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

Abstract

A terminal device (10) generates either a first delay status reporting (DSR) medium access control control element (MAC CE) or a second DSR MAC CE, on the basis of the presence of suspended DSR and a remaining time threshold value for a logical channel group (LCG), the remaining time threshold value being included in a radio resource control (RRC) message.

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. 2024-107938, filed on July 4, 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 V18.1.0 (2024-03)3GPP TS 38.331 V18.1.0 (2024-03)3GPP TS 26.522 V0.1.0 (2023-05)

[0006] Non-Patent Document 1 describes the technical specifications of Delay Status Reporting (DSR). DSR is used by a terminal device to provide a base station device with the delay status (or delay information) of a Logical Channel Group (LCG). DSR includes, as the delay status, information on the remaining time and information on the buffer size.

[0007] XR is operated under various requirements, including the requirement of low latency. Taking this into consideration, enhancements to DSR have been proposed. However, Non-Patent Document 1 does not describe the procedures when DSR is extended. Therefore, the inventors have discovered a problem that a terminal device may not be able to properly transmit the extended DSR. Note that the above problem may also occur in ordinary terminal devices other than those implementing XR.

[0008] The present disclosure provides a technique that enables a terminal device to appropriately transmit an extended DSR.

[0009] A terminal device according to the present disclosure includes a receiver that receives a Radio Resource Control (RRC) message, and a controller that triggers a Delay Status Report (DSR) based on information included in the RRC message indicating a first remaining time threshold used to trigger the DSR. The controller reserves the triggered DSR, and generates either a first DSR Medium Access Control Element (MAC CE) or a second DSR MAC CE different from the first DSR MAC CE based on the existence of the reserved DSR and a second remaining time threshold for a Logical Channel Group (LCG) included in the RRC message.

[0010] A method for a terminal device according to the present disclosure includes receiving a Radio Resource Control (RRC) message and triggering a Delay Status Report (DSR) based on information included in the RRC message indicating a first remaining time threshold used for triggering the DSR. The method further includes suspending the triggered DSR and generating either a first DSR Medium Access Control Element (MAC CE) or a second DSR MAC CE different from the first DSR MAC CE based on the existence of the suspended DSR and a second remaining time threshold for a Logical Channel Group (LCG) included in the RRC message.

[0011] A base station apparatus according to the present disclosure includes a transmitter that transmits a Radio Resource Control (RRC) message, and a receiver that receives a Delay Status Report (DSR) from a terminal apparatus, the DSR being triggered based on information included in the RRC message indicating a first remaining time threshold used to trigger the DSR. The triggered DSR is suspended in the terminal apparatus. The receiver receives from the terminal apparatus either a first DSR Medium Access Control Element (MAC CE) or a second DSR MAC CE different from the first DSR MAC CE, the first DSR MAC CE being generated based on the presence of the suspended DSR and a second remaining time threshold for a Logical Channel Group (LCG) included in the RRC message.

[0012] According to the above configuration, the terminal device can appropriately transmit the extended DSR based on the conditions. 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). FIG. 12 is a diagram showing an example of an additional BSR table (i.e., a second table); FIG. 13 is a diagram showing the configuration of a refined long BSR; FIG. 14 is a sequence diagram showing the processing flow of the terminal device 10 and the base station device 20; FIG. 15 is a diagram showing the configuration of DSR (Delay Status Reporting); FIG. 16 is a sequence diagram showing the processing flow of the terminal device 10 and the base station device 20; FIG. 19 is a sequence diagram showing the processing flow of terminal device 10; FIG. 20 is a diagram showing an example of the configuration of a second DSR; FIG. 21 is a diagram showing an example of the configuration of a second DSR; FIG. 22 is a diagram explaining an example of information included in the second DSR; FIG. 23 is a diagram explaining an example of information included in the second DSR; FIG. 24 is a diagram showing an example of a DSR including second information (i.e., additional information); FIG. 25 is a diagram explaining an example of information included in the first DSR; and FIG. 26 is a diagram explaining an example of information included in the first DSR.

[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 Logical Channel Prioritization (LCP) The terminal device 10 generates a Medium Access Control Protocol Data Unit (MAC PDU) 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 in accordance with the LCP. The LCP 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 LCP 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. In the following description, the expression "the value of the parameter priority is relatively small" may be replaced with the expression "the LCH priority is relatively high." The expression "the value of the parameter priority is relatively large" may be replaced with the expression "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, 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. 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 LCP, 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. 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 LCH 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] In addition, with respect to a BSR triggered by the expiration of the retxBSR-Timer, the terminal device 10 may consider that the LCH that triggered the BSR is the LCH with the highest LCH priority that has data available for transmission at the time the BSR was triggered.

[0108] 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.

[0109] 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.

[0110] 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."

[0111] 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.

[0112] 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.

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] 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.

[0118] 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.

[0119] 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."

[0120] 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.

[0121] 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.

[0122] 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.

[0123] The base station device 20 may transmit an RRC message including parameters for the second table 1200 to the terminal device 10. The above parameters may be included in a MAC-CellGroupConfig IE, which is an example of an RRC information element (IE). For example, the above parameters may be additionalBS-TableAllowed included in the MAC-CellGroupConfig IE.

[0124] The additionalBS-TableAllowed may be "information indicating whether the terminal device 10 is allowed to use the second table 1200 for the LCG." For example, the additionalBS-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.

[0125] As shown in FIG. 13, the refined long BSR includes an LCG field 1310, a BT field 1320, and a buffer size field 1330.

[0126] 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.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] Like the short BSR, the long BSR may include a truncated format and an extended format.

[0132] The BSR may also include a Pre-emptive BSR format and an Extended Pre-emptive BSR format, which are used in the IAB-MT.

[0133] In the case of regular BSR and periodic BSR, a MAC entity for which the 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) long BSRs for all LCGs that have available data. (c2) Otherwise: The terminal device 10 transmits (or reports) extended long BSRs for all LCGs that have available data. (c1) Otherwise: The terminal device 10 transmits (or reports) extended short BSRs.

[0134] In addition, for regular BSR and periodic BSR, a MAC entity for which the logicalChannelGroup-IABExt IE is not configured 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 additionalBS-TableAllowed is configured, the amount of available UL 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, if one LCG has available data, and additionalBS-TableAllowed is set, and when a MAC PDU including a BSR is constructed, the amount of available UL data for transmission is greater than the largest buffer size indicated by the second table 1200: The terminal device 10 transmits (or reports) a long BSR. (d2) Otherwise: The terminal device 10 transmits (or reports) a short BSR.

[0135] 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 Refined Long BSR

[0136] For example, in the case of a padding BSR, a MAC entity in which the logicalChannelGroup-IABExt IE is not set by a higher layer may select a BSR format as follows: (e1) If the number of padding bits is equal to or greater than the size of the short BSR plus its subheader and smaller than the size of the long BSR plus its subheader: (e2) If two or more LCGs have available data for transmission when the BSR is constructed: (e3) If the number of padding bits is equal to the size of the short BSR plus its subheader: The terminal device 10 transmits (or reports) a short Truncated BSR for the LCG containing the LCH with the highest LCH priority among the LCHs with available data for transmission. (e3) Otherwise: The terminal device 10 transmits (or reports) a Long Truncated BSR for the LCG including the LCH with available data for transmission in descending order of the LCH with the highest LCH priority, regardless of whether the LCH has available data for transmission or not. Note that if the LCH priorities are the same, the terminal device 10 transmits (or reports) a Long Truncated BSR in ascending order of the LCG ID. (e2) Otherwise: The terminal device 10 transmits (or reports) a Short BSR. (e1) Otherwise, if, for at least one LCG for which additionalBS-TableAllowed is set, the amount of UL data available for transmission is within the range of the buffer size indicated by the second table 1200, and the number of padding bits is equal to or greater than the size of the refined long BSR plus its subheader: the terminal device 10 transmits (or reports) a refined long BSR for all LCGs that have data available for transmission.(e1) Otherwise, if the number of padding bits is equal to or greater than the size of the long BSR plus its subheader: The terminal device 10 transmits (or reports) a long BSR for all LCGs that have data available for transmission.

[0137] For example, in the case of a padding BSR, a MAC entity in which the logicalChannelGroup-IABExt IE is set by a higher layer may select a BSR format as follows: (f1) If the number of padding bits is equal to or greater than the size of an Extended Short BSR plus its subheader and less than the size of an Extended Long BSR plus its subheader: (f2) If two or more LCGs have available data for transmission when the BSR is constructed: (f3) If the number of padding bits is less than the size of an Extended Long Truncated BSR with a buffer size field set to zero plus its subheader: The terminal device 10 transmits (or reports) an Extended Short Truncated BSR for an LCG that includes an LCH with the highest LCH priority among the LCHs that have available data for transmission. (f3) Otherwise: The terminal device 10 transmits (or reports) Extended Long Truncated BSRs for LCGs including LCHs with available data for transmission, in descending order of the LCHs with the highest LCH priority, regardless of whether they have available data for transmission or not. Note that if the priorities are the same, the terminal device 10 transmits (or reports) Extended Long Truncated BSRs in ascending order of LCG ID. (f2) Otherwise: The terminal device 10 transmits (or reports) Extended Short BSRs. (f1) Otherwise, if the number of padding bits is equal to or greater than the size of the Extended Long BSR plus its subheader: The terminal device 10 transmits (or reports) Extended Long BSRs for all LCGs with available data for transmission.

[0138] As described above, the terminal device 10 may select the BSR format based on the number of padding bits and the LCH priority.

[0139] The procedure by which the terminal device 10 transmits a BSR MAC CE to the base station device 20 will be described below.

[0140] 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.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] 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). Based on receiving a PDCP SDU from a higher layer, the PDCP entity of the terminal device 10 may start the PDCP discard timer associated with the PDCP SDU.

[0145] 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 a remainingTimeThreshold. The remainingTimeThreshold may be configured for each LCG. Specifically, the remainingTimeThreshold may be configured in association with an LCG ID. The remainingTimeThreshold may be a threshold used for the remaining time to trigger DSR for an LCH belonging to a certain LCG.

[0146] The MAC entity of the terminal device 10 may trigger DSR as follows when an LCG is configured for DSR. The MAC entity may trigger DSR for each LCH belonging to the LCG when both of the following (g1) and (g2) are met: (g1) The shortest remaining time of the running PDCP discard timer of all data (i.e., PDCP SDUs) buffered in the LCH or LCG that has not been transmitted in any MAC PDU and / or not reported as data amount in a DSR MAC CE is less than the remainingTimeThreshold configured for the LCH or LCG. (g2) There is no pending DSR for the LCH or LCG.

[0147] 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.

[0148] 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. If there is at least one pending DSR, the MAC entity may trigger an SR if UL-SCH resources are not available for the new transmission or if the UL-SCH resources cannot accommodate the DSR MAC CE and its subheader, and if there is no pending SR (i.e., scheduling request) already triggered by a DSR procedure for the same LCH. If there is at least one pending DSR, the MAC entity may trigger an SR if there is no pending SR already triggered by a DSR procedure for the same LCH and if a CG is configured for the MAC entity.

[0149] 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."

[0150] For 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:

[0151] The PDCP entity may calculate the delay-critical PDCP data amount by taking into account the following (h1) to (h5): (h1) delay-critical PDCP SDUs for which no PDCP data PDUs have been constructed, (h2) PDCP data PDUs that include delay-critical PDCP SDUs and have not been transmitted to a lower layer, (h3) PDCP control PDUs, (h4) PDCP SDUs retransmitted using AM DRBs, and (h5) PDCP data PDUs retransmitted using AM DRBs.

[0152] 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 for at least one PDCP SDU is less than remainingTimeThreshold. Note that an AM DRB is a data radio bearer that uses RLC AM (Acknowledge Mode).

[0153] The RLC entity may calculate the delay-critical RLC data amount by considering the following (i1) to (i3): (i1) delay-critical RLC SDUs or delay-critical RLC SDU segments not included in an RLC data PDU, (i2) RLC data PDUs that contain delay-critical RLC SDUs or delay-critical RLC SDU segments and are pending for initial transmission, and (i3) RLC data PDUs that are pending for retransmission in RLC AM.

[0154] A delay-critical RLC SDU is an RLC SDU that corresponds to a PDCP PDU that is indicated as "delay-critical" by PDCP.

[0155] Therefore, the PDCP entity may indicate to the RLC entity the PDUs containing PDCP SDUs that are less than the remainingTimeThreshold, and the PDUs may be considered as delay-critical RLC SDUs, and the PDUs containing the delay-critical RLC SDUs may be included in the amount of delay-critical UL data.

[0156] 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.

[0157] 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 LCGi (i.e., remaining time and buffer size, 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 delay information for LCGi is present in the delay information field 1520. That is, this may indicate that delay information for LCGi is reported. If the value of LCGi is 0, this may indicate that delay information for LCGi is not present in the delay information field 1520. That is, this may indicate that delay information for LCGi is not reported.

[0158] 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 set to 1 and the bit corresponding to LCG2 is set to 1. Therefore, the delay information field 1520 includes a set of fields 1530 corresponding to LCG1. The set of fields 1530 includes a first field 1531 and a second field 1532. Furthermore, the delay information field 1520 includes a set of fields 1540 corresponding to LCG2. The set of fields 1540 includes a first field 1541 and a second field 1542. Note that it is assumed that in the LCG field 1510, the bit corresponding to LCG0 is set to 0. Therefore, the delay information field 1520 does not include a set of fields corresponding to LCG0.

[0159] The set of fields 1530 corresponding to LCG1 will be described below. The first field 1531 includes at least a first portion 1531a and a second portion 1531b. Note that "R" in the first field 1531 is a reserved bit.

[0160] The first part 1531a consists of one bit. The first part 1531a is present only if additionalBS-TableAllowed is set for the corresponding LCG and the buffer size indicated by the corresponding second field 1532 is not zero. Otherwise, the first part 1531a may be "reserved" or set to 0. If the first part 1531a is present, the first part 1531a 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 part 1531a may indicate whether the second field 1532 was set in the first table 1100 or the second table 1200. If the value of the first part 1531a is 0, this may indicate that the first table 1100 was used to set the second field 1532. If the value of the first portion 1531 a is 1, this may indicate that the second table 1200 was used to set the second field 1532 .

[0161] The second part 1531b is composed of 6 bits. The second part 1531b represents the remaining time for the data corresponding to LCG1. More specifically, the second part 1531b may represent the shortest remaining time of the running 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 not transmitted in any MAC PDU.

[0162] The second field 1532 consists of 8 bits. The second field 1532 indicates the total amount of delay-critical UL data for LCG1. If additionalBS-TableAllowed is set and the buffer size (i.e., the total amount of delay-critical UL data) is within the range of the buffer size indicated by the second table 1200, the MAC entity sets the second field 1532 using the second table 1200. Otherwise, the MAC entity sets the second field 1532 using the first table 1100.

[0163] The set of fields 1540 corresponding to LCG2 has the same configuration as the set of fields 1530 corresponding to LCG1. The first field 1541 has the same configuration as the first field 1531. The first field 1541 includes at least a first portion 1541a and a second portion 1541b. For example, the first portion 1541a indicates whether the second field 1542 is set in the first table 1100 or the second table 1200. For example, the second portion 1541b represents the remaining time described above for the data corresponding to LCG2. The second field 1542 has the same configuration as the second field 1532. For example, the second field 1542 indicates the total amount of delay-critical UL data for LCG2.

[0164] 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.

[0165] The procedure by which the terminal device 10 transmits a DSR MAC CE to the base station device 20 will be described below.

[0166] 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.

[0167] The control unit 110 of the terminal device 10 triggers DSR based on parameters included in the RRC message. For example, if an LCG is configured for DSR, the control unit 110 triggers DSR for each LCH belonging to the LCG when both of (g1) and (g2) above are satisfied. The communication unit 120 of the terminal device 10 transmits DSR (S1602).

[0168] 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 the 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.

[0169] 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.

[0170] Non-Patent Document 3 defines fields included in the RTP Header Extension. The importance of a PDU set (i.e., PSI) 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.

[0171] 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."

[0172] 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."

[0173] 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 set to be shorter than the first discard timer.

[0174] The second discard timer is started in place of the first discard timer when PSI-based discard processing is activated.

[0175] 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 starts the first discard timer associated with the PDCP SDU.

[0176] The base station device 20 may transmit a MAC CE to the terminal device 10 to indicate whether the PSI-based discard process is enabled or disabled.

[0177] 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.

[0178] When the terminal device 10 receives the MAC CE shown in FIG. 17 for a DRB for which PSI-based discard processing is configured, the MAC entity of the terminal device 10 may indicate to upper layers whether the PSI-based discard processing is enabled or disabled for each DRB.

[0179] In addition, a DRB for which the PSI-based discard process is configured may be a DRB for which a second discard timer is configured and which is configured in an RLC entity associated with the MAC entity.

[0180] 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.

[0181] 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.

[0182] 1.11. DSR Enhancement XR operates under various requirements, including low latency requirements. Taking this into consideration, the terminal device 10 may transmit an enhanced DSR. Hereinafter, the existing DSR shown in FIG. 15 is referred to as a "first DSR." In contrast, in this embodiment, the terminal device 10 may transmit (or generate) a DSR different from the first DSR. Hereinafter, this DSR may be referred to as a "second DSR" or an "enhanced DSR." The second DSR may include information not included in the first DSR. In one example, the second DSR may include the information included in the first DSR described in FIG. 15 and additional information.

[0183] According to the above configuration, the terminal device 10 transmits (or generates) a first DSR and a second DSR. However, Non-Patent Document 1 describes only the procedure related to the first DSR. Therefore, when a DSR is triggered, there is a problem as to whether the terminal device 10 generates the first DSR or the second DSR. For example, when a DSR is triggered, there is a possibility that the terminal device 10 will not be able to properly transmit the second DSR.

[0184] Regarding the above problem, when a DSR is triggered for a certain LCH or LCG (for example, when there is at least one DSR pending), the control unit 110 of the terminal device 10 may transmit (or generate) a second DSR based on at least one of the following conditions (j1) to (j3): (j1) Conditions related to uplink resources (j2) Conditions related to first setting information for the second DSR (j3) Conditions related to uplink data

[0185] Below, the details of each of the conditions (j1) to (j3) will be explained.

[0186] 1.11.1 Condition (j1) Condition (j1) may be a condition that the uplink resource is capable of accommodating the second DSR as a result of the LCP. More specifically, condition (j1) may be a condition that there is an available UL-SCH resource for a new transmission, and that the UL-SCH resource is capable of accommodating the second DSR and its subheader as a result of the LCP. If condition (j1) is satisfied, the control unit 110 may transmit (or generate) the second DSR.

[0187] 1.11.2. Condition (j2) Condition (j2) may be a condition that first setting information for the second DSR is set. If condition (j2) is satisfied, the control unit 110 may transmit (or generate) the second DSR. The base station device 20 may transmit the first setting information to the terminal device 10. That is, the terminal device 10 may receive the first setting information from the base station device 20.

[0188] The base station device 20 may include the first setting information in the RRC message transmitted in S1601 of Fig. 16. Note that the base station device 20 may transmit the first setting information to the terminal device 10 using at least one of the RRC message, the MAC CE, and the DCI.

[0189] The first configuration information may be configured for a cell group. The first configuration information may be configured in an IE related to a MAC cell group included in the RRC message. An example of such an IE is a MAC-CellGroupConfig IE. The first configuration information may be configured for an LCH. The first configuration information may be configured in an IE related to an LCH included in the RRC message. An example of such an IE is a LogicalChannelConfig IE. The first configuration information may be configured for an LCG. The first configuration information may be configured in an IE related to an LCG included in the RRC message. An example of such an IE is an LCG-DSR-Config IE.

[0190] The first setting information may be information that explicitly indicates that the terminal device 10 is allowed to report the second DSR. For example, the first setting information may be information indicating whether or not the terminal device 10 is allowed to report the second DSR. "Information indicating whether or not the terminal device 10 is allowed to report the second DSR" may be a flag indicating that "the terminal device 10 is allowed to report the second DSR" or "the terminal device 10 is not allowed to report the second DSR". For example, the first setting information may be a flag indicating that "the terminal device 10 is allowed to report the second DSR" or "the terminal device 10 is not allowed to report the second DSR" for a cell group, an LCH, or an LCG.

[0191] For example, the first configuration information may be a bit string (i.e., a bitmap) corresponding to an LCH or an LCG. Each bit of the bit string may correspond to each LCH or LCG. For example, in the case of an n-bit string, the bit string from the most significant bit to the least significant bit may correspond to LCH or LCG ID 0, ..., LCH or LCG ID n-1, respectively. If the value of the bit is 1, this may indicate that the terminal device 10 is permitted to include delay information related to the LCG corresponding to the bit (or the LCG to which the LCH belongs) in the second DSR. If the value of the bit is 0, this may indicate that the terminal device 10 is not permitted to include delay information related to the LCG corresponding to the bit (or the LCG to which the LCH belongs) in the second DSR.

[0192] For example, the first setting information may be a parameter related to DSR. The first setting information may be a remaining time threshold different from remainingTimeThreshold. Hereinafter, remainingTimeThreshold is referred to as a "first remaining time threshold." The remaining time threshold different from remainingTimeThreshold is referred to as a "second remaining time threshold." The second remaining time threshold may be greater than the first remaining time threshold. The second remaining time threshold may be a threshold for the first discard timer. The second remaining time threshold may be a threshold for the second discard timer. Note that the second remaining time threshold may not trigger DSR (i.e., the first DSR and the second DSR).

[0193] For example, the first setting information may be information regarding the importance of data, information regarding the importance of a PDU set, or information regarding the PSI.

[0194] 1.11.3 Condition (j3) Condition (j3) may be a condition that at least one LCH or LCG has predetermined uplink data. If condition (j3) is satisfied, the control unit 110 may transmit (or generate) a second DSR.

[0195] The above "at least one LCH or LCG" may be an LCH or LCG for which the first configuration information is configured. In another example, the above "at least one LCH or LCG" may be an LCH or LCG for which the first configuration information indicates that reporting the second DSR is permitted.

[0196] The above-mentioned "predetermined uplink data" may be uplink data that satisfies the following specific condition. For example, the specific condition may be a condition based on the remaining time for data buffered in at least one LCH or LCG. For example, the specific condition may be that the remaining time of a PDCP discard timer (first discard timer or second discard timer) for data buffered in an LCH or LCG is below or above a first remaining time threshold. In another example, the specific condition may be that the remaining time of a PDCP discard timer (first discard timer or second discard timer) for data buffered in an LCH or LCG is below or above a second remaining time threshold. In yet another example, the specific condition may be a combination of the PDCP discard timer (first discard timer or second discard timer) and the first and second remaining time thresholds. For example, the specific condition may be that the LCH or LCG has data for which the time remaining until the expiration of a running PDCP discard timer (first discard timer or second discard timer) is above a first remaining time threshold and below a second remaining time threshold.

[0197] The specific condition may be that at least one LCH or LCG has data that is not delay-critical UL data. That is, the specific condition may be that the LCH or LCG has non-delay-critical UL data. "Having non-delay-critical UL data" may mean that the amount of data associated with the LCH or LCG, excluding the delay-critical UL data, is not zero or is equal to or greater than a predetermined data amount threshold.

[0198] The specific condition may be that at least one LCH or LCG has data with a predetermined importance. The specific condition may be that at least one LCH or LCG has data with high importance. For example, the specific condition may be that at least one LCH or LCG has data with a predetermined importance or higher. The specific condition may be that at least one LCH or LCG has data with low importance. For example, the specific condition may be that at least one LCH or LCG has data with a predetermined importance or lower. The importance may be a value related to the PSI. The specific condition described above may be set by the first setting information. For example, parameters related to the specific condition (e.g., the second remaining time threshold and / or information about the importance) may be set by the first setting information.

[0199] 1.11.4. Combination of Conditions (j1) to (j3) When a DSR is triggered for a certain LCH or LCG, the control unit 110 may transmit (or generate) a second DSR based on a combination of two or more of conditions (j1) to (j3). For example, when conditions (j1) and (j2) are satisfied, the control unit 110 may transmit (or generate) the second DSR. When conditions (j1) and (j3) are satisfied, the control unit 110 may transmit (or generate) the second DSR. When conditions (j2) and (j3) are satisfied, the control unit 110 may transmit (or generate) the second DSR. When all of conditions (j1) to (j3) are satisfied, the control unit 110 may transmit (or generate) the second DSR.

[0200] 1.11.5 Processing Flow of the Terminal Device 10 For example, if a DSR is triggered for a certain LCH or LCG and at least one of the above conditions (j1) to (j3) is satisfied, the control unit 110 may transmit (or generate) a second DSR. On the other hand, if a DSR is triggered for an LCH or LCG and at least one of the above conditions (j1) to (j3) is not satisfied, the control unit 110 may transmit (or generate) a first DSR.

[0201] Specifically, when a DSR is triggered for a certain LCH or LCG based on the above (g1) and (g2) (for example, when there is at least one DSR pending), the control unit 110 may execute the procedure of FIG. 19. The control unit 110 determines whether a predetermined condition is met (S1901). The predetermined condition includes at least one of the above conditions (j1) to (j3). If the predetermined condition is met, the control unit 110 transmits (or generates) a second DSR (S1902).

[0202] On the other hand, if the predetermined condition is not satisfied, the control unit 110 executes a predetermined operation (S1903). The control unit 110 may execute the following process as the predetermined operation. For example, the control unit 110 may transmit (or generate) a first DSR. The control unit 110 may transmit the first DSR based on one or more conditions other than the above conditions (j1) to (j3). For example, the control unit 110 may transmit (or generate) the first DSR when there is an available UL-SCH resource for a new transmission and the UL-SCH resource can accommodate the first DSR and its subheader as a result of the LCP. In another example, the control unit 110 may transmit (or trigger) an SR. For example, the control unit 110 may transmit an SR based on one or more conditions other than the above conditions (j1) to (j3). For example, the control unit 110 may transmit (or trigger) an SR if there are no pending SRs already triggered by a DSR procedure for the same LCH, if the UL-SCH resources are not available for a new transmission or if the UL-SCH resources cannot accommodate the first DSR and its subheader. In another example, the control unit 110 may not perform the transmission of a DSR and an SR based on one or more conditions other than the above conditions (j1) to (j3).

[0203] In yet another example, the control unit 110 may perform the following procedure when there is at least one pending DSR: (k1) If there are UL-SCH resources available for a new transmission, and the UL-SCH resources can accommodate a second DSR and its subheader as a result of an LCP, and a second remaining time threshold is set for at least one LCG, and the remaining time of a running PDCP discard timer (e.g., the first discard timer or the second discard timer) associated with an SDU buffered for the LCG exceeds the first remaining time threshold and falls below the second remaining time threshold: (k2) The control unit 110 transmits (or generates) a second DSR. (k1) If there are UL-SCH resources available for a new transmission and the UL-SCH resources can accommodate the first DSR and its subheader as a result of the LCP: (k2) The control unit 110 transmits (or generates) the first DSR. (k1) If there is no pending SR (Scheduling Request) already triggered by the DSR procedure for the same LCH as this DSR: (k2) The control unit 110 triggers the SR.

[0204] 1.11.6. Configuration of the Second DSR The control unit 110 may include at least one of the following information (l1) to (l6) in the second DSR.

[0205] (l1) LCG Field The second DSR may include an LCG field. The LCG field may have a configuration similar to that of the LCG field 1510 in FIG. 15 . That is, the LCG field may be configured with 8 bits. In the LCG field, the 8 bits may correspond to eight LCGi, respectively. The LCG field may indicate whether delay information for an LCGi is included in the second DSR. For example, in the LCG field, if the value of LCGi is 1, this may indicate that at least one of the pieces of information (l2) to (l6) described below is included in the second DSR for the LCGi. If the value of LCGi is 0, this may indicate that at least one of the pieces of information (l2) to (l6) for the LCGi is not included in the second DSR for the LCGi.

[0206] (12) Information Regarding Buffer Size The second DSR may include information regarding buffer size. For example, the second DSR may include one or more fields regarding buffer size. Hereinafter, the fields will be referred to as "buffer size fields."

[0207] For example, the second DSR may include two or more buffer size fields. For example, the second DSR may always include two or more buffer size fields for LGIi based on the value of LGIi in the LCG field. For example, if the value of LGIi in the LCG field is 1, the second DSR may include two or more buffer size fields corresponding to LGIi. In this configuration, the two or more buffer size fields may include at least a first buffer size field and a second buffer size field. The first buffer size field may indicate the total amount of delay-critical UL data corresponding to LGIi. Alternatively, the first buffer size field may indicate the total amount of data available in LGIi. The second buffer size field may indicate the buffer size of non-delay-critical UL data. For example, the second buffer size field may indicate the amount of data available in LGIi excluding delay-critical UL data.

[0208] The control unit 110 may include two or more buffer size fields for the LCGi in the second DSR based on the first setting information. For example, if the first setting information is set for the LCGi, the control unit 110 may include two or more buffer size fields for the LCGi in the second DSR. If the first setting information is not set for the LCGi, the control unit 110 may include one buffer size field for the LCGi in the second DSR.

[0209] For example, a case will be described in which the first setting information is a bit string corresponding to an LCG. If the value of the bit corresponding to an LCGi is 1, the control unit 110 may include two or more buffer size fields for the LCGi in the second DSR. If the value of the bit corresponding to an LCGi is 0, the control unit 110 may include one buffer size field for the LCGi in the second DSR.

[0210] The buffer size field may indicate an amount of data calculated based on a first time remaining threshold. The buffer size field may indicate an amount of data calculated based on a second time remaining threshold. In another example, if the second DSR includes two or more buffer size fields corresponding to LCGi, the second DSR may include, for LCGi, a buffer size field indicating an amount of data calculated based on the first time remaining threshold and a buffer size field indicating an amount of data calculated based on the second time remaining threshold.

[0211] For example, the buffer size field may indicate an amount of data calculated based on a discard timer (the first discard timer or the second discard timer) and at least one of a first remaining time threshold and a second remaining time threshold.

[0212] For example, the buffer size field may indicate, for data associated with LCG i, an amount of data for which the time remaining until the first discard timer expires is below or above a first remaining time threshold. In another example, the buffer size field may indicate, for data associated with LCG i, an amount of data for which the time remaining until the first discard timer expires is below or above a second remaining time threshold. In another example, the buffer size field may indicate, for data associated with LCG i, an amount of data for which the time remaining until the first discard timer expires is above the first remaining time threshold and below the second remaining time threshold. That is, the buffer size field may indicate an amount of non-delay-critical UL data for which the time remaining until the first discard timer expires is below the second remaining time threshold.

[0213] For example, the buffer size field may indicate an amount of data calculated based on the second discard timer and at least one of the first remaining time threshold and the second remaining time threshold. For example, the buffer size field may indicate an amount of data associated with LCG i for which the time remaining until the second discard timer expires is below or above the first remaining time threshold. In another example, the buffer size field may indicate an amount of data associated with LCG i for which the time remaining until the second discard timer expires is below or above the second remaining time threshold. In another example, the buffer size field may indicate an amount of data associated with LCG i for which the time remaining until the second discard timer expires is above the first remaining time threshold and below the second remaining time threshold.

[0214] In another example, the buffer size field may be the total amount of data available to all LCHs included in a certain LCG.

[0215] If the second DSR includes two or more buffer size fields corresponding to LCGi, the second DSR may include, for LCGi, a buffer size field indicating an amount of data calculated based on a first remaining time threshold, and a buffer size field indicating an amount of data calculated based on the first remaining time threshold and a second remaining time threshold.

[0216] The buffer size field may indicate a total amount of data based on a specific importance level. The specific importance level may be set by the first configuration information. The buffer size field may indicate a total amount of data having an importance level equal to or greater than a specific importance level. That is, the buffer size field may indicate a total amount of data with high importance. The buffer size field may indicate a total amount of data having an importance level equal to or less than a specific importance level. That is, the buffer size field may indicate a total amount of data with low importance. In another example, when the second DSR includes two or more buffer size fields corresponding to LCGi, the second DSR may include, for LCGi, a buffer size field indicating a total amount of data having an importance level equal to or greater than a specific importance level and a buffer size field indicating a total amount of data having an importance level equal to or less than the specific importance level.

[0217] (13) Information Regarding Remaining Time The second DSR may include information regarding remaining time. For example, the second DSR may include one or more fields regarding remaining time. Hereinafter, the fields will be referred to as "remaining time fields."

[0218] For example, the second DSR may include two or more time remaining fields. For example, the second DSR may always include two or more time remaining fields for LGIi based on the value of LGIi in the LCG field. For example, if the value of LGIi is 1 in the LCG field, the second DSR may include two or more time remaining fields corresponding to LGIi.

[0219] The control unit 110 may include two or more remaining time fields for the LCGi in the second DSR based on the first setting information. For example, if the first setting information is set for the LCGi, the control unit 110 may include two or more remaining time fields for the LCGi in the second DSR. If the first setting information is not set for the LCGi, the control unit 110 may include one remaining time field for the LCGi in the second DSR.

[0220] For example, a case will be described in which the first configuration information is a bit string corresponding to an LCG. If the value of the bit corresponding to an LCGi is 1, the control unit 110 may include two or more remaining time fields for the LCGi in the second DSR. If the value of the bit corresponding to an LCGi is 0, the control unit 110 may include one remaining time field for the LCGi in the second DSR.

[0221] The remaining time field may indicate the remaining time of the data corresponding to the information (l2). For example, if the second DSR includes, as the information (l2), a buffer size of delay-critical UL data corresponding to LCGi, the remaining time field may indicate the remaining time for the delay-critical UL data. For example, if the second DSR includes, as the information (l2), a buffer size of non-delay-critical UL data corresponding to LCGi, the remaining time field may indicate the remaining time for the non-delay-critical UL data.

[0222] The time remaining field may indicate the time remaining based on the first discard timer and / or the second discard timer running for data buffered in LCGi, which may be data buffered in LCGi and not transmitted in any MAC PDU (e.g., PDCP SDUs).

[0223] The remaining time field may indicate the shortest remaining time of a running PDCP discard timer (first discard timer or second discard timer) among the data buffered in LCGi. For example, the remaining time field may indicate the shortest remaining time of a running PDCP discard timer (first discard timer or second discard timer) among the delay-critical UL data buffered in LCGi. For example, the remaining time field may indicate the shortest remaining time of a running PDCP discard timer (first discard timer or second discard timer) among the non-delay-critical UL data buffered in LCGi.

[0224] The remaining time field may indicate a remaining time calculated based on the first remaining time threshold and / or the second remaining time threshold. For example, the remaining time field may indicate the shortest remaining time among the data calculated based on the first remaining time threshold and / or the second remaining time threshold. The remaining time field may indicate the longest remaining time among the data calculated based on the first remaining time threshold and / or the second remaining time threshold.

[0225] When the second DSR includes two or more time remaining fields corresponding to LGIi, the second DSR may include, for LGIi, a time remaining field indicating the remaining time of the data calculated based on a first time remaining threshold and a time remaining field indicating the remaining time of the data calculated based on a second time remaining threshold. In another example, the second DSR may include, for LGIi, a time remaining field indicating the remaining time of the data calculated based on the first time remaining threshold and a time remaining field indicating the remaining time of the data calculated based on the first time remaining threshold and the second time remaining threshold.

[0226] The remaining time field may indicate a remaining time calculated based on the time of the first symbol of the initial transmission of the PUSCH including the second DSR. The remaining time field may indicate the shortest remaining time of a running PDCP discard timer (the first discard timer or the second discard timer) at the time of the first symbol of the initial transmission of the PUSCH including the second DSR.

[0227] For example, the remaining time field may indicate the shortest remaining time of a running PDCP discard timer (the first discard timer or the second discard timer) at the time of the first symbol of the initial transmission of the PUSCH including the second DSR among all PDCP SDUs buffered in LCGi and not transmitted in any MAC PDU.

[0228] For example, the remaining time field may indicate the shortest remaining time of a running PDCP discard timer (the first discard timer or the second discard timer) at the time of the first symbol of the initial transmission of the PUSCH including the second DSR among all PDCP SDUs buffered in LCGi, not transmitted in any MAC PDU, and not delay-critical UL data.

[0229] The remaining time field may indicate the remaining time of data based on a specific importance. The specific importance may be set by the first configuration information. The remaining time field may indicate the remaining time of data having an importance equal to or greater than a specific importance. That is, the remaining time field may indicate the remaining time of data with high importance. The remaining time field may indicate the remaining time of data having an importance equal to or less than a specific importance. That is, the remaining time field may indicate the remaining time of data with low importance. In another example, when the second DSR includes two or more remaining time fields corresponding to LCGi, the second DSR may include, with respect to LCGi, a remaining time field indicating the remaining time of data having an importance equal to or greater than a specific importance and a remaining time field indicating the remaining time of data having an importance equal to or less than the specific importance.

[0230] (l4) Information Regarding the Buffer Size Table The second DSR may include information indicating whether the first table 1100 or the second table 1200 was used to set the information (l2). Hereinafter, this information may be referred to as the "BT field." The BT field may have a configuration similar to that of the first portion 1531a of FIG. 15. That is, the BT field may be composed of one bit. The BT field may be present only if the "additionalBS-TableAllowed" field is set for the corresponding LCGi and the buffer size indicated by the corresponding buffer size field is not zero. Otherwise, the BT field may be "reserved" or may be set to 0. If the BT field is present, the BT field may indicate whether the first table 1100 or the second table 1200 was used to indicate the buffer size field. Note that if the second DSR includes two or more buffer size fields for an LCGi, the second DSR may include two or more BT fields for the LCGi. That is, the second DSR may include a BT field for each buffer size field.

[0231] (l5) Information Regarding Pairs of Buffer Size and Time Remaining The second DSR may include information regarding pairs of buffer size and time remaining. For example, the second DSR may include a field indicating that multiple pairs of buffer size and time remaining exist. Hereinafter, this field will be referred to as the "pair information field." The pair information field may include information indicating whether multiple pairs of buffer size and time remaining are reported. For example, the pair information field may be composed of one bit. When the bit value of the pair information field is 1, this may indicate that multiple pairs of buffer size and time remaining are included in the second DSR. That is, when the bit value of the pair information field is 1, this may indicate that multiple pairs of information (l2) and information (l3) are included in the second DSR. When the bit value of the pair information field is 0, this may indicate that one pair of buffer size and time remaining is included in the second DSR. That is, when the value of the bit in the pair information field is 0, this may indicate that one pair of information (l2) and information (l3) is included in the second DSR. In another example, when the value of the bit in the pair information field is 0, this may indicate that a pair of buffer size and remaining time is not included in the second DSR. That is, when the value of the bit in the pair information field is 0, this may indicate that a pair of information (l2) and information (l3) is not included in the second DSR.

[0232] The second DSR may include a pair information field for each LCG. For example, if the value of a bit in the pair information field corresponding to an LCG i is 1, this may indicate that multiple pairs of information (l2) and information (l3) are included in the second DSR for the LCG i. For example, if the value of a bit in the pair information field corresponding to an LCG i is 0, this may indicate that one pair of information (l2) and information (l3) is included in the second DSR for the LCG i. In another example, if the value of a bit in the pair information field corresponding to an LCG i is 0, this may indicate that no pair of information (l2) and information (l3) is included in the second DSR for the LCG i.

[0233] The pair information field may be set by the first setting information. For example, if the first setting information indicates that "the terminal device 10 is permitted to report the second DSR," the pair information field may indicate that multiple pairs of information (l2) and information (l3) are included in the second DSR.

[0234] For example, if the first configuration information is configured for an LCG, the pair information field may include a pair information field for each LCG. If the first configuration information is configured for an LCGi, the pair information field corresponding to the LCGi may indicate that multiple pairs of information (l2) and information (l3) are included in the second DSR for the LCGi. If the first configuration information is not configured for an LCGi, the pair information field corresponding to the LCGi may indicate that one pair of information (l2) and information (l3) is included in the second DSR for the LCGi, or that no pair of information (l2) and information (l3) is included in the second DSR for the LCGi.

[0235] Note that the pair information field corresponding to an LCG for which the first configuration information is not set may be "reserved" or may be set to 0. In another example, the pair information field corresponding to an LCG for which the first configuration information indicates that the terminal device 10 is not permitted to report the second DSR may be "reserved" or may be set to 0.

[0236] (l6) Information Regarding Importance The second DSR may include information regarding importance. For example, the second DSR may include a field indicating the importance of the corresponding data. Hereinafter, this field will be referred to as the "importance field." For example, the second DSR may include an importance field corresponding to information (l2). If the second DSR includes two or more buffer size fields for LCGi, it may include two or more importance fields corresponding to each of the two or more buffer size fields. The importance field may indicate a PSI value. The importance field may be composed of one bit. The importance field may be a bit indicating whether the importance of the corresponding data is high or low. For example, if the value of a bit in the importance field is 1, this may indicate that the importance of the corresponding data is high (e.g., the PSI value is small). If the value of a bit in the importance field is 0, this may indicate that the importance of the corresponding data is low (e.g., the PSI value is high).

[0237] The control unit 110 may generate the DSR MAC shown in Fig. 20 as the second DSR. The second DSR in this example includes information (l1), information (l2), information (l3), information (l4), and information (l6).

[0238] As shown in FIG. 20, the second DSR includes an LCG field 2010 and a delay information field 2020.

[0239] The LCG field 2010 corresponds to information (l1). The LCG field 2010 has the same configuration as the LCG field 1510 in FIG. 15 . Therefore, a detailed description thereof will be omitted. It is assumed that in the LCG field 2010, the bit corresponding to LCG1 is 1 and the bit corresponding to LCG2 is 1. Therefore, the delay information field 2020 includes a set of fields corresponding to LCG1 and a set of fields corresponding to LCG2. It is assumed that in the LCG field 2010, the bit corresponding to LCG0 is 0. Therefore, the delay information field 2020 does not include a set of fields corresponding to LCG0.

[0240] Furthermore, the control unit 110 includes two pairs of a remaining time field and a buffer size field for LCGi in the second DSR based on the first setting information. Assume that the first setting information is set for LCG1 but not for LCG2. For example, the first setting information is a bit string corresponding to LCG. In this configuration, the value of the bit corresponding to LCG1 is 1, and the value of the bit corresponding to LCG2 is 0.

[0241] Because the value of the bit corresponding to LCG1 in the first configuration information is 1, the delay information field 2020 includes two pairs of a remaining time field and a buffer size field corresponding to LCG1. Specifically, the delay information field 2020 includes a first pair of a remaining time field and a buffer size field corresponding to LCG1, and a second pair of a remaining time field and a buffer size field corresponding to LCG1. Therefore, the delay information field 2020 includes a first set of fields 2030 corresponding to LCG1 and a second set of fields 2040 corresponding to LCG1.

[0242] On the other hand, since the value of the bit corresponding to LCG2 in the first configuration information is 0, the delay information field 2020 includes only the first pair of remaining time and buffer size fields corresponding to LCG2. Therefore, the delay information field 2020 includes a third set of fields 2050 corresponding to LCG2.

[0243] The first set of fields 2030 corresponds to the first pair of remaining time and buffer size fields corresponding to LCG1. The first set of fields 2030 includes fields 2031 and 2032. Field 2031 includes a first portion 2031a, a second portion 2031b, and a third portion 2031c. The first portion 2031a corresponds to information (l4). The first portion 2031a indicates whether the first table 1100 or the second table 1200 was used to set field 2032. The second portion 2031b corresponds to information (l6). The second portion 2031b indicates the importance of the data corresponding to field 2032. The third portion 2031c corresponds to information (l3). The third part 2031c may indicate the shortest remaining time of the first discard timer that is running at the time of the first symbol of the initial PUSCH transmission containing the second DSR among all PDCP SDUs that are not transmitted in any MAC PDU. Field 2032 corresponds to information (l2). Field 2032 may indicate the total amount of delay-critical UL data associated with LCG1.

[0244] The second set of fields 2040 corresponds to a second pair of remaining time and buffer size fields corresponding to LCG1. The second set of fields 2040 includes fields 2041 and 2042. Field 2041 includes a first portion 2041a, a second portion 2041b, and a third portion 2041c. The first portion 2041a corresponds to information (l4). The first portion 2041a indicates whether the first table 1100 or the second table 1200 was used to set field 2042. The second portion 2041b corresponds to information (l6). The second portion 2041b indicates the importance of the data corresponding to field 2042. The third portion 2041c corresponds to information (l3). The third portion 2041c may indicate the remaining time of non-delay-critical UL data. For example, the third portion 2041c may indicate the shortest remaining time of the first discard timer running among the non-delay-critical UL data buffered in LCG1. Field 2042 corresponds to information (l2). Field 2042 may indicate the total amount of non-delay-critical UL data associated with LCG1.

[0245] The third set of fields 2050 corresponds to the first pair of remaining time and buffer size fields corresponding to LCG2. The third set of fields 2050 includes fields 2051 and 2052. Field 2051 includes a first portion 2051a, a second portion 2051b, and a third portion 2051c. Field 2051 has the same structure as field 2031. Similarly, field 2052 has the same structure as field 2032. Therefore, detailed description of fields 2051 and 2052 will be omitted.

[0246] The control unit 110 may generate the DSR MAC shown in Fig. 21 as the second DSR. The second DSR in this example includes information (l1), information (l2), information (l3), information (l4), and information (l5).

[0247] In this example, the control unit 110 includes information Ai in the second DSR. Information Ai corresponds to information (l5) and indicates that the second DSR includes multiple pairs of buffer size and remaining time fields. Therefore, even if the terminal device 10 does not receive the first setting information from the base station device 20, the terminal device 10 can indicate to the base station device 20 whether the second DSR includes multiple pairs of buffer size and remaining time fields.

[0248] As shown in FIG. 21, the second DSR includes an LCG field 2110 and a delay information field 2120 .

[0249] The LCG field 2110 corresponds to information (l1). The LCG field 2110 has the same configuration as the LCG field 2010 in FIG. 20 . Therefore, a detailed description will be omitted. In the LCG field 2110, it is assumed that the bit corresponding to LCG1 is 1 and the bit corresponding to LCG2 is 1. Therefore, the delay information field 2120 includes a set of fields corresponding to LCG1 and a set of fields corresponding to LCG2. It is also assumed that the bit corresponding to LCG0 in the LCG field 2110 is 0. Therefore, the delay information field 2120 does not include a set of fields corresponding to LCG0.

[0250] In this example, delay information field 2120 includes a first pair of time remaining and buffer size fields corresponding to LCG 1 and a second pair of time remaining and buffer size fields corresponding to LCG 1. Furthermore, delay information field 2120 includes only the first pair of time remaining and buffer size fields corresponding to LCG 2. Specifically, delay information field 2120 includes a first set of fields 2130 corresponding to LCG 1, a second set of fields 2140 corresponding to LCG 1, and a third set of fields 2150 corresponding to LCG 2.

[0251] The first set of fields 2130 corresponds to the first pair of the time remaining field and buffer size field corresponding to LCG1. The first set of fields 2130 includes fields 2131 and 2132. Field 2131 includes a first portion 2131a, a second portion 2131b, and a third portion 2131c. The first portion 2131a corresponds to information (l4). The first portion 2131a indicates whether the first table 1100 or the second table 1200 was used to set field 2132. The second portion 2131b includes information A1 corresponding to LCG1. In this example, information A1 consists of one bit and is set to 1. This indicates that multiple pairs of the buffer size field and the time remaining field are included in the second DSR for LCG1. The third portion 2131c corresponds to information (l3). The third part 2131c may indicate the shortest remaining time of the first discard timer that is running at the time of the first symbol of the initial PUSCH transmission containing the second DSR among all PDCP SDUs that are not transmitted in any MAC PDU. Field 2132 corresponds to information (l2). Field 2132 may indicate the total amount of delay-critical UL data for LCG1.

[0252] The second set of fields 2140 corresponds to a second pair of remaining time and buffer size fields corresponding to LCG1. The second set of fields 2140 includes fields 2141 and 2142. Field 2141 includes a first portion 2141a, a second portion 2141b, and a third portion 2141c. The first portion 2141a corresponds to information (l4). The first portion 2141a indicates whether the first table 1100 or the second table 1200 was used to set field 2142. The second portion 2141b may be "reserved" or may be set to 0. The third portion 2141c corresponds to information (l3). The third portion 2141c may indicate the remaining time of non-delay-critical UL data. For example, third portion 2141c may indicate the shortest remaining time on the first discard timer running among the non-delay-critical UL data buffered in LCG1. Field 2142 corresponds to information (l2). Field 2142 may indicate the total amount of non-delay-critical UL data associated with LCG2.

[0253] The third set of fields 2150 corresponds to the first pair of remaining time and buffer size fields corresponding to LCG2. The third set of fields 2150 includes fields 2151 and 2152. Field 2151 includes a first portion 2151a, a second portion 2151b, and a third portion 2151c. Field 2151 has the same structure as field 2131. Similarly, field 2152 has the same structure as field 2132. Therefore, detailed description of fields 2151 and 2152 will be omitted.

[0254] Note that a MAC PDU including a DSR may include identification information for identifying whether the DSR is the first DSR or the second DSR. For example, the first DSR and the second DSR may be identified by a MAC subheader including an LCID or eLCID value (i.e., a codepoint). The MAC subheader of a MAC PDU including a second DSR may include an LCID or eLCID value for identifying the second DSR. The LCID or eLCID value for identifying the second DSR may be different from the LCID or eLCID value for identifying the first DSR.

[0255] The priority of the LCP may be set for the second DSR. The priority of the second DSR may be set to the same as the priority of the first DSR.

[0256] According to the above configuration, when a DSR is triggered for a certain LCH or LCG (for example, when there is at least one DSR pending), the terminal device 10 can appropriately transmit (or generate) a second DSR based on at least one of the conditions (j1) to (j3).

[0257] 2. Second Embodiment When the terminal device 10 is configured to transmit the first DSR and the second DSR, the following problem may arise.

[0258] As described above, the terminal device 10 may trigger a DSR when both of the above conditions (g1) and (g2) are satisfied. In this example, the second DSR includes, as information (l2), a buffer size corresponding to delay-critical UL data and a buffer size corresponding to non-delay-critical UL data. As shown in FIG. 22 , the second DSR is triggered at a certain point in time. In the second DSR, the terminal device 10 reports the buffer size corresponding to data 2201, which is delay-critical UL data, and the buffer size corresponding to data 2202, which is non-delay-critical UL data. Thereafter, the first discard timer corresponding to data 2202 falls below the first remaining time threshold. Non-Patent Document 1 does not describe the procedure for this case. That is, there is a problem regarding how the terminal device 10 operates when the first discard timer corresponding to data 2202, which has already been reported as non-delay-critical UL data by the second DSR, falls below the first remaining time threshold. A similar problem exists regarding whether the terminal device 10 will re-trigger a DSR based on the data 2201 that has already been reported as delay-critical UL data by the second DSR. From the above, after reporting the second DSR, there is a possibility that a DSR will be triggered unnecessarily or that a DSR will not be triggered appropriately.

[0259] In another example, the second DSR includes, as information (l2), a buffer size corresponding to data (e.g., delay-critical UL data) based on a first remaining time threshold and a buffer size corresponding to data based on a second remaining time threshold. As shown in FIG. 23 , the second DSR is triggered at a certain point in time. In the second DSR, the terminal device 10 reports the buffer size corresponding to data 2301 based on the first remaining time threshold and the buffer size corresponding to data 2302 based on the second remaining time threshold. Subsequently, the first discard timer corresponding to data 2302 falls below the first remaining time threshold. Non-Patent Document 1 does not describe the procedure for this case. That is, there is a problem regarding how the terminal device 10 operates when the first discard timer corresponding to data 2302 already reported by the second DSR falls below the first remaining time threshold. Note that a similar problem exists regarding whether the terminal device 10 will re-trigger a DSR based on data 2301 already reported by the second DSR. From the above, after reporting the second DSR, there is a possibility that a DSR may be triggered unnecessarily or may not be triggered appropriately.

[0260] 2.1 DSR Trigger Conditions Below, we will explain aspects 2-1 and 2-2 for solving the above problems.

[0261] 2.1.1 Aspect 2-1 The control unit 110 of the terminal device 10 may be configured not to re-trigger a DSR based on data for which delay information has already been reported as delay-critical UL data by the second DSR. In addition, the control unit 110 may be configured to trigger a DSR when the remaining time corresponding to data for which delay information has been reported as data that is not delay-critical UL data (e.g., non-delay-critical UL data) by the second DSR falls below the first remaining time threshold.

[0262] 22, the control unit 110 does not re-trigger a DSR based on data 2201 whose delay information has already been reported as delay-critical UL data by the second DSR. In addition, the control unit 110 triggers a DSR when the remaining time corresponding to data 2202 whose delay information has already been reported as non-delay-critical UL data by the second DSR falls below the first remaining time threshold.

[0263] 23, the control unit 110 does not re-trigger a DSR based on data 2301 for which delay information has already been reported by the second DSR as data based on the first remaining time threshold. In addition, the control unit 110 triggers a DSR when the remaining time corresponding to data 2302 for which delay information has been reported by the second DSR as data based on the second remaining time threshold falls below the first remaining time threshold.

[0264] More specifically, when an LCG is configured for DSR, the MAC entity of the terminal device 10 may trigger DSR for each LCH belonging to the LCG when both of the following conditions (m1) and (m2) are met: (m1) the shortest remaining time of the running first discard timer of all data (i.e., PDCP SDUs) buffered in the LCH or LCG that has not been transmitted in any MAC PDU and that has not been reported as a data amount in the first DSR or as a delay-critical data amount in the second DSR is less than the first remaining time threshold configured for the LCH or LCG; and (m2) no DSR is pending for the LCH or LCG.

[0265] 2.1.2. Aspect 2-2 The control unit 110 may be configured not to re-trigger a DSR based on data already reported by a second DSR.

[0266] 22, the control unit 110 does not re-trigger a DSR based on data 2201 whose delay information has already been reported as delay-critical UL data by the second DSR. The control unit 110 does not re-trigger a DSR based on data 2202 whose delay information has already been reported as non-delay-critical UL data by the second DSR.

[0267] 23, the control unit 110 does not re-trigger the DSR based on data 2301 for which delay information has already been reported by the second DSR as data based on the first remaining time threshold. The control unit 110 does not re-trigger the DSR based on data 2302 for which delay information has already been reported by the second DSR as data based on the second remaining time threshold.

[0268] More specifically, when an LCG is configured for DSR, the MAC entity of the terminal device 10 may trigger DSR for each LCH belonging to the LCG when both of the following conditions (n1) and (n2) are met: (n1) the shortest remaining time of the running first discard timer of all data (i.e., PDCP SDUs) buffered in the LCH or LCG that has not been transmitted in any MAC PDU and has not been reported as the amount of data in the first DSR or the second DSR is less than the first remaining time threshold configured for the LCH or LCG; and (n2) no DSR is pending for the LCH or LCG.

[0269] According to the above configuration, in a configuration in which the terminal device 10 transmits the first DSR and the second DSR, it is possible to prevent the terminal device 10 from unnecessarily triggering a DSR after reporting the second DSR. Furthermore, it is possible to appropriately trigger a DSR after reporting the second DSR.

[0270] 2.2 Modifications The following modifications may be applied to this embodiment.

[0271] 2.2.1. Variation 2-1 The control unit 110 may trigger a second DSR based on a second remaining time threshold. The second remaining time threshold may be greater than the first remaining time threshold. For example, if a second remaining time threshold is set for at least one LCG or LCH, and the remaining time of a running PDCP discard timer (e.g., the first discard timer or the second discard timer) associated with an SDU buffered for that LCG or LCH falls below the second remaining time threshold, the control unit 110 may trigger a second DSR.

[0272] The control unit 110 may trigger the first DSR and the second DSR separately, i.e., the control unit 110 may trigger the second DSR for a certain LCG or LCH, and then trigger the first DSR for the same LCG or LCH.

[0273] The control unit 110 may cancel the first DSR and / or the second DSR based on the transmission of the second DSR. For example, if a second DSR is transmitted and the second DSR includes delay information (e.g., buffer size and remaining time) for all data associated with the pending first DSR and / or second DSR, the control unit 110 may cancel the first DSR and / or the second DSR. In another example, the control unit 110 may not cancel the second DSR based on the transmission of the first DSR. In yet another example, the control unit 110 may cancel the first DSR based on the transmission of the first DSR.

[0274] An LCP priority may be set for the second DSR, and the priority of the second DSR may be set to a higher priority than the priority of the first DSR.

[0275] 2.2.2. Modification 2-2 The terminal device 10 may extend the first DSR shown in FIG. 15 . That is, the terminal device 10 may add information to the set of fields corresponding to the LCG shown in FIG. 15 . For example, the terminal device 10 may add information to the set of fields 1530 corresponding to LCG1. Hereinafter, the existing information included in the set of fields 1530 in FIG. 15 (i.e., the first part 1531a, the second part 1531b, and the second field 1532) may be collectively referred to as "first information" or "first delay information." Information added to the set of fields 1530 may be referred to as "second information," "second delay information," or "additional information." Therefore, the terminal device 10 may transmit a first DSR including only the first information, or may transmit a first DSR including the first information and the second information, based on a predetermined condition.

[0276] The control unit 110 may add at least one of the above information (l2) to (l6) as second information to a set of fields corresponding to a certain LCG.

[0277] The second information may be added to a set of fields corresponding to one LCG, and not added to a set of fields corresponding to another LCG.

[0278] The second information added to the set of fields corresponding to one LCG may be different from the second information added to the set of fields corresponding to another LCG. For example, the second information added to the set of fields 1530 corresponding to LCG1 may be different from the second information added to the set of fields 1540 corresponding to LCG2. For example, the control unit 110 may add information (l2) to the set of fields 1530 corresponding to LCG1 and information (l3) to the set of fields 1540 corresponding to LCG2. In another example, the control unit 110 may add a pair of a buffer size and a remaining time as the second information. For example, the control unit 110 may add information (l2) to (l4) as the second information.

[0279] For example, the control unit 110 may generate a first DSR shown in Fig. 24. In the example of Fig. 24, it is assumed that in the LCG field 1510, the bit corresponding to LCG1 is 1 and the bit corresponding to LCG2 is 1. It is also assumed that in the LCG field 1510, the bit corresponding to LCG0 is 0.

[0280] As shown in FIG. 24 , the third portion 1531c of the first field 1531 corresponding to LCG1 corresponds to information (l5) and includes the above-mentioned information A1. In this example, the value of information A1 is 1. Therefore, the set of fields 1530 corresponding to LCG1 includes an additional pair of a remaining time field and a buffer size field as the second information. That is, the set of fields 1530 corresponding to LCG1 includes a third field 1533 and a fourth field 1534. The third field 1533 and the fourth field 1534 include information (l2) to (l4) as the second information. For example, the third field 1533 includes a first portion 1533a and a second portion 1533b. The first portion 1533a corresponds to information (l4). That is, the first portion 1533a indicates whether the first table 1100 or the second table 1200 was used to set the fourth field 1534. The second portion 1533b corresponds to information (l3). For example, the second portion 1533b may indicate the remaining time of non-delay-critical UL data. For example, the second portion 1533b may indicate the shortest remaining time of a running first discard timer among the non-delay-critical UL data buffered in LCG1. The fourth field 1534 corresponds to information (l2). The fourth field 1534 may indicate the total amount of non-delay-critical UL data associated with LCG1.

[0281] The third portion 1541c of the first field 1541 corresponding to LCG2 includes information A2 corresponding to LCG2. In this example, the value of information A2 is 0. Therefore, the set of fields 1540 corresponding to LCG2 does not include an additional pair of time remaining and buffer size fields (i.e., the second information).

[0282] The base station device 20 may transmit, to the terminal device 10, second configuration information regarding including (or adding) the second information in the first DSR. The second configuration information may be information indicating that the terminal device 10 is allowed to include the second information in the first DSR. Alternatively, the second configuration information may be information that activates the terminal device 10 to transmit the first DSR including the second information. The base station device 20 may include the second configuration information in the RRC message transmitted in S1601 of FIG. 16. Note that the base station device 20 may transmit the second configuration information to the terminal device 10 using at least one of an RRC message, a MAC CE, and a DCI.

[0283] The second configuration information may be configured for a cell group. The second configuration information may be configured in an IE related to a MAC cell group included in the RRC message. An example of such an IE is a MAC-CellGroupConfig IE. When the second configuration information is configured for a cell group, the control unit 110 may include the second information in the first DSR. The second configuration information may be configured for an LCH. For example, the second configuration information may be configured in an IE related to an LCH included in the RRC message. An example of such an IE is a LogicalChannelConfig IE. When the second configuration information is configured for an LCH, the control unit 110 may include second information corresponding to an LCG to which the LCH belongs in the first DSR. The second configuration information may be configured for an LCG. For example, the second configuration information may be configured in an IE related to an LCG included in the RRC message. An example of such an IE is an LCG-DSR-Config IE. When the second configuration information is configured for an LCG, the control unit 110 may include the second information corresponding to the LCG in the first DSR.

[0284] The second setting information may be information that explicitly indicates that the terminal device 10 is permitted to include the second information in the first DSR. For example, the second setting information may be information that indicates whether the terminal device 10 is permitted to include the second information in the first DSR.

[0285] The "information indicating whether the terminal device 10 is permitted to include the second information in the first DSR" may be a flag indicating that "the terminal device 10 is permitted to include the second information in the first DSR" or "the terminal device 10 is not permitted to include the second information in the first DSR". For example, the second setting information may be a flag indicating that "the terminal device 10 is permitted to include the second information in the first DSR" or "the terminal device 10 is not permitted to include the second information in the first DSR" for a cell group, an LCH, or an LCG.

[0286] For example, the second configuration information may be a bit string (i.e., a bitmap) corresponding to an LCH or an LCG. Each bit of the bit string may correspond to each LCH or LCG. For example, in the case of an n-bit string, the bit string from the most significant bit to the least significant bit may correspond to LCH or LCG ID 0, ..., LCH or LCG ID n-1, respectively. If the value of a bit is 1, this may indicate that the terminal device 10 is permitted to include, in the first DSR, second information corresponding to the LCG (or the LCG to which the LCH belongs) corresponding to the bit. If the value of a bit is 0, this may indicate that the terminal device 10 is not permitted to include, in the first DSR, second information corresponding to the LCG (or the LCG to which the LCH belongs) corresponding to the bit. If it is indicated that second information regarding a certain LCH or LCG is permitted to be included in the first DSR, the control unit 110 may include, in the first DSR, second information corresponding to the LCG or the LCG to which the LCH belongs.

[0287] The second setting information may be information that implicitly indicates that the second information is to be included in the DSR.

[0288] For example, the second setting information may be a parameter related to the DSR. The second setting information may be the above-mentioned second remaining time threshold. As described above, the second remaining time threshold may be set for a cell group, an LCH, or an LCG. The control unit 110 may include the second information in the first DSR based on the second remaining time threshold being set for a cell group, an LCH, or an LCG.

[0289] For example, the second setting information may be a parameter related to the discard process. The second setting information may be a first discard timer or a second discard timer. The control unit 110 may include the second information in the first DSR based on whether pdu-SetDiscard is set. The control unit 110 may include the second information in the first DSR based on whether the second discard timer is set. When the second discard timer is set and the PSI-based discard process is enabled for a certain DRB by the MAC CE shown in FIG. 17 , the control unit 110 may include the second information in the first DSR corresponding to data related to the discard process.

[0290] The second setting information may further include information indicating the type of the second information. For example, the information indicating the type of the second information may be information indicating one or more of the information (l2) to (l6). The information indicating the type of the second information may be information indicating which of the information (l2) to (l6) the terminal device 10 is permitted to include in the first DSR. The terminal device 10 may include one or more of the information (l2) to (l6) in the first DSR based on the information indicating the type of the second information. The information indicating the type of the second information may be set for an LCH or an LCG. For example, the terminal device 10 may include one or more of the information (l2) to (l6) in the first DSR for each LCG based on the information indicating the type of the second information set for each LCG. For example, assume that the information indicating the type of the second information set for each LCG indicates that information (l2) is to be reported to LCG1 and that information (l3) is to be reported to LCG2. In this case, the terminal device 10 may include information (l2) as the second information in the set of fields 1530 corresponding to LCG1, and may include information (l3) as the second information in the set of fields 1540 corresponding to LCG2.

[0291] In the above configuration, the control unit 110 may be configured not to re-trigger the DSR based on data for which delay information has already been reported as delay-critical UL data by the first DSR. In addition, the control unit 110 may be configured not to trigger the DSR when the remaining time corresponding to data for which delay information has been reported as data that is not delay-critical UL data (e.g., non-delay-critical UL data) by the first DSR falls below a first remaining time threshold.

[0292] In the example of FIG. 25 , the terminal device 10 reports, in a first DSR, a buffer size (i.e., first information) corresponding to data 2501, which is delay-critical UL data, and a buffer size (i.e., second information) corresponding to data 2502, which is non-delay-critical UL data. Thereafter, the first discard timer corresponding to data 2502 falls below a first remaining time threshold. In this case, the control unit 110 may trigger a DSR. That is, the control unit 110 may trigger a DSR when the remaining time corresponding to data 2502, whose delay information has been reported as non-delay-critical UL data by the first DSR, falls below the first remaining time threshold. Note that the control unit 110 does not trigger a DSR again based on data 2501 that has already been reported as delay-critical UL data by the first DSR.

[0293] In the example of FIG. 26 , the terminal device 10 reports, in a first DSR, a buffer size (i.e., first information) corresponding to data 2601 based on a first remaining time threshold and a buffer size (i.e., second information) corresponding to data 2602 based on a second remaining time threshold. Thereafter, the first discard timer corresponding to data 2602 falls below the first remaining time threshold. In this case, the control unit 110 may trigger a DSR. That is, the control unit 110 may trigger a DSR when the remaining time corresponding to data 2602 for which delay information has been reported in the first DSR as data based on the second remaining time threshold falls below the first remaining time threshold. Note that the control unit 110 does not trigger a DSR again based on data 2601 for which delay information has already been reported in the first DSR as data based on the first remaining time threshold.

[0294] Specifically, when an LCG is configured for DSR, the MAC entity of the terminal device 10 may trigger DSR for each LCH belonging to the LCG when both of the following conditions (p1) and (p2) are met: (p1) The shortest remaining time of a running first discard timer among all data (i.e., PDCP SDUs) buffered in the LCH or LCG that has not been transmitted in any MAC PDU and has not been reported as a delay-critical data amount in the first DSR is less than the first remaining time threshold configured for the LCH or LCG; and (p2) No DSR is pending for the LCH or LCG.

[0295] According to the above configuration, in a configuration in which the terminal device 10 includes the second information in the first DSR, the terminal device 10 can appropriately trigger the first DSR.

[0296] 3. 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.

[0297] 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).

[0298] 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.

[0299] 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.

[0300] 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.

[0301] 4. 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, a relationship is expressed in which a supplementary note that is dependent on multiple supplementary notes is dependent on another supplementary note that is dependent on multiple supplementary notes. All of the dependency relationships of the supplementary notes expressed below are included in the above embodiments.

[0302] (Appendix A1) A terminal device (10) comprising: a control unit (110) configured to generate either a first Delay Status Report (DSR) or a second DSR different from the first DSR when a DSR is triggered; and a communication unit (120) configured to transmit the generated first DSR or second DSR to a base station device (20), wherein the control unit is configured not to trigger the DSR based on data of delay information reported by the second DSR.

[0303] (Supplementary Note A2) The terminal device according to Supplementary Note A1, wherein the second DSR includes delay information corresponding to delay-critical uplink data, and the control unit is configured not to trigger the DSR based on data for which the delay information is reported as the delay-critical uplink data by the second DSR.

[0304] (Supplementary Note A3) The terminal device described in Supplementary Note A2, wherein the control unit is configured to trigger the DSR when the remaining time of certain data falls below a first remaining time threshold, the second DSR further includes delay information corresponding to non-delay-critical uplink data, and the control unit is configured to trigger the DSR when the remaining time of data for which the delay information is reported as the non-delay-critical uplink data by the second DSR falls below the first remaining time threshold.

[0305] (Supplementary Note A4) The terminal device according to Supplementary Note A1, wherein the control unit is configured to trigger the DSR when the remaining time of certain data falls below a first remaining time threshold, the second DSR includes delay information corresponding to data based on the first remaining time threshold and delay information corresponding to data based on a second remaining time threshold different from the first remaining time threshold, the second remaining time threshold being set to be larger than the first remaining time threshold, and the control unit is configured not to trigger the DSR based on data for which the delay information is reported by the second DSR as data based on the first remaining time threshold.

[0306] (Supplementary Note A5) The terminal device according to Supplementary Note A4, wherein the control unit is configured to trigger the DSR when the remaining time of data for which the delay information is reported by the second DSR as data based on the second remaining time threshold falls below the first remaining time threshold.

[0307] (Supplementary Note A6) A method for a terminal device (10), comprising: when a Delay Status Report (DSR) is triggered, generating either a first DSR or a second DSR different from the first DSR; and transmitting the generated first DSR or second DSR to a base station device (20), wherein the method comprises not triggering the DSR based on data reporting delay information by the second DSR.

[0308] (Appendix A7) A program that causes a processor (101) in a terminal device (10) to execute the following when a Delay Status Report (DSR) is triggered: generating either a first DSR or a second DSR different from the first DSR; and transmitting the generated first DSR or second DSR to a base station device (20), wherein the program further causes the processor to not trigger the DSR based on data of delay information reported by the second DSR.

[0309] (Appendix A8) A non-transitional tangible recording medium having recorded thereon a program that causes a processor (101) in a terminal device (10) to execute the following when a Delay Status Report (DSR) is triggered: generate a first DSR or a second DSR different from the first DSR; and transmit the generated first DSR or second DSR to a base station device (20), wherein the program further causes the processor to not trigger the DSR based on data of delay information reported by the second DSR.

[0310] (Supplementary Note A9) A terminal device (10) comprising: a control unit (110) configured to generate a delay status report (DSR) including first information regarding a delay, and the DSR including the first information and second information regarding the delay; and a communication unit (120) configured to transmit the DSR to a base station device (20), wherein the DSR includes delay information corresponding to delay-critical uplink data as the first information, and the control unit is configured not to trigger the DSR based on data for which the delay information is reported as the delay-critical uplink data by the DSR.

[0311] (Supplementary Note A10) The terminal device according to Supplementary Note A9, wherein the control unit is configured to trigger the DSR when the remaining time of certain data falls below a first remaining time threshold, the DSR further includes delay information corresponding to non-delay critical uplink data as the second information, and the control unit is configured to trigger the DSR when the remaining time of data for which the delay information is reported as the non-delay critical uplink data by the DSR falls below the first remaining time threshold.

[0312] (Supplementary Note A11) The terminal device according to Supplementary Note A9, wherein the control unit is configured to trigger the DSR when the remaining time of certain data falls below a first remaining time threshold, the DSR includes, as the first information, delay information corresponding to data based on the first remaining time threshold, and includes, as the second information, delay information corresponding to data based on a second remaining time threshold different from the first remaining time threshold, the data based on the first remaining time threshold corresponds to the delay-critical uplink data, and the second remaining time threshold is set to be larger than the first remaining time threshold, and the control unit is configured to trigger the DSR when the remaining time of data for which the delay information is reported by the DSR as data based on the second remaining time threshold falls below the first remaining time threshold.

[0313] (Supplementary Note A12) A method for a terminal device (10), comprising: generating a delay status report (DSR) including first information related to a delay, and a DSR including the first information and second information related to the delay; and transmitting the DSR to a base station device (20), wherein the DSR includes delay information corresponding to delay-critical uplink data as the first information; and the method comprises not triggering the DSR based on data for which the delay information is reported as the delay-critical uplink data by the DSR.

[0314] (Supplementary Note A13) A program that causes a processor (101) in a terminal device (10) to execute the following: generating a delay status report (DSR) including first information on delay, and a DSR including the first information and second information on delay; and transmitting the DSR to a base station device (20), wherein the DSR includes delay information corresponding to delay-critical uplink data as the first information; and the program further causes the processor to not trigger the DSR based on data for which the delay information is reported as the delay-critical uplink data by the DSR.

[0315] (Supplementary Note A14) A non-transitive tangible recording medium having recorded thereon a program that causes a processor (101) in a terminal device (10) to execute the following: generate a delay status report (DSR) including first information on delay, and a DSR including the first information and second information on delay; and transmit the DSR to a base station device (20), wherein the DSR includes delay information corresponding to delay-critical uplink data as the first information, and the program further causes the processor to not trigger the DSR based on data for which the delay information is reported as the delay-critical uplink data by the DSR.

[0316] (Supplementary Note B1) A terminal device (10) comprising: a receiving unit (122) that receives a Radio Resource Control (RRC) message; and a control unit (110) that triggers a Delay Status Report (DSR) based on information included in the RRC message indicating a first remaining time threshold used to trigger the DSR, wherein the control unit reserves the triggered DSR, and generates either a first DSR MAC CE (Medium Access Control Element) or a second DSR MAC CE different from the first DSR MAC CE based on the existence of the reserved DSR and a second remaining time threshold for a Logical Channel Group (LCG) included in the RRC message.

[0317] (Supplementary Note B2) The terminal device according to Supplementary Note B1, wherein the control unit generates the first DSR MAC CE when the second remaining time threshold is set for at least one LCG and an Uplink Shared Channel (UL-SCH) resource can accommodate the first DSR MAC CE, and generates the second DSR MAC CE when the second remaining time threshold is not set and the UL-SCH resource can accommodate the second DSR MAC CE.

[0318] (Supplementary Note B3) The terminal device according to Supplementary Note B1 or B2, wherein the control unit triggers the Scheduling Request (SR) if the reserved DSR exists, the UL-SCH resources are not available for new transmission, and there is no pending Scheduling Request (SR) already triggered by the DSR procedure for the same logical channel (Logical Channel, LCH) as the DSR.

[0319] (Supplementary Note B4) The terminal device according to any one of Supplementary Notes B1 to B3, wherein the first DSR MAC CE includes an LCG field indicating that delay information for the LCG exists, and when the LCG field indicates that the delay information for the LCG exists, the first DSR MAC CE includes: a remaining time field indicating the shortest remaining time among data of the LCG based on the second remaining time threshold; a buffer size field indicating the amount of data of the LCG calculated based on the second remaining time threshold; and a field indicating information regarding the pair of the remaining time field and the buffer size field.

[0320] (Supplementary Note B5) The terminal device according to Supplementary Note B4, wherein: the LCG field in the first DSR MAC CE is a first LCG field; the remaining time field in the first DSR MAC CE is a first remaining time field; the buffer size field in the first DSR MAC CE is a first buffer size field; the second DSR MAC CE includes a second LCG field indicating the presence of delay information for the LCG; and if the second LCG field indicates the presence of the delay information for the LCG, the second DSR MAC CE includes: a second remaining time field indicating the shortest remaining time among the data of the LCG based on the first remaining time threshold; and a second buffer size field indicating the amount of data of the LCG calculated based on the first remaining time threshold.

[0321] (Supplementary Note B6) A method for a terminal device (10), comprising: receiving a Radio Resource Control (RRC) message; and triggering a Delay Status Report (DSR) based on information included in the RRC message indicating a first remaining time threshold used to trigger the DSR; the method further comprising: suspending the triggered DSR; and generating either a first DSR MAC CE (Medium Access Control Element) or a second DSR MAC CE different from the first DSR MAC CE based on the existence of the suspended DSR and a second remaining time threshold for a Logical Channel Group (LCG) included in the RRC message.

[0322] (Supplementary Note B7) The method according to Supplementary Note B6, further comprising: generating the first DSR MAC CE when the second remaining time threshold is configured for at least one LCG and an Uplink Shared Channel (UL-SCH) resource can accommodate the first DSR MAC CE; and generating the second DSR MAC CE when the second remaining time threshold is not configured and the UL-SCH resource can accommodate the second DSR MAC CE.

[0323] (Supplementary Note B8) The method according to Supplementary Note B6 or B7, further comprising: triggering the Scheduling Request (SR) if the reserved DSR exists and the UL-SCH resources are not available for new transmissions and there is no pending Scheduling Request (SR) already triggered by the DSR procedure for the same Logical Channel (LCH) as the DSR.

[0324] (Supplementary Note B9) The method of any one of Supplementary Notes B6 to B8, wherein the first DSR MAC CE includes an LCG field indicating that delay information for the LCG exists, and when the LCG field indicates that the delay information for the LCG exists, the first DSR MAC CE includes: a remaining time field indicating the shortest remaining time among the data of the LCG based on the second remaining time threshold; a buffer size field indicating the amount of data of the LCG calculated based on the second remaining time threshold; and a field indicating information about the pair of the remaining time field and the buffer size field.

[0325] (Supplementary Note B10) The method according to Supplementary Note B9, wherein: the LCG field in the first DSR MAC CE is a first LCG field; the remaining time field in the first DSR MAC CE is a first remaining time field; the buffer size field in the first DSR MAC CE is a first buffer size field; the second DSR MAC CE includes a second LCG field indicating the presence of delay information for the LCG; and if the second LCG field indicates the presence of the delay information for the LCG, the second DSR MAC CE includes: a second remaining time field indicating the shortest remaining time of data of the LCG based on the first remaining time threshold; and a second buffer size field indicating the amount of data of the LCG calculated based on the first remaining time threshold.

[0326] (Supplementary Note B11) A base station device (20) comprising: a transmitter (221) that transmits a Radio Resource Control (RRC) message; and a receiver (222) that receives a Delay Status Report (DSR) from a terminal device (10) that has been triggered based on information that is included in the RRC message and indicates a first remaining time threshold used to trigger the DSR, wherein the triggered DSR is reserved in the terminal device, and the receiver receives from the terminal device either a first DSR MAC CE (Medium Access Control Element) or a second DSR MAC CE that is different from the first DSR MAC CE, the first DSR MAC CE being generated based on the presence of the reserved DSR and a second remaining time threshold for a Logical Channel Group (LCG) that is included in the RRC message.

[0327] (Supplementary Note B12) The base station apparatus according to Supplementary Note B11, wherein the receiving unit receives the first DSR MAC CE from the terminal device when the second remaining time threshold is set for at least one LCG and an Uplink Shared Channel (UL-SCH) resource can accommodate the first DSR MAC CE, and receives the second DSR MAC CE from the terminal device when the second remaining time threshold is not set and the UL-SCH resource can accommodate the second DSR MAC CE.

[0328] (Supplementary Note B13) The base station device according to Supplementary Note B11 or B12, wherein the receiving unit receives the SR from the terminal device if the reserved DSR exists in the terminal device, the UL-SCH resources are not available for new transmission, and there is no pending scheduling request (SR) already triggered by the DSR procedure for the same logical channel (Logical Channel, LCH) as the DSR.

[0329] (Supplementary Note B14) The base station device according to any one of Supplementary Notes B11 to B13, wherein the first DSR MAC CE includes an LCG field indicating the presence of delay information for the LCG, and when the LCG field indicates the presence of the delay information for the LCG, the first DSR MAC CE includes: a remaining time field indicating the shortest remaining time among data of the LCG based on the second remaining time threshold; a buffer size field indicating the amount of data of the LCG calculated based on the second remaining time threshold; and a field indicating information on the pair of the remaining time field and the buffer size field.

[0330] (Supplementary Note B15) The base station apparatus according to Supplementary Note B14, wherein the LCG field in the first DSR MAC CE is a first LCG field, the remaining time field in the first DSR MAC CE is a first remaining time field, the buffer size field in the first DSR MAC CE is a first buffer size field, the second DSR MAC CE includes a second LCG field indicating presence of delay information for the LCG, and when the second LCG field indicates the presence of the delay information for the LCG, the second DSR MAC CE includes: a second remaining time field indicating the shortest remaining time among data of the LCG based on the first remaining time threshold, and a second buffer size field indicating an amount of data of the LCG calculated based on the first remaining time threshold.

[0331] 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) that receives a Radio Resource Control (RRC) message; and a control unit (110) that triggers a Delay Status Report (DSR) based on information included in the RRC message indicating a first remaining time threshold used to trigger the DSR, wherein the control unit reserves the triggered DSR, and generates either a first DSR MAC CE (Medium Access Control Element) or a second DSR MAC CE different from the first DSR MAC CE based on the existence of the reserved DSR and a second remaining time threshold for a Logical Channel Group (LCG) included in the RRC message.

2. The terminal device according to claim 1, wherein the control unit generates the first DSR MAC CE when the second remaining time threshold is set for at least one LCG and an Uplink Shared Channel (UL-SCH) resource can accommodate the first DSR MAC CE, and generates the second DSR MAC CE when the second remaining time threshold is not set and the UL-SCH resource can accommodate the second DSR MAC CE.

3. The terminal device according to claim 1 or 2, wherein the control unit triggers the SR when the reserved DSR exists, the UL-SCH resources are not available for new transmission, and there is no pending scheduling request (SR) already triggered by the DSR procedure for the same logical channel (Logical Channel, LCH) as the DSR.

4. The terminal device according to any one of claims 1 to 3, wherein the first DSR MAC CE includes an LCG field indicating that delay information for the LCG exists, and when the LCG field indicates that the delay information for the LCG exists, the first DSR MAC CE includes: a remaining time field indicating the shortest remaining time among the data of the LCG based on the second remaining time threshold; a buffer size field indicating the amount of data of the LCG calculated based on the second remaining time threshold; and a field indicating information regarding the pair of the remaining time field and the buffer size field.

5. The terminal device of claim 4, wherein the LCG field in the first DSR MAC CE is a first LCG field, the remaining time field in the first DSR MAC CE is a first remaining time field, the buffer size field in the first DSR MAC CE is a first buffer size field, the second DSR MAC CE includes a second LCG field indicating the presence of delay information for the LCG, and if the second LCG field indicates the presence of the delay information for the LCG, the second DSR MAC CE includes: a second remaining time field indicating the shortest remaining time among the data of the LCG based on the first remaining time threshold, and a second buffer size field indicating the amount of data of the LCG calculated based on the first remaining time threshold.

6. A method for a terminal device (10), comprising: receiving a Radio Resource Control (RRC) message; and triggering a Delay Status Report (DSR) based on information contained in the RRC message indicating a first remaining time threshold used to trigger the DSR; the method further comprising: reserving the triggered DSR; and generating either a first DSR MAC CE (Medium Access Control Element) or a second DSR MAC CE different from the first DSR MAC CE based on the existence of the reserved DSR and a second remaining time threshold for a Logical Channel Group (LCG) contained in the RRC message.

7. The method of claim 6, further comprising: generating the first DSR MAC CE when the second remaining time threshold is configured for at least one LCG and an Uplink Shared Channel (UL-SCH) resource can accommodate the first DSR MAC CE; and generating the second DSR MAC CE when the second remaining time threshold is not configured and the UL-SCH resource can accommodate the second DSR MAC CE.

8. The method according to claim 6 or 7, further comprising: triggering a Scheduling Request (SR) if the reserved DSR exists, and the UL-SCH resources are not available for new transmissions, and there is no pending Scheduling Request (SR) already triggered by the DSR procedure for the same Logical Channel (LCH) as the DSR.

9. The method of any one of claims 6 to 8, wherein the first DSR MAC CE includes an LCG field indicating that delay information for the LCG exists, and when the LCG field indicates that the delay information for the LCG exists, the first DSR MAC CE includes: a remaining time field indicating the shortest remaining time among the data of the LCG based on the second remaining time threshold; a buffer size field indicating the amount of data of the LCG calculated based on the second remaining time threshold; and a field indicating information regarding the pair of the remaining time field and the buffer size field.

10. The method of claim 9, wherein the LCG field in the first DSR MAC CE is a first LCG field, the remaining time field in the first DSR MAC CE is a first remaining time field, the buffer size field in the first DSR MAC CE is a first buffer size field, the second DSR MAC CE includes a second LCG field indicating the presence of delay information for the LCG, and if the second LCG field indicates the presence of the delay information for the LCG, the second DSR MAC CE includes: a second remaining time field indicating the shortest remaining time of data for the LCG based on the first remaining time threshold, and a second buffer size field indicating the amount of data for the LCG calculated based on the first remaining time threshold.

11. A base station device (20) comprising: a transmitter (221) that transmits a Radio Resource Control (RRC) message; and a receiver (222) that receives a Delay Status Report (DSR) from a terminal device (10) that has been triggered based on information included in the RRC message indicating a first remaining time threshold used to trigger the DSR, wherein the triggered DSR is reserved in the terminal device, and the receiver receives from the terminal device either a first DSR MAC CE (Medium Access Control Element) or a second DSR MAC CE different from the first DSR MAC CE, the first DSR MAC CE being generated based on the presence of the reserved DSR and a second remaining time threshold for a Logical Channel Group (LCG) included in the RRC message.

12. The base station apparatus according to claim 11, wherein the receiving unit receives the first DSR MAC CE from the terminal device when the second remaining time threshold is set for at least one LCG and an Uplink Shared Channel (UL-SCH) resource can accommodate the first DSR MAC CE, and receives the second DSR MAC CE from the terminal device when the second remaining time threshold is not set and the UL-SCH resource can accommodate the second DSR MAC CE.

13. The base station device according to claim 11 or 12, wherein the receiving unit receives the SR from the terminal device when the reserved DSR exists in the terminal device, the UL-SCH resources are not available for new transmission, and there is no pending scheduling request (SR) already triggered by the DSR procedure for the same logical channel (LCH) as the DSR.

14. The base station device according to any one of claims 11 to 13, wherein the first DSR MAC CE includes an LCG field indicating the presence of delay information for the LCG, and when the LCG field indicates the presence of the delay information for the LCG, the first DSR MAC CE includes: a remaining time field indicating the shortest remaining time among the data of the LCG based on the second remaining time threshold; a buffer size field indicating the amount of data of the LCG calculated based on the second remaining time threshold; and a field indicating information regarding the pair of the remaining time field and the buffer size field.

15. The base station device of claim 14, wherein the LCG field in the first DSR MAC CE is a first LCG field, the remaining time field in the first DSR MAC CE is a first remaining time field, the buffer size field in the first DSR MAC CE is a first buffer size field, the second DSR MAC CE includes a second LCG field indicating the presence of delay information for the LCG, and when the second LCG field indicates the presence of the delay information for the LCG, the second DSR MAC CE includes: a second remaining time field indicating the shortest remaining time among the data of the LCG based on the first remaining time threshold, and a second buffer size field indicating the amount of data of the LCG calculated based on the first remaining time threshold.

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