of "performing B" is "the fact that A" It may be executed independently.

[0171] In the above description, "A may be rephrased as B" may include, in addition to rephrasing A as B, rephrasing B as A. Also, in the above description, when "C may be D" and "C may be E" are described, "D may be E" may be included. Also, in the above description, when "F may be G" and "G may be H" are described, "F may be H" may be included.

[0172] Also, in the above description, when the conditions "A" and "B" are contrary conditions, the condition "B" may be expressed as the "other" condition of the condition "A".

[0173] Also, in the above description, "determining whether A is true" may be "determining that A is true" or "determining that A is false". "Determining that A is false" may be "not determining that A is true", and "determining that A is true" may be "not determining that A is false".

[0174] The program that operates on the device according to this embodiment may be a program that controls a Central Processing Unit (CPU) or the like to make a computer function so as to realize the functions of this embodiment. The program or the information handled by the program is temporarily read into a volatile memory such as a Random Access Memory (RAM) during processing, or is stored in a non-volatile memory such as a flash memory or a Hard Disk Drive (HDD), and is read by the CPU as needed and corrected and written.

[0175] Note that a part of the apparatus in the above-described embodiments may be implemented by a computer. In that case, a program for realizing this control function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read into a computer system and executed to be realized. Here, the "computer system" refers to a computer system built in the apparatus, including hardware such as an operating system and peripheral devices. Further, the "computer-readable recording medium" may be any of a semiconductor recording medium, an optical recording medium, a magnetic recording medium, etc.

[0176] Furthermore, the "computer-readable recording medium" also includes those that hold a program dynamically for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, and those that hold a program for a certain time, such as a volatile memory inside a computer system that serves as a server or a client in that case. Also, the above program may be for realizing a part of the aforementioned functions, and furthermore, it may be possible to realize the aforementioned functions in combination with a program already recorded in the computer system.

[0177] In addition, each functional block or various features of the apparatus used in the above-described embodiments can be implemented or executed by an electric circuit, that is, typically an integrated circuit or a plurality of integrated circuits. An electric circuit designed to execute the functions described in this specification is a general-purpose use processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable ​It may include a field programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic, discrete hardware components, or a combination thereof. The general-purpose processor may be a microprocessor, or alternatively the processor may be a conventional processor, controller, microcontroller, or state machine. The general-purpose processor, or each of the circuits described above, may be composed of digital circuits or analog circuits. Further, when an integrated circuit technology that replaces the current integrated circuit appears due to the progress of semiconductor technology, it is also possible to use an integrated circuit based on such technology.

[0178] Note that this embodiment is not limited to the above-described embodiment. In the embodiment, an example of the apparatus has been described, but this embodiment is not limited thereto, and it can be applied to stationary or non-mobile electronic devices installed indoors and outdoors, such as terminal devices or communication devices such as AV devices, kitchen devices, cleaning and washing devices, air conditioning devices, office devices, vending machines, and other household devices.

[0179] As described above, this embodiment has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and design changes and the like within the scope not departing from the gist of this embodiment are also included. Further, this embodiment can be variously modified within the scope shown in the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of this embodiment. Also included is a configuration in which elements described in the above embodiment and having the same effect are replaced with each other.

Description of Reference Numerals

[0180] 100 ng-eNB 102 gNB 110, 112, 114 Interfaces 122 UE 200, 700 PHY 202, 702 MAC 204, 704 RLC 206, 706 PDCP 208, 708 RRC 210 PC5-S 310, 710 SDAP 400 Discovery 500, 600 Receiver 502, 602 Processing Unit 504, 604 Transmitter 712 NAS 800 SRAP

Claims

1. A terminal device that communicates with a base station device, comprising: a receiving unit; a transmitting unit; a processing unit, wherein when the processing unit detects a radio link failure of a direct path, it determines whether a non-direct path change procedure is in progress, and based on the determination that the non-direct path change procedure is not in progress, reports the radio link failure of the direct path to the base station device, wherein the direct path is a path connecting to the base station device via the Uu interface, and the non-direct path is a path connecting to the base station device via a relay terminal device, a terminal device.

2. A method for a terminal device that communicates with a base station device, comprising: when detecting a radio link failure of a direct path, determining whether a non-direct path change procedure is in progress; and based on the determination that the non-direct path change procedure is not in progress, reporting the radio link failure of the direct path to the base station device, wherein the direct path is a path connecting to the base station device using the Uu interface, and the non-direct path is a path connecting to the base station device via another terminal device, a method.

3. An integrated circuit implemented in a terminal device that communicates with a base station device, having: a function of determining whether a non-direct path change procedure is in progress when detecting a radio link failure of a direct path; and a function of reporting the radio link failure of the direct path to the base station device based on the determination that the non-direct path change procedure is not in progress, wherein the direct path is a path connecting to the base station device using the Uu interface, and the non-direct path is a path connecting to the base station device via another terminal device, an integrated circuit.

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