Communication control method

Abstract

A communication control method according to one aspect is used in a wireless communication system. The communication control method comprises a step for a base station to perform linking a first Semi-Persistent Scheduling (SPS) setting and a second SPS setting with different cycles or linking between a first Configured Grant (CG) setting and a second CG setting with different cycles. Further, the communication control method comprises a step for the base station to transmit first linking information regarding either linking between the first SPS setting and the second SPS setting or linking between the first CG setting and the second CG setting to the user device.

Description

Communication Control Method

[0001] The present disclosure relates to a communication control method in a mobile communication system.

[0002] The Third Generation Partnership Project (3GPP) (registered trademark; the same applies hereinafter), a standardization project for mobile communication systems, has approved XR (eXtended Reality) for Release 18 of its specifications. XR is a broad term that includes virtual reality (VR), augmented reality (AR), and mixed reality (MR), and describes an environment that blends the real world with a virtual space. XR describes a blended environment of real space and virtual space generated by computer technology and wearable devices, and represents the interaction between humans and machines.

[0003] RP-213587, 3GPP TSG RAN Meeting #94e, “Study on XR Enhancements for NR”, Nokia, Dec. 6-17,20213GPP TR 38.838 V17.0.0 (2021-12)

[0004] A communication control method according to one aspect is a communication control method in a mobile communication system. The communication control method includes a step in which a base station either associates a first semi-persistent scheduling (SPS) setting with a second SPS setting, each having a different period, or associates a first configured grant (CG) setting with a second CG setting, each having a different period. The communication control method also includes a step in which the base station transmits, to a user equipment, first association information related to either the association between the first SPS setting and the second SPS setting or the association between the first CG setting and the second CG setting.

[0005] A communication control method according to one aspect is a communication control method in a mobile communication system, the communication control method including a step of a base station configuring an SPS setting or a CG setting for a user equipment, and a step of the base station transmitting, to the user equipment, a timing adjustment command for adjusting a start timing of a period indicated in the SPS setting or the CG setting.

[0006] FIG. 1 is a diagram illustrating an example of the configuration of a mobile communication system according to the first embodiment. FIG. 2 is a diagram illustrating an example of the configuration of a UE (user equipment) according to the first embodiment. FIG. 3 is a diagram illustrating an example of the configuration of a gNB (base station) according to the first embodiment. FIG. 4 is a diagram illustrating an example of the configuration of a protocol stack related to a user plane according to the first embodiment. FIG. 5 is a diagram illustrating an example of the configuration of a protocol stack related to a control plane according to the first embodiment. FIG. 6 is a diagram illustrating an example of an operation according to the first embodiment. FIGS. 7(A) and 7(B) are diagrams illustrating an example of the relationship between a traffic cycle and a CG cycle according to the first embodiment. FIG. 8 is a diagram illustrating an example of an operation according to the second embodiment.

[0007] An object of one aspect of the present disclosure is to provide a communication control method that enables appropriate communication using XR.

[0008] A mobile communication system according to an embodiment will be described with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

[0009] [First embodiment] (Configuration of mobile communication system) Fig. 1 is a diagram showing the configuration of a mobile communication system according to the first embodiment. The mobile communication system 1 conforms to the 5th Generation System (5GS) of the 3GPP standard. Although the following description will be given using 5GS as an example, the mobile communication system may also be at least partially based on an LTE (Long Term Evolution) system. Alternatively, the mobile communication system may also be at least partially based on a 6th Generation (6G) system.

[0010] The mobile communication system 1 includes a user equipment (UE) 100, a 5G radio access network (NG-RAN: Next Generation Radio Access Network) 10, and a 5G core network (5GC: 5G Core Network) 20. Hereinafter, the NG-RAN 10 may be simply referred to as the RAN 10. Furthermore, the 5GC 20 may be simply referred to as the core network (CN) 20.

[0011] The UE 100 is a mobile wireless communication device. The UE 100 may be any device that is used by a user. For example, the UE 100 may be a mobile phone terminal (including a smartphone), a tablet terminal, a notebook PC, a communication module (including a communication card or a chipset), a sensor or a device provided in a sensor, a vehicle or a device provided in a vehicle (Vehicle UE), or an aircraft or a device provided in an aircraft (Aerial UE).

[0012] The UE 100 includes an XR device. The XR device is, for example, a device capable of XR processing. Specific examples of XR devices include a head-mounted display (HMD) that can be worn on a human head, eyeglass-type AR glasses (or smart glasses), a handheld mobile handset, a wristwatch-type device (smart watch), and a smartphone. These XR devices may also be referred to as wearable devices. The HMD includes a display, lenses, a tracking sensor, a camera, a control unit (e.g., a central processing unit (CPU) or a graphics processing unit (GPU)) that performs XR-related processing, and a communication function. The AR glasses have a function for transmitting images. The mobile handset may include various sensors such as a tracking sensor. The HMD, AR glasses, wristwatch-type device, and mobile handset have a communication function that supports a 5G system, etc. In the following, the UE 100 will be described as including such an XR device.

[0013] The NG-RAN 10 includes a base station (called a "gNB" in a 5G system) 200. The gNBs 200 are connected to each other via an Xn interface, which is an interface between base stations. The gNB 200 manages one or more cells. The gNB 200 performs wireless communication with a UE 100 that has established a connection with its own cell. The gNB 200 has a radio resource management (RRM) function, a routing function for user data (hereinafter simply referred to as "data"), a measurement control function for mobility control and scheduling, and the like. The term "cell" is used to indicate the smallest unit of a wireless communication area. The term "cell" is also used to indicate a function or resource for wireless communication with the UE 100. One cell belongs to one carrier frequency (hereinafter simply referred to as "frequency").

[0014] In addition, gNBs can also be connected to the Evolved Packet Core (EPC), which is the core network of LTE. LTE base stations can also be connected to 5GC. LTE base stations and gNBs can also be connected via an inter-base station interface.

[0015] The 5GC20 includes an Access and Mobility Management Function (AMF) and a User Plane Function (UPF) 300. The AMF performs various mobility controls for the UE 100. The AMF manages the mobility of the UE 100 by communicating with the UE 100 using NAS (Non-Access Stratum) signaling. The UPF controls data forwarding. The AMF and the UPF are connected to the gNB 200 via an NG interface, which is an interface between a base station and a core network.

[0016] 2 is a diagram showing the configuration of the UE 100 (user equipment) according to the first embodiment. The UE 100 includes a receiving unit 110, a transmitting unit 120, and a control unit 130. The receiving unit 110 and the transmitting unit 120 constitute a wireless communication unit that performs wireless communication with the gNB 200.

[0017] The receiving unit 110 performs various types of reception under the control of the control unit 130. The receiving unit 110 includes an antenna and a receiver. The receiver converts a radio signal received by the antenna into a baseband signal (received signal) and outputs the baseband signal to the control unit 130.

[0018] The transmitting unit 120 performs various transmissions under the control of the control unit 130. The transmitting unit 120 includes an antenna and a transmitter. The transmitter converts a baseband signal (transmission signal) output by the control unit 130 into a radio signal and transmits it from the antenna.

[0019] The control unit 130 performs various controls and processes in the UE 100. Such processes include processes of each layer described below. The control unit 130 includes at least one processor and at least one memory. The memory stores programs executed by the processor and information used in the processes by the processor. The processor may include a baseband processor and a CPU (Central Processing Unit). The baseband processor performs modulation / demodulation, encoding / decoding, etc. of baseband signals. The CPU executes programs stored in the memory to perform various processes. Note that the control unit 130 may perform each process or operation in the UE 100 in each of the embodiments described below.

[0020] 3 is a diagram showing the configuration of a gNB 200 (base station) according to the first embodiment. The gNB 200 includes a transmitter 210, a receiver 220, a controller 230, and a backhaul communication unit 240. The transmitter 210 and the receiver 220 constitute a wireless communication unit that performs wireless communication with the UE 100. The backhaul communication unit 240 constitutes a network communication unit that communicates with the CN 20.

[0021] The transmitting unit 210 performs various transmissions under the control of the control unit 230. The transmitting unit 210 includes an antenna and a transmitter. The transmitter converts a baseband signal (transmission signal) output by the control unit 230 into a radio signal and transmits it from the antenna.

[0022] The receiving unit 220 performs various types of reception under the control of the control unit 230. The receiving unit 220 includes an antenna and a receiver. The receiver converts a radio signal received by the antenna into a baseband signal (received signal) and outputs the baseband signal to the control unit 230.

[0023] The control unit 230 performs various controls and processes in the gNB 200. Such processes include processes for each layer described below. The control unit 230 includes at least one processor and at least one memory. The memory stores programs executed by the processor and information used in the processes by the processor. The processor may include a baseband processor and a CPU. The baseband processor performs modulation / demodulation, encoding / decoding, etc. of baseband signals. The CPU executes programs stored in the memory to perform various processes. Note that the control unit 230 may perform each process or operation in the gNB 200 in each of the embodiments described below.

[0024] The backhaul communication unit 240 is connected to adjacent base stations via an Xn interface, which is an interface between base stations. The backhaul communication unit 240 is connected to the AMF / UPF 300 via an NG interface, which is an interface between a base station and a core network. Note that the gNB 200 is composed of a CU (Central Unit) and a DU (Distributed Unit) (i.e., functionally divided), and the two units may be connected by an F1 interface, which is a fronthaul interface.

[0025] FIG. 4 is a diagram showing the configuration of a protocol stack of a radio interface of a user plane that handles data.

[0026] The user plane radio interface protocol includes a physical (PHY) layer, a medium 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.

[0027] The PHY layer performs encoding / decoding, modulation / demodulation, antenna mapping / demapping, and resource mapping / demapping. Data and control information are transmitted between the PHY layer of UE100 and the PHY layer of gNB200 via a physical channel. The PHY layer of UE100 receives downlink control information (DCI) transmitted from gNB200 on a physical downlink control channel (PDCCH). Specifically, UE100 performs blind decoding of the PDCCH using a radio network temporary identifier (RNTI) and acquires the successfully decoded DCI as DCI addressed to the UE. The DCI transmitted from gNB200 has a CRC parity bit scrambled by the RNTI added.

[0028] The MAC layer performs data priority control, retransmission processing using Hybrid Automatic Repeat reQuest (HARQ), random access procedures, etc. Data and control information are transmitted between the MAC layer of the UE 100 and the MAC layer of the gNB 200 via a transport channel. The MAC layer of the gNB 200 includes a scheduler. The scheduler determines the uplink and downlink transport format (transport block size, modulation and coding scheme (MCS)) and the resource blocks to be allocated to the UE 100.

[0029] The RLC layer transmits data to the receiving RLC layer using the functions of the MAC layer and PHY layer. Data and control information are transmitted between the RLC layer of the UE 100 and the RLC layer of the gNB 200 via a logical channel.

[0030] The PDCP layer performs header compression / decompression, encryption / decryption, and the like.

[0031] The SDAP layer maps IP flows, which are units for Quality of Service (QoS) control by the core network, to radio bearers, which are units for QoS control by the Access Stratum (AS). Note that if the RAN is connected to the EPC, SDAP may not be required.

[0032] FIG. 5 is a diagram showing the configuration of a protocol stack of a radio interface of a control plane that handles signaling (control signals).

[0033] The protocol stack of the radio interface of the control plane has a Radio Resource Control (RRC) layer and a Non-Access Stratum (NAS) instead of the SDAP layer shown in FIG.

[0034] RRC signaling for various settings is transmitted between the RRC layer of UE100 and the RRC layer of gNB200. The RRC layer controls logical channels, transport channels, and physical channels according to the establishment, re-establishment, and release of radio bearers. When there is a connection (RRC connection) between the RRC of UE100 and the RRC of gNB200, UE100 is in an RRC connected state. When there is no connection (RRC connection) between the RRC of UE100 and the RRC of gNB200, UE100 is in an RRC idle state. When the connection between the RRC of UE100 and the RRC of gNB200 is suspended, UE100 is in an RRC inactive state.

[0035] The NAS, which is located above the RRC layer, performs session management, mobility management, etc. NAS signaling is transmitted between the NAS of the UE 100 and the NAS of the AMF 300. Note that the UE 100 has an application layer and the like in addition to the radio interface protocol. Also, the layer below the NAS is called an Access Stratum (AS).

[0036] (About XR) As described above, XR is a broad term that includes, for example, virtual reality (VR), augmented reality (AR), and mixed reality (MR), and describes an environment that combines the real world and a virtual space. XR is also, for example, a general term for such various types of realities. XR is also, for example, a general term for technology that combines the real world and a virtual space to enable perception of things that do not exist in reality.

[0037] In XR, human-to-machine and human-to-human communication is performed with the aid of a portable or wearable end-user device, the UE 100. Such communication enables XR to be applied in various application areas such as entertainment, healthcare, or education.

[0038] Along with XR, cloud gaming (CG) is one of the use cases in future mobile systems. Cloud gaming is a general term for use cases in which, for example, most of the calculations related to a game are offloaded to an edge server or a remote server. In cloud gaming, the UE 100 transmits information related to pose and / or control. The cloud performs calculations related to video data and the like based on this information and provides the UE 100 with video and other game-related data.

[0039] Virtual reality (VR) refers to the creation of an environment that is not the original (or real world) but is essentially functionally the same as the original by stimulating the user's senses. In virtual reality (VR), the user typically wears an HMD, the user's field of vision is replaced with simulated visual elements, and accompanying audio is provided to the user through headphones. Virtual spaces are designed to mimic sensory stimuli such as sight and hearing in the real world as naturally as possible. Virtual reality (VR) can also include the metaverse, a virtual space (or service) built on a computer or computer network that is different from the real world.

[0040] Augmented reality (AR) is a technology that displays a virtual space overlaid on the real world. Augmented reality (AR) also provides additional information (artificially generated items or content) overlaid on the user's real environment. The additional information can be perceived directly without sensors or indirectly via sensors.

[0041] Furthermore, mixed reality (MR) is a technology that combines and / or blends the real world and a virtual space to create a space in which they interact with each other in real time. Mixed reality (MR) is an advanced form of augmented reality (AR) and is constructed with the intention of inserting virtual elements into a physical scene to give the illusion that they are part of the actual scene.

[0042] Typical forms of XR include virtual reality (VR), augmented reality (AR), and mixed reality (MR), but areas that interpolate between these may also be included in XR.

[0043] Many XR and cloud gaming (CG) use cases are characterized by video stream traffic in the DL direction and a combination of pose and / or control traffic and video stream traffic in the UL direction. The video stream has a higher data rate than other use cases, and data related to pose and / or control is updated frequently. Furthermore, XR and cloud gaming (CG) are characterized by the fact that DL traffic and UL traffic are more sensitive to delays than other use cases.

[0044] (XR Traffic Model) The following describes the XR traffic model. XR traffic models include (1) a general traffic model and (2) a specific traffic model. First, (1) the general traffic model will be described. The (1) general traffic model includes (1.1) a traffic model in the DL direction and (1.2) a traffic model in the UL direction.

[0045] (1) General traffic model

[0046] (1.1) Traffic Model in DL Direction There are two types of traffic models in the DL direction: a single-stream DL traffic model and a multi-stream DL traffic model. The two traffic models can be summarized as follows:

[0047] (1.1.1) Single-Stream DL Traffic Model: A Sequence of Video Frames

[0048] (1.1.2) Multi-Stream DL Traffic Model:

[0049] (1.1.2.1) Option #1: Two streams, the first stream being an I (Intra-coded) stream and the second stream being a P (Predicted) stream. Option #1 includes a slice-based traffic model (Option #1A) and a GOP (Group-Of-Picture)-based traffic model (Option #1B).

[0050] (1.1.2.1A) Option #1A (Slice-based): The first stream is an I slice (I stream), and the second stream is a P slice (P stream). Here, an I slice is, for example, a slice in which all macroblocks included in the I slice are coded by intra-frame prediction. A P slice is, for example, a slice in which all macroblocks included in the P slice are coded by intra-frame prediction or inter-frame prediction. When a video frame is sliced ​​into N slices, one slice can be an I slice, and the remaining (N-1) slices can be P slices.

[0051] (1.1.2.1B) Option #1B (GOP-based): The first stream is an I-frame (I-stream), and the second stream is a P-slice (P-stream). Here, an I-frame is a frame encoded using a video frame without using other video frames. A P-frame is a frame encoded using a video frame preceding it in time. If the GOP size is K frames, an I-frame is transmitted every K frames. A GOP includes one I-frame and (K-1) P-frames.

[0052] (1.1.2.2) Option #2: A traffic model with two streams, where the first stream is video and the second stream is audio and / or data.

[0053] (1.1.2.3) Option #3: A traffic model in which the first stream is a field of view (FOV) and the second stream is an omnidirectional view. For example, the FOV is video data from the user's line of sight, and the omnidirectional view is omnidirectional video data centered on the user, including video data from the user's line of sight.

[0054] (1.2) Traffic Model in UL Direction The traffic model in the UL direction includes an attitude and / or control stream traffic model, in which the UE 100 transmits data related to attitude and / or control.

[0055] (2) Specific Traffic Models Specific traffic models include (2.1) virtual reality (VR), (2.2) augmented reality (AR), and (2.3) cloud gaming (CG) traffic models.

[0056] (2.1) Traffic Model of Virtual Reality (VR) The traffic model of virtual reality (VR) can be summarized as follows:

[0057] (2.1.1) DL Stream: Single-stream model: Same as above (1.1.1) "Single-stream DL traffic model" (series of video frames) Multi-stream model: Same as above (1.1.2.2) "Option #2" (first stream is video, second stream is audio and / or data)

[0058] (2.1.2) UL stream: Same as (1.2) "Traffic model in UL direction" above

[0059] (2.2) Traffic Model of Augmented Reality (AR) The traffic model of augmented reality (AR) can be summarized as follows.

[0060] (2.2.1) DL stream: same as (2.1.1) above

[0061] (2.2.2) UL Stream: Model #1: 1-stream model Model #2: 2-stream model: the first stream is attitude and / or control, the second stream is a combination of scene (e.g. continuous video), video, data, and audio Model #3A: 3-stream Model A: the first stream is attitude and / or control, the second stream is a combination of scene stream and video stream, the third stream is a combination of audio and data Model #3B: 3-stream Model B: the first stream is attitude and / or control, the second stream is video I stream, the third stream is video P stream

[0062] (2.3) Cloud Gaming (CG) Traffic Model The traffic model for cloud gaming (CG) can be summarized as follows:

[0063] (2.3.1) DL Stream Single-stream model: Same as above (1.1.1) "Single-stream DL traffic model" (series of video frames) Multi-stream model: Same as above (1.1.2) "Multi-stream DL traffic model"

[0064] (2.3.2) UL stream: Same as (1.2) "Traffic model in UL direction" above

[0065] (SPS and CG) In a 5G system, a scheduling method called SPS (Semi-Persistent Scheduling) may be used in the DL direction. SPS is a scheduling method in which, for example, when radio resources in the DL direction are allocated by DCI (Downlink Control Information) transmitted using a PDCCH (Physical Downlink Control Channel), the UE 100 can then periodically use the radio resources to communicate in the DL direction without using the DCI. Unlike dynamic scheduling, which performs scheduling using DCI for each PDSCH (Physical Downlink Shared Channel), SPS enables semi-fixed scheduling, which makes it possible to reduce the number of processing steps in the UE 100. The period is notified from the gNB 200 to the UE 100 by the SPS setting (SPS-Config) included in an RRC message (for example, an RRC setup message or an RRC reconfiguration message). The gNB 200 can also set multiple SPS settings with different periods.

[0066] In addition, in 5G systems, a scheduling method called CG (Configured Grant) may be used in the UL direction. CG is a scheduling method in which, for example, once radio resources in the UL direction are allocated by DCI transmitted using the PDCCH, the UE 100 can then periodically use the radio resources to communicate in the UL direction without using DCI. The period is notified from the gNB 200 to the UE 100 by a CG setting (ConfiguredGrantConfig) included in an RRC message (for example, an RRC Setup message or an RRC Reconfiguration message). Note that there are two types of CG: Type 1, which allows UL transmission without using DCI, and Type 2, which performs UL transmission using DCI. In the case of Type 1, the radio resources are directly included in the CG setting. gNB200 is also capable of setting multiple CG settings with different periods.

[0067] (Communication Control Method According to First Embodiment) In the above-described XR traffic model, for example, the UL stream is shown as a single stream model that transmits traffic related to pose and / or control (above (1.2)). However, in reality, in addition to traffic related to pose and / or control, a single stream may be transmitted that includes different traffic, such as video data. In addition, in the case of multiple streams, different traffic occurs for each stream, as shown in the above-described XR traffic model.

[0068] Since such XR traffic may be periodic, it is considered that the CG setting and the SPS setting that enable periodic transmission or reception are effective. Here, it is assumed that UL transmission is performed using the CG setting for the XR traffic.

[0069] In this case, if radio resources are allocated based on the CG setting assuming that traffic related to attitude and / or control is included in the stream, the radio resources may be insufficient. On the other hand, if radio resources are allocated based on the CG setting assuming that traffic related to video data is included in the stream, the radio resources may be insufficient. If radio resources are insufficient, multiple CG settings can be used, but under current specifications, the CG settings are independent and it is not possible to set the relationship between multiple CG settings. Furthermore, although the CG setting allows UL transmission using radio resources periodically, video data traffic in XR traffic may occur aperiodically. Therefore, for example, the UE 100 may not be able to properly transmit XR traffic using the CG setting.

[0070] Similarly, when DL transmission is performed using the SPS setting, there may be a surplus or shortage of radio resources. In addition, there may be a case where the UE 100 cannot properly receive video data traffic that occurs aperiodically.

[0071] As described above, since various traffic models exist for the XR traffic, for example, there is a case where communication of the XR traffic cannot be performed appropriately in the UE 100. Therefore, in the mobile communication system 1, there is a case where communication by XR cannot be performed appropriately.

[0072] The first embodiment aims to appropriately perform communication by XR in a mobile communication system 1.

[0073] Therefore, in the first embodiment, a plurality of SPS settings or a plurality of CG settings are made, and the plurality of SPS settings or the plurality of CG settings are linked together.

[0074] Specifically, first, the base station (e.g., gNB200) either links the first SPS setting and the second SPS setting having different periods, or links the first CG setting and the second CG setting having different periods. Second, the base station transmits first linking information regarding either the linking of the first SPS setting and the second SPS setting or the linking of the first CG setting and the second CG setting to the user apparatus (e.g., UE100).

[0075] As a result, for example, the UE 100 is able to recognize that the first CG setting and the second CG setting are linked, and can use the two settings with different periods to transmit video data traffic at a higher data rate than other traffic or transmit non-periodic video data traffic. Furthermore, for example, the UE 100 is able to recognize that the first SPS setting and the second SPS setting are linked, and can use the two settings with different periods to receive video data traffic at a higher data rate than other traffic or receive non-periodic video data traffic. Therefore, it is possible to appropriately perform communication using XR in the mobile communication system 1.

[0076] (Operation Example of First Embodiment) Fig. 6 is a diagram illustrating an operation example of the first embodiment. Note that Fig. 6 illustrates an example of SPS settings. First, an example of linking multiple SPS settings will be described.

[0077] As shown in FIG. 6, in step S10, the gNB 200 configures the UE 100 with multiple SPS configurations, each with a different period. For example, the gNB 200 configures the UE 100 with a first SPS configuration with a first period and a second SPS configuration with a second period that is different from the first period. As described above, the SPS configuration includes a periodicity. Note that each SPS configuration includes a different index value (sps-ConfigIndex). For example, the first SPS configuration includes index #1, and the second SPS configuration includes index #2.

[0078] In step S11, the gNB 200 links the multiple SPS settings with different periods set in step S10 and sets linking information related to the linking of the multiple SPS settings. For example, the gNB 200 links the first SPS setting and the second SPS setting and sets linking information related to the linking of the first SPS setting and the second SPS setting. The linking may be performed, for example, by linking index #1 of the first SPS setting and index #2 of the second SPS setting using an index value, and setting the linking information. The linked multiple SPS settings are recognized as a single SPS in the UE 100. For example, if index #1 of the first SPS setting and index #2 of the second SPS setting are linked, the two SPS settings are recognized as a single SPS. On the other hand, for example, if index #3 and index #4 are not linked, the third SPS setting of index #3 and the fourth SPS setting of index #4 are recognized as separate and independent SPS settings.

[0079] In addition, the gNB200 may further configure multiple CS-RNTIs for the UE100. In this case, the gNB200 may link each SPS configuration to each CS-RNTI and configure linking information between each SPS configuration and each CS-RNTI. For example, the gNB200 links the first SPS configuration (index #1) to the first CS-RNTI and links the second SPS configuration (index #2) to the second CS-RNTI. Then, for example, the gNB200 configures the UE100 with linking information (e.g., second linking information) regarding the linking between the first SPS configuration and the first CS-RNTI and linking information (e.g., third linking information) regarding the linking between the second SPS configuration and the second CS-RNTI.

[0080] In step S12, the gNB 200 transmits configuration information to the UE 100. The gNB 200 may transmit an RRC message or a MAC CE, etc., including the configuration information, to the UE 100. The configuration information includes multiple SPS configurations configured in step S10 and the linking information configured in step S11. The configuration information may be transmitted in separate (or different types of) messages, with the SPS configuration in step S10 and the linking information configured in step S11 being different configuration information. Furthermore, the configuration information may include linking information between each SPS configuration and each CS-RNTI. The linking information may be transmitted in separate (or different types of) messages, as configuration information different from the configuration information transmitted in step S12.

[0081] In step S13, upon receiving the setting information, the UE 100 monitors the PDCCH in accordance with the period of each SPS setting.

[0082] In step S14, the UE 100 determines that the radio resource allocation by the PDCCH received at each SPS period is valid. For example, assume that the first SPS setting of index #1 and the second SPS setting of index #2 are linked. In this case, the UE 100 performs, for example, the following processing.

[0083] That is, when the UE 100 successfully descrambles the first DCI included in the first PDCCH using the CS-RNTI included in the configuration information for the first PDCCH monitored at the reception timing of the first period indicated in the first SPS setting, the UE 100 recognizes that radio resource allocation by the first DCI has occurred. Furthermore, when the UE 100 successfully descrambles the second DCI included in the second PDCCH monitored at the reception timing of the second period indicated in the second SPS setting using the CS-RNTI included in the configuration information, the UE 100 recognizes that radio resource allocation by the second DCI has occurred. Then, when the UE 100 recognizes that these two radio resource allocations have occurred, the UE 100 determines that the two radio resource allocations are valid. Here, the first SPS setting and the second SPS setting are linked. Therefore, when the UE 100 recognizes that radio resource allocation by the first DCI has occurred, it may recognize that radio resource allocation has occurred in the first period and the second period. Furthermore, when the UE 100 recognizes that radio resource allocation has occurred by the second DCI, the UE 100 may recognize that radio resource allocation has occurred in the first period and the second period.

[0084] In addition, in the case of a third SPS setting with unlinked index #3, if UE100 successfully descrambles the third DCI included in the third PDCCH using the CS-RNTI included in the setting information for the third PDCCH monitored at the reception timing of the third period indicated in the third SPS setting, UE100 determines that the radio resource allocation using the third DCI is valid.

[0085] When the UE 100 further receives linking information linking each SPS setting with each CS-RNTI, it determines that the resource allocation by each PDCCH descrambled by each CS-RNTI is valid. For example, it is assumed that the first SPS setting and the second SPS setting are linked, the first SPS setting and the first CS-RNTI are linked, and the second SPS setting and the second CS-RNTI are linked. In this case, the UE 100 performs, for example, the following processing. That is, the UE 100 monitors at the reception timing of the first period indicated in the first SPS setting, and if descrambling of the third DCI included in the third PDCCH using the first CS-RNTI is successful, it recognizes the radio resource allocation by the third DCI. Furthermore, the UE 100 monitors at the reception timing of the second period indicated in the second SPS setting, and if descrambling of the fourth DCI included in the fourth PDCCH using the second CS-RNTI is successful, the UE 100 recognizes the radio resource allocation by the fourth DCI. Then, when the UE 100 recognizes these two radio resource allocations, it determines that the two radio resource allocations are valid. Also, it is assumed that the first SPS setting and the second SPS setting are linked, and the first SPS setting and the second SPS setting are linked to the fifth CS-RNTI. That is, it is assumed that one CS-RNTI is linked to the two SPS settings. In this case, the UE 100 may monitor at the reception timing of the first period indicated in the first SPS setting and the second period indicated in the second SPS setting, and if descrambling of the fifth DCI included in the fifth PDCCH using the fifth CS-RNTI is successful, it may recognize the radio resource allocation by the fifth DCI.

[0086] In step S15, UE 100 receives the PDSCH in accordance with the period of each SPS setting. For example, UE 100 receives the first PDSCH by using the radio resource according to the first DCI for each first period, and receives the second PDSCH by using the radio resource according to the second DCI for each second period. Also, for example, UE 100 receives the third PDSCH by using the radio resource according to the third DCI for each first period, and receives the fourth PDSCH by using the radio resource according to the fourth DCI for each second period. Also, UE 100 may receive the fifth PDSCH by using the radio resource according to the fifth DCI for each first period and each second period.

[0087] (Modification of First Embodiment) In the first embodiment, an example of SPS setting has been described. For example, the present invention may be applied to CG setting.

[0088] That is, the gNB 200 configures the UE 100 with multiple CG settings, each with a different period (step S10). Next, the gNB 200 links the multiple CG settings and configures the UE 100 with linking information related to the linking (steps S11 and S12). For example, the gNB 200 links the first CG setting (index #1) and the second CG setting (index #2), each with a different period, and transmits to the UE 100 linking information (e.g., first linking information) related to the linking of the first CG setting and the second CG setting.

[0089] In addition, gNB200 may further link each CG setting to each CS-RNTI. For example, gNB200 links the first CG setting to the first CS-RNTI, and links the second CG setting to the second CS-RNTI. Then, gNB200 transmits to UE100 linking information (e.g., second linking information) regarding the linking between the first CG setting and the first CS-RNTI, and linking information (e.g., third linking information) regarding the linking between the second CG setting and the second CS-RNTI.

[0090] The UE 100 monitors the PDCCH in accordance with the period of each CG setting (step S13) and determines that the radio resource allocation by each PDCCH is valid (step S14). For example, it is assumed that the first CG setting and the second CG setting are linked. In this case, the UE 100 performs, for example, the following process. That is, when the UE 100 successfully descrambles the first DCI included in the first PDCCH using the CS-RNTI for the first PDCCH monitored at the reception timing of the first period indicated in the first CG setting, the UE 100 recognizes that the radio resource allocation by the first DCI has occurred. Furthermore, when the UE 100 successfully descrambles the second DCI included in the second PDCCH using the CS-RNTI for the second PDCCH monitored at the reception timing of the second period indicated in the second CG setting, the UE 100 recognizes that the radio resource allocation by the second DCI has occurred. Then, when the UE 100 recognizes the occurrence of these two radio resource allocations, the UE 100 determines that the two radio resource allocations are valid.

[0091] Then, the UE 100 transmits a PUSCH (Physical Uplink Shared Channel) in accordance with the period of each CG setting (step S15). For example, the UE 100 transmits the first PUSCH by using the radio resource according to the first DCI for each first period indicated in the first CG setting, and transmits the second PUSCH by using the radio resource according to the second DCI for each second period indicated in the second CG setting.

[0092] Furthermore, when each CG setting and each CS-RNTI are linked, for example, the following is assumed. That is, it is assumed that the first CG setting and the second CG setting are linked, the first CG setting and the first CS-RNTI are linked, and the second CG setting and the second CS-RNTI are linked. In this case, the UE 100 performs, for example, the following processing. That is, the UE 100 monitors the third PDCCH at the reception timing of the first period indicated in the first CG setting, and if descrambling of the third DCI included in the third PDCCH using the first CS-RNTI is successful, the UE 100 recognizes the radio resource allocation by the third DCI. Furthermore, the UE 100 monitors at the reception timing of the second period indicated in the second CG setting, and if descrambling of the fourth DCI included in the fourth PDCCH using the second CS-RNTI is successful, the UE 100 recognizes the radio resource allocation by the fourth DCI. Then, when the UE 100 recognizes these two radio resource allocations, it determines that the two radio resource allocations are valid. Then, the UE 100 transmits the third PUSCH using the radio resources according to the third DCI for each first period indicated by the first CG setting, and transmits the fourth PUSCH using the radio resources according to the fourth DCI for each second period indicated by the second CG setting. Also, it is assumed that the first CG setting and the second CG setting are linked, and that the first CG setting and the second CG setting are linked to the fifth CS-RNTI. That is, it is assumed that one CS-RNTI is linked to the two CG settings. In this case, the UE 100 may monitor at the reception timing of the first period indicated by the first CG setting and the second period indicated by the second CG setting, and recognize the radio resource allocation according to the fifth DCI if descrambling of the fifth DCI included in the fifth PDCCH using the fifth CS-RNTI is successful. Then, the UE 100 may transmit the fifth PUSCH by using the radio resources of the fifth DCI for each first period and each second period.

[0093] Second Embodiment Next, a second embodiment will be described.

[0094] The following case is assumed for the CG setting: That is, as shown in Fig. 7(A), for example, there is no particular problem when the period of traffic received from the application layer in the AS of UE 100 matches the period indicated in the CG setting, and the timing of receiving traffic from the application layer matches the transmission timing permitted by the CG setting.

[0095] However, as shown in FIG. 7B , assume that the period of traffic received from the application layer matches the period indicated by the CG setting, but the timing of receiving traffic from the application layer differs from the transmission timing permitted by the CG setting. In this case, the UE 100 transmits packets according to the CG setting at a timing delayed from the timing of receiving traffic from the application layer. Therefore, the transmission timing of traffic transmitted from the UE 100 is delayed, and this delay may result in a transmission delay. This transmission delay may not necessarily be desirable in terms of the user experience (UX) of a user using the UE 100 (or an XR device).

[0096] 7(A) and 7(B) show examples of CG configuration, but the same applies to SPS configuration. That is, if the timing at which UE100 receives traffic from gNB200 does not match the timing at which the AS of gNB200 outputs the received traffic to the application layer, a transmission delay (or processing delay) may occur. Alternatively, if the traffic received by gNB200 from 5GC20 (e.g., UPF300) does not match the SPS transmission timing, a transmission delay (or processing delay) may occur. Such a transmission delay may not necessarily be a desirable user experience.

[0097] Therefore, in either the CG setting or the SPS setting, communication via XR may not always be performed properly.

[0098] Therefore, in the second embodiment, first, a base station (e.g., gNB 200) configures an SPS setting or a CG setting for a user apparatus (e.g., UE 100). Second, the base station transmits a timing adjustment command to the user apparatus to adjust the start timing of the period indicated in the SPS setting or CG setting.

[0099] As a result, for example, in the AS of the UE 100, it is possible to adjust the start timing of the period indicated in the CG setting so as to coincide with the timing of receiving traffic from the application layer. Also, for example, in the AS of the UE 100, it is possible to adjust the start timing of the period indicated in the SPS setting so as to coincide with the timing of outputting traffic to the application layer. Therefore, transmission delay is suppressed, and it is possible to appropriately perform communication by XR in the mobile communication system 1.

[0100] (Example of Operation of Second Embodiment) Fig. 8 is a diagram showing an example of operation of the second embodiment. However, Fig. 8 shows an example of CG setting. First, the example of CG setting will be described.

[0101] As shown in Figure 8, in step S20, gNB200 configures CG settings for UE100.

[0102] In step S21, the gNB 200 transmits configuration information including the CG configuration to the UE 100. The gNB 200 may transmit the configuration information using an RRC message, a MAC CE, or the like.

[0103] In step S22, the AS of UE00 recognizes that there is a discrepancy between the timing at which it receives packets from the application layer (or NAS layer) and the timing at which it transmits packets permitted by the CG setting.

[0104] In addition, when the UE 100 recognizes that there is the discrepancy, it may request the gNB 200 to adjust the timing (step S23). The UE 100 may make the request by transmitting a MAC CE or DCI including the request to the gNB 200. The request may include difference information indicating the difference between the timing at which the AS of the UE 100 receives a packet from the application layer (or NAS layer) and the transmission timing of the packet permitted by the CG setting. The difference information may include, in addition to information indicating the timing difference, the direction on the time axis in which the difference occurs (for example, information indicating whether the transmission timing of the packet permitted by the CG setting is to be earlier or later than the current setting value).

[0105] In step S24, the gNB 200 transmits a timing adjustment command to the UE 100. The timing adjustment command is, for example, a command to adjust the start timing of the period indicated in the CG setting. The timing adjustment command includes, for example, the following information:

[0106] That is, the timing adjustment command includes information specifying the start timing for monitoring the PDCCH next. The cycle indicated in the CG configuration is also the cycle for monitoring the PDCCH. Therefore, the timing adjustment command includes, for example, information about the timing for starting monitoring the PDCCH. The start timing information may be information specifying n slots after the current slot. Alternatively, the start timing information may be information representing the difference (±n slots) from the start timing (or the next start timing) of the cycle indicated in the CG configuration to the start timing after timing adjustment. The start timing may be expressed in units of subframes, msec, etc., other than slots.

[0107] In addition, when the gNB 200 receives a timing adjustment request (step S23) from the UE 100, the gNB 200 may transmit a timing adjustment command in response to receiving the request. In this case, the timing adjustment command may include a start timing corresponding to difference information indicating the difference between the timing at which the AS of the UE 100 receives a packet from the application layer (or NAS layer) and the transmission timing of the packet permitted by the CG setting.

[0108] In addition, gNB200 may transmit a timing adjustment command to UE100 by transmitting a MAC CE or DCI including the timing adjustment command to UE100.

[0109] In step S25, in response to receiving the timing adjustment command, UE100 continues transmitting the PUSH at the period indicated in the CG setting (step S20), starting from the start timing specified in the timing adjustment command.

[0110] (Modification of Second Embodiment) In the first embodiment, the timing adjustment command for CG settings has been described, but the present invention is not limited to this.

[0111] For example, a timing adjustment command for SPS configuration may be transmitted from the gNB 200 to the UE 100 (step S24). In this case, the gNB 200 transmits a timing adjustment command to the UE 100 to adjust the start timing of the period indicated in the SPS configuration (step S20) (step S24). The information contained in the timing adjustment command may be the same as that in the first embodiment. The gNB 200 monitors the PDCCH at the timing specified in the timing adjustment command, receives the PDSCH using the radio resources included in the PDCCH, and thereafter continues to receive the PDSCH at the period indicated in the SPS configuration (step S25).

[0112] Further, for example, a timing adjustment command for the DRX setting may be transmitted from the gNB 200 to the UE 100 (step S24). In this case, the timing adjustment command includes, for example, information specifying the start timing of the on duration (On Duration) in the DRX setting (step S20) (i.e., the start timing of the onDurationTimer). The UE 100 starts receiving the PDSCH at the specified timing (step S25).

[0113] [Other embodiments] A program may be provided that causes a computer to execute each process performed by the UE 100 or the gNB 200. The program may be recorded on a computer-readable medium. Using a computer-readable medium, it is possible to install the program on a computer. Here, the computer-readable medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, and may be, for example, a recording medium such as a CD-ROM and / or a DVD-ROM.

[0114] In addition, circuits that perform each process performed by UE100 or gNB200 may be integrated, and at least a portion of UE100 or gNB200 may be configured as a semiconductor integrated circuit (chip set, SoC: System on a chip).

[0115] Although one embodiment has been described in detail above with reference to the drawings, the specific configuration is not limited to the above, and various design changes can be made within the scope of the gist. Furthermore, it is also possible to combine all or part of each embodiment, each operation, each process, and each step within the scope of consistent combinations.

[0116] As used in this disclosure, the terms "based on" and "depending on" do not mean "based only on" or "depending only on," unless expressly stated otherwise. The term "based on" means both "based only on" and "based at least in part on." Similarly, the term "depending on" means both "based only on" and "at least in part on." Furthermore, "obtain" may mean obtaining information from stored information, obtaining information from information received from another node, or obtaining information by generating the information. The terms "include," "comprise," and variations thereof do not mean including only the listed items, but may also mean including only the listed items or including additional items in addition to the listed items. Furthermore, as used in this disclosure, the term "or" is not intended to mean an exclusive or. Furthermore, any reference to an element using a designation such as "first," "second," etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used herein as a convenient method of distinguishing between two or more elements. Thus, reference to a first and a second element does not imply that only two elements may be employed therein, or that the first element must precede the second element in some way. In this disclosure, when articles are added by translation, such as a, an, and the in English, these articles are intended to include the plural unless the context clearly dictates otherwise.

[0117] This application claims priority from Japanese Patent Application No. 2022-073809 (filed April 27, 2022), the entire contents of which are incorporated herein by reference.

[0118] (Supplementary Note) In one embodiment, (Supplementary Note 1) a communication control method in a mobile communication system includes a step in which a base station performs one of linking a first SPS (Semi-Persistent Scheduling) setting and a second SPS setting, each having a different period, and linking a first CG (Configured Grant) setting and a second CG setting, each having a different period, and a step in which the base station transmits, to a user device, first linking information regarding either the linking between the first SPS setting and the second SPS setting or the linking between the first CG setting and the second CG setting.

[0119] (Supplementary Note 2) The communication control method of (Supplementary Note 1) above may further include a step in which the user equipment receives a first PDSCH (Physical Downlink Shared Channel) or transmits a first PUSCH (Physical Uplink Shared Channel) by using a first radio resource included in a first PDCCH (Physical Downlink Control Channel) received at a reception timing of a first period indicated in the first SPS setting or the first CG setting for each of the first period, and receives a second PDSCH or transmits a second PUSCH by using a second radio resource included in a second PDCCH received at a reception timing of a second period indicated in the second SPS setting or the second CG setting for each of the second period.

[0120] (Supplementary Note 3) In the communication control method of (Supplementary Note 1) or (Supplementary Note 2) above, the linking step includes a step in which the base station links the first SPS setting with a first CS-RNTI (Configured Scheduling Radio Network Temporary Identifier) ​​and links the second SPS setting with a second CS-RNTI, and the base station links the first CG setting with the first CS-RNTI and links the second CG setting with the second CS-RNTI; and the transmitting step may include a step in which the base station transmits, to the user equipment, second linking information regarding the linking of either the first SPS setting or the first CG setting with the first CS-RNTI, and third linking information regarding the linking of either the second SPS setting or the second CG setting with the second CS-RNTI.

[0121] Also, in one embodiment, (Supplementary Note 4) a communication control method in a mobile communication system, comprising the steps of a base station setting an SPS setting or a CG setting for a user device, and the base station transmitting to the user device a timing adjustment command for adjusting the start timing of a period indicated in the SPS setting or the CG setting.

[0122] (Supplementary Note 5) In the communication control method of (Supplementary Note 4) above, the start timing may be a timing at which the user equipment starts monitoring a PDCCH.

[0123] (Supplementary Note 6) In the communication control method of (Supplementary Note 4) or (Supplementary Note 5) above, the method may further include a step in which the user equipment requests the base station to adjust the reception timing or the transmission timing, and the step of transmitting the timing adjustment command may include a step in which the base station transmits the timing adjustment command to the user equipment in response to receiving the request.

[0124] 1: Mobile communication system 20: CN 100: UE 110: Receiving unit 120: Transmitting unit 130: Control unit 200: gNB 210: Transmitting unit 220: Receiving unit 230: Control unit 300: AMF

Claims

1. A communication control method in a mobile communication system, comprising: A network node performs one of linking a first SPS (Semi-Persistent Scheduling) setting and a second SPS setting having different periods, and linking a first CG (Configured Grant) setting and a second CG setting having different periods; The network node transmits, to a user equipment, first binding information regarding any one of a binding between the first SPS configuration and the second SPS configuration and a binding between the first CG configuration and the second CG configuration. Communications control method.

2. The user equipment receives a first PDSCH (Physical Downlink Shared Channel) or transmits a first PUSCH (Physical Uplink Shared Channel) by using a first radio resource included in a first PDCCH (Physical Downlink Control Channel) received at a reception timing of a first period indicated in the first SPS setting or the first CG setting for each first period, and receives a second PDSCH or transmits a second PUSCH by using a second radio resource included in a second PDCCH received at a reception timing of a second period indicated in the second SPS setting or the second CG setting for each second period. The communication control method according to claim 1.

3. The linking comprises: The network node associates the first SPS configuration with a first Configured Scheduling Radio Network Temporary Identifier (CS-RNTI) and associates the second SPS configuration with a second CS-RNTI; and The network node associates the first CG configuration with the first CS-RNTI and associates the second CG configuration with the second CS-RNTI; (c) performing any of the following: The transmitting step includes transmitting, by the network node, second binding information regarding a binding between any one of the first SPS setting and the first CG setting and the first CS-RNTI, and third binding information regarding a binding between any one of the second SPS setting and the second CG setting and the second CS-RNTI, to the user equipment. The communication control method according to claim 1.

4. A communication control method in a mobile communication system, comprising: A network node configures an SPS configuration or a CG configuration for a user equipment; The network node transmits, to the user equipment, a timing adjustment command for adjusting a start timing of a period indicated in the SPS configuration or the CG configuration. Communications control method.

5. The start timing is a timing at which the user equipment starts monitoring the PDCCH. The communication control method according to claim 4.

6. The method further comprises the user equipment requesting a timing adjustment from the network node; and transmitting the timing adjustment command includes the network node transmitting the timing adjustment command to the user equipment in response to receiving the request.

5. The communication control method according to claim 4.

7. A network node, comprising: A control unit that links a first SPS (Semi-Persistent Scheduling) setting and a second SPS setting having different periods, and links a first CG (Configured Grant) setting and a second CG setting having different periods; A transmission unit that transmits first association information regarding either an association between the first SPS setting and the second SPS setting or an association between the first CG setting and the second CG setting to a user device. Network node.

8. A network node, comprising: A control unit that sets an SPS setting or a CG setting for a user device; A transmitter that transmits a timing adjustment command to the user equipment to adjust a start timing of a period indicated in the SPS setting or the CG setting. Network node.