Terminal device, method for terminal device, and base station device

Abstract

A terminal device (10) comprises: a reception unit (122) that receives, from a base station device (20), first information for setting a degree of priority for a logical channel (Logical CHannel, LCH); and a control unit (110) that executes a logical channel prioritization (LCP) procedure. The control unit determines the degree of priority for the LCH in accordance with a threshold value for a prescribed timer on the basis of any of the first information and second information for setting the degree of priority for the LCH.

Description

Terminal device, terminal device method, and base station device CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on and claims the benefit of priority from Japanese Patent Application No. 2024-011495, filed on January 30, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a terminal device, a terminal device method, and a base station device.

[0003] In recent years, technological development related to extended reality (XR) has progressed. XR is a concept that includes multimedia integration technologies such as virtual reality (VR), augmented reality (AR), mixed reality (MR), and substitutional reality (SR). In XR, three-dimensional time-series image data in real space and / or virtual space, audio data of multiple channels (stereo, 5.1ch, etc.), other data presented to the user, control data, etc. are transmitted and received in parallel. XR requires low latency and high reliability to maintain and improve the quality of the user's experience.

[0004] Non-Patent Documents 1 and 2 describe technical specifications defined by the Third Generation Partnership Project (3GPP (registered trademark)), and include technical specifications for supporting XR.

[0005] 3GPP TS 38.321 V18.0.0 (2023-12)3GPP TS 38.331 V18.0.0 (2023-12)3GPP TS 26.522 V0.1.0 (2023-05)

[0006] Non-Patent Document 1 describes a Logical Channel Prioritization (LCP) procedure, which is a process for multiplexing data from different logical channels (Logical CHannel, LCH).

[0007] On the other hand, XR is operated under various requirements, including the requirement of low latency. Non-Patent Document 1 and Non-Patent Document 2 describe technical specifications that take the above requirements into consideration, but do not extend the specifications of the LCP procedure. The inventors have discovered a problem in which resources may not be appropriately allocated to certain data (e.g., data experiencing delays), resulting in the data being discarded. Note that the above problem also occurs in ordinary terminal devices and base station devices other than those implementing XR.

[0008] The present disclosure provides a technique that allows appropriate resource allocation for LCH data in an LCP procedure.

[0009] A terminal device according to the present disclosure includes: a receiving unit configured to receive, from a base station device, a Radio Resource Control (RRC) message including first information for setting a priority for a logical channel (LCH), and a control unit configured to execute a Logical Channel Prioritization (LCP) procedure, wherein the control unit is configured to determine the priority for the LCH based on either the first information or second information for setting the priority for the LCH in accordance with a threshold value for a predetermined timer.

[0010] Furthermore, a method for a terminal device in the present disclosure includes receiving, from a base station device, a Radio Resource Control (RRC) message including first information for setting a priority for a logical channel (LCH), and performing a Logical Channel Prioritization (LCP) procedure, wherein performing the LCP procedure includes determining the priority for the LCH based on either the first information or second information for setting the priority for the LCH in accordance with a threshold value for a predetermined timer.

[0011] Furthermore, the base station device in the present disclosure includes a transmitter (221) configured to transmit a Radio Resource Control (RRC) message including first information for setting a priority for a logical channel (LCH) to a terminal device, wherein in a Logical Channel Prioritization (LCP) procedure, the priority for the LCH is determined based on either the first information or second information for setting the priority for the LCH according to a threshold value for a predetermined timer.

[0012] According to the above configuration, it is possible to appropriately allocate resources to LCH data in the LCP procedure. Note that the above configuration may achieve other effects instead of or in addition to the above effect.

[0013] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which Fig. 1 is a diagram illustrating a communication system S, Fig. 2 is a diagram illustrating a U-plane protocol stack, Fig. 3 is a diagram illustrating a C-plane protocol stack, Fig. 4 is a block diagram illustrating a schematic hardware configuration of a terminal device 10, Fig. 5 is a block diagram illustrating a schematic functional configuration of the terminal device 10, Fig. 6 is a block diagram illustrating a schematic hardware configuration of a base station device 20, Fig. 7 is a block diagram illustrating a schematic functional configuration of the base station device 20, Fig. 8 is a diagram illustrating a radio frame configuration, and Fig. 9 is a diagram illustrating a short BSR (Buffer Status Relay). 16 is a sequence diagram showing the processing flow of the terminal device 10 and the base station device 20. FIG. 17 is a diagram showing the configuration of a PSI-Based SDU Discard Activation / Deactivation MAC CE. FIG. 18 is a diagram for explaining an example of a PSI-based discard process. FIG. 19 is a diagram for explaining an example of a processing flow of an LCP procedure. FIG. 20 is a diagram for explaining an example of selection from first priority information and second priority information. FIG. 22 is an example of a mapping restriction based on a specific condition, FIG. 23 is an example of a mapping restriction based on a specific condition, FIG. 24 is an example of a mapping restriction based on a specific condition, FIG. 25 is an example of a mapping restriction based on a specific condition, and FIG. 26 is a diagram for explaining an example of the processing flow of the LCP procedure.

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and drawings, elements that can be similarly described will be designated by the same reference numerals, and redundant description may be omitted.

[0015] The embodiments described below are merely examples of configurations that can realize the present disclosure. Each of the following embodiments can be modified or changed as appropriate depending on the configuration of the device to which the present disclosure is applied and various conditions. Not all of the combinations of elements included in each of the following embodiments are necessarily essential for realizing the present disclosure, and some of the elements can be omitted as appropriate. Therefore, the scope of the present disclosure is not limited to the configurations described in each of the following embodiments. As long as there are no mutual contradictions, configurations that combine multiple configurations described in the following embodiments can also be adopted.

[0016] 1. First Embodiment 1.1. Communication System As shown in Fig. 1, a communication system S includes one or more terminal apparatuses (Terminal Apparatus) 10, one or more base station apparatuses (Base Station Apparatus) 20, and a core network 30. The communication system S is configured according to predetermined technical specifications. For example, the communication system S may comply with technical specifications (e.g., 5G, 5G Advanced, 6G, etc.) defined by 3GPP.

[0017] In the communication system S, a user plane where user data is transmitted and received and a control plane where control data is transmitted and received are configured separately. That is, the communication system S supports C / U separation. The user plane is abbreviated as U-plane, and the control plane is abbreviated as C-plane.

[0018] The terminal device 10 is a device that wirelessly communicates with the base station device 20 and may be, for example, user equipment (UE) that operates in accordance with the 3GPP 5G NR technical specifications. The terminal device 10 may also be a device that complies with other older or newer 3GPP technical specifications.

[0019] The terminal device 10 may be, for example, a mobile phone terminal such as a smartphone, a tablet terminal, a laptop PC, a communication module, a communication card, or an IoT device such as a surveillance camera or a robot. The terminal device 10 may be a vehicle (e.g., a car, a train, etc.) or a device provided therein. The terminal device 10 may be a transport vehicle other than a vehicle (e.g., a ship, an airplane, etc.) or a device provided therein. The terminal device 10 may be a sensor or a device provided therein. Note that the terminal device 10 may be called by other names such as a terminal, a mobile station, a mobile terminal, a mobile device, a mobile unit, a subscriber station, a subscriber terminal, a subscriber device, a subscriber unit, a wireless station, a wireless terminal, a wireless device, a wireless unit, a remote station, a remote terminal, a remote device, or a remote unit. The terminal device 10 may be a device adapted to one or more of enhanced Mobile Broadband (eMBB), Ultra-Reliable and Low Latency Communications (URLLC), and massive Machine Type Communications (mMTC).

[0020] The base station device 20 manages at least one cell. A cell constitutes the smallest unit of a communication area. For example, one cell belongs to one frequency (e.g., carrier frequency) and is composed of one component carrier. The term "cell" can refer to wireless communication resources and can also refer to a communication target of the terminal device 10. The base station device 20 wirelessly communicates with the terminal device 10 located in its own cell in the U-plane and C-plane. In other words, the base station device 20 terminates the U-plane protocol and C-plane protocol for the terminal device 10.

[0021] The base station device 20 communicates with the core network 30 in the U-plane and the C-plane. More specifically, the core network 30 includes multiple logical nodes including an Access and Mobility Management Function (AMF) and a User Plane Function (UPF). The base station device 20 connects to the AMF in the C-plane and connects to the UPF in the U-plane.

[0022] The base station device 20 may be, for example, a gNB that provides the terminal device 10 with a U-plane and a C-plane conforming to the 3GPP 5G NR technical specifications and connects to the 3GPP 5GC (5G Core Network). The base station device 20 may also be a device conforming to other older or newer 3GPP technical specifications.

[0023] The base station device 20 may be configured by a plurality of unit devices. For example, the base station device 20 may be configured by a central unit (CU), a distributed unit (DU), and a radio unit (RU).

[0024] A radio access network (RAN) is formed by interconnecting multiple base station devices 20. The radio access network formed by the base station devices 20 that are gNBs may be referred to as an NG-RAN. The base station devices 20 that are gNBs may be referred to as NG-RAN nodes.

[0025] The plurality of base station devices 20 are connected to each other via a predetermined interface (for example, an Xn interface). More specifically, for example, the plurality of base station devices 20 are connected to each other via an Xn-U interface in the U-plane and via an Xn-C interface in the C-plane. Note that the plurality of base station devices 20 may also be connected to each other via other interfaces with different functions or names.

[0026] Each base station device 20 is connected to the core network 30 via a predetermined interface (for example, an NG interface). More specifically, for example, each base station device 20 is connected to the UPF of the core network 30 via an NG-U interface in the U-plane, and is connected to the AMF of the core network 30 via an NG-C interface in the C-plane. Note that each base station device 20 may be connected to the core network 30 via another interface with a different function or name.

[0027] The radio protocol architecture between the terminal device 10 and the base station device 20 will be described with reference to Fig. 2. The radio protocol architecture between the terminal device 10 and the base station device 20 and between the terminal device 10 and the core network 30 will be described with reference to Fig. 3.

[0028] As shown in Fig. 2, the U-plane protocol stack includes, from the bottom up, a physical (PHY) layer, a media access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a service data adaptation protocol (SDAP) layer. Each of the above layers is terminated at the base station device 20 on the network side. The MAC layer is also referred to as a "medium access control layer."

[0029] As shown in FIG. 3 , the C-plane protocol stack includes, from the bottom up, a physical (PHY) layer, a media access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, a radio resource control (RRC) layer, and a non-access stratum (NAS). The MAC layer is also referred to as a "medium access control layer." The above-mentioned layers, except for the non-access stratum, are terminated at the base station device 20 on the network side. The non-access stratum is terminated at the AMF of the core network 30 on the network side.

[0030] 4, the terminal device 10 has, as hardware elements, a processor 101, a memory 102, an input / output interface 103, a wireless interface 104, and an antenna 105. The above elements provided in the terminal device 10 are connected to each other by an internal bus. Note that the terminal device 10 may have hardware elements other than the elements shown in FIG. 4.

[0031] The processor 101 is a computing element that realizes various functions of the terminal device 10. The processor 101 may be a system-on-a-chip (SoC) that includes elements such as a central processing unit (CPU), a graphics processing unit (GPU), and a memory controller.

[0032] The memory 102 is composed of at least one storage medium such as a RAM (Random Access Memory) or an eMMC (embedded Multi Media Card). The memory 102 is an element that temporarily or permanently stores programs and data used to execute various processes in the terminal device 10. The programs include one or more instructions for operating the terminal device 10. The processor 101 implements the functions of the terminal device 10 by expanding and executing the programs stored in the memory 102 in the memory 102 and / or a system memory (not shown).

[0033] The input / output interface 103 is an interface that receives operations on the terminal device 10 and supplies the operations to the processor 101, and presents various information to the user. The input / output interface 103 is, for example, a touch panel.

[0034] The wireless interface 104 is a circuit that performs various signal processing to realize wireless communication, and includes a baseband processor and an RF circuit. The wireless interface 104 transmits and receives wireless signals to and from the base station device 20 via an antenna 105.

[0035] 5, the terminal device 10 has, as functional blocks, a control unit 110 and a communication unit 120. The communication unit 120 has at least one transmission unit 121 and at least one reception unit 122.

[0036] The control unit 110 may include at least one processor 101 and at least one memory 102. In other words, the control unit 110 may be realized by the processor 101 and the memory 102. The control unit 110 executes various control processes in the terminal device 10. For example, the control unit 110 controls wireless communication with the base station device 20 via the communication unit 120. That is, the control unit 110 transmits and receives data / information / messages via the communication unit 120.

[0037] The communication unit 120 includes the wireless interface 104 and the antenna 105. In other words, the communication unit 120 is realized by the wireless interface 104 and the antenna 105. The communication unit 120 wirelessly communicates with the base station device 20 by transmitting and receiving wireless signals to and from the base station device 20. Two or more wireless interfaces 104 and two or more antennas 105 may be included in the communication unit 120.

[0038] The control unit 110 operates to execute various processes of the terminal device 10 .

[0039] 6, the base station device 20 has, as hardware elements, a processor 201, a memory 202, a network interface 203, a wireless interface 204, and an antenna 205. The above elements provided in the base station device 20 are connected to each other by an internal bus. Note that the base station device 20 may have hardware elements other than the elements shown in FIG. 6.

[0040] The processor 201 is a computing element that realizes various functions of the base station device 20. The processor 201 may be a CPU, and may further include other processors such as a GPU.

[0041] The memory 202 is configured by at least one storage medium such as a read-only memory (ROM), a RAM, a hard disk drive (HDD), or a solid state drive (SSD). The memory 202 is an element that temporarily or permanently stores programs and data used to execute various processes in the base station device 20. The programs include one or more instructions for operating the base station device 20. The processor 201 implements the functions of the base station device 20 by expanding and executing the programs stored in the memory 202 in the memory 202 and / or a system memory (not shown).

[0042] The network interface 203 is an interface used to transmit and receive signals to and from other base station devices 20 and the core network 30 .

[0043] The wireless interface 204 is a circuit that performs various signal processing to realize wireless communication, and includes a baseband processor and an RF circuit. The wireless interface 204 transmits and receives wireless signals to and from the terminal device 10 via an antenna 205.

[0044] 7, the base station device 20 has, as functional blocks, a control unit 210, a communication unit 220, and a network communication unit 230. The communication unit 220 has at least one transmission unit 221 and at least one reception unit 222.

[0045] The control unit 210 may include at least one processor 201 and at least one memory 202. In other words, the control unit 210 may be realized by the processor 201 and the memory 202. The control unit 210 executes various control processes in the base station device 20. For example, the control unit 210 controls wireless communication with the terminal device 10 via the communication unit 220. That is, the control unit 210 transmits and receives data / information / messages via the communication unit 220. Furthermore, for example, the control unit 210 controls communication with other nodes (e.g., other base station devices 20, nodes of the core network 30) via the network communication unit 230.

[0046] The communication unit 220 includes a wireless interface 204 and an antenna 205. In other words, the communication unit 220 is realized by the wireless interface 204 and the antenna 205. The communication unit 220 wirelessly communicates with the terminal device 10 by transmitting and receiving wireless signals to and from the terminal device 10. Two or more wireless interfaces 204 and two or more antennas 205 may be included in the communication unit 220.

[0047] The network communication unit 230 includes the network interface 203. In other words, the network communication unit 230 is realized by the network interface 203. The network interface 203 transmits and receives signals to and from the network (and thus to the other nodes described above).

[0048] The control unit 210 operates to execute various processes in the base station device 20 .

[0049] 1.2 Radio Resources The terminal device 10 and the base station device 20 communicate with each other wirelessly using radio resources in the frequency domain and the time domain. Radio resources will be described below.

[0050] The transmission method for downlink communication from the base station device 20 to the terminal device 10 is, for example, Orthogonal Frequency Division Multiplexing (OFDM) using a cyclic prefix (CP), i.e., CP-OFDM. The transmission method for uplink communication from the terminal device 10 to the base station device 20 is, for example, the above-mentioned CP-OFDM or DFTS-OFDM in which CP-OFDM is applied after transform precoding that performs discrete Fourier transform (DFT) spreading.

[0051] A cyclic prefix is ​​a redundant signal that functions as a guard period (GP) to prevent inter-symbol interference and inter-carrier interference, and is inserted at the beginning of an OFDM symbol. There are two types of cyclic prefixes: a normal cyclic prefix and an extended cyclic prefix.

[0052] As radio resources in the frequency domain of OFDM, multiple subcarriers that are orthogonal to each other are used. The multiple subcarriers are arranged in the frequency domain at a predetermined subcarrier spacing (sub-carrier spacing, SCS) Δf. Multiple subcarrier spacings Δf can be applied in a communication system S. The subcarrier spacing Δf can be expressed, for example, by the following equation: Δf=2 μ ・15 [kHz]

[0053] Here, μ is an integer equal to or greater than 0 and can take on at least one of the values ​​0, 1, 2, 3, 4, 5, and 6. Therefore, the subcarrier spacing Δf [kHz] can take on at least one of the values ​​15, 30, 60, 120, 240, 480, and 960. Note that μ may also take on a value of 7 or greater.

[0054] In the time domain of OFDM, a layered radio frame structure is used as shown in Figure 8. One radio frame includes 10 subframes. Subframes are assigned subframe numbers that count up by one from 0 to 9. One radio frame is divided into two half frames. The time length of a radio frame is 10 ms, the time length of a half frame is 5 ms, and the time length of a subframe is 1 ms. These time lengths do not depend on the subcarrier spacing Δf.

[0055] One subframe includes one or more slots (slot(s)). The number Ns of slots included in one subframe depends on the value of μ described above, and further depends on the subcarrier spacing Δf. The number Ns of slots is expressed by the following formula, for example: Ns=2 μ

[0056] One slot contains multiple symbols. The number of symbols in one slot depends on the type of cyclic prefix. For example, if a normal cyclic prefix is ​​used, one slot contains 14 symbols. For example, if an extended cyclic prefix is ​​used, one slot contains 12 symbols.

[0057] As described above, the number of slots and the number of symbols included in each of a radio frame, half frame, and subframe, each of which has a fixed time length, are variable. Therefore, the time length of a slot and the time length of a symbol are also variable.

[0058] A resource element (RE) is a radio resource unit in the time-frequency domain consisting of one subcarrier and one symbol, and a resource block (RB) is a radio resource unit in the time-frequency domain consisting of 12 subcarriers and multiple symbols.

[0059] Each radio frame is assigned a system frame number (SFN), which counts up by one from 0 to 1023. SFN "0" corresponds to the initial value of the SFN, and SFN "1023" corresponds to the maximum value of the SFN. Therefore, the radio frame following a radio frame assigned SFN 1023 is assigned SFN 0. Since the time length of a radio frame is 10 ms, the time length of one cycle of the system frame number is 10,240 ms (= 10.24 seconds).

[0060] Here, the base station device 20 may configure one or more serving cells for the terminal device 10. The serving cell may correspond to a component carrier in the downlink and / or a component carrier in the uplink. The technology in which one or more serving cells are configured and the base station device 20 and the terminal device 10 perform wireless communication may also be referred to as carrier aggregation.

[0061] Furthermore, the base station device 20 may configure one or more bandwidth parts (Bandwidth Parts, BWPs) for the terminal device 10 with respect to each of one or more serving cells. For example, a Downlink Bandwidth Part (DL-BWP) may be configured in the downlink of one serving cell. Furthermore, an Uplink Bandwidth Part (UL-BWP) may be configured in the uplink of one serving cell. Herein, the DL-BWP may include an initial DL-BWP and / or a dedicated DL-BWP. Furthermore, the UL-BWP may include an initial UL-BWP and / or a dedicated UL-BWP. Hereinafter, the BWP may include a DL-BWP and / or a UL-BWP.

[0062] 1.3 Channels and Control Information The terminal device 10 and the base station device 20 transmit and receive user data and control information to and from each other. The transmission and reception of control information in the downlink and uplink will be exemplified below.

[0063] The terminal device 10 and the base station device 20 transmit and receive user data and control information using a plurality of hierarchical channels. The physical channel is a channel used for physical communication between the terminal device 10 and the base station device 20. Examples of the physical channel include a physical downlink control channel (PDCCH), a physical broadcast channel (PBCH), and a physical uplink control channel (PUCCH).

[0064] A transport channel is a channel located above a physical channel and is mapped to a physical channel in the PHY layer. Multiple transport channels may be mapped to one physical channel. Examples of transport channels include a Downlink Shared Channel (DL-SCH) and an Uplink Shared Channel (UL-SCH). For example, data in the downlink may also be referred to as DL-SCH data. Furthermore, for example, data in the uplink may also be referred to as UL-SCH data. Here, DL-SCH data includes user data in the downlink. Furthermore, UL-SCH data includes user data in the uplink.

[0065] A logical channel is a channel located above a transport channel and is mapped to the transport channel in the MAC layer. Multiple logical channels may be mapped to one transport channel, and one logical channel may be mapped to multiple transport channels. Logical channels are classified according to the characteristics of the information they transmit. Examples of logical channels include a Broadcast Control Channel (BCCH), a Common Control Channel (CCCH), and a Dedicated Control Channel (DCCH).

[0066] The base station device 20 transmits downlink control information (DCI) to the terminal device 10 using the PDCCH, which is a physical channel. The DCI includes information on downlink and uplink resource allocation for the terminal device 10, and control information for the terminal device 10. The DCI is mapped to the PDCCH and corresponds to Layer 1 signaling.

[0067] Here, one or more formats may be defined for transmission of DCI in the PDCCH. The format defined for transmission of DCI in the PDCCH may be referred to as a DCI format. For example, the DCI format may include a DCI format used for scheduling a Physical Downlink Shared Channel (PDSCH) (e.g., a format referred to as DCI format 1_0, DCI format 1_1, and / or DCI format 1_2). Furthermore, for example, the DCI format may include a DCI format used for scheduling a Physical Uplink Shared Channel (PUSCH) (e.g., a format referred to as DCI format 0_0, DCI format 0_1, and / or DCI format 0_2). Furthermore, the DCI format may include a DCI format not used for scheduling a PDSCH and / or a PUSCH. The DCI format used for scheduling a PDSCH and / or a PUSCH may be referred to as a scheduling DCI format. A DCI format that is not used for scheduling the PDSCH and / or PUSCH may be referred to as a non-scheduling DCI format. Hereinafter, for ease of explanation, a "DCI format" may be simply referred to as a "PDCCH." Furthermore, a "DCI generated according to a DCI format" may be simply referred to as a "DCI format."

[0068] For example, the base station device 20 may configure frequency domain resources and / or time domain resources that the terminal device 10 monitors (i.e., monitors) a PDCCH candidate set. For example, the frequency domain resources that the terminal device 10 monitors the PDCCH candidate set may be referred to as a control resource set (CORESET). Furthermore, the time domain resources that the terminal device 10 monitors the PDCCH candidate set may be referred to as a search space set (SSS). The terminal device 10 may monitor the PDCCH candidate set in one or more CORESETs in the DL-BWP of a serving cell for which PDCCH monitoring is configured, according to the corresponding search space set. Here, monitoring may imply attempting to decode each PDCCH candidate according to the monitored DCI format. The above configuration may be referred to as blind decoding.

[0069] Here, a Cyclic Redundancy Check (CRC) scrambled with a Radio Network Temporary Identifier (RNTI) may be added to the DCI (or DCI format) transmitted on the PDCCH. The CRC may also be referred to as a CRC parity bit. Multiple types of RNTI are defined. For example, the base station device 20 may set each RNTI by transmitting an RRC message including at least one of information indicating a C-RNTI (Cell-RNTI), information indicating a Modulation and Coding Scheme Cell-RNTI (MCS-C-RNTI), and information indicating a Configured Scheduling-RNTI (CS-RNTI). That is, a CRC scrambled with at least one of the C-RNTI, MCS-C-RNTI, and CS-RNTI may be added to the DCI (or DCI format) transmitted on the PDCCH.

[0070] The terminal device 10 may monitor (and / or receive) the PDCCH and detect (and / or receive) the DCI format.

[0071] The terminal device 10 transmits uplink control information (UCI) to the base station device 20 using the PUCCH, which is a physical channel. The UCI includes control information such as a scheduling request (SR), a hybrid automatic repeat reQuest (HARQ) ACK / NACK, and channel state information (CSI). The UCI is mapped to the PUCCH or PUSCH and corresponds to layer 1 signaling.

[0072] The base station device 20 uses the DL-SCH, which is a transport channel, to transmit a control element (CE) of the MAC layer to the terminal device 10. The downlink MAC CE is mapped to the PDSCH via the DL-SCH and corresponds to Layer 2 signaling.

[0073] The terminal device 10 transmits a control element (CE) of the MAC layer to the base station device 20 using the UL-SCH, which is a transport channel. The uplink MAC CE includes control information such as a buffer status report (BSR). The uplink MAC CE is mapped to a PUSCH via the UL-SCH and corresponds to Layer 2 signaling.

[0074] The base station device 20 transmits (or broadcasts) system information (SI) to the terminal device 10 using the BCCH, which is a logical channel. The SI includes minimum system information (MSI) and other system information (OSI). The MSI includes a master information block (MIB) and system information block 1 (SIB1). SIB1 may be referred to as remaining minimum system information (RMSI). The OSI includes system information blocks (SIB2 onward) other than SIB1. Of the BCCH, the MIB is mapped to the PBCH via the BCH (Broadcast CHannel), and the SIB is mapped to the PDSCH via the DL-SCH.

[0075] The base station device 20 transmits control information in the RRC layer to the terminal device 10 using a signaling radio bearer (SRB) established between the terminal device 10 and the base station device 20 in the RRC layer. Hereinafter, messages exchanged between the base station device 20 and the terminal device 10 in the RRC layer may be referred to as RRC messages. There are multiple types of SRBs (e.g., SRB0, SRB1, SRB2, SRB3, SRB4). The SRBs are used to transmit and receive RRC messages as well as NAS messages containing control information in the NAS layer. The CCCH or DCCH is used to transmit RRC messages from the base station device 20 to the terminal device 10. The CCCH and DCCH are each mapped to the PDSCH via the DL-SCH. The RRC message corresponds to Layer 3 signaling.

[0076] As an example of a downlink RRC message, an RRC reconfiguration message will be described. The RRC reconfiguration message is an RRC message transmitted from the base station device 20 to the terminal device 10 using SRB1 or SRB3. The DCCH is used to transmit the RRC reconfiguration message. The RRC reconfiguration message is used to reconfigure or modify the connection between the base station device 20 and the terminal device 10.

[0077] The terminal device 10 transmits an RRC message to the base station device 20 using the above-mentioned SRB. The CCCH or DCCH is used to transmit the RRC message from the terminal device 10 to the base station device 20. The CCCH and DCCH are each mapped to the PUSCH via the UL-SCH. The RRC message corresponds to Layer 3 signaling.

[0078] As an example of an uplink RRC message, a user equipment capability information (UECapabilityInformation) message will be described. The user equipment capability information message is an RRC message transmitted from the terminal device 10 to the base station device 20 using SRB1. The DCCH is used to transmit the user equipment capability information message. The user equipment capability information message is used to notify the base station device 20 of information related to the radio access capability of the terminal device 10.

[0079] As an example of an uplink RRC message, a user equipment assistance information (UE Assistance Information, UAI) message will be described. The UAI message is an RRC message transmitted from the terminal device 10 to the base station device 20 using SRB1 or SRB3. The DCCH is used to transmit the UAI message. The UAI message is used to notify the base station device 20 of various information related to the terminal device 10 (e.g., UE assistance information).

[0080] 1.4. Uplink Scheduling 1.4.1. Scheduling Request (SR) The SR is used by the terminal device 10 to request PUSCH radio resource allocation from the base station device 20. The SR may also be used to request UL-SCH resources for initial transmission. The base station device 20 allocates PUCCH resources for transmitting the SR to the terminal device 10. The base station device 20 transmits an RRC message including SR parameters to the terminal device 10. The SR parameters are included in a SchedulingRequestResourceConfig IE, which is an example of an RRC information element (IE).

[0081] The terminal device 10 transmits UCI including SR to the base station device 20 using the configured PUCCH resource. The terminal device 10 may transmit UCI on demand. The terminal device 10 may transmit UCI at a configured periodicity. For example, the terminal device 10 may transmit an SR set to "0" (negative SR) and / or an SR set to "1" (positive SR). The base station device 20 allocates PUSCH radio resources to the terminal device 10 according to the SR.

[0082] 1.4.2 Dynamic Grant (DG) DG is a scheduling method for allocating radio resources for the PUSCH in accordance with the uplink grant procedure. The base station device 20 transmits an uplink grant to the terminal device 10 via the PDCCH. The terminal device 10 transmits the PUSCH in accordance with the uplink grant. For example, the base station device 20 may allocate radio resources for the PUSCH using a DCI format with a CRC scrambled by the C-RNTI and / or MCS-C-RNTI (i.e., a DCI format used for PUSCH scheduling), and the terminal device 10 may perform uplink transmission using the allocated radio resources for the PUSCH. Here, a new data indicator (New Data Indicator) included in the DCI format to which the CRC scrambled by the C-RNTI and / or MCS-C-RNTI is added may be set to 0 or 1. Furthermore, the base station device 20 may allocate radio resources for the PUSCH using a DCI format with a CRC scrambled by the CS-RNTI (i.e., a DCI format used for scheduling the PUSCH), and the terminal device 10 may perform uplink transmission using the allocated radio resources for the PUSCH. Here, a new data indicator included in the DCI format with a CRC scrambled by the CS-RNTI may be set to 1.

[0083] 1.4.3. Configured Grant (CG) CG is a scheduling method for allocating radio resources for the PUSCH without the above-described dynamic uplink grant procedure. CG includes two types: Type 1 and Type 2. The base station device 20 transmits an RRC message including CG parameters to the terminal device 10. The CG parameters are included in a ConfiguredGrantConfig IE, which is an example of an RRC information element (IE). The ConfiguredGrantConfig IE includes a parameter periodicity related to the periodicity of transmission using the PUSCH. Note that the parameter periodicity is set in units of the number of slots or the number of symbols. Alternatively, the parameter periodicity may be set in units of frames per second (FPS). In Type 1, the terminal device 10 starts transmitting signals at the set periodicity without being triggered by DCI. On the other hand, in Type 2, the base station device 20 transmits DCI scrambled with CS-RNTI to the terminal device 10. The CS-RNTI is used to activate periodic transmission. In response to activation by DCI scrambled with the CS-RNTI, the terminal device 10 starts transmission using the PUSCH at a set period.

[0084] 1.5. LCP (Logical Channel Prioritization) Procedure The terminal device 10 generates a MAC PDU (Medium Access Control Protocol Data Unit) for uplink transmission in accordance with an uplink grant from the base station device 20. When a new transmission is to be performed, the terminal device 10 multiplexes data from multiple different logical channels (Logical Channels, LCHs) to generate a MAC PDU. At this time, the terminal device 10 generates the MAC PDU according to the LCP procedure. The LCP procedure is a priority process for multiplexing data from multiple different LCHs.

[0085] For example, the base station device 20 may transmit an RRC message including parameters related to the LCP procedure to the terminal device 10. For example, the RRC message includes a LogicalChannelConfig IE. The terminal device 10 may generate a MAC PDU based on the LogicalChannelConfig IE included in the RRC message. The LogicalChannelConfig IE may include the following parameters: priority: a value ranging from 1 to 16, representing priority. The smaller the value of the parameter priority, the higher the priority. Hereinafter, this priority will be referred to as "LCH priority" to distinguish it from other priorities (e.g., PHY priority, which will be described later). In the following description, the expression "the value of the parameter priority is relatively small" may be rephrased as "the LCH priority is relatively high." The expression "the value of the parameter priority is relatively large" may be rephrased as "the LCH priority is relatively low." prioritizedBitRate (PBR): represents a prioritized bit rate. bucketSizeDuration (BSD): represents a bucket size duration. The bucket size is determined by PBR x BSD.

[0086] In the LCP procedure, the base station device 20 can set a mapping restriction for the terminal device 10 .

[0087] The terminal device 10 may perform the above mapping restriction based on the LogicalChannelConfig IE included in the RRC message. The LogicalChannelConfig IE may include at least one of the following parameters described in Section 5.4.3.1.1 of Non-Patent Document 1: allowedSCS-List: represents the allowed subcarrier spacing for transmission. maxPUSCH-Duration: represents the maximum PUSCH duration allowed for transmission. configuredGrantType1Allowed: represents whether CG type 1 can be used for transmission. allowedServingCells: represents the cells allowed for transmission. allowedCG-List: represents the CGs allowed for transmission. allowedPHY-PriorityIndex: represents the index of the allowed PHY priority of the DG for transmission. allowedHARQ-mode: represents the allowed uplink HARQ mode for transmission.

[0088] For example, when the allowedCG-List is set for a certain LCH, the terminal device 10 can map data of the LCH only to MAC PDUs corresponding to CGs included in the allowedCG-List.

[0089] For example, when a new transmission is performed, the MAC entity of the terminal device 10 may select an LCH that satisfies the conditions indicated in the mapping restrictions in accordance with Section 5.4.3.1.2 of Non-Patent Document 1.

[0090] Thereafter, the MAC entity allocates resources to the selected LCHs in order of highest LCH priority (i.e., in order of lowest value of the parameter "priority"). For example, the MAC entity allocates the amount of data prioritized by the PBR of each LCH to resources in the MAC PDU in order of LCH priority. If there are still available resources in the MAC PDU after allocating data prioritized by the PBR for all LCHs, the MAC entity allocates the LCH data to the available resources in the MAC PDU in order of LCH priority. The terminal device 10 performs the above procedure until all LCH data is exhausted or until all available resources in the MAC PDU are exhausted.

[0091] More specifically, the MAC entity of the terminal device 10 may allocate resources to the selected LCH in accordance with Section 5.4.3.1.3 of Non-Patent Document 1. The MAC entity of the terminal device 10 may perform the following processes (a1) to (a3).

[0092] (a1) For example, the MAC entity allocates resources in descending order of LCH priority for multiple LCHs selected for uplink grants with Bj > 0. If the PBR of an LCH is set to infinity, the MAC entity allocates resources for all data transmittable on that LCH before satisfying the PBR of an LCH with a lower LCH priority.

[0093] Note that Bj is a variable used in the terminal device 10 in the LCP procedure. The subscript j here is used for association with the LCH. Bj is maintained for each LCHj. The MAC entity initializes Bj of the LCHj to zero when the LCH is established. For LCHj, the MAC entity increments Bj by PBR x T before each instance of the LCP procedure, where T is the time elapsed since Bj was last incremented. If Bj is larger than the bucket size (i.e., PBR x BSD), the MAC entity sets Bj to the bucket size.

[0094] (a2) The MAC entity decrements Bj by the total size of the MAC SDUs served to LCHj.

[0095] (a3) If there are remaining resources, all selected LCHs are served in descending order of LCH priority. That is, the MAC entity allocates the remaining data of all selected LCHs to resources in descending order of LCH priority. At this time, regardless of the value of Bj, the MAC entity allocates the remaining data to resources until either the data of the LCH runs out or the uplink grant resources run out.

[0096] 1.6. Extended Reality (XR) This section describes the characteristics of traffic generated in XR. In XR, multiple types of data (video data, audio data, user data, control data, etc.) are transmitted and received in parallel. The multiple data streams corresponding to the above data each have different traffic characteristics and QoS requirements.

[0097] The timing of sending and receiving the above data can sometimes experience time shifts, which can be expressed as jitter, variability, or fluctuation, due to factors such as video and audio encoding and network delays.

[0098] Reference 1 states that the following definitions may be introduced for transmission and reception in XR: [Reference 1] 3GPP TR 23.700-60 V1.1.0 (2022-09)

[0099] PDU Set: A set of PDUs consisting of one or more PDUs that carry the payload of one unit of information generated at the application level. The application level corresponds, for example, to a frame or a video slice in an XR service. Data Burst: A set of data multiple PDUs generated and transmitted by an application in a short period of time. A PDU in a PDU set may correspond to a PDCP Service Data Unit (SDU).

[0100] Furthermore, in XR, the packet delay budget (PDB) requirement is considered as one of the above QoS requirements. PDB is the upper bound of the allowable packet delay time between the terminal device 10 and the UPF. Reference 1 also describes that the following new QoS parameters may be introduced: PDU-Set Delay Budget (PSDB): This is the upper bound of the allowable PDU set delay time between the terminal device 10 and the UPF. PDU-Set Error Rate (PSER): This is the upper bound of the error rate calculated between a PDU set processed by the sender and all PDUs in the PDU set that are not successfully delivered to the upper layer of the corresponding receiver.

[0101] 1.7 Buffer Status Reporting (BSR) The terminal device 10 transmits a BSR by MAC signaling using the allocated PUSCH radio resources. The BSR is composed of a MAC CE included in a MAC PDU (Medium Access Control Protocol Data Unit). The BSR is used to indicate information about the buffer status of uplink data in the MAC entity. The base station device 20 allocates uplink radio resources to the terminal device 10 based on the BSR.

[0102] In the BSR, LCHs are assigned to logical channel groups (LCGs). Each LCG includes one or more LCHs. The terminal device 10 calculates the buffer size of uplink data for each LCG. The terminal device 10 transmits the buffer size corresponding to each LCG as a BSR to the base station device 20.

[0103] The base station device 20 transmits an RRC message including BSR parameters to the terminal device 10. The BSR parameters are included in a BSR-Config IE, which is an example of an RRC information element (IE). For example, the BSR-Config IE includes three timers: a periodicBSR-Timer, a retxBSR-Timer, and a logicalChannelSR-DelayTimer.

[0104] Furthermore, parameters related to the LCG are included in the LogicalChannelConfig IE, which is an example of an RRC information element (IE). That is, the base station device 20 may transmit an RRC message including the LogicalChannelConfig IE to the terminal device 10. Furthermore, the terminal device 10 may identify the configuration related to the LCH and / or LCG based on the LogicalChannelConfig IE included in the RRC message. For example, the LogicalChannelConfig IE includes a logicalChannelGroup IE. The logicalChannelGroup IE assigns an LCH to an LCG. For example, an LCG index (ID) may be set for each of one or more LCHs, and the LCG to which the one or more LCHs belong may be set. Note that the LogicalChannelConfig IE may include a logicalChannelGroupIAB-Ext IE. The logicalChannelGroupIAB-Ext IE is applied only to IAB-MT (Integrated Access Backhaul-Mobile Termination). If the logicalChannelGroupIAB-Ext IE is set, the LogicalChannelConfig IE is ignored.

[0105] The terminal device 10 may trigger a BSR according to a predetermined condition. For example, the terminal device 10 may trigger a BSR when any of the following conditions (b1) to (b4) is satisfied for an activated cell group. Note that the following conditions may be referred to as "events." (b1) For an LCH belonging to a certain LCG, uplink data becomes available in the MAC entity, and one of the following two conditions is satisfied: - The uplink data belongs to an LCH with a higher priority than an LCH belonging to any LCG that contains available uplink data. - There is no LCH belonging to any LCG that contains available uplink data. (b2) Uplink resources are allocated, and the number of padding bits is equal to or greater than the size of the BSR MAC CE plus its subheader. (b3) The retxBSR-Timer expires, and at least one LCH belonging to the LCG contains uplink data. (b4) The periodic BSR-Timer expires.

[0106] The BSR includes at least a Regular BSR, a Padding BSR, and a Periodic BSR. The Regular BSR, the Padding BSR, and the Periodic BSR may be triggered based on different conditions. For example, the terminal device 10 triggers a Regular BSR when any of the above conditions (b1) and (b3) is satisfied. The terminal device 10 triggers a Padding BSR when the above condition (b2) is satisfied. The terminal device 10 triggers a Periodic BSR when the above condition (b4) is satisfied.

[0107] The BSR includes multiple formats, including at least a short BSR and a long BSR. A MAC PDU including a BSR includes a MAC subheader. The MAC subheader includes a Logical Channel Identifier (LCID) or an extended Logical Channel Identifier (eLCID). The value of the LCID or eLCID may be referred to as a codepoint. The codepoint value identifies the format of the BSR.

[0108] The short BSR is a format for reporting the buffer status (i.e., buffer size) of one LCG. As shown in Figure 9, the short BSR includes one field 900 with a fixed size of 8 bits. The field 900 includes a first part 910 and a second part 920.

[0109] The first part 910 is made up of three bits. The first part 910 is information for identifying the LCG for which the buffer status is reported. The first part 910 is sometimes referred to as an "LCG ID field."

[0110] The second part 920 consists of 5 bits. The second part 920 is information for identifying the total amount of data available in all LCHs included in the LCG indicated by the first part 910. The second part 920 may also be simply referred to as the "buffer size." The second part 920 indicates an index indicating the number of bytes. The terminal device 10 references a predetermined BSR table and sets the second part 920 to an index corresponding to the buffer size. The BSR table has 32 index values ​​(e.g., also referred to as "code points"). For example, the second part 920 indicates one of values ​​0 to 31. Each index value corresponds to a range of buffer sizes. In other words, the above BSR table defines the correspondence between the index and the range of buffer sizes. The smaller the index value, the smaller the buffer size corresponding to that index value. The larger the index value, the larger the buffer size corresponding to that index value.

[0111] The short BSR may include a truncated format, which is a format for a padding BSR, and an extended format, which is a format that allows a larger amount of information to be transmitted.

[0112] The Long BSR is a format for reporting the buffer status (i.e., buffer size) of multiple LCGs. As shown in Figure 10, the Long BSR has a variable size. The Long BSR includes an LCG field 1010 and a buffer size field 1020.

[0113] The LCG field 1010 is composed of 8 bits. In the LCG field 1010, the 8 bits correspond to 8 LCGi, respectively. Here, i is an integer from 0 to 7. The definition of i will remain the same in the following description. The LCG field 1010 may indicate whether a buffer size field for LCGi exists. For example, if the value of LCGi in the LCG field 1010 is 1, this indicates that a buffer size field corresponding to LCGi exists. If the value of LCGi is 0, this indicates that a buffer size field corresponding to LCGi does not exist.

[0114] The number of fields included in the buffer size field 1020 varies depending on the value of the LCG field 1010. It is assumed that the bit corresponding to LCG1 is 1 and the bit corresponding to LCG2 is 1 in the LCG field 1010. Therefore, the buffer size field 1020 includes a field 1021 corresponding to LCG1 and a field 1022 corresponding to LCG2. Note that, since it is assumed that the bit corresponding to LCG0 in FIG. 10 is 0, the buffer size field 1020 does not include a field corresponding to LCG0.

[0115] Each field included in the buffer size field 1020 consists of 8 bits. Each field indicates the buffer size to be reported (e.g., the size of data available for transmission). Each field indicates an index indicating the number of bytes.

[0116] The terminal device 10 refers to the BSR table 1100 shown in FIG. 11 and sets the buffer size field 1020 to an index corresponding to the buffer size.

[0117] The BSR table 1100 has 255 index values ​​(e.g., also referred to as "code points"). The index values ​​range from 0 to 254. Each index value corresponds to a range of buffer sizes. That is, the BSR table 1100 defines the correspondence between the index and the buffer size range. The smaller the index value, the smaller the buffer size corresponding to that index value. The larger the index value, the larger the buffer size corresponding to that index value. Furthermore, each buffer size range corresponding to the 255 index values ​​is defined according to a predetermined exponential function. Therefore, the larger the index value, the larger the buffer size range corresponding to that index value.

[0118] Furthermore, the BSR may include a refined long BSR format to accommodate XR traffic. An additional BSR table 1200 shown in Figure 12 may be defined for the refined long BSR. Hereinafter, the BSR table 1100 in Figure 11 will be referred to as the "first table 1100," and the BSR table 1200 in Figure 12 will be referred to as the "second table 1200."

[0119] Similar to the first table 1100, the second table 1200 is a table for an 8-bit buffer status field. Therefore, the second table 1200 may have 256 index values. The index may be a value from 0 to 255. Each index value may correspond to a range of buffer sizes. That is, the second table 1200 may define a correspondence between the index and the range of buffer sizes. For example, the smaller the index value, the smaller the buffer size corresponding to that index value. The larger the index value, the larger the buffer size corresponding to that index value. Furthermore, each buffer size range corresponding to the 256 index values ​​may be defined according to a predetermined exponential function.

[0120] Furthermore, the range and / or granularity of the second table 1200 may differ from those defined in the first table 1100. Here, the range of the second table 1200 may refer to the range between the minimum and maximum buffer sizes in the second table 1200. Furthermore, the granularity of the second table 1200 may refer to the degree of fineness or coarseness of the division width when the range of the second table 1200 is divided by the number of indexes (e.g., 256). Note that when the ranges of buffer sizes corresponding to the index values ​​are defined according to a predetermined exponential function, the larger the index value, the larger the division width (i.e., the range of buffer sizes) corresponding to the index value.

[0121] For example, the range of the second table 1200 may be narrower than the range of the first table 1100. That is, the narrower range than the first table 1100 may be divided into 256 parts, and an index value may be assigned to each divided range. Therefore, the granularity of the second table 1200 may be finer than that of the first table 1100.

[0122] The base station device 20 may transmit an RRC message including configuration information for the second table 1200 to the terminal device 10. The above configuration information may be included in a MAC-CellGroupConfig IE, which is an example of an RRC information element (IE). For example, the above configuration information may be additionalBSR-TableAllowed included in the MAC-CellGroupConfig IE.

[0123] The additionalBSR-TableAllowed may be "information indicating whether the terminal device 10 is allowed to use the second table 1200 for the LCG." For example, the additionalBSR-TableAllowed is a bit string (i.e., a bitmap) including multiple bits. For example, the leftmost bit is the bit corresponding to LCG ID "0." The second bit from the left is the bit corresponding to LCG ID "1." If the value of the bit is 1, this may indicate that the second table 1200 is allowed to be used in addition to the first table 1100 when reporting the buffer size of the LCG corresponding to the bit. If the value of the bit is 0, this may indicate that the second table 1200 is not allowed to be used when reporting the buffer size of the LCG corresponding to the bit. In other words, if the value of the bit is 0, this may indicate that only the first table 1100 is used when reporting the buffer size of the LCG corresponding to the bit.

[0124] As shown in FIG. 13, the refined long BSR includes an LCG field 1310, a buffer size table (BT) field 1320, and a buffer size field 1330.

[0125] The LCG field 1310 is configured with 8 bits. The LCG field 1310 has the same configuration as the LCG field 1010 in Fig. 10. The LCG field 1310 may indicate whether a buffer size field for LCGi exists.

[0126] The BT field 1320 consists of 8 bits. The BT field 1320 is present only if the value of the corresponding LCG field 1310 is set to 1, and is "reserved" otherwise. Each bit of the BT field 1320 indicates which table was used for the buffer size field 1330 for LCGi. That is, the value of BTi indicates whether the first table 1100 or the second table 1200 was used to indicate the buffer size of LCGi. If the value of BTi is 0, this may indicate that the first table 1100 was used to indicate the buffer size of LCGi. If the value of BTi is 1, this may indicate that the second table 1200 was used to indicate the buffer size of LCGi.

[0127] The number of fields included in the buffer size field 1330 varies depending on the value of the LCG field 1310. It is assumed that the bit corresponding to LCG1 in the LCG field 1310 is 1, and the bit corresponding to LCG2 is 1. Therefore, the buffer size field 1330 includes a field 1331 corresponding to LCG1 and a field 1332 corresponding to LCG2. Note that, since it is assumed that the bit corresponding to LCG0 in FIG. 13 is 0, the buffer size field 1330 does not include a field corresponding to LCG0.

[0128] Further, assume that in the BT field 1320, the bit of BT1 corresponding to LCG1 is 0 and the bit of BT2 corresponding to LCG2 is 1. Therefore, the field 1331 corresponding to LCG1 is set by referring to the first table 1100. Furthermore, the field 1332 corresponding to LCG2 is set by referring to the second table 1200.

[0129] The MAC PDU may include identification information for identifying whether the BSR is a refined long BSR. For example, the MAC subheader may include an LCID or eLCID value (i.e., a code point). An LCID or eLCID value may be defined to indicate that the BSR is a refined long BSR.

[0130] Like the short BSR, the long BSR may include a truncated format and an extended format.

[0131] The BSR may also include a Pre-emptive BSR format and an Extended Pre-emptive BSR format, which are used in the IAB-MT.

[0132] In the case of regular BSR and periodic BSR, a MAC entity whose logicalChannelGroup-IABExt IE is configured by a higher layer may select one of a long BSR, an extended long BSR, and an extended short BSR as follows: (c1) If two or more LCGs have available data for transmission when a MAC PDU containing a BSR is built: (c2) If the maximum value of LCG IDs among the configured LCGs is 7 or less, the terminal device 10 transmits (or reports) a long BSR for all LCGs that have available data. (c2) Otherwise: The terminal device 10 transmits (or reports) an extended long BSR for all LCGs that have available data. (c1) Otherwise: The terminal device 10 transmits (or reports) an extended short BSR.

[0133] In addition, for regular BSR and periodic BSR, a MAC entity for which the logicalChannelGroup-IABExt IE is not set by a higher layer may select one of a short BSR, a long BSR, and a refined long BSR as follows: (d1) If, for at least one LCG for which additionalBSR-TableAllowed is set, the amount of available data for transmission is within the range of the buffer size indicated by the second table 1200: The terminal device 10 transmits (or reports) refined long BSRs for all LCGs that have available data for transmission. (d1) Otherwise: (d2) If, when a MAC PDU including a BSR is constructed, two or more LCGs have available data for transmission: The terminal device 10 transmits (or reports) long BSRs for all LCGs that have available data. (d2) Otherwise: The terminal device 10 transmits (or reports) short BSRs.

[0134] In addition, in the case of a padding BSR, the terminal device 10 may transmit one of the following BSR formats according to the conditions that are met: Short BSR Long BSR Short Truncated BSR Long Truncated BSR Extended Short BSR Extended Long BSR Extended Short Truncated BSR Extended Long Truncated BSR

[0135] The procedure by which the terminal device 10 transmits a BSR MAC CE to the base station device 20 will be described below.

[0136] 14, the communication unit 220 of the base station device 20 transmits an RRC message to the terminal device 10 (S1401). The RRC message includes parameters related to the BSR. The RRC message may be an RRCReconfiguration message.

[0137] The control unit 110 of the terminal device 10 triggers a BSR based on parameters included in the RRC message. For example, the control unit 110 triggers a BSR based on at least one of the above conditions (b1) to (b4). The communication unit 120 of the terminal device 10 transmits the BSR (S1402). The control unit 210 of the base station device 20 allocates radio resources to the terminal device 10 based on the BSR.

[0138] 1.8 Delay Status Reporting (DSR) The terminal device 10 transmits a DSR by MAC signaling using the allocated PUSCH radio resources. The DSR is configured by a MAC CE included in a MAC PDU. The DSR is used by the terminal device 10 to provide the base station device 20 with a delay status of the LCG. The base station device 20 allocates radio resources for the uplink to the terminal device 10 based on the DSR.

[0139] In the DSR, the terminal device 10 reports a delay status (or delay information) for each LCG. The delay status may include the remaining time until a predetermined deadline is reached. For example, the remaining time may be the remaining time of a PDCP discard timer.

[0140] The base station device 20 transmits an RRC message including parameters related to DSR to the terminal device 10. For example, the information regarding the PDCP discard timer may be included in a PDCP-Config IE, which is an example of an RRC information element (IE). The PDCP discard timer may be set for a data radio bearer (DRB). Upon receiving a PDCP SDU (Service Data Unit) from a higher layer, the PDCP entity of the terminal device 10 starts the PDCP discard timer associated with the PDCP SDU.

[0141] Furthermore, parameters related to DSR may be included in a MAC-CellGroupConfig IE, which is an example of an RRC information element (IE). For example, the MAC-CellGroupConfig IE includes information for triggering DSR. Specifically, the MAC-CellGroupConfig IE may include remainingTimeThreshold. The remainingTimeThreshold is a threshold used for the remaining time to trigger DSR for an LCG. The remainingTimeThreshold may be configured for each LCG. Specifically, the remainingTimeThreshold may be configured in association with an LCG ID.

[0142] The MAC entity of the terminal device 10 may trigger DSR for an LCG configured for DSR as follows: The MAC entity may trigger DSR for the LCG when both of the following (e1) and (e2) are met: (e1) The shortest remaining time among multiple PDCP discard timers for all data buffered in the LCG that has not been transmitted in any MAC PDU or reported as a data amount in a DSR MAC CE is less than the remainingTimeThreshold configured for the LCG; and (e2) There is no pending DSR for the LCG since the last transmission of a DSR MAC CE.

[0143] Once a DSR is triggered, it may be considered pending until it is canceled. A MAC entity may cancel a pending DSR when all SDUs associated with the pending DSR are discarded, or when a MAC PDU containing either all SDUs associated with the DSR or a DSR MAC CE containing delay information for all SDUs associated with the DSR is transmitted.

[0144] If there is at least one pending DSR, the MAC entity may instruct the generation of a DSR MAC CE if UL-SCH resources are available for the new transmission and can accommodate the DSR MAC CE and its subheader. The MAC entity may trigger an SR if there is no pending SR (i.e., scheduling request) already triggered by a DSR procedure for the same LCH.

[0145] Furthermore, the terminal device 10 may report the size of predetermined data for each LCG in the DSR. For example, the predetermined data may be the size of the data with a short remaining time, and is referred to as "delay-critical UL data (hereinafter, "Delay-Critical UL data")."

[0146] For the Delay-Critical UL data in a certain LCG, the corresponding PDCP entity and RLC entity may calculate the amount of Delay-Critical UL data as follows:

[0147] The PDCP entity may calculate the amount of Delay-Critical PDCP data by taking into account the following (f1) to (f5): (f1) Delay-Critical PDCP SDUs for which no PDCP data PDUs have been constructed, (f2) PDCP data PDUs that contain Delay-Critical PDCP SDUs and have not been transmitted to a lower layer, (f3) PDCP control PDUs, (f4) PDCP SDUs retransmitted in AM DRBs, and (f5) PDCP data PDUs retransmitted in AM DRBs.

[0148] When pdu-SetDiscard is not set, a Delay-Critical PDCP SDU is a PDCP SDU for which the time remaining until the PDCP discard timer expires is less than remainingTimeThreshold. pdu-SetDiscard is a parameter indicating whether the terminal device 10 performs PDU set-based discard processing in the PDCP entity. pdu-SetDiscard may be included in the PDCP-Config IE. When pdu-SetDiscard is set, a Delay-Critical PDCP SDU is a PDCP SDU belonging to a PDU set for which the time remaining until the PDCP discard timer expires is less than remainingTimeThreshold for at least one PDCP SDU. Note that an AM DRB is a data radio bearer that uses RLC AM (Acknowledge Mode).

[0149] The RLC entity may calculate the amount of Delay-Critical RLC data by taking into account the following (g1) to (g3): (g1) Delay-Critical RLC SDUs or Delay-Critical RLC SDU segments not included in an RLC data PDU, (g2) RLC data PDUs that include Delay-Critical RLC SDUs or Delay-Critical RLC SDU segments and are pending for initial transmission, and (g3) RLC data PDUs that are pending for retransmission in RLC AM.

[0150] A delay-critical RLC SDU is an RLC SDU that corresponds to a PDCP PDU that is indicated as delay-critical by PDCP.

[0151] Therefore, the PDCP entity may indicate to the RLC entity the PDUs containing PDCP SDUs whose remaining time is less than the remainingTimeThreshold, and the PDUs may be considered as Delay-Critical RLC SDUs.The PDUs containing the Delay-Critical RLC SDUs may then be included in the amount of Delay-Critical UL data.

[0152] For example, the terminal device 10 may transmit a DSR MAC CE shown in Fig. 15. As shown in Fig. 15, the DSR MAC CE includes an LCG field 1510 and a delay information field 1520.

[0153] The LCG field 1510 is composed of 8 bits. In the LCG field 1510, the 8 bits correspond to 8 LCGi, respectively. The LCG field 1510 may indicate whether delay information for the LCGi (i.e., the remaining time field and buffer size field, which will be described later) is present in the delay information field 1520. For example, if the value of LCGi in the LCG field 1510 is 1, this may indicate that the remaining time field and buffer size field for the LCGi are present in the delay information field 1520. If the value of LCGi is 0, this may indicate that the remaining time field and buffer size field for the LCGi are not present in the delay information field 1520.

[0154] The number of fields included in the delay information field 1520 varies depending on the value of the LCG field 1510. Assume that in the LCG field 1510, the bit corresponding to LCG1 is 1 and the bit corresponding to LCG2 is 1. Therefore, the delay information field 1520 includes delay information corresponding to LCG1 (i.e., remaining time field 1521 and buffer size field 1522). Furthermore, the delay information field 1520 includes delay information corresponding to LCG2 (i.e., remaining time field 1523 and buffer size field 1524). Note that it is assumed that in the LCG field 1510, the bit corresponding to LCG0 is 0. Therefore, the delay information field 1520 does not include delay information corresponding to LCG0.

[0155] The remaining time field 1521 includes at least a first portion 1521a and a second portion 1521b. Note that "R" in the remaining time field 1521 is a reserved bit.

[0156] The first portion 1521a is composed of one bit and represents a buffer size table (BT). The first portion 1521a may indicate whether the first table 1100 or the second table 1200 was used to indicate the buffer size of LCG1. That is, the first portion 1521a may indicate whether the buffer size field 1522 was set in the first table 1100 or the second table 1200. If the value of the first portion 1521a is 0, this may indicate that the first table 1100 was used to set the buffer size field 1522. If the value of the first portion 1521a is 1, this may indicate that the second table 1200 was used to set the buffer size field 1522.

[0157] The second part 1521b is composed of 6 bits. The second part 1521b represents the remaining time for the data corresponding to LCG1. More specifically, the second part 1521b may represent the shortest remaining time of the PDCP discard timer at the time of the first symbol of the first transmission of the PUSCH including the DSR MAC CE among all PDCP SDUs buffered in LCG1.

[0158] The buffer size field 1522 consists of 8 bits. The buffer size field 1522 indicates the total amount of Delay-Critical UL data for LCG1. If additionalBSR-TableAllowed is set and the buffer size (i.e., the total amount of Delay-Critical UL data) is within the range of buffer sizes indicated by the second table 1200, the MAC entity sets the buffer size field 1522 using the second table 1200. Otherwise, the MAC entity sets the buffer size field 1522 using the first table 1100.

[0159] The remaining time field 1523 has the same configuration as the remaining time field 1521. The remaining time field 1523 includes at least a first portion 1523a and a second portion 1523b. For example, the first portion 1523a indicates whether the buffer size field 1524 is set in the first table 1100 or the second table 1200. For example, the second portion 1523b indicates the above remaining time for the data corresponding to LCG2.

[0160] The buffer size field 1524 has the same configuration as the buffer size field 1522. For example, the buffer size field 1524 indicates the total amount of Delay-Critical UL data for LCG2.

[0161] The MAC PDU may include identification information for identifying whether it is a DSR MAC CE. For example, the MAC subheader may include an LCID or eLCID value indicating that it is a DSR MAC CE.

[0162] The procedure by which the terminal device 10 transmits a DSR MAC CE to the base station device 20 will be described below.

[0163] 16 , the communication unit 220 of the base station device 20 transmits an RRC message to the terminal device 10 (S1601). The RRC message includes parameters related to DSR. The RRC message may be an RRCReconfiguration message.

[0164] The control unit 110 of the terminal device 10 triggers a DSR based on parameters included in the RRC message. For example, if an LCG is configured for DSR, the control unit 110 triggers a DSR for the LCG when both of the above (e1) and (e2) are satisfied. The communication unit 120 of the terminal device 10 transmits a DSR (S1602).

[0165] The control unit 210 of the base station device 20 allocates radio resources to the terminal device 10 based on the DSR. The control unit 210 may determine the degree of delay based on delay information included in the DSR. For example, the control unit 210 may determine the degree of delay based on the remaining time and the amount of Delay-Critical UL data. The control unit 210 may allocate radio resources for uplink communication from the terminal device 10 based on the degree of delay.

[0166] 1.9 PDU Set Importance (PSI) In communications requiring real-time performance such as XR, the Real-time Transport Protocol (RTP) is assumed to be used. An RTP packet includes an RTP payload and an RTP header.

[0167] Non-Patent Document 3 defines fields included in the RTP Header Extension. The importance of the PDU set (i.e., PSI) mentioned above is included in the RTP Header Extension. The PSI is associated with a PDU set and indicates its importance compared to other PDU sets within the same QoS flow.

[0168] The PSI is represented by, for example, 4 bits. The PSI may have a value between 0 and 15. The lower the PSI value, the higher the importance of the PDU set associated with that PSI. For example, a PDU set associated with a PSI of "0" has the highest importance. A PDU set associated with a PSI of "15" has the lowest importance. Therefore, in the following description, the expression "a relatively small PSI value" may be rephrased as "the importance of the corresponding data (i.e., PDU set) is relatively high." The expression "a relatively large PSI value" may be rephrased as "the importance of the corresponding data (i.e., PDU set) is relatively low."

[0169] 1.10. PSI-Based Data Discard Processing The terminal device 10 may perform PSI-based data (e.g., SDU) discard processing. Hereinafter, for ease of notation, such discard processing is also referred to as "PSI-based discard processing" or "PSI-based SDU discard."

[0170] The base station device 20 transmits an RRC message including parameters related to the PSI-based discard process to the terminal device 10. For example, the parameters are included in a PDCP-Config IE, which is an example of an RRC information element (IE). The PDCP-Config IE includes DiscardTimerForLowImportance. DiscardTimerForLowImportance is a discard timer used in the PSI-based discard process and is used for data of relatively low importance (i.e., data with a relatively large PSI value). Hereinafter, the PDCP discard timer that is normally used is referred to as the "first discard timer," and DiscardTimerForLowImportance, which can be used instead of the first discard timer in the PSI-based discard process, is referred to as the "second discard timer." The second discard timer is always set to be shorter than the first discard timer.

[0171] The second discard timer is started in place of the first discard timer when PSI-based discard processing is activated.

[0172] More specifically, the PDCP entity of the terminal device 10 starts the second discard timer associated with a PDCP SDU when, upon receiving the PDCP SDU from the upper layer, the PSI-based discard process is activated, the second discard timer is set, and the PDCP SDU belongs to a PDU set with low importance (i.e., a high PSI value). Otherwise, upon receiving the PDCP SDU from the upper layer, the PDCP entity of the terminal device 10 starts the first discard timer associated with the PDCP SDU.

[0173] The base station device 20 transmits to the terminal device 10 a MAC CE indicating the enabled or disabled state of the PSI-based discard process.

[0174] For example, the base station device 20 may transmit a MAC CE shown in FIG. 17 . This MAC CE may be referred to as a "PSI-Based SDU Discard Activation / Deactivation MAC CE." As shown in FIG. 17 , the MAC CE includes an 8-bit field 1700. In field 1700, Di may indicate, in ascending order of DRB ID, the enabled or disabled state of the PSI-based discard process for the DRBs for which the PSI-based discard process is configured. When the value of Di is 1, this may indicate that the PSI-based discard process is enabled for the DRB corresponding to Di. When the value of Di is 0, this may indicate that the PSI-based discard process is disabled for the DRB corresponding to Di.

[0175] In addition, in the description of Non-Patent Document 1, it may be impossible to identify which DRB Di is directed to. Therefore, if a second discard timer is set for a certain DRB, the DRB may be considered as the above-mentioned "DRB for which PSI-based discard processing is set." With this configuration, it is possible to clearly identify the "DRB for which PSI-based discard processing is set."

[0176] An example of the PSI-based discard process will be described below. As shown in Fig. 18 , the PDCP entity of the terminal device 10 receives a packet 1801 from an upper layer at time t0. The PDCP entity starts a first discard timer from time t0. When the first discard timer expires, the PDCP entity discards the packet 1801.

[0177] At time t1, the terminal device 10 receives the MAC CE shown in FIG. 17 from the base station device 20. Assume that the PSI-based discard process is enabled for the corresponding DRB in the MAC CE. Thereafter, at time t2, the PDCP entity receives packet 1802 from the upper layer. Assume that a second discard timer is configured and that packet 1802 belongs to a PDU set with low importance. In this case, the PDCP entity starts the second discard timer instead of the first discard timer. When the second discard timer expires, the PDCP entity discards packet 1802. The above configuration enables low-importance packets to be discarded early.

[0178] 1.11 Enhancement of the LCP Procedure In the above-described LCP procedure, the parameter "priority" is set for the LCH, but the delay information of the data buffered in the LCH is not taken into account. For example, assume that the LCH priority of LCH1 is higher than that of LCH2. In this situation, if the remaining time for the data buffered in LCH2 becomes shorter, the data buffered in LCH1 takes priority, even though the data in LCH2 should take priority. This may result in the data in LCH2 being discarded due to the expiration of the first discard timer (or the second discard timer). As a result, the capacity may be reduced.

[0179] Below, details of each of the aspects 1 and 2 for solving the above problems will be described.

[0180] 1.12. Example 1 The terminal device 10 may change the priority in the LCP procedure based on a specific condition. Hereinafter, this process may be referred to as a "priority change process based on a specific condition."

[0181] The above specific conditions may include at least one of the following (h1) to (h5). Details of each of the conditions (h1) to (h5) will be described later. (h1) Condition related to DSR trigger (h2) Condition related to Delay-Critical UL data (h3) Condition related to a predetermined timer (h4) Condition related to an instruction from a higher layer (h5) Condition related to MAC CE (i.e., PSI-Based SDU Discard Activation / Deactivation MAC CE) shown in FIG. 17

[0182] The base station device 20 may transmit parameters related to the priority change process based on a specific condition to the terminal device 10. The base station device 20 may transmit the parameters related to the priority change process based on a specific condition using at least one of an RRC message, a MAC CE, and a DCI.

[0183] The parameters related to the priority change process based on a specific condition include parameters related to at least one of the conditions (h1) to (h5). The parameters related to the priority change process based on a specific condition may be configured for an LCH. For example, a LogicalChannelConfig IE may include the parameters related to the priority change process based on a specific condition. The parameters related to the priority change process based on a specific condition may be configured for an LCG. For example, an IE related to an LCG may include the parameters related to the priority change process based on a specific condition. The parameters related to the priority change process based on a specific condition may be configured for a cell group. For example, the parameters related to the priority change process based on a specific condition may be configured in association with a cell group using a MAC-CellGroupConfig IE.

[0184] The parameters related to the priority change processing based on a specific condition may include information that explicitly or implicitly indicates whether or not the priority change processing based on a specific condition is to be applied. The information may indicate that "the priority change processing based on a specific condition is to be applied" or "the priority change processing based on a specific condition is not to be applied." The information may also be a flag indicating that "the priority change processing based on a specific condition is to be applied" or "the priority change processing based on a specific condition is not to be applied."

[0185] Below, several aspects of priority change processing based on specific conditions will be described.

[0186] 1.12.1. Aspect 1-1 Parameters related to priority change processing based on specific conditions may include information about a first priority in the LCP procedure. Hereinafter, information about the first priority will be referred to as "first priority information." The first priority information may be information about priority that is used in the LCP procedure even when specific conditions, described below, are not met.

[0187] The base station device 20 may transmit the first priority information to the terminal device 10 using at least one of an RRC message, a MAC CE, and a DCI.

[0188] The first priority information may be set for each LCH. That is, the first priority information may be information used to determine the priority for an LCH in the LCP procedure. For example, the LogicalChannelConfig IE in the RRC message may include the first priority information. The first priority information may be a parameter used in the existing LCP procedure. That is, the first priority information may be at least one of the above-mentioned parameters priority, prioritizedBitRate, and bucketSizeDuration.

[0189] The first priority information may be set for each LCG. That is, the first priority information may be information used to determine the priority for an LCH belonging to an LCG in an LCP procedure. The first priority information may be set in association with an LCG using an IE related to the LCG in an RRC message. The first priority information may be set for each cell group. For example, the first priority information may be set in association with a cell group using a MAC-CellGroupConfig IE in an RRC message.

[0190] The parameters related to the priority change process based on a specific condition may include information about a second priority in the LCP procedure. Hereinafter, the information about the second priority is referred to as "second priority information." As will be described later, the second priority information is information that is used in place of the first priority information when a specific condition (e.g., at least one of conditions (h1) to (h5)) is satisfied.

[0191] The base station device 20 may use at least one of an RRC message, a MAC CE, and a DCI to transmit the second priority information to the terminal device 10. In another example, the second priority information may be a predefined fixed value.

[0192] The second priority information may be set for each LCH. That is, the second priority information may be information used to determine the priority for an LCH in an LCP procedure. For example, the LogicalChannelConfig IE in an RRC message may include the second priority information.

[0193] The second priority information may include information corresponding to parameters used in the existing LCP procedure. For example, the second priority information may include at least one of information corresponding to the parameter "priority," information corresponding to the parameter "prioritizedBitRate," and information corresponding to the parameter "bucketSizeDuration." Hereinafter, information corresponding to the parameter "priority" as the second priority information may be expressed as "prioritizedForDelayCritical." Information corresponding to the parameter "prioritizedBitRate" as the second priority information may be expressed as "prioritizedBitRateForDelayCritical." Information corresponding to the parameter "bucketSizeDuration" as the second priority information may be expressed as "bucketSizeDurationForDelayCritical."

[0194] The second priority information may be set for each LCG. That is, the second priority information may be information used to determine the priority for an LCH belonging to an LCG in an LCP procedure. The second priority information may be set in association with an LCG using an IE related to the LCG in an RRC message. The second priority information may be set for each cell group. For example, the second priority information may be set in association with a cell group using a MAC-CellGroupConfig IE in an RRC message.

[0195] The second priority information may be set as an offset value using the first priority information as a reference. That is, the second priority information may include information regarding an offset value for the first priority information. In another example, the offset value may be a predefined fixed value. The terminal device 10 may calculate the second priority information based on the first priority information and the offset value.

[0196] When a new transmission is performed (i.e., when the LCP procedure is applied), the terminal device 10 may select either the first priority information or the second priority information based on a specific condition. "Selecting either the first priority information or the second priority information" may be interpreted as "activating or deactivating either the first priority information or the second priority information" or "applying or not applying either the first priority information or the second priority information."

[0197] When a new transmission is performed, the terminal device 10 may select either the first priority information or the second priority information based on specific conditions and perform the LCP procedure using the selected priority information.

[0198] The terminal device 10 may select either the first priority information or the second priority information for each LCH. For example, if second priority information is set for a certain LCH and a specific condition is met for that LCH, the terminal device 10 may select the second priority information for that LCH. If second priority information is set for a certain LCH and a specific condition is not met for that LCH, the terminal device 10 may select the first priority information for that LCH. If second priority information is not set for a certain LCH, the terminal device 10 may select the first priority information.

[0199] The terminal device 10 may select either the first priority information or the second priority information for each LCG. The terminal device 10 may select either the first priority information or the second priority information for each cell group. The processing for each LCH described below may be interpreted as processing for each LCG or each cell group.

[0200] When the second priority information is set, the terminal device 10 may select either the first priority information or the second priority information based on at least one of the conditions (h1) to (h5). The following describes the details of the processing for each of the conditions (h1) to (h5).

[0201] 1.12.2. Condition (h1) When DSR is triggered for a certain LCG, the control unit 110 of the terminal device 10 may select the second priority information for the LCHs belonging to the LCG. When DSR is not triggered for a certain LCG, the control unit 110 may select the first priority information for the LCHs belonging to the LCG. When all SDUs associated with the triggered DSR are discarded or transmitted in a MAC PDU, the control unit 110 may select the first priority information for the LCHs belonging to the LCG.

[0202] 1.12.3 Condition (h2) If a certain LCH (or a certain LCG) has Delay-Critical UL data, the control unit 110 may select the second priority information for the LCH (or an LCH belonging to the LCG). If a certain LCH (or an LCG) does not have Delay-Critical UL data, the control unit 110 may select the first priority information for the LCH (or an LCH belonging to the LCG).

[0203] The phrase "a certain LCH (or a certain LCG) has Delay-Critical UL data" may mean that the Delay-Critical UL data calculated as described above in the RLC layer and / or PDCP layer associated with the LCH (or the LCG) is not zero. That is, the phrase "a certain LCH (or a certain LCG) has Delay-Critical UL data" may mean that the RLC layer and PDCP layer associated with the LCH (or the LCG) have any of the above data (f1) to (f5) and (g1) to (g3).

[0204] In another example, "a certain LCH (or a certain LCG) has Delay-Critical UL data" may mean that the amount of Delay-Critical UL data calculated as described above is equal to or greater than a predetermined data amount threshold. The predetermined data amount threshold may be zero or greater than zero. The predetermined data amount threshold may be set for the LCH (or LCG). That is, parameters related to priority change processing based on a specific condition may include the predetermined data amount threshold.

[0205] 1.12.4. Condition (h3) The control unit 110 may determine whether the remaining time of an associated timer for data buffered in a certain LCH (or a certain LCG) is below a certain threshold at a certain point in time. If the remaining time of the associated timer is below the certain threshold, the control unit 110 may select the second priority information for the LCH (or an LCH belonging to the LCG). If the remaining time of the associated timer is not below the certain threshold, the control unit 110 may select the first priority information for the LCH (or an LCH belonging to the LCG).

[0206] The specific time point may be at least one of the following (i1) to (i3): (i1) when a new transmission is performed (i.e., when the LCP procedure is applied), (i2) when UL-SCH resources become available for a new transmission, or (i3) when the first PUSCH transmission containing data from the LCH occurs (e.g., the first symbol).

[0207] The timer may be a first discard timer or a second discard timer.

[0208] The above-mentioned specific threshold may be set for an LCH or an LCG. The base station device 20 may transmit information regarding the specific threshold to the terminal device 10 using at least one of an RRC message, a MAC CE, and a DCI. The specific threshold may be remainingTimeThreshold used to trigger DSR for an LCG. The specific threshold may be set separately from remainingTimeThreshold.

[0209] For example, if the value of the shortest timer among all PDCP SDUs buffered in a certain LCH (or a certain LCG) at a certain time point falls below a certain threshold, the control unit 110 may select the second priority information for the LCH (or an LCH belonging to the LCG). Otherwise, the control unit 110 may select the first priority information for the LCH (or an LCH belonging to the LCG).

[0210] 1.12.5 Condition (h4) The MAC entity may select either the first priority information or the second priority information based on an instruction from the RLC layer and / or the PDCP layer, which are higher layers. The MAC entity may select the second priority information for an LCH instructed by the RLC layer and / or the PDCP layer, or for an LCH belonging to an LCG instructed by the PDCP layer or the RLC layer.

[0211] For example, the PDCP entity may instruct a lower layer to select either the first priority information or the second priority information based on a predetermined timer associated with an LCH or an LCG and a threshold value for the timer. For example, the PDCP entity may instruct a lower layer to select the second priority information for an LCH or an LCH belonging to an LCG based on the remaining time of the predetermined timer falling below the threshold value for the timer. The predetermined timer may be the first discard timer or the second discard timer. The threshold value for the timer may be the specific threshold value. For example, the threshold value for the timer may be remainingTimeThreshold, which is used to trigger DSR for an LCG. The threshold value for the timer may be set separately from remainingTimeThreshold.

[0212] Similarly, the RLC entity may instruct the lower layer whether to select the first priority information or the second priority information based on a predetermined timer associated with the LCH or LCG and a threshold value for that timer.

[0213] Furthermore, the PDCP entity may instruct a lower layer to select second priority information based on the presence of at least one of the above (f1) to (f5).The RLC entity may instruct a lower layer to select second priority information based on the presence of at least one of the above (g1) to (g3).

[0214] 1.12.6. Condition (h5) When it is indicated that the PSI-based discard process is enabled for a certain DRB based on the MAC CE shown in FIG. 17 , the control unit 110 may select the second priority information for the LCH associated with the DRB.

[0215] When it is indicated that the PSI-based discard process is disabled for a certain DRB based on the MAC CE shown in FIG. 17 , the control unit 110 may select the first priority information for the LCH associated with the DRB.

[0216] 1.12.7 Combination of Conditions (h1) to (h5) The control unit 110 may select either the first priority information or the second priority information based on a combination of two or more of the conditions (h1) to (h5). For example, if a DSR is triggered for a certain LCG, the control unit 110 may select the second priority information for an LCH belonging to the LCG. If a certain LCH (or a certain LCG) does not have Delay-Critical UL data, the control unit 110 may select the first priority information for the LCH (or an LCH belonging to the LCG).

[0217] 1.12.8 Processing Flow The terminal device 10 may execute the LCP procedure as shown in Fig. 19. When a new transmission is to be performed, the control unit 110 selects an LCH that satisfies the conditions indicated by the mapping constraint (S1901). The control unit 110 may select an LCH in accordance with Section 5.4.3.1.2 of Non-Patent Document 1.

[0218] Next, the control unit 110 selects either the first priority information or the second priority information for the selected LCH based on at least one of the conditions (h1) to (h5) (S1902).

[0219] The control unit 110 allocates resources to the selected LCH using the selected priority information (S1903). The control unit 110 may execute the above processes (a1) to (a3) ​​using the selected priority information. Thereafter, the communication unit 120 executes a transmission process to the base station device 20 using the allocated resources.

[0220] Note that if the second priority information includes multiple parameters, only some of the multiple parameters may be set. In this case, in step S1902, the control unit 110 may select only some of the parameters set as the second priority information based on at least one of conditions (h1) to (h5), and select the remaining parameters included in the first priority information. As shown in FIG. 20 , for LCH1, only priorityForDelayCritical is set as the second priority information, and prioritizedBitRateForDelayCritical and bucketSizeDurationForDelayCritical are not set. In this case, if at least one of conditions (h1) to (h5) is satisfied, the control unit 110 may select PriorityForDelayCritical set as the second priority information and PrioritizedBitRate and BucketSizeDuration set as the first priority information.

[0221] 1.12.9. Example of Changing Priority For example, the terminal device 10 may select either the first priority information or the second priority information as shown in FIG. 21 based on condition (h1). In the example of FIG. 21, the parameter priority is set as the first priority information. The parameter priorityForDelayCritical is set as the second priority information. LCH1 belongs to LCG1, and LCH2 and LCH3 belong to LCG2. The second priority information is set for LCH1 and LCH2, and the second priority information is not set for LCH3.

[0222] Before time t10, the priority order of LCHs 1 to 3 is as shown in 2101. The priority order 2101 is determined based on the first priority information.

[0223] At time t10, a DSR is triggered for LCG1. Therefore, the control unit 110 selects the second priority information for LCH1 belonging to LCG1. Meanwhile, the first priority information continues to be used for LCH2 and LCH3. Therefore, the priority rankings of LCH1 to LCH3 are changed to 2102.

[0224] At time t11, a DSR is triggered for LCG2. The control unit 110 selects the second priority information for LCH2, which belongs to LCG2. The second priority information is used for LCH1 and LCH2. On the other hand, since the second priority information is not set for LCH3, the control unit 110 selects the first priority information for LCH3, which belongs to LCG2. The priority rankings of LCH1 to LCH3 are changed to 2103.

[0225] At time t12, all SDUs associated with the DSR for LCG1 are discarded. The control unit 110 selects the first priority information for LCH1 belonging to LCG1. The second priority information continues to be used for LCH2, and the first priority information is also used for LCH3. Therefore, the priority rankings of LCH1 to LCH3 are changed to 2104.

[0226] 1.12.10. Aspect 1-2: The second priority information does not have to be set. For example, in the LCP procedure, the terminal device 10 may preferentially allocate resources to an LCH (or LCG) that satisfies at least one of the conditions (h1) to (h5).

[0227] That is, the terminal device 10 may first allocate resources in decreasing order of priority among LCHs (or LCGs) that satisfy at least one of the conditions (h1) to (h5). Next, the terminal device 10 may allocate resources in decreasing order of priority among LCHs (or LCGs) that do not satisfy at least one of the conditions (h1) to (h5).

[0228] More specifically, the MAC entity of the terminal device 10 may perform the following processes (j1) to (j3).

[0229] (j1) For example, the MAC entity allocates resources to LCHs selected for uplink grants with Bj>0 and having Delay-Critical UL data in descending order of LCH priority. Next, the MAC entity allocates resources to LCHs selected for uplink grants with Bj>0 and no Delay-Critical UL data in descending order of LCH priority. If the PBR of an LCH is set to infinity, the MAC entity allocates resources for all data that can be transmitted on that LCH before satisfying the PBR of an LCH with a lower LCH priority.

[0230] (j2) The MAC entity decrements Bj by the total size of the MAC SDUs served to LCHj.

[0231] (j3) If there are remaining resources, all selected LCHs that have Delay-Critical UL data are served in descending order of LCH priority. That is, the MAC entity allocates resources to the remaining data among all selected LCHs that have Delay-Critical UL data in descending order of LCH priority. At this time, regardless of the value of Bj, the MAC entity allocates resources to the remaining data until either the data for that LCH runs out or the uplink grant resources run out. Next, all selected LCHs that do not have Delay-Critical UL data are served in descending order of LCH priority. That is, the MAC entity allocates resources to the remaining data among all selected LCHs that do not have Delay-Critical UL data in descending order of LCH priority. At this time, regardless of the value of Bj, the MAC entity allocates resources to the remaining data until either the data for that LCH runs out or the uplink grant resources run out.

[0232] The above example is an example in which condition (h2), which is an example of a specific condition, is applied to both processes (a1) and (a3), but is not limited to this example. In the description of the process (j1) above, the part that states "condition (h2) is satisfied" may be replaced with "at least one of conditions (h1) to (h5) is satisfied." In the description of the process (j1) above, the part that states "condition (h2) is not satisfied" may be replaced with "at least one of conditions (h1) to (h5) is not satisfied."

[0233] Furthermore, in the description of the process of (j3) above, the part that describes "condition (h2) is satisfied" may be replaced with "at least one of conditions (h1) to (h5) is satisfied." In the description of the process of (j3) above, the part that describes "condition (h2) is not satisfied" may be replaced with "at least one of conditions (h1) to (h5) is not satisfied."

[0234] Furthermore, at least one of the conditions (h1) to (h5) may be applied to either (a1) or (a3). For example, in the description of the process (j1) above, the part that states "condition (h2) is satisfied" may be replaced with "at least one of conditions (h1) to (h5) is satisfied." In the description of the process (j1) above, the part that states "condition (h2) is not satisfied" may be replaced with "at least one of conditions (h1) to (h5) is not satisfied." On the other hand, the process (j3) above may be replaced with the process (a3). In this way, a specific condition may be applied only to the process (a1).

[0235] In yet another example, the process (j1) above may be replaced with the process (a1). Meanwhile, in the description of the process (j3) above, the part that states "condition (h2) is satisfied" may be replaced with "at least one of conditions (h1) to (h5) is satisfied." In the description of the process (j3) above, the part that states "condition (h2) is not satisfied" may be replaced with "at least one of conditions (h1) to (h5) is not satisfied." In this way, a specific condition may be applied only to the process (a3).

[0236] 1.13. Aspect 2 The terminal device 10 may execute a mapping restriction based on at least one of the conditions (h1) to (h5). Hereinafter, for simplicity, the "mapping restriction based on at least one of the conditions (h1) to (h5)" may be referred to as a "mapping restriction based on a specific condition."

[0237] The base station device 20 may transmit parameters related to mapping restriction based on a specific condition to the terminal device 10. The base station device 20 may transmit parameters related to mapping restriction based on a specific condition using at least one of an RRC message, a MAC CE, and a DCI.

[0238] The parameters related to mapping restriction based on a specific condition include parameters related to at least one of the conditions (h1) to (h5). The parameters related to mapping restriction based on a specific condition may be configured for an LCH. For example, a LogicalChannelConfig IE in an RRC message may include the parameters related to mapping restriction based on a specific condition. The parameters related to mapping restriction based on a specific condition may be configured for an LCG. For example, an IE related to an LCG in an RRC message may include the parameters related to mapping restriction based on a specific condition. The parameters related to mapping restriction based on a specific condition may be configured for a cell group. For example, a MAC-CellGroupConfig IE in an RRC message may include the parameters related to mapping restriction based on a specific condition.

[0239] The parameters related to the mapping restriction based on a specific condition may include information that explicitly or implicitly indicates whether or not to apply the mapping restriction based on a specific condition. The information may indicate that "the mapping restriction based on a specific condition is applied" or "the mapping restriction based on a specific condition is not applied." The information may also be a flag indicating that "the mapping restriction based on a specific condition is applied" or "the mapping restriction based on a specific condition is not applied." As described above, the information indicating whether or not to apply the mapping restriction based on a specific condition may be set for an LCH, an LCG, or a cell group.

[0240] Note that when a parameter related to at least one of the conditions (h1) to (h5) is set, this may implicitly indicate that a mapping restriction based on the specific condition is to be applied. For example, when the above-mentioned specific threshold is set, this may implicitly indicate that a mapping restriction based on the specific condition is to be applied.

[0241] Below, several aspects of mapping restrictions based on specific conditions are described.

[0242] 1.13.1 Aspect 2-1 The control unit 110 may permit mapping based on the satisfaction of at least one of the conditions (h1) to (h5). For example, when a new transmission is performed, if a certain LCH (or a certain LCG) satisfies at least one of the conditions (h1) to (h5), the control unit 110 may select the LCH (or LCG) for the uplink grant.

[0243] For example, the condition (h2) may be applied as follows: If a certain LCH (or a certain LCG) has Delay-Critical UL data, the control unit 110 may select the LCH (or LCG) for the uplink grant.

[0244] As shown in Figure 22, at time t21, LCH1 does not have Delay-Critical UL data. Therefore, the control unit 110 does not allow mapping of LCH1 to PUSCH transmission 2201 corresponding to the uplink grant. Thereafter, at time t22, LCH1 has Delay-Critical UL data. Therefore, the control unit 110 allows mapping of LCH1 to PUSCH transmission 2202 corresponding to the uplink grant.

[0245] For example, condition (h3) may be applied as follows: For data buffered in a certain LCH (or a certain LCG), if the remaining time of an associated timer is below a certain threshold at a certain time point, the control unit 110 may select the LCH (or LCG) for an uplink grant. The timer may be the first discard timer or the second discard timer. The certain time point may be at least one of the above (i1) to (i3). The certain threshold may be remainingTimeThreshold or a threshold different from remainingTimeThreshold.

[0246] As shown in FIG. 23 , assume that a specific threshold (=15 ms) is set for LCH1. At time t30, data arrives for LCH1. The remaining time on the timer associated with LCH1 is 30 ms. At time t31, 10 ms after time t30, the remaining time does not fall below the specific threshold. Therefore, the control unit 110 does not allow mapping of LCH1 to PUSCH transmission 2301 corresponding to the uplink grant. At time t32, 20 ms after time t30, the remaining time falls below the specific threshold. Therefore, the control unit 110 allows mapping of LCH1 to PUSCH transmission 2302 corresponding to the uplink grant.

[0247] According to this aspect, it is possible to set conditions for permitting mapping for each LCH (or LCG), and it is possible to finely control mapping for each LCH (or LCG).

[0248] 1.13.2 Aspect 2-2 The control unit 110 may restrict mapping based on whether at least one of conditions (h1) to (h5) is satisfied. For example, when a new transmission is performed, if a certain LCH (or a certain LCG) satisfies at least one of conditions (h1) to (h5), the control unit 110 does not select the specific LCH (or LCG) for the uplink grant.

[0249] The above-mentioned specific LCH (or LCG) may be an LCH (or LCG) other than an LCH (or LCG) that satisfies at least one of the conditions (h1) to (h5). In other words, the above-mentioned specific LCH (or LCG) may be an LCH (or LCG) that does not satisfy any of the conditions (h1) to (h5).

[0250] The specific LCH (or LCG) may be an LCH (or LCG) configured using at least one of an RRC message, a MAC CE, and a DCI. For example, the specific LCH (or LCG) may be an LCH (or LCG) configured using parameters included in an RRC message.

[0251] In the following examples, it is assumed that the above specific LCH (or LCG) is an LCH (or LCG) that does not satisfy at least one of the conditions (h1) to (h5).

[0252] For example, condition (h2) may be applied as follows. In this case, the above-mentioned specific LCH (or LCG) is an LCH (or LCG) that does not satisfy condition (h2). When a certain LCH (or a certain LCG) does not have Delay-Critical UL data, the control unit 110 may restrict mapping of the LCH (or LCG) to uplink grants.

[0253] As shown in FIG. 24 , at time t40, LCH1 does not have Delay-Critical UL data. LCH2 has Delay-Critical UL data. The control unit 110 restricts mapping of LCH1 to PUSCH transmission 2401 corresponding to the uplink grant. As a result, the control unit 110 may map LCH2 to PUSCH transmission 2401 corresponding to the uplink grant.

[0254] For example, condition (h3) may be applied as follows. In this case, the above-mentioned specific LCH (or LCG) is an LCH (or LCG) that does not satisfy condition (h3). For data buffered in a certain LCH (or a certain LCG), if the remaining time of an associated timer at a certain time point is not below a certain threshold, the control unit 110 may restrict mapping of the LCH (or LCG) to uplink grants. The timer may be the first discard timer or the second discard timer. The above-mentioned specific time point may be at least one of the above-mentioned (i1) to (i3). The above-mentioned specific threshold may be remainingTimeThreshold or a threshold different from remainingTimeThreshold.

[0255] As shown in FIG. 25 , assume that a specific threshold (=20 ms) is set for LCH1 and a specific threshold (=15 ms) is set for LCH2. At time t50, the remaining time on the timer associated with LCH1 is 30 ms. The remaining time on the timer associated with LCH2 is 10 ms. The remaining time on the timer associated with LCH1 does not fall below the specific threshold. Therefore, the control unit 110 restricts mapping of LCH1 to PUSCH transmission 2501 corresponding to the uplink grant. On the other hand, the remaining time on the timer associated with LCH2 falls below the specific threshold. As a result, the control unit 110 may map LCH2 to PUSCH transmission 2501 corresponding to the uplink grant.

[0256] According to this aspect, when at least one of the conditions (h1) to (h5) is set for mapping restriction based on a specific condition, mapping can be restricted for all LCHs (or LCGs) that do not satisfy the condition. Mapping restriction can be controlled with fewer settings.

[0257] 1.13.3 Processing Flow The terminal device 10 may execute the LCP procedure as shown in FIG. 26. When a new transmission is performed, the control unit 110 selects an LCH that satisfies the conditions indicated by the mapping restriction (S2601). If it is set that a mapping restriction based on a specific condition is to be applied, the control unit 110 may select an LCH in accordance with the above-mentioned aspect 2-1 or aspect 2-2. If it is set that a mapping restriction based on a specific condition is not to be applied, the control unit 110 may select an LCH in accordance with the mapping restriction described in section 5.4.3.1.2 of Non-Patent Document 1.

[0258] The control unit 110 allocates resources to the selected LCH using the priority information (S2602). The priority information here includes the above-mentioned priority, prioritizedBitRate, and bucketSizeDuration. The control unit 110 may allocate resources in accordance with Section 5.4.3.1.3 of Non-Patent Document 1.

[0259] 1.14 Combination of Aspect 1 and Aspect 2 At least a part of the above-described Aspect 1 and at least a part of the above-described Aspect 2 may be combined. First, the terminal device 10 may select an LCH according to the above-described Aspect 2-1 or Aspect 2-2. Next, for the selected LCH, the terminal device 10 may allocate resources according to Aspect 1-1 or Aspect 1-2.

[0260] 2. Modifications Although the present disclosure has been described based on the above embodiment, it is understood that the present disclosure is not limited to the embodiment or structure. The present disclosure also encompasses various modifications and modifications within the equivalent range. Other combinations including one or more elements included in the above embodiment are also within the scope and spirit of the present disclosure.

[0261] The words, phrases, and other expressions used in the above embodiments are merely examples and may be replaced with substantially identical or similar expressions. In particular, since the technology according to the above embodiments relates to technical specifications, the expressions in the above embodiments may be replaced with substantially identical or similar expressions in technical specifications (e.g., technical specifications cited in this specification).

[0262] The information transmitted and received in the above embodiment may be contained in the same or a different message or element already described in the technical specifications, or may be contained in a newly defined message or element. The information transmitted and received in the above embodiment may be transmitted and received using a different layer and / or a different channel than those in the above embodiment.

[0263] The means and / or functions provided by the devices described in the above embodiments can be provided by software recorded in a tangible memory device and a computer that executes the software, software alone, hardware alone, or a combination thereof. For example, if any of the above devices is provided by an electronic circuit that is hardware, it can be provided by a digital circuit including a large number of logic circuits, or an analog circuit.

[0264] The device described in the above embodiment executes a program stored in a non-transitory tangible storage medium, and the execution of the program executes a method corresponding to the program.

[0265] 3. Supplementary Notes Some or all of the above embodiments and modified examples may also be described as, but are not limited to, the following supplementary notes. Below, relationships are expressed in which a supplementary note that is subordinate to multiple supplementary notes is subordinate to another supplementary note that is subordinate to multiple supplementary notes. All of the following subordinate relationships of supplementary notes are included in the above embodiments.

[0266] (Supplementary Note A1) A terminal device (10) comprising: a control unit (110) configured to change a priority for a logical channel (Logical CHannel, LCH) based on a predetermined condition in a Logical Channel Prioritization (LCP) procedure and allocate resources to data of the LCH; and a communication unit (120) configured to execute a transmission process to a base station device (20) using the allocated resources.

[0267] (Supplementary Note A2) The terminal device according to Supplementary Note A1, wherein the control unit is configured to select, in the LCP procedure, one of first priority information and second priority information for the LCH based on the predetermined condition.

[0268] (Supplementary Note A3) The terminal device according to Supplementary Note A2, wherein the control unit is configured to: select the second priority information for an LCH or an LCH belonging to a Logical Channel Group (LCG) when the predetermined condition is satisfied for the LCH or the LCG; and select the first priority information for the LCH or the LCH belonging to the LCG when the predetermined condition is not satisfied for the LCH or the LCG.

[0269] (Supplementary Note A4) The terminal device according to Supplementary Note A3, wherein the predetermined condition includes a condition that a delay status report (DSR) is triggered for an LCG, and the control unit is configured to select the second priority information for an LCH belonging to the LCG for which the DSR is triggered.

[0270] (Supplementary Note A5) The terminal device according to Supplementary Note A3 or A4, wherein the predetermined condition includes a condition that an LCH or an LCG has delay-critical uplink data, and the control unit is configured to select the second priority information for an LCH having the delay-critical uplink data or an LCH belonging to an LCG having the delay-critical uplink data.

[0271] (Supplementary Note A6) The terminal device according to any one of Supplementary Notes A3 to A5, wherein the predetermined condition includes a condition that a timer associated with an LCH or an LCG falls below a predetermined threshold at a predetermined time point, and the control unit is configured to select the second priority information for an LCH whose timer falls below the predetermined threshold or an LCH belonging to an LCG whose timer falls below the predetermined threshold.

[0272] (Supplementary Note A7) The terminal device according to Supplementary Note A6, wherein the timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance that is a discard timer used in a data discard process based on Protocol Data Unit Set Importance (PSI).

[0273] (Supplementary Note A8) The terminal device according to Supplementary Note A6 or A7, wherein the predetermined threshold is a threshold used to trigger a Delay Status Reporting (DSR).

[0274] (Supplementary Note A9) The terminal device according to any one of Supplementary Notes A6 to A8, wherein the predetermined time point includes at least one of: a time point when a new transmission is performed; a time point when Uplink Shared Channel (UL-SCH) resources become available for a new transmission; and a time point of a first Physical Uplink Shared Channel (PUSCH) transmission including data from an LCH.

[0275] (Supplementary Note A10) The terminal device according to any one of Supplementary Notes A3 to A9, wherein the predetermined condition includes a condition that an instruction is received from a Packet Data Convergence Protocol (PDCP) layer or a Radio Link Control (RLC) layer, and the control unit is configured to select the second priority information for an LCH instructed from the PDCP layer or the RLC layer, or an LCH belonging to an LCG instructed from the PDCP layer or the RLC layer.

[0276] (Supplementary Note A11) The terminal device according to any one of Supplementary Notes A3 to A10, wherein the predetermined condition includes a condition that information for enabling a data discard process based on a Protocol Data Unit Set Importance (PSI) has been received, and the control unit is configured to select the second priority information for an LCH associated with a Data Radio Bearer (DRB) for which the data discard process based on the PSI has been enabled.

[0277] (Supplementary Note A12) The terminal device according to any one of Supplementary Notes A2 to A11, wherein the communication unit is configured to receive the first priority information and the second priority information from the base station device.

[0278] (Supplementary Note A13) The terminal device according to any one of Supplementary Notes A2 to A11, wherein the communication unit is configured to receive the first priority information and information relating to an offset for the first priority information from the base station device, and the control unit is configured to calculate the second priority information using the first priority information and information relating to the offset.

[0279] (Supplementary Note A14) The terminal device according to Supplementary Note A1, wherein the control unit is configured to allocate resources preferentially to data of an LCH that satisfies the predetermined condition in the LCP procedure.

[0280] (Supplementary Note A15) The terminal device according to Supplementary Note A14, wherein the predetermined condition includes a condition that a Delay Status Reporting (DSR) is triggered for a Logical Channel Group (LCG), and the control unit is configured to preferentially allocate resources to data of an LCH belonging to the LCG for which the DSR is triggered.

[0281] (Supplementary Note A16) The terminal device according to Supplementary Note A14 or A15, wherein the predetermined condition includes a condition that an LCH or a Logical Channel Group (LCG) has delay-critical uplink data, and the control unit is configured to preferentially allocate resources to the LCH having the delay-critical uplink data or data of an LCH belonging to the LCG having the delay-critical uplink data.

[0282] (Supplementary Note A17) The terminal device according to any one of Supplementary Notes A14 to A16, wherein the predetermined condition includes a condition that a timer associated with an LCH or a Logical Channel Group (LCG) falls below a predetermined threshold at a predetermined time point, and the control unit is configured to preferentially allocate resources to data of an LCH whose timer falls below the predetermined threshold, or data of an LCH belonging to an LCG whose timer falls below the predetermined threshold.

[0283] (Supplementary Note A18) The terminal device according to Supplementary Note A17, wherein the timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance that is a discard timer used in a data discard process based on a Protocol Data Unit Set Importance (PSI).

[0284] (Supplementary Note A19) The terminal device according to Supplementary Note A17 or A18, wherein the predetermined threshold is a threshold used to trigger a Delay Status Reporting (DSR).

[0285] (Supplementary Note A20) The terminal device according to any one of Supplementary Notes A17 to A19, wherein the predetermined time point includes at least one of: a time point when a new transmission is performed; a time point when Uplink Shared Channel (UL-SCH) resources become available for a new transmission; and a time point of a first Physical Uplink Shared Channel (PUSCH) transmission including data from an LCH.

[0286] (Supplementary Note A21) The terminal device according to any one of Supplementary Notes A14 to A20, wherein the predetermined condition includes a condition that an instruction is received from a Packet Data Convergence Protocol (PDCP) layer or a Radio Link Control (RLC) layer, and the control unit is configured to preferentially allocate resources to data of an LCH instructed from the PDCP layer or the RLC layer, or data of an LCH belonging to an LCG instructed from the PDCP layer or the RLC layer.

[0287] (Supplementary Note A22) The terminal device according to any one of Supplementary Notes A14 to A21, wherein the predetermined condition includes a condition that information for enabling a data discard process based on a Protocol Data Unit Set Importance (PSI) has been received, and the control unit is configured to preferentially allocate resources to data of an LCH associated with a Data Radio Bearer (DRB) for which the data discard process based on the PSI has been enabled.

[0288] (Supplementary Note A23) A method for a terminal device (10), comprising: in a Logical Channel Prioritization (LCP) procedure, changing a priority for a Logical Channel (Logical CHannel, LCH) based on a predetermined condition, and allocating resources for data of the LCH; and executing a transmission process to a base station device (20) using the allocated resources.

[0289] (Appendix A24) A program causing a processor (101) in a terminal device (10) to execute the following: in a Logical Channel Prioritization (LCP) procedure, changing the priority of a logical channel (Logical CHannel, LCH) based on a predetermined condition, and allocating resources to data of the LCH; and executing a transmission process to a base station device (20) using the allocated resources.

[0290] (Appendix A25) A non-transient tangible recording medium having recorded thereon a program that causes a processor (101) in a terminal device (10) to execute the following: in a Logical Channel Prioritization (LCP) procedure, change the priority of a logical channel (Logical CHannel, LCH) based on a predetermined condition, and allocate resources to data of the LCH; and execute a transmission process to a base station device (20) using the allocated resources.

[0291] (Supplementary Note A26) A terminal device (10) comprising: a control unit (110) configured to allow or restrict mapping of a logical channel (Logical CHannel, LCH) based on a predetermined condition and allocate resources to data of the LCH in a Logical Channel Prioritization (LCP) procedure; and a communication unit (120) configured to execute a transmission process to a base station device (20) using the allocated resources.

[0292] (Supplementary Note A27) The terminal device according to Supplementary Note A26, wherein the control unit is configured to select, for an uplink grant, an LCH or an LCH belonging to a Logical Channel Group (LCG) when a predetermined condition is satisfied for the LCH or the LCG.

[0293] (Supplementary Note A28) The terminal device according to Supplementary Note A27, wherein the predetermined condition includes a condition that a Delay Status Reporting (DSR) is triggered for an LCG, and the control unit is configured to select, for the uplink grant, an LCH belonging to the LCG for which the DSR is triggered.

[0294] (Supplementary Note A29) The terminal device according to Supplementary Note A27 or A28, wherein the predetermined condition includes a condition that a timer associated with an LCH or an LCG falls below a predetermined threshold at a predetermined time point, and the control unit is configured to select, for the uplink grant, an LCH whose timer falls below the predetermined threshold or an LCH belonging to an LCG whose timer falls below the predetermined threshold.

[0295] (Supplementary Note A30) The terminal device according to Supplementary Note A29, wherein the timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance that is a discard timer used in a data discard process based on a Protocol Data Unit Set Importance (PSI).

[0296] (Supplementary Note A31) The terminal device according to Supplementary Note A29 or A30, wherein the predetermined threshold is a threshold used to trigger a Delay Status Reporting (DSR).

[0297] (Supplementary Note A32) The terminal device according to any one of Supplementary Notes A29 to A31, wherein the predetermined time point includes at least one of: a time point when a new transmission is performed; a time point when Uplink Shared Channel (UL-SCH) resources become available for a new transmission; and a time point of a first Physical Uplink Shared Channel (PUSCH) transmission including data from an LCH.

[0298] (Supplementary Note A33) The terminal device according to any one of Supplementary Notes A27 to A32, wherein the predetermined condition includes a condition that an instruction is received from a Packet Data Convergence Protocol (PDCP) layer or a Radio Link Control (RLC) layer, and the control unit is configured to select, for the uplink grant, an LCH instructed from the PDCP layer or the RLC layer, or an LCH belonging to an LCG instructed from the PDCP layer or the RLC layer.

[0299] (Supplementary Note A34) The terminal device according to any one of Supplementary Notes A27 to A33, wherein the predetermined condition includes a condition that information for enabling a data discard process based on a Protocol Data Unit Set Importance (PSI) has been received, and the control unit is configured to select, for the uplink grant, an LCH associated with a Data Radio Bearer (DRB) for which the data discard process based on the PSI has been enabled.

[0300] (Supplementary Note A35) The terminal device according to Supplementary Note A26, wherein the control unit is configured not to select a predetermined LCH or Logical Channel Group (LCG) for an uplink grant when a predetermined condition is satisfied for the LCH or LCG.

[0301] (Supplementary Note A36) The terminal device according to Supplementary Note A35, wherein the predetermined LCH or LCG is an LCH or LCG for which the predetermined condition is not satisfied.

[0302] (Supplementary Note A37) The terminal device according to Supplementary Note A35 or A36, wherein the predetermined condition includes a condition that a Delay Status Reporting (DSR) is triggered for an LCG.

[0303] (Supplementary Note A38) The terminal device according to any one of Supplementary Notes A35 to A37, wherein the predetermined condition includes a condition that a timer associated with an LCH or an LCG falls below a predetermined threshold at a predetermined time point.

[0304] (Supplementary Note A39) The terminal device according to Supplementary Note A38, wherein the timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance that is a discard timer used in a data discard process based on a Protocol Data Unit Set Importance (PSI).

[0305] (Supplementary Note A40) The terminal device according to Supplementary Note A38 or A39, wherein the predetermined threshold is a threshold used to trigger a Delay Status Reporting (DSR).

[0306] (Supplementary Note A41) The terminal device according to any one of Supplementary Notes A38 to A40, wherein the predetermined time point includes at least one of: a time point when a new transmission is performed; a time point when Uplink Shared Channel (UL-SCH) resources become available for a new transmission; and a time point of a first Physical Uplink Shared Channel (PUSCH) transmission including data from an LCH.

[0307] (Supplementary Note A42) The terminal device according to any one of Supplementary Notes A35 to A41, wherein the predetermined condition includes a condition that an instruction is received from a Packet Data Convergence Protocol (PDCP) layer or a Radio Link Control (RLC) layer.

[0308] (Supplementary Note A43) The terminal device according to any one of Supplementary Notes A35 to A42, wherein the predetermined condition includes a condition that information for enabling a data discard process based on a Protocol Data Unit Set Importance (PSI) has been received.

[0309] (Supplementary Note A44) A method for a terminal device (10), comprising: in a Logical Channel Prioritization (LCP) procedure, allocating resources for data of a Logical Channel (Logical CHannel, LCH) by permitting or restricting mapping of the LCH based on predetermined conditions; and performing transmission processing to a base station device (20) using the allocated resources.

[0310] (Appendix A45) A program that causes a processor (101) in a terminal device (10) to execute the following: in a Logical Channel Prioritization (LCP) procedure, permitting or restricting mapping of a Logical Channel (LCH) based on predetermined conditions, and allocating resources for data of an LCH; and executing transmission processing to a base station device (20) using the allocated resources.

[0311] (Appendix A46) A non-transient tangible recording medium having recorded thereon a program that causes a processor (101) in a terminal device (10) to perform the following: in a Logical Channel Prioritization (LCP) procedure, permitting or restricting mapping of a Logical Channel (LCH) based on predetermined conditions, and allocating resources for data of an LCH; and performing transmission processing for a base station device (20) using the allocated resources.

[0312] (Supplementary Note B1) A terminal device (10) comprising: a receiving unit (122) configured to receive a Radio Resource Control (RRC) message from a base station device (20) including first information for setting a priority for a logical channel (LCH); and a control unit (110) configured to perform a Logical Channel Prioritization (LCP) procedure, wherein the control unit is configured to determine the priority for the LCH based on either the first information or second information for setting the priority for the LCH according to a threshold value for a predetermined timer.

[0313] (Supplementary Note B2) The terminal device according to Supplementary Note B1, wherein the control unit is configured to: determine the priority for the LCH based on either the first information or the second information when the RRC message includes the second information; and determine the priority for the LCH based on the first information when the RRC message does not include the second information.

[0314] (Supplementary Note B3) The terminal device according to Supplementary Note B1 or B2, wherein the receiving unit is configured to receive an RRC message including third information from the base station device, wherein the third information includes at least one of information for setting a prioritized bit rate (PBR) for the LCH and information for setting a bucket size duration (BSD) for the LCH, and the control unit is configured to determine at least one of the PBR and the BSD for the LCH based on either the third information or fourth information in accordance with the threshold for the predetermined timer, and the fourth information includes at least one of information for setting the PBR for the LCH and information for setting the BSD for the LCH.

[0315] (Supplementary Note B4) The terminal device according to any one of Supplementary Notes B1 to B3, wherein the control unit is configured to allocate resources to the LCH based on the determined priority for the LCH in the LCP procedure.

[0316] (Supplementary Note B5) The terminal device according to any one of Supplementary Notes B1 to B4, wherein the control unit is configured to: determine the priority for the LCH based on the second information when the LCH has predetermined data; and determine the priority for the LCH based on the first information when the LCH does not have the predetermined data.

[0317] (Supplementary Note B6) The terminal device according to Supplementary Note B5, wherein the predetermined data is associated with the predetermined timer, and the predetermined data is data indicating that the remaining time of the predetermined timer falls below the threshold value for the predetermined timer on a predetermined occasion.

[0318] (Supplementary Note B7) The terminal device according to Supplementary Note B6, wherein the predetermined occasion includes at least one of: when a new transmission is performed; when the LCP procedure is applied; when Uplink Shared Channel (UL-SCH) resources become available for a new transmission; and when a Physical Uplink Shared Channel (PUSCH) including data of the LCH is transmitted.

[0319] (Supplementary Note B8) The terminal device according to any one of Supplementary Notes B1 to B7, wherein the predetermined timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance, which is a discard timer used in data discard processing based on Protocol Data Unit Set Importance (PSI).

[0320] (Supplementary Note B9) The terminal device according to any one of Supplementary Notes B1 to B8, wherein the receiving unit is configured to receive, from the base station device, an RRC message including information for setting the threshold value for the predetermined timer for the LCH.

[0321] (Supplementary Note B10) A method for a terminal device (10), comprising: receiving a Radio Resource Control (RRC) message from a base station device, the Radio Resource Control (RRC) message including first information for setting a priority for a logical channel (LCH); and performing a Logical Channel Prioritization (LCP) procedure, wherein performing the LCP procedure comprises determining the priority for the LCH based on either the first information or second information for setting the priority for the LCH according to a threshold value for a predetermined timer.

[0322] (Supplementary Note B11) The method according to Supplementary Note B10, wherein determining the priority for the LCH includes: determining the priority for the LCH based on either the first information or the second information when the RRC message includes the second information; and determining the priority for the LCH based on the first information when the RRC message does not include the second information.

[0323] (Supplementary Note B12) The method according to Supplementary Note B10 or B11, further comprising receiving an RRC message from the base station device, the RRC message including third information, the third information including at least one of information for setting a prioritized bit rate (PBR) for the LCH and information for setting a bucket size duration (BSD) for the LCH, the method further comprising determining at least one of the PBR and the BSD for the LCH based on either the third information or fourth information in accordance with the threshold value for the predetermined timer, and the fourth information including at least one of information for setting the PBR for the LCH and information for setting the BSD for the LCH.

[0324] (Supplementary Note B13) The method according to any one of Supplementary Notes B10 to B12, further comprising, in the LCP procedure, allocating resources to the LCH based on the determined priority for the LCH.

[0325] (Supplementary Note B14) The method according to any one of Supplementary Notes B10 to B13, wherein determining the priority for the LCH includes: determining the priority for the LCH based on the second information when the LCH has predetermined data; and determining the priority for the LCH based on the first information when the LCH does not have the predetermined data.

[0326] (Supplementary Note B15) The method according to Supplementary Note B14, wherein the predetermined data is associated with the predetermined timer, and the predetermined data is data indicating that the remaining time of the predetermined timer falls below the threshold value for the predetermined timer on a predetermined occasion.

[0327] (Supplementary Note B16) The method according to Supplementary Note B15, wherein the predetermined occasions include at least one of: when a new transmission is performed; when the LCP procedure is applied; when Uplink Shared Channel (UL-SCH) resources become available for a new transmission; and when a Physical Uplink Shared Channel (PUSCH) including data of the LCH is transmitted.

[0328] (Supplementary Note B17) The method according to any one of Supplementary Notes B10 to B16, wherein the predetermined timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance, which is a discard timer used in discarding data based on Protocol Data Unit Set Importance (PSI).

[0329] (Supplementary Note B18) The method according to any one of Supplementary Notes B10 to B17, further comprising receiving, from the base station device, an RRC message including information for setting the threshold for the predetermined timer for the LCH.

[0330] (Supplementary Note B19) A base station device (20) comprising: a transmitter (221) configured to transmit, to a terminal device (10), a Radio Resource Control (RRC) message including first information for setting a priority for a logical channel (LCH); and in a Logical Channel Prioritization (LCP) procedure, the priority for the LCH is determined based on either the first information or second information for setting the priority for the LCH according to a threshold value for a predetermined timer.

[0331] (Supplementary Note B20) The base station device according to Supplementary Note B19, wherein, if the RRC message includes the second information, the priority for the LCH is determined based on either the first information or the second information, and if the RRC message does not include the second information, the priority for the LCH is determined based on the first information.

[0332] (Supplementary Note B21) The base station device according to Supplementary Note B19 or B20, wherein the transmitter is configured to transmit an RRC message including third information to the terminal device, wherein the third information includes at least one of information for setting a prioritized bit rate (PBR) for the LCH and information for setting a bucket size duration (BUCKETSIZEDURATION, BSD) for the LCH, and at least one of the PBR and the BSD for the LCH is determined based on either the third information or fourth information in accordance with the threshold value for the predetermined timer, and the fourth information includes at least one of information for setting the PBR for the LCH and information for setting the BSD for the LCH.

[0333] (Supplementary Note B22) The base station device according to any one of Supplementary Notes B19 to B21, wherein in the LCP procedure, resources are allocated to the LCH based on the determined priority for the LCH.

[0334] (Supplementary Note B23) The base station device according to any one of Supplementary Notes B19 to B22, wherein, when the LCH has predetermined data, the priority for the LCH is determined based on the second information, and when the LCH does not have the predetermined data, the priority for the LCH is determined based on the first information.

[0335] (Supplementary Note B24) The base station device according to Supplementary Note B23, wherein the predetermined data is associated with the predetermined timer, and the predetermined data is data in which the remaining time of the predetermined timer falls below the threshold for the predetermined timer on a predetermined occasion.

[0336] (Supplementary Note B25) The base station device according to Supplementary Note B24, wherein the predetermined occasion includes at least one of: when a new transmission is performed; when the LCP procedure is applied; when Uplink Shared Channel (UL-SCH) resources become available for a new transmission; and when a Physical Uplink Shared Channel (PUSCH) including data of the LCH is transmitted.

[0337] (Supplementary Note B26) The base station device according to any one of Supplementary Notes B19 to B25, wherein the predetermined timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance, which is a discard timer used in data discard processing based on Protocol Data Unit Set Importance (PSI).

[0338] (Supplementary Note B27) The base station device according to any one of Supplementary Notes B19 to B26, wherein the transmitter is configured to transmit, to the terminal device, an RRC message including information for setting the threshold for the predetermined timer for the LCH.

[0339] The disclosures of the above prior art documents and references are incorporated herein by reference.

Claims

1. A terminal device (10) comprising: a receiving unit (122) configured to receive a Radio Resource Control (RRC) message including first information for setting a priority for a logical channel (LCH) from a base station device (20); and a control unit (110) configured to perform a Logical Channel Prioritization (LCP) procedure, wherein the control unit is configured to determine the priority for the LCH based on either the first information or second information for setting the priority for the LCH according to a threshold value for a predetermined timer.

2. The terminal device according to claim 1, wherein the control unit is configured to: determine the priority for the LCH based on either the first information or the second information when the RRC message includes the second information; and determine the priority for the LCH based on the first information when the RRC message does not include the second information.

3. The terminal device according to claim 1 or 2, wherein the receiving unit is configured to receive an RRC message including third information from the base station device, the third information including at least one of information for setting a prioritized bit rate (PBR) for the LCH and information for setting a bucket size duration (BUCKETSIZEDURATION, BSD) for the LCH, the control unit is configured to determine at least one of the PBR and the BSD for the LCH based on either the third information or fourth information in accordance with the threshold value for the predetermined timer, and the fourth information including at least one of information for setting the PBR for the LCH and information for setting the BSD for the LCH.

4. The terminal device according to any one of claims 1 to 3, wherein the control unit is configured to allocate resources to the LCH based on the determined priority for the LCH in the LCP procedure.

5. A terminal device according to any one of claims 1 to 4, wherein the control unit is configured to: determine the priority for the LCH based on the second information when the LCH has predetermined data; and determine the priority for the LCH based on the first information when the LCH does not have the predetermined data.

6. The terminal device according to claim 5, wherein the predetermined data is associated with the predetermined timer, and the predetermined data is data indicating that the remaining time of the predetermined timer falls below the threshold value for the predetermined timer on a predetermined occasion.

7. The terminal device of claim 6, wherein the predetermined opportunity includes at least one of: when a new transmission is performed; when the LCP procedure is applied; when an Uplink Shared Channel (UL-SCH) resource becomes available for a new transmission; and when a Physical Uplink Shared Channel (PUSCH) including data of the LCH is transmitted.

8. A terminal device according to any one of claims 1 to 7, wherein the predetermined timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance, which is a discard timer used in data discard processing based on Protocol Data Unit Set Importance (PSI).

9. The terminal device according to any one of claims 1 to 8, wherein the receiving unit is configured to receive, from the base station device, an RRC message including information for setting the threshold value for the predetermined timer for the LCH.

10. A method for a terminal device (10), comprising: receiving a Radio Resource Control (RRC) message from a base station device, the Radio Resource Control (RRC) message including first information for setting a priority for a logical channel (LCH); and performing a Logical Channel Prioritization (LCP) procedure, wherein performing the LCP procedure comprises determining the priority for the LCH based on either the first information or second information for setting the priority for the LCH according to a threshold value for a predetermined timer.

11. The method of claim 10, wherein determining the priority for the LCH includes: determining the priority for the LCH based on either the first information or the second information when the RRC message includes the second information; and determining the priority for the LCH based on the first information when the RRC message does not include the second information.

12. The method according to claim 10 or 11, further comprising receiving an RRC message from the base station device, the RRC message including third information, the third information including at least one of information for setting a prioritized bit rate (PBR) for the LCH and information for setting a bucket size duration (BUCKETSIZEDURATION, BSD) for the LCH, the method further comprising determining at least one of the PBR and the BSD for the LCH based on either the third information or fourth information in accordance with the threshold value for the predetermined timer, and the fourth information including at least one of information for setting the PBR for the LCH and information for setting the BSD for the LCH.

13. The method according to any one of claims 10 to 12, further comprising allocating resources to the LCH based on the determined priority for the LCH in the LCP procedure.

14. A method according to any one of claims 10 to 13, wherein determining the priority for the LCH includes: determining the priority for the LCH based on the second information if the LCH has predetermined data; and determining the priority for the LCH based on the first information if the LCH does not have the predetermined data.

15. The method of claim 14, wherein the predetermined data is associated with the predetermined timer, and the predetermined data is data indicating that the remaining time of the predetermined timer falls below the threshold value for the predetermined timer on a predetermined occasion.

16. The method of claim 15, wherein the predetermined occasions include at least one of: when performing a new transmission; when applying the LCP procedure; when Uplink Shared Channel (UL-SCH) resources become available for a new transmission; and when transmitting a Physical Uplink Shared Channel (PUSCH) containing data of the LCH.

17. The method according to any one of claims 10 to 16, wherein the predetermined timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance, which is a discard timer used in a data discard process based on Protocol Data Unit Set Importance (PSI).

18. The method according to any one of claims 10 to 17, further comprising receiving an RRC message from the base station device including information for setting the threshold for the predetermined timer for the LCH.

19. A base station device (20) comprising: a transmitting unit (221) configured to transmit, to a terminal device (10), a Radio Resource Control (RRC) message including first information for setting a priority for a logical channel (LCH); and in a Logical Channel Prioritization (LCP) procedure, the priority for the LCH is determined based on either the first information or second information for setting the priority for the LCH in accordance with a threshold value for a predetermined timer.

20. The base station device according to claim 19, wherein, if the RRC message includes the second information, the priority for the LCH is determined based on either the first information or the second information, and if the RRC message does not include the second information, the priority for the LCH is determined based on the first information.

21. The base station device according to claim 19 or 20, wherein the transmitting unit is configured to transmit an RRC message including third information to the terminal device, the third information including at least one of information for setting a prioritized bit rate (PBR) for the LCH and information for setting a bucket size duration (BUCKETSIZEDURATION, BSD) for the LCH, and at least one of the PBR and the BSD for the LCH is determined based on either the third information or fourth information in accordance with the threshold value for the predetermined timer, and the fourth information including at least one of information for setting the PBR for the LCH and information for setting the BSD for the LCH.

22. The base station device according to any one of claims 19 to 21, wherein in the LCP procedure, resources are allocated to the LCH based on the determined priority for the LCH.

23. A base station device according to any one of claims 19 to 22, wherein, when the LCH has predetermined data, the priority for the LCH is determined based on the second information, and when the LCH does not have the predetermined data, the priority for the LCH is determined based on the first information.

24. The base station device according to claim 23, wherein the predetermined data is associated with the predetermined timer, and the predetermined data is data when the remaining time of the predetermined timer falls below the threshold value for the predetermined timer on a predetermined occasion.

25. The base station device of claim 24, wherein the predetermined opportunity includes at least one of: when a new transmission is performed; when the LCP procedure is applied; when an Uplink Shared Channel (UL-SCH) resource becomes available for a new transmission; and when a Physical Uplink Shared Channel (PUSCH) including data of the LCH is transmitted.

26. The base station device according to any one of claims 19 to 25, wherein the predetermined timer is a Packet Data Convergence Protocol (PDCP) discard timer, or a DiscardTimerForLowImportance, which is a discard timer used in data discard processing based on Protocol Data Unit Set Importance (PSI).

27. The base station device according to any one of claims 19 to 26, wherein the transmitter is configured to transmit to the terminal device an RRC message including information for setting the threshold value for the predetermined timer for the LCH.

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