Communication device, base station, terminal device, and communication method

Abstract

A communication device according to the present disclosure is mounted on a terminal device. The communication device compriese a communication unit and a control unit. The communication unit receives a first packet from a transmission source of the first packet, and transmits the first packet to a transmission destination. The control unit measures a delay characteristic between the transmission of the first packet by the transmission source of the first packet to completion, by the communication unit, of transmission preparation for a second packet corresponding to the first packet, and notifies at least one of a base station and an application installed on the terminal device of delay information based on the delay characteristic.

Description

Communication device, base station, terminal device, and communication method

[0001] The present disclosure relates to a communication device, a base station, a terminal device, and a communication method.

[0002] Radio access methods and radio networks for cellular mobile communications (hereinafter also referred to as "Long Term Evolution (LTE)," "LTE-Advanced (LTE-A)," "LTE-Advanced Pro (LTE-A Pro)," "5G (fifth generation)," "New Radio (NR)," "New Radio Access Technology (NRAT)," "Evolved Universal Terrestrial Radio Access (EUTRA)," or "Further EUTRA (FEUTRA)") are being studied by the 3rd Generation Partnership Project (3GPP (registered trademark)). In the following description, LTE includes LTE-A, LTE-A Pro, and EUTRA, and NR includes NRAT and FEUTRA. In LTE and NR, a base station device (base station) is also referred to as an eNodeB (evolved NodeB) in LTE and a gNodeB in NR, and a terminal device (mobile station, mobile station device, terminal) is also referred to as a UE (User Equipment). LTE and NR are cellular communication systems in which base stations cover multiple areas in the form of cells. A single base station may manage multiple cells.

[0003] For example, Patent Document 1 discloses a technique for resolving collisions that occur when multiple UEs use uplink (UL) resources set by a Configured Grant.

[0004] Japanese Patent Application Laid-Open No. 2022-116517

[0005] In 5G, a Configured Grant is defined as a procedure for transmitting UL data. A base station can periodically allocate UL resources in advance using the Configured Grant. This allows a UE to transmit UL data without transmitting a Scheduling Request.

[0006] However, UL resources may not always be allocated at the timing when the UE wants to transmit UL data.

[0007] On the other hand, depending on the application installed in the terminal device (for example, a smartphone) in which the UE is installed, UL data requiring a small amount of delay may be generated.

[0008] Thus, there is a demand for transmitting UL data with lower delay.

[0009] Therefore, the present disclosure provides a communication device, a base station, a terminal device, and a communication method that can transmit UL data with less delay.

[0010] It should be noted that the above problem or object is merely one of multiple problems or objects that can be solved or achieved by multiple embodiments disclosed in this specification.

[0011] A communication device according to the present disclosure is installed in a terminal device. The communication device includes a communication unit and a control unit. The communication unit receives a first packet from a sender of the first packet and transmits the first packet to a destination. The control unit measures a delay characteristic from when the sender of the first packet transmits the first packet to when the communication unit completes preparations for transmitting a second packet corresponding to the first packet, and notifies at least one of a base station and an application installed in the terminal device of delay information based on the delay characteristic.

[0012] 1 is a diagram illustrating an overview of a communication system according to a proposed technique of the present disclosure. FIG. 1 is a diagram illustrating an example of a configuration of an application server according to a proposed technique of the present disclosure. FIG. 2 is a diagram illustrating an example of a configuration of an information processing device according to a proposed technique of the present disclosure. FIG. 3 is a diagram illustrating an example of a configuration of a base station according to a proposed technique of the present disclosure. FIG. 4 is a diagram illustrating an example of a configuration of a wireless communication device according to a proposed technique of the present disclosure. FIG. 5 is a diagram illustrating an example of a 5G architecture. FIG. 6 is a diagram illustrating an example of a 4G architecture. FIG. 7 is a diagram illustrating an example of a use of private / 4G. FIG. 8 is a diagram illustrating an API of a 5G core network. FIG. 9 is a diagram illustrating an API of a 5G core network. FIG. 10 is a diagram illustrating an example of a frame configuration in 5G. FIG. 11 is a diagram illustrating an example of a time frame used by a base station. FIG. 12 is a sequence diagram illustrating an example of a procedure for transmitting UL data. FIG. 13 is a sequence diagram illustrating another example of a procedure for transmitting UL data. FIG. 14 is a diagram illustrating an example of a use case of a communication system according to a first embodiment of the present disclosure. FIG. 15 is a diagram illustrating another example of a data flow according to the first embodiment of the present disclosure. FIG. 16 is a diagram illustrating an example of a use case of a communication system according to a first embodiment of the present disclosure. FIG. 17 is a diagram illustrating another example of a data flow according to the first embodiment of the present disclosure. FIG. 10 is a diagram showing another example of a data flow according to the second embodiment of the present disclosure. FIG. 11 is a sequence diagram showing an example of a communication processing flow according to the second embodiment of the present disclosure. FIG. 12 is a diagram showing an example of a data flow according to the third embodiment of the present disclosure. FIG. 13 is a sequence diagram showing an example of a communication processing flow according to the third embodiment of the present disclosure. FIG. 14 is a diagram showing an example of allocation of UL resources having burstiness. FIG. 15 is a sequence diagram showing an example of a communication processing flow according to the third embodiment of the present disclosure.

[0013] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0014] In this specification and drawings, similar components of the embodiments may be distinguished by adding different letters or numbers after the same reference numeral. However, if there is no need to particularly distinguish between the similar components, only the same reference numeral will be used.

[0015] One or more embodiments (including examples, modifications, and application examples) described below can be implemented independently. However, at least a portion of the embodiments described below may be implemented in appropriate combination with at least a portion of another embodiment. These embodiments may include novel features that are different from each other. Therefore, these embodiments may contribute to solving different purposes or problems and may produce different effects from each other.

[0016] Furthermore, although specific values ​​are sometimes used in the present specification and drawings, these values ​​are merely examples and other values ​​may also be applied.

[0017] <<1. Introduction>> <1.1. Problem> For example, an XR (Extended Reality) service can be provided via a cellular network. In the XR service, an application client installed in a Head Mounted Display (HMD) worn by a user transmits position information of the HMD, input information by the user, and the like via an uplink (UL). This information is generally about 50 bytes and is transmitted periodically.

[0018] In XR, it is known that an increase in communication delay can degrade the quality of the user experience. To reduce communication delay, it is required that UL resources are allocated at the timing when an application client wants to transmit data.

[0019] By receiving feedback on timing adjustment of UL resources from a UE mounted on the same HMD as the application client, the base station can periodically allocate UL resources at the timing when the application client wants to transmit data.

[0020] For this reason, a mechanism is required in which the UE feeds back to the base station timing adjustments based on the timing at which the application client wants to transmit data.

[0021] Although XR position information and input information are given as examples of low-latency UL data here, low-latency UL data is not limited to this. The proposed technology of the present disclosure is applicable to any UL data for which the timing at which an application client wants to send it is predetermined.

[0022] 1 is a diagram illustrating an overview of a communication system according to the proposed technology of the present disclosure. The communication system illustrated in FIG. 1 includes an application server 10, a core network CN, a base station 30, and a terminal device 400.

[0023] The communication system may support radio access technologies (RATs) such as Long Term Evolution (LTE), New Radio (NR), etc. LTE and NR are types of cellular communication technologies, and enable mobile communication of the terminal device 400 by arranging a plurality of areas covered by the base station 30 in the form of cells.

[0024] The wireless access method used by the communication system is not limited to LTE and NR, but may be other wireless access methods such as W-CDMA (Wideband Code Division Multiple Access) and CDMA2000 (Code Division Multiple Access 2000).

[0025] The terminal device 400 is an information processing device such as a mobile phone, a smart device (smartphone or tablet), a PDA (Personal Digital Assistant), or a personal computer.

[0026] The terminal device 400 is equipped with an application client 50 and a wireless communication device 40. The terminal device 400 functions as a communication device by communicating with the base station 30 via the wireless communication device 40. The terminal device 400 corresponds to, for example, the above-mentioned HMD.

[0027] The application client 50 communicates with the application server 10 via, for example, the wireless communication device 40 to receive a service (for example, an XR service) from the application server 10 .

[0028] The core network CN includes information processing devices that function as NFs.

[0029] For example, the application server 10 transmits downlink (DL) data to the application client 50 of the terminal device 400. The application client 50 transmits uplink (UL) data to the application server 10.

[0030] The wireless communication device 40 , the base station 30 and the core network CN transmit DL data or UL data to the application client 50 or the application server 10 .

[0031] As described above, low latency is required for communication between the application server 10 and the application client 50. In particular, since the UL data transmitted from the application client 50 to the application server 10 is transmitted using UL resources allocated by the base station 30, there is a risk of large latency depending on the transmission timing.

[0032] Therefore, a communication device according to the proposed technique of the present disclosure is a wireless communication device 40 mounted on a terminal device 400, and includes a communication unit and a control unit. The communication unit receives a first packet from a sender of the first packet and transmits the first packet to a destination. The control unit measures a delay characteristic from when the sender of the first packet transmits the first packet until the communication unit completes preparations for transmitting a second packet corresponding to the first packet, and notifies at least one of the base station 30 and the application client 50 mounted on the terminal device 400 of delay information based on the delay characteristic.

[0033] The sender of the packets corresponds to, for example, the base station 30 or the application client 50. When the sender of the packets is the base station 30, the first packet corresponds to DL data and the second packet corresponds to UL data. When the sender of the packets is the application client 50, both the first and second packets correspond to DL data.

[0034] The completion of the communication unit's preparation for transmission of the second packet refers to a state in which the communication unit can transmit the second packet if UL resources are available. For example, the communication unit completes preparation for transmission of the second packet when the second packet is stored in the UL transmission buffer. The second packet stored in the transmission buffer will be transmitted to the base station 30 when the UL resources are allocated.

[0035] <<2. Configuration of Communication System>> <2.1. Configuration of Application Server> The application server 10 is an information processing device that provides application services to the terminal device 400 .

[0036] Fig. 2 is a diagram showing an example configuration of an application server 10 according to the proposed technology of the present disclosure. The application server 10 includes a communication unit 11, a storage unit 12, and a control unit 13. Note that the configuration shown in Fig. 2 is a functional configuration, and the hardware configuration may be different from this.

[0037] Furthermore, the functions of the application server 10 may be statically or dynamically distributed across multiple physically separated components. For example, the application server 10 may be configured by multiple server devices.

[0038] The communication unit 11 is a communication interface for communicating with other devices. The communication unit 11 may be a network interface or a device connection interface. For example, the communication unit 11 may be a LAN (Local Area Network) interface such as a NIC (Network Interface Card), or a USB (Universal Serial Bus) interface configured by a USB host controller, a USB port, etc. The communication unit 11 may also be a wired interface or a wireless interface. The communication unit 11 functions as a communication means of the application server 10. The communication unit 11 communicates with the terminal device 400, etc., under the control of the control unit 13.

[0039] The storage unit 12 is a data readable / writable storage device such as a dynamic random access memory (DRAM), a static random access memory (SRAM), a flash memory, a hard disk, etc. The storage unit 12 functions as a storage means of the application server 10.

[0040] The control unit 13 is a controller that controls each unit of the application server 10. The control unit 13 is realized by a processor such as a central processing unit (CPU), a micro processing unit (MPU), or a graphics processing unit (GPU). For example, the control unit 13 is realized by a processor executing various programs stored in a storage device inside the application server 10 using a random access memory (RAM) or the like as a work area. The control unit 13 may also be realized by an integrated circuit such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA). The CPU, MPU, GPU, ASIC, and FPGA can all be considered controllers. The control unit 13 may also be realized by a graphics processing unit (GPU) in addition to or instead of the CPU.

[0041] 2.2. Configuration of Information Processing Device The information processing device 20 is an information processing device (computer) that manages a wireless network. For example, the information processing device 20 is a management device that manages communication of the base station 30. The information processing device 20 is a device that realizes the functions (NF) of the core network CN.

[0042] The information processing device 20 may be, for example, a device having a function as an MME (Mobility Management Entity). The information processing device 20 may be a device having a function as an AMF (Access and Mobility Management Function) and / or an SMF (Session Management Function). Of course, the functions of the information processing device 20 are not limited to an MME, an AMF, and an SMF. The information processing device 20 may be a device having a function as an NSSF (Network Slice Selection Function), an AUSF (Authentication Server Function), a PCF (Policy Control Function), or a UDM (Unified Data Management). Furthermore, the information processing device 20 may be a device having a function as an HSS (Home Subscriber Server).

[0043] The information processing device 20 may have a gateway function. For example, the information processing device 20 may have a function as an S-GW (Serving Gateway) or a P-GW (Packet Data Network Gateway). The information processing device 20 may also have a UPF (User Plane Function) function. In this case, the information processing device 20 may have multiple UPFs. The information processing device 20 may also have a PNAM (Private Network Association Management) function.

[0044] The core network CN is composed of multiple network functions, and each network function may be aggregated in one physical device or distributed across multiple physical devices. That is, the information processing device 20 may be distributed across multiple devices. Furthermore, this distributed distribution may be controlled to be executed dynamically. The base station 30 and the information processing device 20 form a single network, providing wireless communication services to the terminal device 400. The information processing device 20 is connected to the Internet, and the terminal device 400 can use various services provided via the Internet via the base station 30.

[0045] The information processing device 20 does not necessarily have to be a device that constitutes the core network CN. For example, assume that the core network is a W-CDMA (Wideband Code Division Multiple Access) or cdma2000 (Code Division Multiple Access 2000) core network. In this case, the information processing device 20 may be a device that functions as an RNC (Radio Network Controller).

[0046] FIG. 3 is a diagram showing an example configuration of an information processing device 20 according to the proposed technology of the present disclosure. The information processing device 20 includes a communication unit 21, a storage unit 22, and a control unit 23. Note that the configuration shown in FIG. 3 is a functional configuration, and the hardware configuration may be different. Furthermore, the functions of the information processing device 20 may be statically or dynamically distributed and implemented in multiple physically separated configurations. For example, the information processing device 20 may be configured by multiple server devices.

[0047] The communication unit 21 is a communication interface for communicating with other devices. The communication unit 21 may be a network interface or a device connection interface. For example, the communication unit 21 may be a LAN (Local Area Network) interface such as a NIC (Network Interface Card), or a USB (Universal Serial Bus) interface configured by a USB host controller, a USB port, etc. The communication unit 21 may also be a wired interface or a wireless interface. The communication unit 21 functions as a communication means of the information processing device 20. The communication unit 21 communicates with the base station 30, etc., under the control of the control unit 23.

[0048] The storage unit 22 is a data readable / writable storage device such as a DRAM, an SRAM, a flash memory, a hard disk, etc. The storage unit 22 functions as a storage means of the information processing device 20.

[0049] The control unit 23 is a controller that controls each unit of the information processing device 20. The control unit 23 is realized by a processor such as a CPU, an MPU, or a GPU. For example, the control unit 23 is realized by a processor executing various programs stored in a storage device inside the information processing device 20 using RAM or the like as a work area. The control unit 23 may also be realized by an integrated circuit such as an ASIC or an FPGA. A CPU, an MPU, a GPU, an ASIC, and an FPGA can all be considered as controllers. The control unit 23 may also be realized by a GPU in addition to or instead of a CPU.

[0050] 2.3. Configuration of Base Station The base station 30 is a wireless communication device that performs wireless communication with the terminal device 400 (wireless communication device 40). The base station 30 may be configured to perform wireless communication with the wireless communication device 40 via a relay station, or may be configured to perform wireless communication directly with the wireless communication device 40.

[0051] The base station 30 is a type of communication device. More specifically, the base station 30 is a device equivalent to a radio base station (e.g., base station, Node B, eNB, gNB, etc.) or a radio access point (Access Point). The base station 30 may be a radio relay station. The base station 30 may also be an optical device called an RRH (Remote Radio Head) or an RU (Radio Unit). The base station 30 may also be a receiving station such as an FPU (Field Pickup Unit). The base station 30 may also be an IAB (Integrated Access and Backhaul) donor node or an IAB relay node that provides radio access lines and radio backhaul lines using time division multiplexing, frequency division multiplexing, or space division multiplexing.

[0052] The wireless access technology used by the base station 30 may be cellular communication technology or wireless LAN technology. Of course, the wireless access technology used by the base station 30 is not limited to these and may be other wireless access technologies. For example, the wireless access technology used by the base station 30 may be low-power wide-area (LPWA) communication technology. Of course, the wireless communication used by the base station 30 may be wireless communication using millimeter waves. Furthermore, the wireless communication used by the base station 30 may be wireless communication using radio waves or wireless communication using infrared or visible light (optical wireless). Furthermore, the base station 30 may be capable of NOMA (Non-Orthogonal Multiple Access) communication with wireless communication devices. Here, NOMA communication refers to communication (transmission, reception, or both) using non-orthogonal resources. Furthermore, the base station 30 may be capable of NOMA communication with other base stations 30.

[0053] The base stations 30 may be able to communicate with each other via a base station-core network interface (e.g., NG Interface, S1 Interface, etc.). This interface may be either wired or wireless. The base stations 30 may be able to communicate with each other via an inter-base station interface (e.g., Xn Interface, X2 Interface, S1 Interface, F1 Interface, etc.). This interface may be either wired or wireless.

[0054] The concept of a base station includes not only a donor base station but also a relay base station (also called a relay station). For example, a relay base station may be any one of an RF Repeater, a Smart Repeater, and an Intelligent Surface. The concept of a base station also includes not only a structure having base station functions but also a device installed in the structure.

[0055] Examples of structures include high-rise buildings, houses, steel towers, station facilities, airport facilities, port facilities, office buildings, school buildings, hospitals, factories, commercial facilities, stadiums, and other buildings. The concept of a structure includes not only buildings, but also non-building structures such as tunnels, bridges, dams, fences, and steel pillars, as well as equipment such as cranes, gates, and wind turbines. The concept of a structure also includes not only land (ground in the narrow sense) or underground structures, but also water-based structures such as piers and megafloats, and underwater structures such as ocean observation facilities. A base station can be rephrased as an information processing device.

[0056] The base station 30 may be a donor station or a relay station (relay station). The base station 30 may also be a fixed station or a mobile station. A mobile station is a wireless communication device (e.g., a base station) configured to be mobile. In this case, the base station 30 may be a device installed in a mobile body, or may be the mobile body itself. For example, a relay station with mobility can be considered a base station 30 as a mobile station. Furthermore, devices that are inherently mobile and have base station functionality (at least part of the base station functionality), such as vehicles, UAVs (Unmanned Aerial Vehicles) represented by drones, and smartphones, also fall under the category of a base station 30 as a mobile station.

[0057] Here, the mobile body may be a mobile terminal such as a smartphone or a mobile phone. The mobile body may also be a mobile body that moves on land (ground in the narrow sense) (e.g., vehicles such as automobiles, bicycles, buses, trucks, motorcycles, trains, and linear motor cars), or a mobile body that moves underground (e.g., in a tunnel) (e.g., a subway). The mobile body may also be a mobile body that moves on water (e.g., ships such as passenger ships, cargo ships, and hovercraft), or a mobile body that moves underwater (e.g., submersibles such as submarines, submarines, and unmanned underwater vehicles). The mobile body may also be a mobile body that moves within the atmosphere (e.g., aircraft such as airplanes, airships, and drones).

[0058] The base station 30 may also be a terrestrial base station (ground station) installed on the ground. For example, the base station 30 may be a base station located on a structure on the ground, or a base station installed on a mobile object moving on the ground. More specifically, the base station 30 may be an antenna installed on a structure such as a building and a signal processing device connected to the antenna. Of course, the base station 30 may also be the structure or mobile object itself. "Ground" refers not only to land (ground in the narrow sense) but also to ground, on water, and underwater. Note that the base station 30 is not limited to a terrestrial base station. For example, if the communication system is a satellite communication system, the base station 30 may be an aircraft station. From the perspective of the satellite station, an aircraft station located on Earth is a ground station.

[0059] The base station 30 is not limited to a terrestrial station. The base station 30 may be a non-terrestrial base station (non-terrestrial station) that can fly in the air or space. For example, the base station 30 may be an aircraft station or a satellite station.

[0060] A satellite station is a satellite station capable of floating outside the atmosphere. The satellite station may be a device mounted on a space vehicle such as an artificial satellite, or may be the space vehicle itself. A space vehicle is a vehicle that moves outside the atmosphere. Examples of space vehicles include artificial celestial bodies such as artificial satellites, spacecraft, space stations, and probes. Note that a satellite that serves as a satellite station may be any of a low Earth orbiting (LEO) satellite, a medium Earth orbiting (MEO) satellite, a geostationary Earth orbiting (GEO) satellite, and a highly elliptical orbiting (HEO) satellite. Of course, the satellite station may be a device mounted on a low Earth orbiting (LEO), medium Earth orbiting (MEO), geostationary satellite, or highly elliptical orbiting (HEO) satellite.

[0061] An aircraft station is a wireless communication device capable of floating in the atmosphere, such as an aircraft. The aircraft station may be a device mounted on the aircraft, or may be the aircraft itself. The concept of aircraft includes not only heavier-than-air vehicles such as airplanes and gliders, but also lighter-than-air vehicles such as balloons and airships. The concept of aircraft also includes not only heavier-than-air vehicles and lighter-than-air vehicles, but also rotorcraft such as helicopters and autogyros. The aircraft station (or an aircraft on which the aircraft station is mounted) may be an unmanned aerial vehicle such as a drone.

[0062] The concept of unmanned aerial vehicles also includes unmanned aerial systems (UAS) and tethered unmanned aerial systems (TAS). The concept of unmanned aerial vehicles also includes lighter than air UAS (LTA) and heavier than air UAS (HTA). The concept of unmanned aerial vehicles also includes high altitude unmanned aerial system platforms (HAPs).

[0063] The size of the coverage of the base station 30 may be as large as a macrocell or as small as a picocell. Of course, the size of the coverage of the base station 30 may also be extremely small, such as a femtocell. The base station 30 may also have beamforming capabilities. In this case, the base station 30 may form a cell or service area for each beam.

[0064] Fig. 4 is a diagram showing an example configuration of a base station 30 according to the proposed technique of the present disclosure. The base station 30 includes a wireless communication unit 31, a storage unit 32, and a control unit 33. Note that the configuration shown in Fig. 4 is a functional configuration, and the hardware configuration may be different from this. Furthermore, the functions of the base station 30 may be distributed and implemented in multiple physically separated units.

[0065] The wireless communication unit 31 is a signal processing unit for wireless communication with other wireless communication devices (for example, wireless communication devices). The wireless communication unit 31 operates under the control of the control unit 33. The wireless communication unit 31 supports one or more wireless access methods. For example, the wireless communication unit 31 supports both NR and LTE. The wireless communication unit 31 may support W-CDMA and cdma2000 in addition to NR and LTE. Furthermore, the wireless communication unit 31 may support an automatic retransmission technique such as HARQ (Hybrid Automatic Repeat reQuest).

[0066] The wireless communication unit 31 includes a transmission processing unit 311, a reception processing unit 312, and an antenna 313. The wireless communication unit 31 may include a plurality of transmission processing units 311, a reception processing unit 312, and an antenna 313. When the wireless communication unit 31 supports a plurality of wireless access methods, each unit of the wireless communication unit 31 may be configured separately for each wireless access method. For example, the transmission processing unit 311 and the reception processing unit 312 may be configured separately for LTE and NR. The antenna 313 may also be configured with a plurality of antenna elements (e.g., a plurality of patch antennas). In this case, the wireless communication unit 31 may be configured to be capable of beamforming. The wireless communication unit 31 may be configured to be capable of polarization beamforming using vertically polarized waves (V polarization) and horizontally polarized waves (H polarization).

[0067] The transmission processing unit 311 performs transmission processing of the downlink control information and downlink data. For example, the transmission processing unit 311 encodes the downlink control information and downlink data input from the control unit 33 using a coding method such as block coding, convolutional coding, or turbo coding. Here, the encoding may be performed using polar codes or low density parity check codes (LDPC codes). The transmission processing unit 311 then modulates the coded bits using a predetermined modulation method such as BPSK, QPSK, 16QAM, 64QAM, or 256QAM. In this case, the signal points on the constellation do not necessarily need to be equidistant. The constellation may be a non-uniform constellation (NUC). The transmission processing unit 311 then multiplexes the modulation symbols of each channel and the downlink reference signal and allocates them to predetermined resource elements. The transmission processing unit 311 then performs various signal processing on the multiplexed signal. For example, the transmission processing unit 311 performs processes such as conversion to the frequency domain by fast Fourier transform, addition of a guard interval (cyclic prefix), generation of a baseband digital signal, conversion to an analog signal, quadrature modulation, up-conversion, removal of unnecessary frequency components, power amplification, etc. The signal generated by the transmission processing unit 311 is transmitted from an antenna 313.

[0068] The reception processing unit 312 processes the uplink signal received via the antenna 313. For example, the reception processing unit 312 performs downconversion, removal of unnecessary frequency components, control of amplification level, quadrature demodulation, conversion to a digital signal, removal of guard intervals (cyclic prefixes), extraction of frequency domain signals by fast Fourier transform, and the like on the uplink signal. The reception processing unit 312 then separates uplink channels such as a PUSCH (Physical Uplink Shared Channel) and a PUCCH (Physical Uplink Control Channel) and an uplink reference signal from the signal that has undergone these processes. The reception processing unit 312 also demodulates the received signal using a modulation method such as Binary Phase Shift Keying (BPSK) or Quadrature Phase Shift Keying (QPSK) for the modulation symbols of the uplink channel. The modulation method used for demodulation may be 16QAM (Quadrature Amplitude Modulation), 64QAM, or 256QAM. In this case, the signal points on the constellation do not necessarily have to be equidistant. The constellation may be a non-uniform constellation (NUC). The reception processing unit 312 then performs decoding processing on the coded bits of the demodulated uplink channel. The decoded uplink data and uplink control information are output to the control unit 33.

[0069] The antenna 313 is an antenna device (antenna unit) that converts electric current and radio waves into each other. The antenna 313 may be composed of one antenna element (e.g., one patch antenna) or multiple antenna elements (e.g., multiple patch antennas). When the antenna 313 is composed of multiple antenna elements, the wireless communication unit 31 may be configured to be capable of beamforming. For example, the wireless communication unit 31 may be configured to generate a directional beam by controlling the directivity of a wireless signal using multiple antenna elements. The antenna 313 may be a dual-polarized antenna. When the antenna 313 is a dual-polarized antenna, the wireless communication unit 31 may use vertically polarized waves (V polarization) and horizontally polarized waves (H polarization) to transmit a wireless signal. The wireless communication unit 31 may then control the directivity of the wireless signal transmitted using the vertically polarized waves and the horizontally polarized waves. The wireless communication unit 31 may also transmit and receive spatially multiplexed signals via multiple layers composed of multiple antenna elements.

[0070] The storage unit 32 is a data readable / writable storage device such as a DRAM, an SRAM, a flash memory, a hard disk, etc. The storage unit 32 functions as a storage means of the base station 30.

[0071] The control unit 33 is a controller that controls each unit of the base station 30. The control unit 33 is realized by a processor such as a CPU or an MPU. For example, the control unit 33 is realized by a processor executing various programs stored in a storage device inside the base station 30 using RAM or the like as a work area. The control unit 33 may also be realized by an integrated circuit such as an ASIC or an FPGA. A CPU, an MPU, an ASIC, and an FPGA can all be considered as controllers. The control unit 33 may also be realized by a GPU in addition to or instead of a CPU.

[0072] In the proposed technology, the concept of a base station may be composed of a collection of multiple physical or logical devices. For example, in the proposed technology, a base station may be divided into multiple devices such as a baseband unit (BBU) and a radio unit (RU). The base station may be interpreted as a collection of these multiple devices. Furthermore, a base station may be either a BBU or an RU, or both. The BBU and the RU may be connected via a predetermined interface (e.g., an enhanced Common Public Radio Interface (eCPRI)). The RU may also be referred to as a remote radio unit (RRU) or a radio DoT (RD). The RU may correspond to a gNB distributed unit (gNB-DU) described later. Furthermore, the BBU may correspond to a gNB central unit (gNB-CU) described later. Alternatively, the RU may be a radio device connected to a gNB-DU described later. The gNB-CU, gNB-DU, and RU connected to the gNB-DU may be configured to comply with O-RAN (Open Radio Access Network). Furthermore, the RU may be a device integrally formed with an antenna. The antenna of the base station (e.g., an antenna integrally formed with the RU) may employ an Advanced Antenna System and support MIMO (e.g., FD-MIMO) and beamforming. Furthermore, the antenna of the base station may have, for example, 64 transmitting antenna ports and 64 receiving antenna ports.

[0073] The antenna mounted on the RU may be an antenna panel composed of one or more antenna elements, and the RU may be equipped with one or more antenna panels. For example, the RU may be equipped with two types of antenna panels, one for horizontal polarization and one for vertical polarization, or two types of antenna panels, one for right-handed circular polarization and one for left-handed circular polarization. The RU may also form and control independent beams for each antenna panel.

[0074] It should be noted that multiple base stations may be connected to each other. One or more base stations may be included in a radio access network (RAN). In this case, the base station may simply be referred to as a RAN, a RAN node, an AN (Access Network), or an AN node. It should be noted that the RAN in LTE may be called an Enhanced Universal Terrestrial RAN (EUTRAN). The RAN in NR may be called an NGRAN. The RAN in W-CDMA (UMTS) may be called a UTRAN.

[0075] Note that an LTE base station may be referred to as an eNodeB (Evolved Node B) or eNB. In this case, the EUTRAN includes one or more eNodeBs (eNBs). Also, an NR base station may be referred to as a gNodeB or gNB. In this case, the NGRAN includes one or more gNBs. The EUTRAN may include a gNB (en-gNB) connected to a core network (EPC) in an LTE communication system (EPS). Similarly, the NGRAN may include an ng-eNB connected to a core network 5GC in a 5G communication system (5GS).

[0076] When the base station is an eNB, gNB, or the like, the base station may be referred to as a 3GPP access. When the base station is a wireless access point, the base station may be referred to as a non-3GPP access. Furthermore, the base station may be an optical extension device called an RRH (Remote Radio Head) or an RU (Radio Unit). When the base station is a gNB, the base station may be a combination of the above-mentioned gNB-CU and gNB-DU, or may be either a gNB-CU or a gNB-DU.

[0077] Here, the gNB-CU hosts multiple upper layers (e.g., RRC (Radio Resource Control), SDAP (Service Data Adaptation Protocol), PDCP (Packet Data Convergence Protocol)) of the access stratum for communication with the UE. On the other hand, the gNB-DU hosts multiple lower layers (e.g., RLC (Radio Link Control), MAC (Medium Access Control), PHY (Physical layer)) of the access stratum. That is, among the messages / information described below, RRC signaling (semi-static notification) is generated by the gNB-CU, while MAC The CE and DCI (dynamic notification) may be generated by the gNB-DU. Alternatively, some configurations of the RRC configuration (semi-static notification), such as IE:cellGroupConfig, may be generated by the gNB-DU, and the remaining configurations may be generated by the gNB-CU. These configurations may be transmitted and received over the F1 interface described below.

[0078] Note that a base station may be configured to be able to communicate with other base stations. For example, if multiple base stations are eNBs or a combination of an eNB and an en-gNB, the base stations may be connected via an X2 interface. Also, if multiple base stations are gNBs or a combination of a gn-eNB and a gNB, the devices may be connected via an Xn interface. Also, if multiple base stations are a combination of a gNB-CU and a gNB-DU, the devices may be connected via the above-mentioned F1 interface. Messages / information (e.g., RRC signaling, MAC CE (MAC Control Element), or DCI) described below may be transmitted between multiple base stations, for example, via an X2 interface, an Xn interface, or an F1 interface.

[0079] A cell provided by a base station may be referred to as a serving cell. The concept of a serving cell includes a PCell (Primary Cell) and an SCell (Secondary Cell). When dual connectivity is configured in a UE (e.g., a wireless communication device), the PCell and zero or more SCells provided by a Master Node (MN) may be referred to as a Master Cell Group. Examples of dual connectivity include EUTRA-EUTRA Dual Connectivity, EUTRA-NR Dual Connectivity (ENDC), EUTRA-NR Dual Connectivity with 5GC, NR-EUTRA Dual Connectivity (NEDC), and NR-NR Dual Connectivity.

[0080] The serving cell may include a PSCell (Primary Secondary Cell or Primary SCG Cell). When dual connectivity is configured for a UE, the PSCell and zero or more SCells provided by a Secondary Node (SN) may be referred to as a Secondary Cell Group (SCG). Unless special configuration (e.g., PUCCH on SCell) is performed, the physical uplink control channel (PUCCH) is transmitted by the PCell and PSCell but not by the SCell. In addition, radio link failure is detected by the PCell and PSCell but not by the SCell (it does not need to be detected). As such, the PCell and PSCell have special roles among serving cells and are therefore also referred to as Special Cells (SpCells).

[0081] One cell may be associated with one downlink component carrier and one uplink component carrier. Furthermore, the system bandwidth corresponding to one cell may be divided into a plurality of BWPs (Bandwidth Parts). In this case, one or a plurality of BWPs may be configured in a UE, and one BWP may be used by the UE as an active BWP. Furthermore, the radio resources (e.g., frequency band, numerology (subcarrier spacing), slot format) that can be used by a wireless communication device may differ for each cell, each component carrier, or each BWP.

[0082] 2.4. Configuration of Wireless Communication Device Next, a description will be given of the configuration of the wireless communication device 40. The wireless communication device 40 can also be referred to as UE (User Equipment) 40.

[0083] The wireless communication device 40 is a communication device that wirelessly communicates with other communication devices such as the base station 30. The wireless communication device 40 is, for example, a mobile phone, a smart device (smartphone or tablet), a personal digital assistant (PDA), or a personal computer. The wireless communication device 40 may also be a device such as a commercial camera equipped with a communication function, or a motorcycle or mobile broadcast vehicle equipped with a communication device such as a field pickup unit (FPU). The wireless communication device 40 may also be an M2M (Machine to Machine) device or an IoT (Internet of Things) device.

[0084] The wireless communication device 40 may be capable of NOMA communication with the base station 30. Furthermore, the wireless communication device 40 may use an automatic repeat transmission technique such as HARQ when communicating with the base station 30. The wireless communication device 40 may be capable of sidelink communication with other wireless communication devices 40. The wireless communication device 40 may also use an automatic repeat transmission technique such as HARQ when performing sidelink communication. The wireless communication device 40 may also be capable of NOMA communication in communication (sidelink) with other wireless communication devices 40. The wireless communication device 40 may also be capable of LPWA communication with other communication devices (e.g., base stations 30 and other wireless communication devices 40). The wireless communication used by the wireless communication device 40 may be wireless communication using millimeter waves. The wireless communication (including sidelink communication) used by the wireless communication device 40 may be wireless communication using radio waves, or wireless communication using infrared or visible light (optical wireless).

[0085] The wireless communication device 40 may also be mounted on a mobile device. The mobile device is a mobile wireless communication device. For example, the wireless communication device 40 may be a vehicle that moves on a road, such as an automobile, bus, truck, or motorcycle, a vehicle that moves on rails installed on a track, such as a train, or a wireless communication device mounted on such a vehicle. The mobile device may be a mobile terminal, or a mobile device that moves on land (ground in the narrow sense), underground, on water, or underwater. The mobile device may also be a mobile device that moves within the atmosphere, such as a drone or helicopter, or a mobile device that moves outside the atmosphere, such as an artificial satellite.

[0086] The wireless communication device 40 may simultaneously connect to and communicate with multiple base stations or multiple cells. For example, when one base station supports a communication area through multiple cells (e.g., pCell, sCell), the multiple cells can be aggregated using carrier aggregation (CA), dual connectivity (DC), or multi-connectivity (MC) technology to enable communication between the base station 30 and the wireless communication device 40. Alternatively, the wireless communication device 40 can communicate with the multiple base stations 30 via cells of different base stations 30 using coordinated multi-point transmission and reception (CoMP).

[0087] Fig. 5 is a diagram showing an example configuration of a wireless communication device 40 according to the proposed technique of the present disclosure. The wireless communication device 40 includes a wireless communication unit 41, a storage unit 42, and a control unit 43. Note that the configuration shown in Fig. 5 is a functional configuration, and the hardware configuration may be different from this. Furthermore, the functions of the wireless communication device 40 may be distributed and implemented in multiple physically separated components.

[0088] The wireless communication unit 41 is a signal processing unit for wirelessly communicating with other wireless communication devices (e.g., the base station 30 and other wireless communication devices 40). The wireless communication unit 41 operates under the control of the control unit 43. The wireless communication unit 41 includes a transmission processing unit 411, a reception processing unit 412, and an antenna 413. The configurations of the wireless communication unit 41, the transmission processing unit 411, the reception processing unit 412, and the antenna 413 may be similar to those of the wireless communication unit 31, the transmission processing unit 311, the reception processing unit 312, and the antenna 313 of the base station 30. Furthermore, like the wireless communication unit 31, the wireless communication unit 41 may be configured to be capable of beamforming. Furthermore, like the wireless communication unit 31, the wireless communication unit 41 may be configured to be capable of transmitting and receiving spatially multiplexed signals.

[0089] The storage unit 42 is a data readable / writable storage device such as a DRAM, an SRAM, a flash memory, a hard disk, etc. The storage unit 42 functions as a storage means of the wireless communication device 40.

[0090] The control unit 43 is a controller that controls each unit of the wireless communication device 40. The control unit 43 is realized by a processor such as a CPU or an MPU. For example, the control unit 43 is realized by a processor executing various programs stored in a storage device inside the wireless communication device 40 using RAM or the like as a work area. The control unit 43 may also be realized by an integrated circuit such as an ASIC or an FPGA. A CPU, an MPU, an ASIC, and an FPGA can all be considered as controllers. The control unit 43 may also be realized by a GPU in addition to or instead of a CPU.

[0091] <<3. Network Overview>> <3.1. Example of 5G Network Architecture Configuration> As an example of the core network CN of a communication system, the architecture of a fifth-generation mobile communication system (5G) will be described.

[0092] 6 is a diagram illustrating an example of a 5G architecture. The 5G core network CN is also called 5GC (5G Core) / NGC (Next Generation Core). Hereinafter, the 5G core network CN is also referred to as 5GC / NGC.

[0093] The core network CN is connected to a UE (User Equipment) 40 via an (R)AN 30. The UE 40 is, for example, a wireless communication device 40.

[0094] Although the core network CN shown in Fig. 6 does not include a management function (PNAM) for managing multiple private networks, the core network CN may include a PNAM as one of its network functions. Of course, the PNAM may be a network function located outside the core network CN.

[0095] The (R)AN 30 has a function that enables connection with a Radio Access Network (RAN) and connection with an Access Network (AN) other than the RAN. The (R)AN 30 includes a base station called a gNB or ng-eNB.

[0096] The core network CN mainly performs connection permission and session management when the UE 40 connects to the network. The core network CN can be configured to include a user plane function group 220 and a control plane function group 240.

[0097] The user plane function group 220 includes a User Plane Function (UPF) 221 and a Data Network (DN) 222. The UPF 221 has a function of processing the user plane. The UPF 221 includes a function of routing / forwarding data handled in the user plane. The DN 222 is, for example, an entity such as an MNO (Mobile Network Operator) that provides connection to an operator's own services, provides Internet connection, or provides connection to third-party services. In this way, the user plane function group 220 plays the role of a gateway that serves as the boundary between the core network CN and the Internet.

[0098] The control plane function group 240 includes an Access Management Function (AMF) 241, a Session Management Function (SMF) 242, an Authentication Server Function (AUSF) 243, a Network Slice Selection Function (NSSF) 244, a Network Exposure Function (NEF) 245, a Network Repository Function (NRF) 246, a Policy Control Function (PCF) 247, a Unified Data Management (UDM) 248, and an Application Function (AF) 249.

[0099] The AMF 241 has functions such as registration processing, connection management, and mobility management for the UE 40. The SMF 242 has functions such as session management, IP allocation and management for the UE 40, etc. The AUSF 243 has an authentication function. The NSSF 244 has a function related to network slice selection. The NEF 245 has a function of providing network function capabilities and events to third parties, the AF 249, and edge computing functions.

[0100] The NRF 246 has a function of discovering network capabilities and maintaining network capability profiles. The PCF 247 has a function of policy control. The UDM 248 has a function of generating 3GPP AKA authentication information and processing user IDs. The AF 249 has a function of interacting with the core network to provide services.

[0101] For example, the control plane function group 240 acquires information from the UDM 248, which stores subscriber information of the UE 40, and determines whether or not the UE 40 may connect to the network. For this determination, the control plane function group 240 uses the contract information of the UE 40 and an encryption key contained in the information acquired from the UDM 248. The control plane function group 240 also generates encryption keys and the like.

[0102] That is, the control plane function group 240 determines whether or not the UE 40 can connect to the network depending on whether or not information about the UE 40 linked to a subscriber number called an IMSI (International Mobile Subscriber Identity) is stored in the UDM 248. The IMSI is stored in a SIM (Subscriber Identity Module) card in the UE 40, for example.

[0103] Here, Namf is a service-based interface provided by the AMF 241, and Nsmf is a service-based interface provided by the SMF 242. Furthermore, Nnef is a service-based interface provided by the NEF 245, and Npcf is a service-based interface provided by the PCF 247. Nudm is a service-based interface provided by the UDM 248, and Naf is a service-based interface provided by the AF 249. Nnrf is a service-based interface provided by the NRF 246, and Nnssf is a service-based interface provided by the NSSF 244. Nausf is a service-based interface provided by the AUSF 243. Each of these NFs (Network Functions) exchanges information with other NFs via the respective service-based interfaces.

[0104] 6, N1 is a reference point between the UE 40 and the AMF 241, and N2 is a reference point between the RAN / AN 30 and the AMF 241. N4 is a reference point between the SMF 242 and the UPF 221, and information is exchanged between these NFs (Network Functions).

[0105] As described above, the core network CN provides an interface for transmitting information and controlling functions via an application programming interface (API) called a service-based interface.

[0106] The API allows a resource to be specified, and enables operations such as GET (obtaining a resource), POST (creating a resource or adding data), PUT (creating a resource or updating a resource), and DELETE (deleting a resource) to that resource. Such functions are commonly used in, for example, web-related technical fields.

[0107] For example, when establishing a communication session, the AMF 241, the SMF 242, and the UDM 248 shown in Fig. 6 exchange information with each other using APIs. Conventionally, it has not been assumed that an application (e.g., the AF 249) would use such an API. However, by the AF 249 using such an API, the AF 249 can use information on a 5G cellular network, which is considered to further evolve the functionality of the application.

[0108] An example of the UE 40 in Fig. 6 is the wireless communication device 40 of the proposed technology. An example of the (R)AN 30 is the base station 30 of the proposed technology. Furthermore, the information processing device 20 is an example of a device having each function of the core network CN. The application server 10 may be the AF 249 in Fig. 6 or a server device connected to the core network CN via a network other than the core network CN.

[0109] In the proposed technology, for example, wireless communication is performed between the (R)AN 30 and the UE 40. To perform wireless communication, the (R)AN 30 and the UE 40 need a technique for performing modulation and demodulation.

[0110] Furthermore, in wireless communication, resource allocation, that is, allocation of limited time resources and frequency resources to the UE 40, is important.

[0111] Time resources are configured as frames. For example, in a 5G system, one frame is configured with 10 ms. Furthermore, one frame is configured with 10 subframes. Each subframe is configured with multiple Orthogonal Frequency Division Multiplexing (OFDM) symbols. The OFDM symbols include, for example, DL OFDM symbols and UL OFDM symbols.

[0112] A basic unit of a frequency band called a Component Carrier is used as a frequency resource. A Component Carrier has a bandwidth of 20 MHz. A frequency band formed by aggregating multiple Component Carriers can be used as a frequency resource.

[0113] <3.2.4G Network Architecture Configuration Example> Next, the architecture of a fourth generation mobile communication system (4G) will be described as an example of a core network CN of a communication system with reference to Fig. 7. Fig. 7 is a diagram showing an example of the 4G architecture.

[0114] Although the core network CN shown in Fig. 7 does not include a management function (PNAM) for managing multiple private networks, the core network CN may include a PNAM as one of its network functions. Of course, the PNAM may be a network function located outside the core network CN.

[0115] As shown in FIG. 7, the core network CN includes an eNB 30, a Mobility Management Entity (MME) 252, a Serving Gateway (S-GW) 253, a Packet Data Network Gateway (P-GW) 254, and a Home Subscriber Server (HSS) 255.

[0116] The eNB 30 functions as a 4G base station. The MME 252 is a control node that handles control plane signals and manages the mobility state of the UE 40. The UE 40 transmits an Attach request to the MME 252 in order to attach to the cellular system.

[0117] The S-GW 253 is a control node that handles user plane signals and is a gateway device that switches the transfer path of user data. The P-GW 254 is a control node that handles user plane signals and is a gateway device that serves as a connection point between the core network CN and the Internet. The HSS 255 is a control node that handles subscriber data and performs service control.

[0118] The MME 252 corresponds to the functions of the AMF 241 and the SMF 242 in a 5G network. The HSS 255 corresponds to the function of the UDM 248.

[0119] 7, the eNB 30 is connected to the MME 252 via an S1-MME interface and to the S-GW 253 via an S1-U interface. The S-GW 253 is connected to the MME 252 via an S11 interface, and the MME 252 is connected to the HSS 255 via an S6a interface. The P-GW 254 is connected to the S-GW 253 via an S5 / S8 interface.

[0120] <3.3. Private Networks (Private 5G / 4G)> A communication system according to the proposed technology of the present disclosure is a system that realizes low-latency communication. When considering a low-latency system, a private network is one candidate.

[0121] Private networks allow communication systems to be easily customized to fit specific applications, making them a popular choice when configuring systems with low latency and / or low jitter (small latency fluctuations).

[0122] Therefore, an overview of private networks will be described below. In particular, in technologies that aim to integrate applications and cellular technologies, it may be desirable to adopt private networks from the perspective of being able to freely change the design. However, the proposed technology of this disclosure is not limited to private networks and can also be applied to public networks.

[0123] Currently, many offices and homes have LANs (Local Area Networks). LANs are composed of LAN cables, routers, and the like. Communication devices are connected to ISPs (Internet Service Providers) via the LAN. Private 5G and Private 4G are networks that are operated by placing cellular base stations 30 on these LANs. In 3GPP (registered trademark), Private 5G / 4G are called Non-Public Networks.

[0124] In private 5G / 4G, the base station 30 and the wireless communication device 40 are located, for example, in an office, factory, or private home where a LAN is installed. On the other hand, the core network CN that controls the base station 30 may be located in the LAN or in a cloud data center on the Internet. The base station 30 and the core network CN are assigned private IP addresses and can communicate with each other. For example, the base station 30 and the core network CN can communicate with each other using private IP addresses by using technology such as a virtual private network. As a result, the network connecting the base station 30 and the core network CN can be treated as a private network.

[0125] Figure 8 is a diagram showing an example of the use of private 5G / 4G. In the example of Figure 8, a plurality of user plane functions (UPFs) of the core network CN are deployed in the LAN and the cloud, and the control plane function of the core network CN is deployed in the cloud. Also, in the example of Figure 8, the base station 30 and the UE 40 are deployed in the LAN area.

[0126] Private 5G / 4G is a non-public network. In private 5G / 4G, it is often assumed that the UE 40, base station 30, core network CN, and applications are located inside a virtual private network. In this case, for example, the UE 40 and base station 30 may be located in a LAN area. Furthermore, the core network CN and applications may be located either in the LAN area or in a cloud in the Internet.

[0127] At least one UPF deployed in the LAN exists in the LAN when the control plane function is launched or when the core network CN starts operating. On the other hand, at least one UPF deployed in the cloud does not exist in the cloud when the control plane function is launched or when the core network CN starts operating. The UPF deployed in the cloud is a function that is launched after the control plane function is launched or when the core network CN starts operating, for example.

[0128] <3. Regarding API of 4.5G Core Network> For example, information may be transmitted from the application client 50 installed in the terminal device 400 via an API (Application Programming Interface) called SBI (Service Based Interface) installed in the base station 30.

[0129] In the following, as an example of this SBI, we will explain the SBI provided in the core network CN, but a similar SBI is also provided in the base station 30, and the application client 50 can communicate with the base station 30 using this SBI.

[0130] As mentioned above, the 5G core network (CN) provides an API called SBI. Communication devices transmit information and control functions via this API.

[0131] FIG. 9 is a diagram for explaining the API of the 5G core network. The API enables the specification of a resource, and GET (resource acquisition), POST (resource creation, data addition), PUT (resource creation, resource update), DELETE (resource deletion), and the like for that resource. Such functions are technologies commonly used in the web world. The AMF, SMF, and UDM in the diagram need to exchange information with each other when establishing a communication session. The AMF, SMF, and UDM exchange this information via the API.

[0132] Most of these APIs are not intended for use by applications. However, it is believed that by using these APIs, applications can perform more advanced information processing using cellular network information. Applications are not permitted to use APIs without permission in public networks. However, in private 5G, which is a non-public network, it is possible to use APIs, including modifying the APIs of the core network (CN).

[0133] <3.5.5G Core Network API Example> Figure 10 is a diagram for explaining the API of the 5G core network. In the example of Figure 10, the base station 30 and the core network CN are arranged in a virtual LAN (virtual LAN). The base station 30 and the core network CN communicate with the Internet outside the virtual LAN via a router. In Figure 10, UE 40A and UE 40B communicate. Note that APIs (1) to (4) described here are described in 3GPP TS23.502.

[0134] API (1): API (1) is an API through which the SMF notifies that a pre-registered UE has transitioned from a powered-off state to a powered-on state and attached to the network, and the IP address obtained at that time.

[0135] API (2): The UE is in idle mode when not communicating, and transitions to connected mode when communicating. API (2) is an API by which the AMF notifies whether the UE 40A is in idle mode or connected mode.

[0136] API (3): API (3) is an API for broadcasting a message (paging message) from the base station 30 to instruct the UE to transition from the idle mode to the connected mode.

[0137] API (4): API (4) is an API provided by the AMF for the location information of UE 40A. The AMF uses API (4) to notify UE 40A of which Tracking Area it is in, which Cell it belongs to, etc. The AMF can also use API (4) to notify UE 40A when it enters a specific area. The location information of UE 40A notified using API (4) is rough location information, unlike location information from a GPS (Global Positioning System). While location information from the TPS is treated as location information from the application layer, location information provided by the AMF is treated as location information provided by 3GPP RAN1. In this way, the AMF is provided with AIP (4) for acquiring location information from 3GPP RAN1.

[0138] <3.6. Example of API in Base Station of 5G Core Network> Generally, in a 5G network, an API of a Service Based Interface (SBI) is not output from the base station 30. However, a technique for outputting information related to a beam ID from the base station 30 is known.

[0139] In the present disclosure, the base station 30 and the wireless communication device 40 report the QoS status (an example of QoS information) to the UPF 221 of the core network CN. This QoS information and delay information are reported using, for example, an API of SBI.

[0140] <3.7. TSN> Having explained wireless networks above, we will now explain Time-Sensitive Networks (TSNs).

[0141] <3.7.1. Relationship between Industry 4.0 and TSN> Industry 4.0 is a term that refers to the fourth industrial revolution, and is a technology that realizes high-mix, low-volume production in addition to the mass production that has been practiced until now. Smart factories are one use case of Industry 4.0. Smart factories enable communication between all systems within a factory, thereby improving factory efficiency.

[0142] Digital twins are positioned as a core technology of Industry 4.0. Digital twins allow the status of systems within a factory to be understood on the network side, and this information can then be reflected in the control of actual equipment on the factory side. In recent years, digital twins have also been used in use cases such as controlling entire cities. Digital twins can be defined as a subset of Industry 4.0.

[0143] TSN is a core technology for realizing Industry 4.0. TSN is a technology that sends and receives packets on time over Ethernet (registered trademark). TSN is also used in Industry 4.0 smart factories. TSN is also used in digital twins, a core technology of Industry 4.0.

[0144] Note that IoT (Internet of Things) is used as a concept similar to Industry 4.0. In the present disclosure, IoT may be used as a concept similar to Industry 4.0 without any particular distinction.

[0145] <3.7.2. Overview of TSN Network> A TSN network is a network that places importance on the time between when a packet is sent and when it is received. To be considered time-sensitive, it is important not only that packets arrive quickly, but also that the packets arrive at the expected time. In other words, a TSN network can be defined as a network with low latency and small latency variance (jitter). TSN has been standardized in IEEE 802.1. In other words, TSN was originally a technology for wired networks.

[0146] In addition, the TSN network may be defined as a network whose purpose is to realize the functions shown in (1) to (4) below.

[0147] (1) Low latency (2) Deterministic (low jitter) (3) Reliable (low failure rate) (4) High-bandwidth (large capacity)

[0148] To achieve the above functions, TSN provides the following means.

[0149] Time synchronization Time synchronization means that time is synchronized between applications. In other words, the time of the receiving application that expects to receive a packet at a certain time is the same as the time of the sending application that wants to deliver the packet at that time. TSN uses gPTP (generalized Precision Time Protocol) to synchronize the clocks.

[0150] ・Scheduled traffic In TSN, a time slot (a location where a packet can be transmitted) is periodically provided. The communication device transmits that packet in that time slot, prioritizing it over other packets. In TSN, multiple queues are provided. When a packet to be transmitted in that time slot arrives at a queue, the prioritized packet is transmitted first. Other packets are transmitted only if there is no packet to be transmitted in that time slot. Whether a packet should be transmitted in a periodic time slot is determined by the traffic type identifier assigned to the packet (for example, the Priority Code Point in the VLAN tag in the Ethernet header). This identifier can be changed for each application. A priority control queue is provided for each network, called a bridge. Therefore, when a packet passes through multiple bridges, it is delayed at the granularity of the time slot.

[0151] Here, in TSN, applications exchange information about scheduled slots. On the other hand, in the proposed technology of the present disclosure, the UE 40 and the application client 50 installed in the application layer of the terminal device 400 cooperate to adjust the Connected Grant of the base station 30. Specifically, the UE 40 and the application client 50 cooperate to adjust the UL resource settings of the Connected Grant of the base station 30. In this way, TSN and the proposed technology of the present disclosure differ in the targets of adjustment and in the granularity of the resources that can be adjusted.

[0152] Frame Preemption is a preemption priority control mechanism that allows priority packets to wait for non-priority packets. In other words, Frame Preemption is a control rule used in multiple queues.

[0153] Per-stream filtering and policing is a method of filtering (also called shaping) each traffic stream so that it does not exceed the allowed bandwidth. For example, if traffic that is allowed at 10 Mbps becomes 20 Mbps, the communication device will buffer the traffic and then transmit it at intervals that will result in a 10 Mbps traffic rate. This will average out the traffic to 10 Mbps even if it is bursty at 20 Mbps.

[0154] Frame replication and elimination for reliability is a technology that copies a single packet into multiple copies, sends them over multiple routes, and then restores the multiple packets to a single copy once they are received. This improves reliability through redundancy in sections that use multiple routes.

[0155] These are the five main means for realizing TSN. To realize these means, TSN provides CUC (Centralized User Configuration) and CNC (Centralized Network Configuration).

[0156] The CUC is an entity that collects the requirements and settings of devices or applications that are endpoints of the TSN network and transmits them to the CNC. The CNC is an entity that issues instructions to each bridge between endpoints to realize five means.

[0157] 3.7.3 Typical Use Cases of TSN Networks A typical use case for TSN is the control of industrial equipment in a factory, which requires communication between controllers (C to C) and communication between end devices such as actuators and controllers (C to D).

[0158] The traffic required for C to C and C to D within a factory can be periodic or aperiodic (sporadic). The period also varies depending on the traffic. Some have a period of 1 ms or less, while others have a period of 10 ms to 50 ms. For example, in network control applications, the period can be as long as 50 ms to 1 s.

[0159] The present disclosure aims to improve, for example, the quality of TSN by having an information processing device (for example, the UPF 221 or the base station 30) report delay information.

[0160] <3.7.4. Functions of current 5G networks relative to TSN networks> In 3GPP Release 17, how to apply TSN to 5G networks was considered (3GPP TS23.501). In this specification, the 5G network is defined as one of the bridges defined in TSN (hereinafter also referred to as TSN bridges).

[0161] In a 5G network, the UE 40 side (device side) and the UPF 221 side (network side) can be either an entrance or an exit. When the 5G network functions as a TSN bridge, a TT (TSN translator) is placed there. The TT is a function that converts TSN settings and the like into 5G internal settings. There are two types of TTs: a DS-TT (Device-Side TSN Translator) placed on the device side and an NS-TT (Network-Side TSN Translator) placed on the network side. Note that when the UE 40 is an endpoint device of the TSN network, a DS-TT does not necessarily have to be placed.

[0162] Frame replication and elimination for reliability in TSN is achieved by sending multiple copies of a packet between DS-TT and NS-TT. In this case, it is desirable to use different carriers.

[0163] The CNC sets the 5QI (Quality of Service) QoS in the 5G network according to the requirements of TSN, such as latency. This enables the 5G network to achieve the low latency and jitter required by TSN. Current 5G networks use these low latency technologies to achieve the low jitter required by TSN.

[0164] In this way, in the current 5G system, rather than providing new functions for TSN, the 5G system realizes the functions of TSN by having the CNC on the TSN side configure what can be done with the existing 5G system.

[0165] One type of information set by the CNC in the 5G network is Time Sensitive Communication (TSC) Assistance Information. This information, which is information about traffic cycles and packet arrival times, is provided by the TSN. However, details of how the 5G system should control packets based on this information have not been considered.

[0166] As such, the 5G system is required to operate based on information provided by the TSN. However, the detailed mechanism has not yet been determined. Furthermore, when new features (technologies) are added to the TSN, the 5G system may be required to respond accordingly.

[0167] <3.8. About XR> XR is a concept that includes virtual reality (VR) and augmented reality (AR). XR is a technology that connects the real world and the virtual world.

[0168] Typically, a user enjoying an XR service wears an HMD (Head Mounted Display). The HMD (more specifically, the application client 50 mounted on the HMD, which is the terminal device 400) transmits the direction in which the user is facing via UL to an application server 10 that provides the XR service. The application server 10 can be located on, for example, a cloud.

[0169] The application server 10 creates (renders) an image that matches the direction the user is facing. The application server 10 compresses or decompresses the rendered image and transmits it to the application client 50 installed in the terminal device 400, which is an HMD, via the base station 30 and the wireless communication device 40.

[0170] This allows a user wearing an HMD to see an image in the direction they are facing.

[0171] This technology is called Cloud Rendering or Remote Rendering. With this technology, traffic sending information about the direction of the HMD via uplink triggers the provision of the service, i.e., the rendering of an image.

[0172] Therefore, it is important to reduce rendering delays that UL resources are allocated at the timing when the HMD wants to send directional information. In other words, in a communication system that provides XR services, reducing the delay in UL resource allocation improves XR performance.

[0173] 3.9. Scheduler and Resources of Base Station> Fig. 11 is a diagram showing an example of a frame configuration in 5G. Fig. 12 is a diagram showing an example of a time frame used by the base station 30.

[0174] As described above, the frame configuration of the time frame handled by the 5G base station 30 includes subframes arranged every 1 ms. Ten subframes make up one frame. The length of one frame is 10 ms.

[0175] One subframe consists of one or more slots. In 5G, one subframe includes one, two, four, eight, or sixteen slots. Figure 11 shows a case where one subframe includes two slots.

[0176] One slot includes 14 OFDM symbols. Each OFDM symbol is assigned a DL symbol (symbol indicated by "D" in FIG. 12) or a UL symbol (symbol indicated by "U" in FIG. 12). 3GPP Rel15 TS 38.213 provides multiple combinations of DL symbols and UL symbols.

[0177] Only DL packets are transmitted in symbols assigned to DL, and only UL packets are transmitted in symbols assigned to UL.

[0178] It should be noted that the flexible symbol (the symbol indicated by "F" in FIG. 12) can be used as either DL or UL.

[0179] In this way, in a 5G network, DL symbols and UL symbols are mixed within a slot, and the ratio between these is specified for each slot.

[0180] In the present disclosure, a slot containing an UL symbol allocated to a UE 40 (hereinafter also referred to as a target UE) to which the application server 10 provides a service is referred to as an UL slot. In the proposed technology of the present disclosure, it is important when the base station 30 prepares an UL slot (i.e., a slot including an UL OFDM symbol) for the target UE.

[0181] <3.10. Configured Grant Standardized in 3GPP Rel16> FIG. 13 is a sequence diagram showing an example of a procedure for transmitting UL data.

[0182] As shown in FIG. 13, in order to transmit UL data, the UE 40 transmits a Scheduling Request to the base station 30 (gNodeB in FIG. 13) (step S11).

[0183] Upon receiving the Scheduling Request, the base station 30 allocates UL resources and notifies the UE 40 of the allocation result (uplink resource allocation) using DL DCI (Down Control Information) (step S12).

[0184] Thereafter, the UE 40 transmits the UL data on a PUSCH (Phy Uplink Shared Channel) using the allocated UL resources (step S13).

[0185] As described above, up until 3GPP Rel15, in order for UE 40 to transmit UL data, it was necessary to transmit a Scheduling Request to base station 30. This method (Dynamic Grant) causes a large delay before UE 40 can transmit the UL data.

[0186] Therefore, a mechanism called Configured Grant was standardized in 3GPP Rel16.

[0187] FIG. 14 is a sequence diagram showing another example of a procedure for transmitting UL data.

[0188] In the example of FIG. 14, first, the base station 30 (gNodeB in FIG. 14) transmits a periodic uplink resource configuration to the UE 40 using RRC (step S21).

[0189] The UE 40 that has generated the UL data transmits the UL data on a PUSCH (Phy Uplink Shared Channel) using the UL resources that have already been allocated (step S22).

[0190] In this way, in the Configured Grant, the base station 30 periodically allocates UL resources in advance. At this time, the base station 30 may determine an MCS (Modulation Coding Scheme) or the like in advance. This MCS is valid for, for example, a certain period of time.

[0191] This allows the UE 40 to transmit UL data using the periodically allocated UL resources using the same MCS for a certain period of time.

[0192] However, UL resources are not necessarily allocated at the timing when UL data is generated. There is a possibility that the timing when UE 40 wants to transmit UL data and the timing when base station 30 allocates UL resources are different.

[0193] This timing discrepancy may cause a large delay in the transmission of UL data. One possible method for reducing this delay is to increase the number of UL resources allocated in advance. However, this method may result in, for example, a reduction in the number of DL resources allocated, resulting in a decrease in frequency utilization efficiency. Therefore, in the Configured Grant, UL resources are allocated periodically.

[0194] <3.11. Configured Grant under consideration in 3GPP Rel18> In 3GPP Rel18, consideration is being given to providing bursty UL resources that are periodically configured in Configured Grant. By providing bursty UL resources, even if there is a difference between the UL resources and the timing at which UE 40 wishes to send UL data, this difference can be absorbed by the bursty UL resources.

[0195] If UL resources are transmitted in bursts, the number of UL resources increases, which reduces the frequency resources available for allocating other resources. However, this is being studied as a mechanism for reducing UL delays.

[0196] <3.12. Configured Grant Required in 6G> In 6G, it is required to not only reduce the delay of UL data but also to avoid the use of unnecessary UL resources. One of the objectives of the proposed technology of the present disclosure is to enable the UE 40 to report on the delay, thereby optimizing the location of the UL resources configured by the base station 30.

[0197] <3.13. Timing Reports and Random Access> Random Access is a procedure in which UE 40 first connects to base station 30. In this procedure, a time dependent on the distance between UE 40 and base station 30 is measured. This procedure also includes a function in which UE 40 notifies base station 30 of a measurement value of the time dependent on the distance between UE 40 and base station 30. In this way, the Random Access procedure includes a partial timing report.

[0198] The timing (measured time value) reported in the Random Access is used by the base station 30 to adjust the transmission timing of the UL data so that the UL data transmitted by the UE 40 does not collide.

[0199] In this way, the timing reported in Random Access is not used to adjust the allocation of UL resources, which is different from the proposed technology of the present disclosure.

[0200] Detailed examples of embodiments of the present disclosure are described below.

[0201] <<4. Operation of the Communication System>> <4.1. Problem> If the base station 30 cannot set the UL resource of the Configured Grant to an appropriate time resource, there is a problem that the delay of the UL data increases.

[0202] Here, as described above, low latency is important in XR. In transmitting UL data in XR, securing UL resources is an adverse effect of low latency, that is, a factor that increases the latency.

[0203] For example, as shown in FIG. 13, in the case of Dynamic Grant, the UE 40 requests the base station 30 to allocate UL resources by transmitting a scheduling request to the base station 30.

[0204] In response to this, the base station 30 notifies the UE 40 of the location of the UL resource by using the DL DCI. In accordance with the notification, the UE 40 transmits UL user data (the above-mentioned UL data) using the allocated UL resource.

[0205] When the UE 40 has UL data to transmit, it needs to transmit a scheduling request to the base station 30. In this way, with Dynamic Grant, the exchange between the base station 30 and the UE 40 is one factor that increases the delay in UL transmission.

[0206] To solve this problem, a mechanism called Configured Grant was defined in 3GPP Rel16. In Configured Grant, a base station 30 periodically allocates UL resources to a UE 40 in advance (see FIG. 14). At this time, the base station 30 also determines in advance the MCS to be used for transmitting UL data, which enables the UE 40 to transmit UL data periodically.

[0207] With Configured Grant, the UE 40 can transmit UL data without exchanging data with the base station 30, and the delay of the UL data can be reduced compared to Dynamic Grant.

[0208] However, there are cases where the required low latency cannot be achieved with the Configured Grant. For example, if the timing at which UE 40 wants to transmit UL data does not match the periodic allocation of UL resources, the delay of the UL data increases. Therefore, a mechanism for adjusting this mismatch is required.

[0209] Conventionally, reports from UE 40 have only notified the channel quality and the buffer capacity of UE 40. Also, in 3GPP Rel. 17, methods such as setting UL resource transmission opportunities in bursts were also considered. Furthermore, in order to reduce UL data delays, a method for UE 40 to notify delay information related to delays caused by UL resource mismatches needs to be considered.

[0210] In this embodiment, a method for the UE 40 to know delay information related to a delay due to a deviation in L resources, for example, an appropriate timing for UL resource allocation, will be described for several use cases. Here, the following three use cases will be discussed.

[0211] Use case 1: When UL data is transmitted at a fixed timing after the arrival of DL data. Use case 2: When the terminal device 400 is the trigger to transmit UL data of traffic with periodicity or a predetermined pattern.

[0212] <4.2. First embodiment> <4.2.1. Solution> In the first embodiment, the UE 40 reports the timing of the UL resource corresponding to the DL data (an example of delay information) to the base station 30 .

[0213] Here, a method for reporting the timing of UL resources (an example of delay information) corresponding to DL data from the UE 40 to the base station 30 will be described in the following use case.

[0214] FIG. 15 is a diagram illustrating an example of a use case of the communication system according to the first embodiment of the present disclosure.

[0215] 15, an application server 10 on the network side (cloud side) is triggered to transmit DL data. The DL data arrives at an application client 50 installed in the protocol layer of the terminal device 400. The application client 50 returns a response to the DL data to the application server 10 as UL data.

[0216] The use case shown in FIG. 15 can be applied to, for example, controlling an application client 50 such as a robot from an application server 10 which is a control device.

[0217] The UL data, which is a response from the application client 50, is transmitted from the application client 50, which is the transmission source, to the UE 40. The UE 40 transmits the UL data received from the application client 50 to the base station 30 using the UL resources periodically allocated by the Configured Grant.

[0218] In this case, if UE 40 can transmit the UL data to base station 30 at the timing received from application client 50 (hereinafter also referred to as the desired timing), the delay of the UL data in UE 40 can be reduced (optimized).

[0219] However, UL resources are not necessarily allocated at the timing desired by UE 40 .

[0220] 16 is a diagram illustrating an example of a data flow according to the first embodiment of the present disclosure. In FIG. 16, a data flow within the terminal device 400 is illustrated.

[0221] First, at time t1, DL data arrives at the UE 40 from the application server 10. The UE 40 transmits this DL data to the application client 50.

[0222] At time t2, DL data arrives at the application client 50 from the UE 40. The application client 50 returns UL data in response to this DL data. For example, the application client 50 transmits UL data to the UE 40 at time t3.

[0223] The UL data transmitted from the application client 50 arrives at the UE 40 with a predetermined delay (the Application to Radio delay value in FIG. 16 ). In FIG. 16 , the UL data arrives at the UE 40 at time t4 from the application client 50. The period between time t3 and time t4 is the delay between the application client 50 and the UE 40.

[0224] Here, even if the UE 40 attempts to transmit UL data, it cannot transmit the UL data if there are no UL resources allocated by the base station 30 .

[0225] 16, UL resources are allocated at time t51, which is before time t4 when UL data arrives at UE 40, and therefore UE 40 cannot transmit UL data at this time t51. For example, in FIG. 16, time t51 is the same as time t3. That is, even if UL resources are allocated at the time when UL data is transmitted from application client 50, the UL data is not transmitted to base station 30 at this time.

[0226] Therefore, the UE 40 transmits the UL data that arrives at time t4 using the UL resources allocated at time t52, which is the next period after time t51.

[0227] Thus, depending on when the UL resources are allocated, a non-optimal delay occurs in the UL data (the delay between time t4 and time t52 in FIG. 16).

[0228] Although not shown in FIG. 16, there is a difference between the timing when UE 40 receives the UL data (time t4) and the timing when UE 40 becomes able to transmit the UL data.

[0229] Here, the timing at which UE 40 becomes able to transmit UL data means the timing at which UE 40 becomes able to transmit UL data immediately if UL resources are available.

[0230] After receiving the UL data, the UE 40 performs various processes and then transmits the UL data using the allocated UL resources. Therefore, it takes a predetermined time from when the UE 40 receives the UL data until it becomes able to transmit the UL data.

[0231] For example, the UE 40 performs various processes on the UL data and stores the data in a transmission buffer (UL buffer). The transmission buffer is a buffer for storing the UL data until a UL resource is allocated.

[0232] Therefore, hereinafter, the timing at which the UL data is stored in the transmission buffer of UE 40 is also referred to as the timing at which UE 40 becomes able to transmit the UL data, i.e., the completion timing at which preparation for transmitting the UL data is complete.

[0233] Therefore, in this embodiment, the UE 40 reports delay information regarding the completion timing to the base station 30 so that the UL resources are allocated at the completion timing when preparation for transmitting the UL data is completed.

[0234] In the following, for the sake of simplicity, unless otherwise specified, the timing at which UL data arrives at UE 40 is treated as the timing at which preparation for transmission is completed. That is, time t4 in Fig. 16 is treated as the timing at which preparation for transmission is completed.

[0235] This is because, as will be described later, the period from when UL data arrives at UE 40 until preparation for transmission is completed is considered to be approximately constant. Therefore, UE 40 can calculate the timing at which preparation for transmission is completed from the timing at which UL data arrives at UE 40. Therefore, hereinafter, unless otherwise specified, the timing at which preparation for transmission is completed will be the timing at which UL data arrives at UE 40.

[0236] The base station 30 adjusts the allocation of UL resources so that the UL resources are allocated at the completion timing.

[0237] Fig. 17 is a diagram illustrating another example of a data flow according to the first embodiment of the present disclosure. Fig. 17 illustrates a data flow within the terminal device 400. Here, the data flow is illustrated when the base station 30 adjusts the UL resources.

[0238] In FIG. 17, the adjusted UL resources are allocated at time t6 immediately after time t4 when the UL data arrives at the UE 40.

[0239] Therefore, the UE 40 can transmit the UL data to the base station 30 at time t6 after receiving the UL data from the application client 50 at time t4.

[0240] The delay when the UE 40 transmits UL data is optimized (e.g., shortest) with low latency for UL resources.

[0241] Here, it is considered that the processing speeds of the application client 50 and the UE 40 are almost constant, and therefore the time (i.e., delay) required for processing in the application client 50 and the UE 40 is also constant.

[0242] In other words, the timing from when UE 40 receives DL data from base station 30 (time t1) to when UE 40 receives UL data, which is a response to this DL data, from application client 50 and preparation for transmission is complete is considered to be constant.

[0243] Therefore, the UE 40 of this embodiment measures the delay from when it receives DL data from the base station 30 until it completes preparations to transmit UL data, which is a response to the DL data. In this case, the base station 30 corresponds to the sender of the first packet, the DL data corresponds to the first packet, and the UL data corresponds to the second packet.

[0244] It is considered that the time from when the base station 30 transmits the DL data until when the UE 40 receives the data is almost constant. This time is measured, for example, in a random access procedure.

[0245] Therefore, by measuring the delay from when UE 40 receives a DL packet to when it completes preparations to transmit UL data, UE 40 can measure the delay characteristics from when base station 30 transmits a DL packet to when it completes preparations to transmit an UL packet corresponding to the DL packet.

[0246] It is assumed that the UE 40 knows in advance the time from when it receives an UL packet to when it completes the transmission sequence. In this case, the UE 40 may measure the delay characteristic by measuring the time from when the base station 30 transmits a DL packet to when it receives an UL packet corresponding to the DL packet.

[0247] The UE 40 measures the delay between receiving the DL packet and receiving the UL data. The UE 40 notifies the base station 30 that the UL resource is allocated after the measured delay from the timing when the DL data arrives. This notification corresponds to notification of delay information based on the delay characteristics.

[0248] In this way, the UE 40 requests the base station 30 to set the UL resources so that the UL resources are allocated according to the timing of receiving the UL data. This is thought to enable the UE 40 to transmit the UL data to the base station 30 with an optimal delay.

[0249] For example, if the DL data is a moving image, this DL data can be transmitted at a predetermined period from the application server 10. In this way, when the DL data is transmitted periodically, the UE 40 calculates the reception timing of the UL data from the period for receiving the DL data, and requests the base station 30 to allocate UL resources according to this timing.

[0250] Specifically, when UE 40 measures the delay between receiving a DL packet and receiving UL data (hereinafter simply referred to as delay characteristics), the question arises as to when this measurement should be performed. For example, UE 40 measures this delay characteristic in accordance with an instruction from base station 30. In this case, the question arises as to how UE 40 receives the instruction from base station 30.

[0251] There is also a problem as to how UE 40 knows which DL data corresponds to which UL data, i.e., how UE 40 associates the DL data and UL data for which delay characteristics are measured.

[0252] Four examples of methods for solving these problems will be described below.

[0253] (First Method) As a first method, a method is conceivable in which the DL data that the UE 40 receives first after the base station 30 issues an instruction to measure the delay characteristics is identified as the DL data to be measured. In this case, the UE 40 starts measuring the delay characteristics at the timing when the DL data is first received after receiving the instruction to measure the delay characteristics from the base station 30.

[0254] Furthermore, the UE 40 identifies the UL data that is first received as the DL data to be measured after transmitting the DL data to the application client 50. In this case, the UE 40 ends the measurement of the delay characteristics at the timing when the UL data that is first received after transmitting the DL data to the application client 50 is received.

[0255] Here, if the DL data is included in the same slot as the DCI (for example, a control signal including an instruction to measure delay characteristics), the UE 40 identifies this DL data as DL data to be measured.

[0256] If no DL data is included in the same slot as the DCI (e.g., a control signal including an instruction to measure delay characteristics), i.e., if only UL data is included in this slot, UE 40 identifies the DL data included in slots after this slot as the measurement target.

[0257] The UE 40 starts measuring the delay characteristics at the timing when the specified DL data is received.

[0258] The DL data transmitted by the base station 30 may be data that is transmitted in response to a trigger, for example, from the application server 10. For example, when the base station 30 receives an instruction from the application server 10 to measure delay characteristics, the base station 30 may transmit the DL data for measurement to the UE 40.

[0259] The method by which the base station 30 identifies the DL data from the application server 10 as being for measurement may be the same as the method by which the UE 40 identifies the DL data from the base station 30 as being for measurement.

[0260] In the second to fourth methods described below, the base station 30 also uses the application server 10 as a trigger to instruct the UE 40 to measure the delay characteristics.

[0261] (Second Method) As a second method, a method can be considered in which the UE 40 starts measuring the delay characteristics at the timing when the UE 40 receives DL data having a specific DCI. In this case, the specific DCI can be considered as an instruction from the base station 30 to measure the delay characteristics.

[0262] That is, the UE 40 identifies the DL data including the instruction to measure the delay characteristics as a target for measuring the delay characteristics. Note that the UE 40 can end the measurement of the delay characteristics in the same manner as in the first method.

[0263] (Third Method) For example, a method is considered in which the base station 30 stops other traffic and transmits DL data to be measured. In this case, the UE 40 identifies the DL data received while the other traffic is stopped as the measurement target. Also, the UE 40 identifies the UL data received while the other traffic is stopped as the measurement target.

[0264] The base station 30 may stop other traffic in order to measure delay characteristics in response to a request from the UE 40, or may stop other traffic in accordance with a predetermined trigger such as a predetermined period.

[0265] Furthermore, the base station 30 may notify the UE 40 that other traffic has been stopped, in other words, instruct the UE 40 to measure delay characteristics.

[0266] (Fourth Method) As a fourth method, a measurement target may be identified using a QoS identifier assigned to each traffic. For example, a measurement QoS identifier is assigned to DL data and UL data whose delay characteristics are to be measured.

[0267] The UE 40 measures the delay characteristics by associating the DL data and UL data to which the measurement QoS identifier is assigned.

[0268] UE 40 starts measuring delay characteristics when it receives DL data belonging to a session corresponding to the QoS identifier for measurement, and ends measuring delay characteristics when it receives UL data belonging to a session corresponding to the QoS identifier for measurement from application client 50.

[0269] In this way, the UE 40 identifies the DL data and UL data for measurement using a QoS identifier associated with a bearer (also referred to as, for example, a communication session, a communication channel, or traffic). Note that in 5G, the QoS identifier is called a 5QI.

[0270] In a use case in which the delay time of UL data corresponding to DL data is measured (i.e., the use case of this embodiment), the communication system assigns a QoS identifier (5QI) to a specific bearer indicating this use case.

[0271] FIG. 18 is a diagram illustrating an example of a use case of the communication system according to the first embodiment of the present disclosure.

[0272] 18, the application server 10 is triggered to transmit DL data to which a measurement QoS identifier (5QI) is assigned. The DL data arrives at the application client 50 installed in the protocol layer of the terminal device 400. The application client 50 returns a response to the DL data to the application server 10 as UL data to which a measurement QoS identifier (5QI) is assigned.

[0273] The UE 40 starts measuring the delay characteristics when it receives DL data to which a measurement QoS identifier (5QI) is assigned and which is transmitted by the application server 10. The UE 40 ends measuring the delay characteristics when it receives UL data to which a measurement QoS identifier (5QI) is assigned from the application client 50. That is, the UE 40 measures the delay characteristics of the UL data to which the same QoS identifier (5QI) as the DL data is assigned.

[0274] The UE 40 notifies the base station 30 of information (an example of delay information) relating to the location of the desired UL resource in accordance with the measured delay characteristics.

[0275] For example, the UE 40 notifies the base station 30 of information indicating how far forward or backward the currently set UL resource position should be shifted. In this case, the base station 30 adjusts the UL resource position in accordance with the notification from the UE 40.

[0276] Alternatively, the UE 40 may notify the base station 30 of the measured delay characteristics as delay information. The base station 30 adjusts the position of the UL resource based on the timing of transmitting the DL data for measurement and the delay characteristics notified from the UE 40 (more specifically, the delay time from receiving the DL data to receiving the UL data).

[0277] For example, the base station 30 calculates the timing at which the UE 40 receives the UL data from the timing at which the DL data for measurement is transmitted and the delay characteristics notified from the UE 40, and sets the UL resource at the calculated timing.

[0278] Fig. 19 is a diagram illustrating another example of a data flow according to the first embodiment of the present disclosure. Fig. 19 illustrates a data flow within the terminal device 400. Here, the data flow is illustrated when the base station 30 adjusts the UL resources.

[0279] UE 40 measures the delay characteristic (referred to as UE side loopback delay value in FIG. 19) from time t1 (the timing of receiving DL data to which a measurement QoS identifier (5QI) is assigned) shown in FIG. 19 to time t4 (the timing of receiving UL data to which a measurement QoS identifier (5QI) is assigned).

[0280] The base station 30 adjusts the allocation of UL resources based on the measurement results of the delay characteristics. Therefore, in Fig. 19, the adjusted UL resources are allocated at time t6, which is immediately after time t4 when the UL data arrives at the UE 40.

[0281] Therefore, the UE 40 can transmit the UL data to the base station 30 at time t6 after receiving the UL data from the application client 50 at time t4.

[0282] The delay when the UE 40 transmits UL data is optimized (e.g., shortest) with less latency for UL resources.

[0283] In this way, the UE 40 measures the delay characteristics (UE side loopback delay value) and reports it to the base station 30, which enables the base station 30 to adjust the UL resource configuration, thereby enabling the UE 40 to further reduce the delay of UL data.

[0284] The UE 40 transmits UL data for measurement and transmits a report of delay information based on the delay characteristics. The UL data is transmitted, for example, using UL resources set by the Configured Grant. The report of the delay information is transmitted, for example, using a UL control channel separate from the UL resources. More specifically, the report of the delay information based on the delay characteristics can be transmitted using a PUCCH (Physical Uplink Control Channel).

[0285] The UE 40 can transmit the report of the delay information at a predetermined cycle or timing. The report of the delay information may be transmitted periodically in this manner or aperiodic.

[0286] In this method, a specific (i.e., measurement-specific) QoS identifier is newly created for measuring delay characteristics. For the bearer to which this QoS identifier is assigned, delay characteristics are measured by the UE 40. Delay information based on the measured delay characteristics is reported to the base station 30, and is used by the base station 30 to adjust UL resources.

[0287] For example, the base station 30 allocates UL resources at a timing when a delay characteristic (UE side loopback delay value) has elapsed since the time when the DL data was transmitted.

[0288] More specifically, the base station 30 determines the timing for periodically transmitting DL data, and then periodically allocates the UL resources of the Configured Grant at an appropriate location from the determined timing (for example, at a timing when a delay characteristic (UE side loopback delay value) has elapsed from the determined timing).

[0289] When there is no DL data to be transmitted to the UE 40, there is also no UL data in response to this DL data, and therefore the base station 30 can refrain from allocating UL resources.

[0290] That is, when UL data having a corresponding QoS identifier is received, the UE 40 can recognize that UL resources for transmitting the UL data are prepared.

[0291] For example, the base station 30 may adjust the timing of the UL resources on a slot-by-slot basis based on reports from the UE 40 .

[0292] In this embodiment (means for UE 40 to measure delay characteristics), UE 40 needs to have a function for measuring delay characteristics. In other words, UE 40 needs to have the capability to measure delay characteristics.

[0293] Therefore, the UE 40 may include information indicating that it is capable of measuring delay characteristics in the UE capability that it transmits to the base station 30. If the UE 40 has the capability to measure delay characteristics, the base station 30 instructs the UE 40 to measure the delay characteristics. For example, in the fourth method, if the UE 40 has the capability to measure delay characteristics, the communication system uses a bearer with a QoS identifier for measurement.

[0294] (Communication Processing Example) Fig. 20 is a sequence diagram illustrating an example of the flow of communication processing according to the first embodiment of the present disclosure. The communication processing illustrated in Fig. 20 is executed in a communication system when adjusting UL resources. The communication processing is executed, for example, at a predetermined cycle or in response to a predetermined trigger (for example, an instruction from the base station 30 or the application server 10).

[0295] First, the base station 30 (gNodeB in FIG. 20) configures periodic uplink resources using a Configured Grant (step S101). This configuration is the configuration before adjusting the UL resources.

[0296] Next, a data signal is transmitted from the application server 10 to the base station 30 (step S102), which then transmits the data signal to the UE 40 (step S103) and then to the application client 50 (step S104).

[0297] The application client 50 transmits a control signal to the UE 40 in response to the data signal (step S105). Note that the control signal transmitted here is a control signal in the application of the communication system, and is different from a control signal exchanged in a 5G system, for example, between the UE 40 and the base station 30.

[0298] Here, the UE 40 measures the time from when it receives the data signal until when it receives the control signal, that is, the time between step S104 and step S105, as the delay characteristic (the UE side loopback delay value).

[0299] The UE 40 transmits a control signal to the base station 30 at the periodic timing of the UL resource (step S106). At this time, the UL resource is not adjusted, so a large, unoptimized delay occurs between when the UE 40 receives the control signal and when it transmits it to the base station 30.

[0300] The base station 30 transmits a control signal to the application server 10 (step S107).

[0301] The UE 40 reports the measured delay characteristic (the UE side loopback delay value) to the base station 30 (step S108). The UE 40 reports using, for example, the PUCCH.

[0302] The base station 30 configures periodic uplink resources using the Configured Grant based on the reported delay characteristics (the UE side loopback delay value) (step S109). This configuration is the configuration after the UL resource adjustment.

[0303] Next, a data signal is transmitted from the application server 10 to the base station 30 (step S110). This data signal is transmitted from the base station 30 to the UE 40 (step S111) and then to the application client 50 (step S112).

[0304] The application client 50 transmits a control signal to the UE 40 in response to the data signal (step S113).

[0305] The UE 40 transmits a control signal to the base station 30 at the periodic timing of the UL resource (step S114). At this time, since the UL resource is adjusted, the delay that occurs from when the UE 40 receives the control signal to when it transmits the control signal to the base station 30 is optimized, for example, the shortest delay.

[0306] The base station 30 transmits a control signal to the application server 10 (step S115).

[0307] In the above-described step S108, the UE 40 reports the delay characteristics using the PUCCH, but the UE 40 may report using a channel other than the PUCCH. For example, an API for SBI may be provided in the base station 30, and the UE 40 may report the delay characteristics via this API.

[0308] The SBI is provided in the core network CN, but in this proposed technology that combines applications and wireless access technology, we believe that a method in which UE 40 reports using an API that can also be accessed from the application side will become important in the future.

[0309] The aforementioned TSN is known as a technique for adjusting transmission timing. This technique for adjusting the timing of UL resources differs from the TSN, which adjusts transmission timing between applications, in that the UE 40 measures delay characteristics and reports the results to the base station 30.

[0310] In the proposed technology, the UE 40 measures the delay time (delay characteristics) from when the UE 40 receives DL data until the application client 50 processes the data and then sends back UL data as a response. The UE 40 reports the measured delay time to the base station 30, allowing the base station 30 to allocate appropriate UL resources.

[0311] In this respect, the proposed technology differs from technologies that report whether to advance or delay UL resources on a slot-by-slot basis, and technologies that report information to the base station 30 regarding the time required to set UL resources at appropriate locations on a slot-by-slot basis.

[0312] <4.2.2. Effects> In this embodiment, the base station 30 can know delay characteristics, including delays that depend on the capabilities of the application client 50 installed in the terminal device 400. This allows the base station 30 to set UL resources at a more appropriate time, thereby suppressing increases in delay. In particular, this embodiment is effective for applications that require an instantaneous response, in other words, as fast as possible, to a query (DL data) from the application server 10. An example of such an application is remote control, such as piloting a drone.

[0313] <4.3. Second embodiment> <4.3.1. Solution> In the second embodiment, when the terminal device 400 is triggered to transmit UL data, the UE 40 reports the delay characteristics.

[0314] Here, a method for reporting the timing of UL resources (an example of delay information) corresponding to UL data from the UE 40 to the base station 30 will be described in the following use case.

[0315] FIG. 21 is a diagram illustrating an example of a use case of the communication system according to the second embodiment of the present disclosure.

[0316] 21 , an application client 50 installed in the protocol layer of the terminal device 400 is triggered to transmit UL data. The UL data arrives at an application server 10 on the network side (cloud side). The application server 10 returns a response to the UL data to the application client 50 as DL data.

[0317] The use case shown in FIG. 15 is a case in which, for example, even when there is no DL data at all, the terminal device 400 is triggered to transmit UL data periodically or according to a specific pattern.

[0318] For example, when an application provides an XR service, a case in which the application client 50 transmits the position of the terminal device 400, which is an HMD, to the application server 10 corresponds to this use case.

[0319] In such a use case, the timing at which the application client 50 transmits UL data often does not match the timing of the UL resources allocated for transmitting the UL data.

[0320] This is because a certain amount of time occurs between when the application client 50 transmits the UL data and when the data arrives at the wireless communication unit 41 (an example of a communication unit) of the UE 40. This time is typically, for example, several μs to several ms.

[0321] As described above, even if UE 40 is ready to transmit UL data, the timing at which UL resources are available may differ from the timing at which the UE is ready to transmit. In this case, UE 40 waits until the timing of the next UL resource before transmitting the UL data. This increases the delay of the UL data.

[0322] 22 is a diagram illustrating an example of a data flow according to the second embodiment of the present disclosure. In FIG. 22, a data flow within the terminal device 400 is illustrated.

[0323] First, at time t11, the application client 50 transmits UL data to the UE 40. This UL data arrives at the UE 40 from the application client 50 at time t12.

[0324] The delay time from when the UL data is transmitted from the application client 50 until it arrives at the UE 40, that is, the period from time t11 to time t12, is the delay characteristic (Application to Radio delay value) of this embodiment.

[0325] Here, even if the UE 40 attempts to transmit UL data, it cannot transmit the UL data if there are no UL resources allocated by the base station 30 .

[0326] For example, in Fig. 22, UL resources are allocated at time t13, which is before time t12 when UL data arrives at UE 40, so UE 40 cannot transmit the UL data at this time t13. For example, in Fig. 22, time t13 is the same as time t11. That is, even if UL resources are allocated at the time when UL data is transmitted from application client 50, the UL data is not transmitted to base station 30 at this time. Therefore, UE 40 transmits the UL data that arrives at time t12 using UL resources allocated at time t14, which is the next period after time t13.

[0327] In this way, depending on the timing at which UL resources are allocated, unnecessary delays occur in UL data (delays between time t12 and time t14 in FIG. 22).

[0328] Therefore, in this embodiment, the UE 40 reports delay information regarding the reception timing to the base station 30 so that the UL resource is allocated at the reception timing of the UL data.

[0329] The base station 30 adjusts the allocation of UL resources so that the UL resources are allocated at the reception timing.

[0330] Fig. 23 is a diagram illustrating another example of a data flow according to the second embodiment of the present disclosure. Fig. 23 illustrates a data flow within the terminal device 400. Here, the data flow is illustrated when the base station 30 adjusts the UL resources.

[0331] In FIG. 23, the adjusted UL resources are allocated at time t15 immediately after time t12 when the UL data arrives at the UE 40.

[0332] Therefore, the UE 40 can transmit the UL data to the base station 30 at time t15 after receiving the UL data from the application client 50 at time t12.

[0333] The delay when the UE 40 transmits UL data is optimized (e.g., shortest) with low latency for UL resources.

[0334] The delay information reported by the UE 40 to the base station 30 is, for example, the time obtained by adding the delay to the transmission time of the application client 50. For example, the UE 40 reports to the base station 30, as delay information, time t12 obtained by adding the measured delay characteristic (Application to Radio delay value) to time t11 in Fig. 17 .

[0335] Specifically, the UE 40 measures the delay characteristic (Application to Radio delay value) in advance, and acquires the transmission pattern of the UL data of the application client 50.

[0336] The UE 40 calculates the UL transmission timing for the wireless link, taking into account the delay characteristics of the acquired transmission pattern, in other words, the timing at which the UL data is stored in a transmission buffer (UL buffer) of the UE 40. The UE 40 reports the calculated transmission timing to the base station 30.

[0337] As a method for measuring the delay characteristics, there is a method in which the application client 50 assigns a transmission time to the UL data. In this case, it is assumed that the time between the application client 50 and the UE 40 is synchronized.

[0338] The UE 40 measures the delay characteristics from the difference between the time when the UL data is received and the transmission time assigned to this UL data.

[0339] The application client 50, for example, predicts a transmission pattern of UL data and notifies the UE 40. The application client 50 typically notifies the UE 40 of the transmission pattern using periodic (cycle) and absolute time. For example, the application client 50 notifies the UE 40 of the absolute time at which the UL data will be first transmitted and the period at which the UL data will be transmitted thereafter.

[0340] The UE 40 ascertains the location of the UL resource within the radio frame from the transmission pattern acquired from the application client 50 and the measured delay characteristics. That is, the UE 40 determines, from the transmission pattern and delay characteristics, to which location in the radio frame the UL resource should be allocated in order to minimize the delay of the UL data.

[0341] The UE 40 calculates the difference (deviation) between the location of the UL resource that it has grasped and the allocation of the UL resource set by the base station 30. In this way, the UE 40 determines how far forward or how far backward the current location of the UL resource should be shifted to minimize the delay.

[0342] For example, if the delay will be minimized if the current UL resource position is allocated five slots earlier, UE 40 reports delay information (e.g., "-5") to base station 30 to have the entire UL resource allocated five slots earlier.

[0343] For example, if the delay will be minimized if the current UL resource position is allocated three slots later, UE 40 reports delay information (e.g., "+3") to base station 30 to have the entire UL resource allocated three slots later.

[0344] Note that delay information that requests adjustment of UL resources by specifying an amount of shift of the UL resources, such as "-5" or "+3," can also be applied to embodiment 1. The amount of shift of the UL resources (adjustment amount) specified by UE 40 is an example of delay information related to allocation of UL resources used to transmit UL data after receiving the UL data.

[0345] Furthermore, the UE 40 may report the transmission pattern acquired from the application client 50 and the measured delay characteristics as delay information to the base station 30. In this case, the base station 30 determines, based on the delay information, how far forward or how far backward the current UL resource position should be shifted to minimize the delay, and adjusts the allocation of the UL resources.

[0346] (Communication Processing Example) Fig. 24 is a sequence diagram illustrating an example of the flow of communication processing according to the second embodiment of the present disclosure. The communication processing illustrated in Fig. 24 is executed in a communication system when adjusting UL resources. The communication processing is executed, for example, at a predetermined cycle or in response to a predetermined trigger (for example, an instruction from the base station 30 or the application server 10).

[0347] The application client 50 transmits a time-stamped measurement packet (DL data) to the UE 401 (step S201). The UE 40 measures the delay characteristic (Application to Radio delay value) of this measurement packet.

[0348] The application client 50 requests application-level UL resource timing (step S202). This corresponds to the notification of the transmission pattern described above. That is, the application client 50 notifies the UE of the transmission timing (transmission pattern) of UL data at the application level as the UL resource timing, thereby requesting the UE 40 to reserve UL resources at the timing.

[0349] Here, the UL resource timing requested by the application client 50 is at the application level, that is, the timing at which the application client 50 transmits DL data.

[0350] As described above, the timing at which the application client 50 transmits UL data differs from the timing at which the UE 40 becomes ready to transmit this UL data (the timing at which preparation for transmission is completed).

[0351] Therefore, UE 40 converts the UL resource timing at the application level into UL resource timing at the radio frame level (step S203). Based on the measured delay characteristics, UE 40 calculates the UL resource timing at the radio frame level by shifting the UL resource timing at the application level.

[0352] The UE 40 reports a request for UL resource timing at the radio frame level to the base station 30 (gNodeB in FIG. 24) (step S204).

[0353] The base station 30 configures (Configuration) periodic uplink resources using the Configured Grant based on the UL resource timing at the radio frame level (step S205). This configuration is the configuration after the UL resource adjustment.

[0354] Next, the application client 50 transmits a control signal to the UE 40 (step S206). Note that the control signal transmitted here is a control signal in the application of the communication system, and is different from a control signal exchanged in a 5G system, for example, between the UE 40 and the base station 30.

[0355] The UE 40 transmits the control signal to the base station 30 at the periodic timing of the UL resource (step S207). At this time, since the UL resource is adjusted, the delay that occurs from when the UE 40 receives the control signal to when it transmits the control signal to the base station 30 is optimized, for example, the shortest delay.

[0356] The base station 30 transmits a control signal to the application server 10 (step S208).

[0357] The aforementioned TSN is known as a technique for adjusting transmission timing, in which transmission timing is adjusted between TSN-compatible applications.

[0358] On the other hand, the present technology adjusts the timing of allocation of slots of UL resources in the Configured Grant based on the transmission timing of UL data from the application client 50. In this respect, the present technology differs from TSN.

[0359] <4.3.2. Effects> In this embodiment, the base station 30 can know delay characteristics including delays that depend on the capabilities of the application client 50 installed in the terminal device 400. This allows the base station 30 to set UL resources at more appropriate times, thereby suppressing increases in delay.

[0360] In particular, the communication system according to this embodiment can reduce delays when transmitting the orientation of the HMD to a cloud-side rendering device (an example of the application server 10) in XR, etc. In this way, the communication system according to this embodiment is suitable for a system in which the application client 50 periodically transmits UL data to the application server 10.

[0361] <4.4. Third Embodiment> <4.4.1. Solution> In the third embodiment described above, the UE 40 reports delay information (for example, UL resource timing at the radio frame level) according to the delay characteristics to the base station 30. However, the UE 40 may report the delay information to the application client 50.

[0362] In this case, delay information is exchanged within the terminal device 400. Therefore, the technology according to this embodiment can be realized by implementing it in the terminal device 400.

[0363] As described above, a certain amount of time occurs between when the application client 50 transmits the UL data and when the data arrives at the wireless communication unit 41 (an example of a communication unit) of the UE 40. Therefore, a delay occurs because the timing at which the application client 50 transmits the UL data does not match the timing of the UL resources allocated for transmitting the UL data.

[0364] In the second embodiment, the delay is reduced by adjusting the timing of the UL resources set by the base station 30.

[0365] In this embodiment, the UE 40 reports delay information based on the timing of the UL resources set by the base station 30 to the application client 50. Furthermore, the application client 50 adjusts the transmission timing of the UL data at the application level based on the delay information, thereby reducing the delay.

[0366] Fig. 25 is a diagram illustrating an example of a data flow according to the third embodiment of the present disclosure. Fig. 25 illustrates a data flow within the terminal device 400. Here, the data flow is illustrated when the application client 50 adjusts the transmission timing of the UL data.

[0367] 22, the UL data is transmitted from the application client 50 at time t11 and arrives at the UE 40 at time t12. Therefore, the UE 40 cannot transmit the UL data at time t13, which is earlier than time t12.

[0368] 25, the application client 50 transmits UL data at time t21, which arrives at the UE 40 at time t22.

[0369] Therefore, the UE 40 can transmit the UL data to the base station 30 at time t14 after receiving the UL data from the application client 50 at time t22.

[0370] The delay when the UE 40 transmits UL data is optimized (e.g., shortest) with low latency for UL resources.

[0371] For example, the UE 40 measures the time it takes for UL data to arrive at the UE 40 from the application client 50 (Application to Radio delay value, an example of delay characteristics).

[0372] The UE 40 obtains the timing of the UL resources set by the base station 30 and converts this timing to, for example, absolute time, which is a time that is synchronized between the UE 40 and the application client 50.

[0373] The UE 40 calculates the transmission timing of the UL data at the application client 50 that will shorten the delay, based on the timing and delay characteristics of the UL resource converted into absolute time. The UE 40 reports the calculated transmission timing to the application client 50.

[0374] The UE 40 sets the transmission timing of the UL data at the application client 50 to, for example, an absolute time obtained by going back by the delay characteristic from the timing of the UL resource converted into absolute time.

[0375] The application client 50 transmits the UL data at the transmission timing reported from the UE 40. This allows the application client 50 to further reduce the delay of the UL data.

[0376] The delay characteristics (Application to Radio delay value) can be measured in the same manner as in the second embodiment.

[0377] Furthermore, the UE 40 converts the timing of the UL resource on the radio frame into absolute time by, for example, expressing the period of the radio frame in absolute time and calculating the absolute time of the slot of the radio frame.

[0378] The UE 40 may periodically report the transmission timing of the UL data (an example of delay information) calculated based on the delay characteristics to the application client 50, or may report the timing when there is a change in the transmission timing. The transmission timing of the UL data calculated based on the delay characteristics changes, for example, when the setting of the Configured Grant is changed.

[0379] (Communication Processing Example) Fig. 26 is a sequence diagram illustrating an example of the flow of communication processing according to the third embodiment of the present disclosure. The communication processing illustrated in Fig. 26 is executed in a communication system when adjusting the transmission timing of UL data. The communication processing is executed, for example, at a predetermined cycle or in response to a predetermined trigger (for example, when the setting of the Configured Grant is changed).

[0380] The same processes as those in FIG. 24 are denoted by the same reference numerals and the description thereof will be omitted.

[0381] The base station 30 (gNodeB in the example of FIG. 26) configures periodic uplink resources using the Configured Grant (step S301). This configuration does not include any particular adjustment of UL resources.

[0382] The UE 40 monitors the periodic uplink resources, and converts the UL resource timing at the radio frame level into the UL resource timing at the application level (step S302).

[0383] For example, the UE 40 converts the timing of the UL resource into absolute time, and calculates the transmission timing of the UL data at the application level based on the delay characteristic (Application to Radio delay value). The UE 40 sets the transmission timing of the UL data at the application level as the UL resource timing at the application level.

[0384] The UE 40 reports the application level UL resource timing to the application client 50 (step S303).

[0385] Based on the report, the application client 50 transmits UL data, which is a control signal, at an optimized timing (step S304).

[0386] The UE 40 transmits a control signal to the base station 30 at the timing of the periodic UL resource (step S305). At this time, since the transmission timing of the control signal is adjusted, the delay that occurs from when the UE 40 receives the control signal to when it transmits the control signal to the base station 30 is optimized, for example, the shortest delay.

[0387] As mentioned above, the TSN is known as a technique for adjusting transmission timing, and in TSN, transmission timing is adjusted between TSN-compatible applications.

[0388] On the other hand, the present technology adjusts the transmission timing of UL data from the application client 50 based on the timing of the allocation of UL resource slots in the Configured Grant. For this reason, the UE 40 reports the timing of the UL resource in the Configured Grant to the application client 50. In this respect, the present technology differs from TSN.

[0389] <4.4.2. Effects> In this embodiment, the base station 30 can know delay characteristics including delays that depend on the capabilities of the application client 50 installed in the terminal device 400. This allows the base station 30 to set UL resources at more appropriate times, thereby suppressing increases in delay.

[0390] In particular, the communication system according to this embodiment can reduce delays when transmitting the orientation of the HMD to a cloud-side rendering device (an example of the application server 10) in XR, etc. In this way, the communication system according to this embodiment is suitable for a system in which the application client 50 periodically transmits UL data to the application server 10.

[0391] Furthermore, in this embodiment, since the UE 40 reports delay information to the application client 50, the present technology can be realized by implementing it in the UE 40 without changing the 3GPP (registered trademark) standard.

[0392] <4.5. Fourth embodiment> <4.5.1. Solution> 3GPP Rel18 is considering adding burstiness to periodic UL resources, which will reduce delays caused by suboptimal adjustment of the transmission timing of UL data and the timing of UL resources.

[0393] Fig. 27 is a diagram showing an example of allocation of bursty UL resources. As shown in Fig. 27, when periodic UL resources are made bursty, UL resources that are allocated consecutively over multiple slots are allocated periodically.

[0394] In this way, by allocating UL resources in bursts, if the transmission timing of the application client 50 is within the range of the UL resource burst, the UE 40 can transmit UL data without delay.

[0395] The burst is set by the base station 30. If the base station 30 knows the degree of fluctuation in the UL data transmission by the application client 50, the base station 30 can set the burst of the UL resource more effectively. This is because the base station 30 can determine the position and width of the burst based on the range of fluctuation by understanding the transmission fluctuation of the UL data.

[0396] The burst position can be determined by the base station 30 based on a report from the UE 40, for example, using the techniques described in the above-mentioned first and second embodiments. Alternatively, the application client 50 may transmit UL data in accordance with the burst position set by the base station 30, using the technique described in the third embodiment.

[0397] Furthermore, the UE 40 may report to the base station 30 the degree of fluctuation in the transmission of UL data by the application client 50. This makes it easier for the base station 30 to set bursts of UL resources. That is, the base station 30 can set bursts of UL resources with a smaller width and at positions where UL data can be transmitted more reliably.

[0398] One method for the UE 40 to grasp the range of fluctuation in transmission of UL data by the application client 50, i.e., the range of a burst, is for the UE 40 to measure the UL data. In this case, the UE 40 is provided with a function for measuring the burst of UL data arriving from the application client 50.

[0399] The burst of UL data arriving from the application client 50 is measured by measuring the arrival time of the UL data multiple times.

[0400] For example, when UE 40 receives UL data multiple times (e.g., 100 times), it statistically processes the arrival of bursty UL data. For example, when UE 40 receives UL data multiple times (e.g., 100 times), it statistically processes the reception timing (e.g., the reception interval of UL data).

[0401] The UE 40 determines the range of bursts that includes, for example, 99.99% of the UL data reception timing, and notifies the base station 30 of the determined range value.

[0402] The UE 40 can generate UL data in the same manner as in the first and second embodiments. For example, the UE 40 requests the base station 30 (or the application server 10) or the application client 50 to transmit DL data multiple times. Alternatively, the UE 40 may measure the timing of receiving DL data multiple times in accordance with an instruction from the base station 30 (or the application server 10) or the application client 50.

[0403] (Communication Processing Example) Fig. 28 is a sequence diagram showing an example of the flow of communication processing according to the third embodiment of the present disclosure. The communication processing shown in Fig. 28 is executed in a communication system when adjusting a burst of UL resources. The communication processing is executed, for example, at a predetermined cycle or in response to a predetermined trigger (for example, an instruction from the base station 30 or the application server 10).

[0404] The same processes as those in FIG. 20 are denoted by the same reference numerals, and the description thereof will be omitted.

[0405] As shown in Fig. 28 , a data signal is transmitted, for example, 100 times from base station 30 (gNodeB in Fig. 28 ) (step S401). UE 40 measures the delay characteristic (UE side loopback delay value) from a control signal that is a response to this data signal in order to know the delay distribution (burst).

[0406] Based on this measurement, the UE 40 reports the distribution (burst) of the delay characteristics (UE side loopback delay value) to the base station 30 (step S402).

[0407] Based on the report of the delay characteristics, the base station 30 configures periodic uplink resources using the Configured Grant (step S403). At this time, the base station 30 configures the UL resources so that they have burstiness.

[0408] 4.5.2 Effects In this embodiment, the base station 30 sets bursty UL resources, which can reduce the transmission delay of UL data even when the transmission cycle of DL data or UL data fluctuates.

[0409] Furthermore, by the UE 40 notifying the base station 30 of information related to the transmission fluctuation of the UL data (for example, the range of the burst), the base station 30 can allocate the UL resource to a more appropriate position, in other words, while reducing the burst width. This allows the base station 30 to set the UL resource so as to reduce the delay of the UL data while reducing the impact on other traffic (for example, transmission of DL data, etc.).

[0410] <<5. Other Embodiments>> The above-described embodiment is merely an example, and various modifications and applications are possible. The processing according to each of the above-described embodiments may be implemented in various different forms (modifications) other than the above-described embodiments. For example, the system configuration is not limited to the above-described examples, and may be in various forms.

[0411] The application server 10, the information processing device 20, or the control device that controls the base station 30 in this embodiment may be realized by a dedicated computer system or a general-purpose computer system.

[0412] For example, a communication program for executing the above-described operations is stored in a computer-readable recording medium such as an optical disk, a semiconductor memory, a magnetic tape, or a flexible disk and distributed. Then, for example, the program is installed on a computer and the above-described processing is executed to configure a control device. In this case, the control device may be a device (e.g., a personal computer) external to the application server 10, the information processing device 20, or the base station 30. Alternatively, the control device may be a device (e.g., a control unit 13, a control unit 23, or a control unit 33) internal to the application server 10, the information processing device 20, or the base station 30.

[0413] The communication program may also be stored in a disk device provided in a server device on a network such as the Internet, and may be downloaded to a computer. The above-mentioned functions may also be realized by cooperation between an operating system (OS) and application software. In this case, the components other than the OS may be stored on a medium and distributed, or may be stored in a server device and downloaded to a computer.

[0414] Furthermore, among the processes described in the above embodiments, all or part of the processes described as being performed automatically can be performed manually, or all or part of the processes described as being performed manually can be performed automatically using a known method. In addition, the information including the processing procedures, specific names, various data, and parameters shown in the above documents and drawings can be changed as desired unless otherwise specified. For example, the various information shown in each drawing is not limited to the information shown in the drawings.

[0415] Furthermore, the components of each device shown in the figure are conceptual functional units and do not necessarily have to be physically configured as shown. In other words, the specific form of distribution and integration of each device is not limited to that shown in the figure, and all or part of the devices can be functionally or physically distributed and integrated in any unit depending on various loads, usage conditions, etc. Note that this distribution and integration configuration may also be performed dynamically.

[0416] The above-described embodiments can be combined as appropriate within the scope of the processing content without causing inconsistency. The order of the steps shown in the sequence diagrams of the above-described embodiments can be changed as appropriate.

[0417] Furthermore, for example, the present embodiment can also be implemented as any configuration that constitutes an apparatus or system, such as a processor as a system LSI (Large Scale Integration), a module using multiple processors, a unit using multiple modules, a set in which other functions are added to a unit, or the like (i.e., a configuration of a part of an apparatus).

[0418] In this embodiment, a system refers to a collection of multiple components (devices, modules (components), etc.), regardless of whether all of the components are in the same housing. Therefore, multiple devices housed in separate housings and connected via a network, and a single device in which multiple modules are housed in a single housing, are both systems.

[0419] Furthermore, for example, this embodiment can have a cloud computing configuration in which one function is shared and processed jointly by a plurality of devices via a network.

[0420] <<6. Conclusion>> Although the embodiments of the present disclosure have been described above, the technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present disclosure. Furthermore, components of different embodiments and modifications may be combined as appropriate.

[0421] Furthermore, the effects of each embodiment described in this specification are merely examples and are not intended to be limiting, and other effects may also be obtained.

[0422] The present technology may also be configured as follows. (1) A communication device mounted on a terminal device, comprising: a communication unit that receives a first packet from a sender of the first packet and transmits the first packet to a destination; and a control unit that measures a delay characteristic from when the sender of the first packet transmits the first packet until the communication unit completes preparations for transmission of a second packet corresponding to the first packet, and notifies at least one of a base station and an application mounted on the terminal device of delay information based on the delay characteristic. (2) The communication device described in (1), in which the control unit measures the delay characteristic when the first packet is downlink data transmitted by the base station and the second packet is uplink data corresponding to the downlink data. (3) The communication device described in (1) or (2), in which the control unit measures the delay characteristic from when downlink data is received from the base station until preparations for transmission of uplink data corresponding to the downlink data are completed. (4) The communication device described in any one of (1) to (3), in which the control unit measures the delay characteristic based on an instruction from the base station. (5) The communication device according to any one of (1) to (4), wherein, after receiving an instruction from the base station to measure the delay characteristics, the control unit measures the delay characteristics using downlink data transmitted from the base station and uplink data corresponding to the downlink data. (6) The communication device according to any one of (1) to (4), wherein the control unit measures the delay characteristics using downlink data having a predetermined DCI and uplink data corresponding to the downlink data. (7) The communication device according to any one of (1) to (4), wherein the control unit measures the delay characteristics using downlink data having a predetermined QoS identifier and uplink data corresponding to the downlink data. (8) The communication device according to (7), wherein the control unit measures the delay characteristics using the uplink data having a QoS identifier that is the same as the predetermined QoS identifier included in the downlink data.(9) The communication device according to (7) or (8), wherein the predetermined QoS identifier is a QoS identifier for measuring the delay characteristics. (10) The communication device according to any one of (1) to (9), wherein the control unit transmits uplink data corresponding to the downlink data using uplink resources set by the base station according to the transmission period of the downlink data and the delay information. (11) The communication device according to (1), wherein the control unit measures, as the delay characteristics, a delay time from when the application transmits the uplink data to when the communication unit completes preparations to transmit the uplink data. (12) The communication device according to (11), wherein the control unit measures the delay characteristics according to the time when the application transmits the uplink data and the time when the communication unit completes preparations to transmit the uplink data. (13) The communication device according to (11) or (12), wherein the delay information includes an adjustment amount of uplink resources. (14) The communication device according to any one of (1) to (13), wherein the control unit notifies the base station of delay information regarding allocation of resources to be used for transmitting the second packet after preparation for transmission of the second packet is completed in accordance with the delay characteristics. (15) The communication device according to any one of (1) to (14), wherein uplink resources allocated for transmitting the second packet have burstiness after preparation for transmission of the second packet is completed. (16) The communication device according to any one of (1) to (12), wherein the control unit notifies the application of delay information regarding timing at which the application will transmit the second packet in accordance with the delay characteristics. (17) The communication device according to (16), wherein the control unit converts timing of uplink resources into time. (18) The communication device according to any one of (1) to (17), wherein the control unit determines that preparation for transmission is completed when the second packet is stored in a transmission buffer of the communication unit.(19) A base station comprising: a control unit that receives a first packet from a sender of the first packet, acquires delay information from a communication device that transmits the first packet to a destination, and allocates uplink resources to the communication device in accordance with the delay information, wherein the communication device measures a delay characteristic from when the sender of the first packet transmits the first packet to when the communication device completes preparation for transmission of a second packet corresponding to the first packet, and generates the delay information based on the delay characteristic. (20) A terminal device having an application and a communication device, wherein the communication device comprises: a communication unit that receives the first packet from the sender of the first packet and transmits the first packet to a destination, and a control unit that measures a delay characteristic from when the sender of the first packet transmits the first packet to when the communication unit completes preparation for transmission of a second packet corresponding to the first packet, and notifies at least one of a base station and the application of delay information based on the delay characteristic. (21) A communication method for a communication device installed in a terminal device, comprising: a communication unit receiving a first packet from a sender of the first packet and transmitting the first packet to a destination, measuring a delay characteristic from when the sender of the first packet transmits the first packet to when the communication unit completes preparation for transmission of a second packet corresponding to the first packet, and notifying at least one of a base station and an application installed in the terminal device of delay information based on the delay characteristic. (22) A communication method comprising: receiving the first packet from the sender of the first packet and acquiring delay information from a communication device that transmits the first packet to a destination, and allocating uplink resources to the communication device according to the delay information, wherein the communication device measures a delay characteristic from when the sender of the first packet transmits the first packet to when the communication device completes preparation for transmission of a second packet corresponding to the first packet, and generates the delay information based on the delay characteristic.

[0423] 10 Application server 11, 21 Communication unit 12, 22, 32, 42 Storage unit 13, 23, 33, 43 Control unit 20 Information processing device 30 Base station 31, 41 Wireless communication unit 40 Wireless communication device 50 Application client 400 Terminal device

Claims

1. A communications device mounted on a terminal device, comprising: a communications unit that receives a first packet from a sender of the first packet and transmits the first packet to a destination; and a control unit that measures delay characteristics from when the sender of the first packet transmits the first packet until the communications unit completes preparations to transmit a second packet corresponding to the first packet, and notifies a base station and / or an application mounted on the terminal device of delay information based on the delay characteristics.

2. The communication device according to claim 1, wherein the control unit measures the delay characteristics when the first packet is downlink data transmitted by the base station and the second packet is uplink data corresponding to the downlink data.

3. The communication device according to claim 1, wherein the control unit measures the delay characteristic from when downlink data is received from the base station until preparation for transmission of uplink data corresponding to the downlink data is complete.

4. The communication device according to claim 1, wherein the control unit measures the delay characteristics based on an instruction from the base station.

5. The communication device according to claim 1, wherein the control unit measures the delay characteristics using downlink data transmitted from the base station and uplink data corresponding to the downlink data after receiving an instruction from the base station to measure the delay characteristics.

6. The communication device according to claim 1, wherein the control unit measures the delay characteristics using downlink data having a predetermined DCI and uplink data corresponding to the downlink data.

7. The communication device according to claim 1, wherein the control unit measures the delay characteristics using downlink data having a predetermined QoS identifier and uplink data corresponding to the downlink data.

8. The communication device according to claim 7, wherein the control unit measures the delay characteristics using the uplink data having the same QoS identifier as the predetermined QoS identifier contained in the downlink data.

9. The communication device according to claim 7, wherein the predetermined QoS identifier is a QoS identifier for measuring the delay characteristic.

10. The communication device according to claim 1, wherein the control unit transmits uplink data corresponding to the downlink data using uplink resources set by the base station in accordance with the transmission period of the downlink data and the delay information.

11. The communication device according to claim 1, wherein the control unit measures, as the delay characteristic, a delay time from when the application transmits uplink data until when the communication unit completes preparations to transmit the uplink data.

12. The communication device according to claim 11, wherein the control unit measures the delay characteristics according to the time when the application transmits the uplink data and the time when the communication unit completes preparations for transmitting the uplink data.

13. The communications device of claim 11, wherein the delay information includes an adjustment amount for uplink resources.

14. The communication device according to claim 1, wherein the control unit notifies the base station of delay information regarding allocation of resources to be used for transmitting the second packet after preparation for transmission of the second packet is completed, in accordance with the delay characteristics.

15. The communication device according to claim 1, wherein the control unit notifies the application of delay information relating to the timing at which the application transmits the second packet, in accordance with the delay characteristics.

16. The communications device of claim 15, wherein the control unit converts timing of uplink resources into time.

17. The communication device according to claim 1, wherein the control unit determines that the preparation for transmission is complete when the second packet is stored in an uplink buffer of the communication unit.

18. A base station comprising: a control unit that receives a first packet from a sender of the first packet, acquires delay information from a communication device that transmits the first packet to a destination, and allocates uplink resources to the communication device according to the delay information; wherein the communication device measures delay characteristics from when the sender of the first packet transmits the first packet to when the communication device completes preparations to transmit a second packet corresponding to the first packet, and generates the delay information based on the delay characteristics.

19. A terminal device having an application and a communication device, wherein the communication device comprises: a communication unit that receives a first packet from a sender of the first packet and transmits the first packet to a destination; and a control unit that measures a delay characteristic from when the sender of the first packet transmits the first packet to when the communication unit completes preparations to transmit a second packet corresponding to the first packet, and notifies a base station and / or the application of delay information based on the delay characteristic.

20. A communication method for a communication device installed in a terminal device, comprising: a communication unit receiving a first packet from a sender of the first packet and transmitting the first packet to a destination; measuring a delay characteristic from when the sender of the first packet transmits the first packet until the communication unit completes preparations for transmitting a second packet corresponding to the first packet; and notifying at least one of a base station and an application installed in the terminal device of delay information based on the delay characteristic.

21. A communication method comprising: receiving a first packet from a sender of the first packet, and acquiring delay information from a communication device that transmits the first packet to a destination; and allocating uplink resources to the communication device according to the delay information, wherein the communication device measures a delay characteristic from when the sender of the first packet transmits the first packet to when the communication device completes preparations for transmitting a second packet corresponding to the first packet, and generates the delay information based on the delay characteristic.

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