Communication device, base station, and communication method

Abstract

This communication device comprises a transmission control unit that transmits a trigger signal for extending or stopping repeated transmission, which is started on demand, to a communication point that executes the repeated transmission of at least one of a first signal or first notification information.

Description

Communication device, base station, and communication method

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

[0002] The development of technologies related to wireless communication such as cellular communication has been actively carried out. In recent years, by arranging a large number of communication nodes (for example, base stations and / or antennas) that terminal devices access in a communication environment, or by arranging various communication nodes in a communication environment, studies on technologies for improving communication performance have been initiated. For example, in recent years, studies on a cell-free network that dispenses with the concept of a conventional cell have been initiated.

[0003] 3GPP, RP-234065, “New WID: Enhancements of network energy savings for NR,” 3GPP TSG RAN Meeting #102, December 2024

[0004] However, simply arranging a large number of or various communication nodes in a communication environment does not necessarily achieve high-performance wireless communication (for example, high resource utilization efficiency, large capacity, high speed, low latency, high reliability, high density, multiple simultaneous connections, power saving, or low processing load). For example, in a communication environment where a large number of or various communication nodes exist, multiple communication nodes may interfere with each other, and as a result, high communication performance may not be achieved.

[0005] Therefore, the present disclosure proposes a communication device, a base station, and a communication method capable of achieving high communication performance.

[0006] Note that the above problems or objectives are only one of the multiple problems or objectives that can be solved or achieved by the multiple embodiments disclosed in this specification.

[0007] To solve the above problems, a communication device according to one embodiment of the present disclosure includes a transmission control unit that transmits a trigger signal for extending or stopping the repeated transmission to a communication point that executes the repeated transmission of at least one of a first signal and first notification information, which is a repeated transmission started on demand.

[0008] This is a diagram illustrating the outline of an embodiment. This is a diagram showing an example of the configuration of a communication system according to an embodiment. This is a diagram showing the configuration of a management device according to an embodiment. This is a diagram showing the configuration of a base station according to an embodiment. This is a diagram showing the configuration of a relay station according to an embodiment. This is a diagram showing the configuration of a terminal device according to an embodiment. This is a diagram showing an example of a communication system according to an embodiment. This is a diagram illustrating power concentration technology to a specific point (point forming). This is a diagram showing an example of point forming with a single antenna having a large number of antenna elements. This is a diagram illustrating the near-field and far-field. This is a diagram showing the Fraunhofer distance which is the boundary between the near-field and the far-field. This is a diagram showing an example of point forming in a distributed antenna environment. This is a sequence diagram showing an example of initial access processing. This is a diagram showing a collision-based random access procedure. This is a diagram showing a non-collision-based random access procedure. This is a diagram showing a two-step random access procedure. This is a schematic diagram showing an example of a system architecture according to an embodiment. This is a diagram showing an example of a timeline related to the transmission of an on-demand first signal / first broadcast information. This is a diagram showing another example of a timeline related to the transmission of an on-demand first signal / first broadcast information. This is a diagram showing an example of a timeline related to the transmission of an on-demand first signal / first broadcast information. This is a diagram showing another example of a timeline related to the transmission of an on-demand first signal / first broadcast information. This is a sequence diagram showing the communication process related to sequence example 1 of the first embodiment. This is a sequence diagram showing the communication process related to sequence example 2 of the first embodiment. This is a sequence diagram showing the communication process related to sequence example 3 of the first embodiment. This is a sequence diagram showing the communication process related to sequence example 4 of the first embodiment. This is a sequence diagram showing the communication process related to sequence example 5 of the first embodiment. This is a sequence diagram showing the communication process related to sequence example 1 of the second embodiment. This is a sequence diagram showing the communication process related to sequence example 2 of the second embodiment. This is a sequence diagram showing the communication process related to sequence example 3 of the second embodiment. This is a sequence diagram showing the communication process related to sequence example 4 of the second embodiment. This is a sequence diagram showing the communication process related to sequence example 5 of the second embodiment. This is a sequence diagram showing the communication process related to sequence example 1 of the third embodiment.This is a sequence diagram showing the communication processing according to sequence example 2 of the third embodiment. This is a sequence diagram showing an example of initial access processing according to the first method. This is a sequence diagram in which the two base stations shown in Figure 34A are rewritten based on the communication point. This is a sequence diagram showing an example of initial access processing according to the second method. This is a sequence diagram in which the two base stations shown in Figure 35A are rewritten based on the communication point. This is a sequence diagram showing an example of initial access processing according to the third method. This is a sequence diagram in which the two base stations shown in Figure 36A are rewritten based on the communication point. This is a sequence diagram showing an example of initial access processing according to the fourth method. This is a sequence diagram in which the two base stations shown in Figure 37A are rewritten based on the communication point.

[0009] The embodiments of this disclosure will be described in detail below with reference to the drawings. In the following embodiments, the same parts will be denoted by the same reference numerals to avoid redundant descriptions.

[0010] Furthermore, in this specification, the expression "at least one of" accompanied by an enumeration of elements is understood to mean that the enumerated elements are the choices. For example, "at least one of A, B, and C" means "(A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C)." "at least one of A, B, or C" and "at least one of A, B, and / or C" are similar to "at least one of A, B, and C." Here, A, B, and C are all arbitrary expressions (e.g., word, phrase, clause, term, or item).

[0011] Furthermore, in this specification and drawings, multiple components having substantially the same functional configuration may be distinguished by adding different numbers after the same reference numeral. For example, multiple components having substantially the same functional configuration may be distinguished as communication point P as needed. １ , P ２ , and P ３ They are distinguished in this way. However, if there is no need to particularly distinguish each of multiple components that have substantially the same functional configuration, only the same code is assigned. For example, communication point P １ , P ２ , and P ３ When there is no particular need to distinguish between them, they are simply referred to as communication point P.

[0012] The one or more embodiments (including examples and modifications) described below can each be implemented independently. On the other hand, at least some of the embodiments described below may be implemented in appropriate combination with at least some of the other embodiments. These embodiments may contain novel features that differ from each other. Therefore, these embodiments may contribute to solving different objectives or problems and may produce different effects.

[0013] This disclosure will be described in the following order of items: 1. Overview 2. Configuration of the communication system 2-1. Example of the configuration of the management device 2-2. Example of the configuration of the base station 2-3. Example of the configuration of the relay station 2-4. Example of the configuration of the terminal device 3. Communication points 3-1. Definition of a communication point 3-2. Specific examples of the communication system 3-3. Point forming 4. Initial access control 4-1. Basic procedure 4-2. Random access procedure 4-3. Initial access control in cell-free communication 5. Operation of the communication system 5-1. System architecture 5-2. Signal configuration 5-3. Overview of the operation of the communication system 5-4. First embodiment 5-5. Second embodiment 5-6. Third embodiment 6. Application to initial access in cell-free 6-1. First method 6-2. Second method 6-3. Third method 6-4. Fourth method 7. Modifications 8. Musubi

[0014] <<1. Overview>> Development of wireless communication technologies such as cellular communication is actively underway. Currently, 3GPP (registered trademark) is beginning discussions toward B5G (Beyond 5G) and 6G (6th Generation Mobile Communication System) in parallel with the formulation of 5G specifications.

[0015] Conventional cellular communications have controlled communication in units of a single base station (including a TRP (Transmission and Reception Point)) called a cell, which is called the communication range (communication coverage). However, with B5G and 6G, in addition to millimeter waves, the operation of systems in high-frequency bands such as terahertz waves is expected. Communication using high-frequency bands has a shorter propagation distance compared to communication using low-frequency bands. Therefore, it is expected that the communication range (communication coverage) of base stations will be smaller than before in B5G and 6G.

[0016] Furthermore, future wireless communications are expected to feature a greater diversity of communication nodes. For example, in 5G, in addition to base stations, it is anticipated that overhanging antennas called TRPs will be used as communication nodes. Moreover, it is anticipated that IAB (Integrated Access and Backhaul) nodes (i.e., base station relays) will be used as communication nodes in 5G. Additionally, it is anticipated that NTN (Non-terrestrial Network) nodes (e.g., communication satellites) will be used as communication nodes in 5G.

[0017] In B5G and 6G, further diversification of communication nodes is expected to be pursued with the aim of supporting high frequency bands and / or reducing CAPEX / OPEX. For example, in B5G and 6G, smart repeaters called RIS (Reconfigurable Intelligent Surface) are expected to be used as communication nodes. In addition, terminal-to-terminal relays are also expected to be used in B5G and 6G. Conventional communication nodes were either fully controllable communication nodes (e.g., base stations and / or IAB nodes) or communication nodes that could not be controlled at all (e.g., RF (Radio Frequency) repeaters). However, in the future, it is expected that communication nodes in which some control items can be controlled will also be used.

[0018] To deploy a communication area across a wide area using communication nodes with narrowed communication coverage, an extremely large number of communication nodes are required. Therefore, it is expected that conventional cell design will become very difficult. Furthermore, the diversification of communication nodes will also increase the difficulty of cell design. For this reason, it is expected that cell-free networks will be introduced as a basic function in B5G and 6G. A cell-free network is a wireless network that eliminates cell boundaries in a conventional cell configuration (cellular network) centered on a base station. A cell-free network enables an optimal communication environment that does not depend on the positional relationship between the user and the base station. By realizing a cell-free network, the network can be operated efficiently with low power consumption. In addition, by realizing a cell-free network, it becomes possible to efficiently provide information on a user-by-user basis.

[0019] However, simply deploying a large number or diverse range of communication nodes in a communication environment does not guarantee high communication performance (e.g., high resource utilization efficiency, large capacity, high speed, low latency, high reliability, high density, many simultaneous connections, low power consumption, or low processing load) in wireless communication. For example, in a communication environment with a large number or diverse range of communication nodes, multiple communication nodes may interfere with each other, potentially resulting in a failure to achieve high communication performance.

[0020] In environments with numerous or diverse communication nodes, it is generally considered necessary to keep communication nodes in an "off" state (also known as a stopped or sleep state) and wake them up as needed to avoid interference. In other words, in environments with numerous or diverse communication nodes, it is considered necessary to operate communication nodes on demand.

[0021] For example, 3GPP is discussing a technology that enables power saving by putting inactive base stations into sleep mode by making the transmission of the first signal and / or the first broadcast information (e.g., SSB (SS (Synchronization Signal) / PBCH (Physical Broadcast Channel) block) and / or SIB1 (System Information Block 1)) on demand. This technology has the potential to become a fundamental technology for initial access in self-free networks.

[0022] However, if a communication node is operated on demand, it will essentially remain in an off state. In other words, if a communication node is operated on demand, it may return to an off state at a time unintended by the user (terminal device). In this case, the communication control of the communication device (for example, initial access control of the terminal device) may fail. To prevent this, the terminal device must perform the initial access to the communication node from the first step (for example, from waking up the communication node). This results in unnecessary steps and wasted resources, which may prevent high-performance wireless communication from being achieved.

[0023] Figure 1 is a diagram illustrating the outline of this embodiment. For example, a communication environment may have multiple communication points (communication point P shown in Figure 1). １ ~P ＮSuppose there is a communication point. The communication point is, for example, a communication node (e.g., a base station, a relay station, or an antenna) accessible to a terminal device. Each of the plurality of communication points can start on-demand the repeated transmission of at least one of the first signal and the first notification information. For example, when the communication point receives an initial trigger signal (hereinafter simply referred to as an initial trigger) instructing the start of repeated transmission from another communication device, it starts the repeated transmission of at least one of the first signal and the first notification information.

[0024] Here, suppose that one of the plurality of communication points (in the example of FIG. 1, communication point P Ａ ) wakes up by an initial trigger from the first terminal device (in the example of FIG. 1, UE ２ ). Then, after waking up, suppose that the communication point starts transmitting the first signal and / or the first notification information. In this state, suppose that the second terminal device (in the example of FIG. 1, UE Ｂ ) attempts to make an initial access to that communication point. At this time, if the communication point transitions to the off state during the execution of the initial access process of the second terminal device, the initial access control of the second terminal device may fail. In this case, the second terminal device has to retry the initial access, so high-performance wireless communication cannot be realized.

[0025] Therefore, in the present embodiment, a communication device (e.g., UE shown in FIG. 1 Ｂ ) transmits a trigger signal (hereinafter referred to as an extension trigger signal or simply an extension trigger) for extending the repeated transmission to a communication point (e.g., communication point P shown in FIG. 1 ２ ) that executes the repeated transmission of at least one of the first signal and the first notification information (e.g., periodic transmission). When the communication point receives the extension trigger signal, it extends the repeated transmission.

[0026] This prevents the communication point from returning to the "off" state at an unintended time, thus reducing the likelihood of the communication device failing to perform communication control (e.g., initial access control for terminal devices). Furthermore, the communication device no longer needs to perform the initial access procedure to access the communication point; in other words, it can eliminate unnecessary steps. As a result, high-performance wireless communication is achieved.

[0027] The trigger signal transmitted by the communication device to the communication point is not limited to an extension trigger signal. For example, the communication device may transmit a trigger signal to the communication point to stop the repeated transmission of at least one of the first signal and the first broadcast information (hereinafter referred to as a stop trigger signal, or simply a stop trigger). The communication point may stop repeated transmission when it receives a stop trigger signal.

[0028] This allows the communication point to return to the "off" state when repeated transmission is no longer necessary, resulting in high-performance wireless communication (e.g., low power consumption or low processing load).

[0029] Having outlined the basics of this embodiment, the communication system 1 of this embodiment will now be described in detail.

[0030] <<2. Configuration of the Communication System>> First, the configuration of the communication system 1 will be explained. Figure 2 is a diagram showing an example of the configuration of the communication system 1 according to this embodiment. The communication system 1 comprises a management device 10, a base station 20, a relay station 30, and a terminal device 40. The communication system 1 provides a wireless network (mobile network) that enables mobile communication to users through the coordinated operation of each wireless communication device that constitutes the communication system 1.

[0031] The wireless network (mobile network) in this embodiment may be, for example, a cellular network / cell-free network composed of a wireless access network (RAN) and a core network (CN). A cell-free network is a wireless network that eliminates cell boundaries in a conventional cell configuration (cellular network) centered on a base station. The wireless network (mobile network) may also include terminal devices 40. In this embodiment, a wireless communication device is a device that has wireless communication functionality, and in the example in Figure 2, this corresponds to a base station 20, a relay station 30, and a terminal device 40.

[0032] The communication system 1 may include multiple management devices 10, base stations 20, relay stations 30, and terminal devices 40. In the example in Figure 2, the communication system 1 includes multiple management devices 10. １ and 10 ２ It is equipped with, and as base station 20, １ , 20 ２ , and 20 ３ It is equipped with a relay station 30. １ and 30 ２ It is equipped with terminal device 40 as terminal device 40 １ , 40 ２ , and 40 ３ It is equipped with.

[0033] The terminal device 40 may be configured to connect to the network using radio access technologies (RATs) such as LTE (Long Term Evolution), NR (New Radio), B5G (Beyond 5G), 6G, Wi-Fi, and Bluetooth®. In this case, the terminal device 40 may be configured to use different radio access technologies (wireless communication methods). For example, the terminal device 40 may be configured to use NR and Wi-Fi. Also, the terminal device 40 may be configured to use different cellular communication technologies / cell-free communication technologies (e.g., LTE, NR, B5G, or 6G). In the following description, the terminal device 40 may be referred to as UE (User Equipment) 40.

[0034] LTE and NR are types of cellular communication technologies that enable mobile communication for terminal devices by arranging multiple cell-like areas covered by devices with electromagnetic wave transmission and reception capabilities (e.g., base stations or TRPs (Transmission and Reception Points)). B5G and 6G are types of cellular / cell-free communication technologies that have the potential to enable mobile communication for terminal devices. Cell-free communication technology is a technology that eliminates cell boundaries in conventional cellular networks. Cell-free communication technology may also be considered a type of cellular communication technology. In this case, it is possible to appropriately replace "cellular" with "cell-free" or vice versa in the following explanation.

[0035] In the following explanation, "LTE" includes LTE-A (LTE-Advanced), LTE-A Pro (LTE-Advanced Pro), and EUTRA (Evolved Universal Terrestrial Radio Access). Furthermore, "NR" includes NRAT (New Radio Access Technology) and FEUTRA (Further EUTRA). A single base station or TRP may manage multiple cells. In the following explanation, cells corresponding to LTE are referred to as LTE cells, and cells corresponding to NR are referred to as NR cells.

[0036] NR (Radio Wave) is the next generation (fifth generation) wireless access technology following LTE (fourth generation communication including LTE-Advanced and LTE-Advanced Pro). NR is a wireless access technology that can support various use cases, including eMBB (Enhanced Mobile Broadband), mMTC (Massive Machine Type Communications), and URLLC (Ultra-Reliable and Low Latency Communications). NR was standardized in 3GPP® Rel-15 as a technical framework to address the usage scenarios, requirements, and deployment scenarios in these use cases. Furthermore, 3GPP is considering next-generation technologies, including enhancements to the NR standard. For example, in Rel-19, standardization activities are underway for the next-generation communication standard, 6G (B5G (Beyond 5G)).

[0037] 6G is the next generation of cellular / cell-free communication technology following NR (Non-Reactive Network) and 5GS (5G system), which are fifth-generation mobile communication technologies. 6G requires the simultaneous realization of multiple axes: high speed, large capacity, low latency, high reliability, and massive simultaneous connections. 6G includes wireless access technology and network technologies between base stations, core networks, and data networks. Furthermore, 6G includes technologies for the extreme connectivity of eMBB, mMTC, and URLLLC, which were key use cases or requirements in NR. 6G also includes new technologies in new areas. For example, 6G may include technologies related to AI (Cognitive Network, AI Native Air Interface), sensing (Radar / RF sensing, including network as a sensor), and terahertz communication.

[0038] The wireless network described above or below may support at least one of the following radio access technologies (RATs): LTE, NR, B5G, 6G, etc. LTE, NR, B5G, and 6G are types of cellular / cell-free communication technologies. The wireless access method used by communication system 1 is not limited to LTE, NR, B5G, or 6G, but may also be other wireless access methods such as W-CDMA (Wideband Code Division Multiple Access) or cdma2000 (Code Division Multiple Access 2000).

[0039] Furthermore, the base station 20 and the relay station 30 may be ground stations or non-ground stations. Non-ground stations may be satellite stations or aircraft stations. If a non-ground station is a satellite station, the wireless network may be a bent-pipe (transparent) type mobile satellite communication system.

[0040] In this embodiment, "ground station" and "ground base station" refer to base stations and relay stations installed on the ground. Here, "ground" is a broad term that includes not only land but also underground, on water, and underwater. In the following description, "ground station" may be replaced with "gateway."

[0041] Furthermore, LTE base stations are sometimes referred to as eNodeB (Evolved Node B) or eNB. Similarly, NR base stations are sometimes referred to as gNodeB or gNB. 6G base stations are sometimes referred to as 6G NodeB (6GNB). In addition, for LTE, NR, and 6G, terminal equipment (also called mobile stations or terminals) is sometimes referred to as UE (User Equipment). Terminal equipment is a type of communication device and is also called a mobile station or terminal.

[0042] Furthermore, the terminal device 40 may be able to connect to the network using wireless access technologies (wireless communication methods) other than LTE, NR, B5G, 6G, Wi-Fi, and Bluetooth. For example, the terminal device 40 may be able to connect to the network using LPWA (Low Power Wide Area) communication. Also, the terminal device 40 may be able to connect to the network using a proprietary wireless communication standard.

[0043] Here, LPWA communication refers to wireless communication that enables low-power, wide-area communication. For example, LPWA wireless refers to IoT (Internet of Things) wireless communication using specified low-power wireless (e.g., 920 MHz band) or ISM (Industry-Science-Medical) band. LPWA wireless may also include LTE-M and / or C-IoT (Cellular IoT) represented by NB-IoT, which operate in the cellular frequency band. The LPWA communication used by the terminal device 40 may conform to the LPWA standard. The LPWA standard may be at least one of, for example, ELTRES, ZETA, SIGFOX, LoRaWAN, LTE-M, and NB-IoT. Of course, the LPWA standard is not limited to these, and other LPWA standards may also be used.

[0044] Each wireless communication device shown in Figure 2 can be considered a device in a logical sense. That is, a part of each wireless communication device may be implemented using a virtual machine (VM), a container such as Docker, etc., and these may be implemented on the same physical hardware.

[0045] In this embodiment, the concept of a wireless communication device includes not only portable mobile devices (terminal devices) such as mobile terminals, but also devices installed on structures or mobile objects. The structure or mobile object itself may be considered a wireless communication device. Furthermore, the concept of a wireless communication device includes not only the terminal device 40, but also the base station 20 and the relay station 30. A wireless communication device is a type of processing device or information processing device. A wireless communication device can also be described as a transmitting device or a receiving device.

[0046] The configurations of each wireless communication device constituting communication system 1 are described in detail below. Note that the configurations of each wireless communication device shown below are merely examples. The configurations of each wireless communication device may differ from those shown below.

[0047] <2-1. Example of Management Device Configuration> Next, an example of the configuration of the management device 10 will be explained.

[0048] The management device 10 is an information processing device (computer) that manages the wireless network. For example, the management device 10 is an information processing device that manages the communications of the base station 20.

[0049] The management device 10 may be a device that constitutes the core network CN. For example, the management device 10 may be a device that functions as an MME (Mobility Management Entity). Alternatively, the management device 10 may be a device that functions as an AMF (Access and Mobility Management Function) and / or an SMF (Session Management Function). The MME, AMF, and SMF are Control Plane Network Function nodes in the core network CN. The management device 10 may also be a device that functions as a Control Plane Network Function (6G CPNF) in 6G. The 6G CPNF may consist of one or more logical nodes.

[0050] Of course, the functions of the management device 10 are not limited to MME, AMF, SMF, and 6G CPNF. The management device 10 may also be a device that has the functions of NSSF (Network Slice Selection Function), AUSF (Authentication Server Function), PCF (Policy Control Function), and UDM (Unified Data Management). Furthermore, the management device 10 may also be a device that has the function of HSS (Home Subscriber Server).

[0051] Furthermore, the management device 10 may also have gateway functionality. For example, the management device 10 may function as an S-GW (Serving Gateway) or a P-GW (Packet Data Network Gateway). The management device 10 may also function as a UPF (User Plane Function). In this case, the management device 10 may have multiple UPFs. The management device 10 may also be a device that functions as a User Plane Network Function (6G UPNF) in 6G.

[0052] The core network (CN) consists of multiple network functions, each of which may be aggregated in a single physical device or distributed across multiple physical devices. In other words, the management device 10 can be distributed across multiple devices. Furthermore, this distributed arrangement may be controlled to be performed dynamically. The base station 20, the relay station 30, and the management device 10 constitute a single network and provide wireless communication services to the terminal device 40. The management device 10 is connected to the internet, and the terminal device 40 can use various services provided via the internet through the base station 20 and / or the relay station 30.

[0053] Note that the management device 10 does not necessarily have to be a device that constitutes the core network CN. For example, suppose the core network CN is the core network of W-CDMA (Wideband Code Division Multiple Access) or cdma2000 (Code Division Multiple Access 2000). In this case, the management device 10 may be a device that functions as an RNC (Radio Network Controller).

[0054] Figure 3 shows the configuration of the management device 10 according to this embodiment. The management device 10 comprises a communication unit 11, a storage unit 12, and a control unit 13. The configuration shown in Figure 3 is a functional configuration, and the hardware configuration may differ. Furthermore, the functions of the management device 10 may be implemented by statically or dynamically distributing them across multiple physically separated configurations. The management device 10 may be composed of multiple server devices.

[0055] The communication unit 11 is a communication interface for communicating with a wireless communication device (for example, a base station 20). The communication unit 11 may be a network interface or an equipment connection interface. The communication unit 11 may be a LAN (Local Area Network) interface such as a NIC (Network Interface Card), or a USB interface configured by a USB (Universal Serial Bus) host controller or a USB port. The communication unit 11 may be a wired interface or a wireless interface. The communication unit 11 is controlled by the control unit 13.

[0056] The memory unit 12 is a read / write storage device such as DRAM (Dynamic Random Access Memory), SRAM (Static Random Access Memory), flash memory, or a hard disk. The memory unit 12 stores, for example, the connection status of the terminal device 40. The memory unit 12 stores the RRC (Radio Resource Control) status and ECM (EPS Connection Management) or 5G System CM (Connection Management) status of the terminal device 40. The memory unit 12 may also function as a home memory that stores the location information of the terminal device 40.

[0057] The control unit 13 is a controller that controls each part of the management device 10. The control unit 13 may be implemented by a processor such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). More specifically, the control unit 13 may be implemented by the processor executing various programs stored in the internal storage device of the management device 10 using RAM (Random Access Memory) or the like as a working area. The control unit 13 may be implemented by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). Alternatively, the control unit 13 may be implemented by a GPU (Graphics Processing Unit). A CPU, MPU, ASIC, FPGA, and GPU can all be considered as controllers. The control unit 13 may also be composed of multiple physically separated objects. For example, the control unit 13 may be composed of multiple semiconductor chips.

[0058] The operation of the control unit 13 may be the same as the operation of the control unit (control unit 23, control unit 33, or control unit 43) of the base station 20, relay station 30, or terminal device 40.

[0059] <2-2. Example of Base Station Configuration> Next, an example of the configuration of base station 20 will be explained.

[0060] Base station 20 is a wireless communication device that communicates wirelessly with other wireless communication devices (for example, a relay station 30, a terminal device 40, or another base station 20). Base station 20 may communicate wirelessly with terminal device 40 via relay station 30, or it may communicate wirelessly with terminal device 40 directly.

[0061] Base station 20 is a device equivalent to a wireless base station (e.g., Base Station, Node B, eNB, gNB, or 6GNB) or a wireless access point. In the following description, base station 20 may be referred to as BS (Base Station), Node B, eNB, gNB, 6GNB, or BS20.

[0062] Base station 20 may be a radio relay station (for example, a relay station 30 described later). Base station 20 may be an optical extension device called an RRH (Remote Radio Head). Base station 20 may be a receiving station such as an FPU (Field Pickup Unit). Base station 20 may be an IAB (Integrated Access and Backhaul) donor node or IAB relay node that provides radio access lines and radio backhaul lines by time division multiplexing, frequency division multiplexing, or spatial division multiplexing.

[0063] The wireless access technology used by base station 20 may be cellular communication technology / cell-free communication technology. The wireless access technology used by base station 20 may be wireless LAN technology. The wireless access technology used by base station 20 may be LPWA (Low Power Wide Area) communication technology. However, the wireless access technology used by base station 20 is not limited to these, and other wireless access technologies may be used. The wireless communication used by base station 20 may be wireless communication using millimeter waves or wireless communication using terahertz waves. The wireless communication used by base station 20 may be wireless communication using radio waves or wireless communication using infrared or visible light (optical wireless). In addition, base station 20 may be capable of NOMA (Non-Orthogonal Multiple Access) communication with terminal device 40. Here, NOMA communication refers to communication using non-orthogonal resources (transmission, reception, or both). Base station 20 may also be capable of NOMA communication with other base stations 20.

[0064] Furthermore, base station 20 may be able to communicate with the core network via a base station-core network interface (e.g., NG Interface, S1 Interface, etc.). This interface may be either wired or wireless. Also, base stations may be able to communicate with other base stations via an inter-base station interface (e.g., Xn Interface, X2 Interface, F1 Interface, etc.). This interface may be either wired or wireless.

[0065] The concept of a base station (also called "base station equipment") includes not only donor base stations but also relay base stations (also called "relay stations"). A relay base station may be any one of the following: an RF Repeater, a Smart Repeater, or an Intelligent Surface. Furthermore, the concept of a base station may also include roadside units (RSUs). In addition, the concept of a base station may include not only structures equipped with base station functions but also equipment installed on those structures.

[0066] Structures include buildings such as skyscrapers, houses, transmission towers, train stations, airports, ports, office buildings, school buildings, hospitals, factories, commercial facilities, and stadiums. The concept of structures also includes not only buildings but also non-building structures such as tunnels, bridges, dams, walls, and steel columns, as well as equipment such as cranes, gates, and wind turbines. The concept of structures also includes not only structures on land (on the surface in the narrow sense) or underground, but also structures on water such as piers or megafloats, and underwater structures such as oceanographic observation equipment. A base station can also be described as an information processing device.

[0067] Base station 20 may be a donor station or a relay station. Furthermore, base station 20 may 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, base station 20 may be a device installed on a mobile device or the mobile device itself. For example, a relay station with mobility can be considered a base station 20 as a mobile station. Additionally, devices that are inherently mobile and equipped with base station functions (or at least some of the functions of a base station), such as vehicles, UAVs (Unmanned Aerial Vehicles) represented by drones, and smartphones, also qualify as base station 20 as a mobile station.

[0068] Here, the moving object may be a mobile device such as a smartphone or mobile phone. The moving object may also be a moving object that moves on land (ground in the narrow sense) (for example, a car, bicycle, bus, truck, motorcycle, train, or linear motor car), or a moving object that moves underground (for example, inside a tunnel) (for example, a subway). The moving object may also be a moving object that moves on water (for example, a passenger ship, cargo ship, or hovercraft), or a moving object that moves underwater (for example, a submersible boat, submarine, or unmanned submersible). The moving object may also be a moving object that moves within the atmosphere (for example, an airplane, airship, or drone).

[0069] Base station 20 may be a ground base station (ground station) installed on the ground. Base station 20 may be a base station located on a structure on the ground, or a base station installed on a mobile body moving on the ground. Base station 20 may be an antenna installed on a structure such as a building and a signal processing device connected to that antenna. Base station 20 may be the structure or the mobile body itself. "Ground" refers to ground in a broad sense, including not only land (ground in the narrow sense) but also underground, on water, and underwater. Base station 20 is not limited to a ground base station. If communication system 1 is a satellite communication system, base station 20 may be an aircraft station. From the perspective of a satellite station, an aircraft station located on Earth is a ground station.

[0070] The base station 20 is not limited to a ground station. The base station 20 may be a non-ground base station (non-ground station) capable of floating in the air or space. The base station 20 may be an aircraft station or a satellite station.

[0071] A satellite station is a radio communication device capable of floating outside the atmosphere. A satellite station may be a device mounted on a spacecraft such as an artificial satellite, or it may be the spacecraft itself. A spacecraft is a mobile object that moves outside the atmosphere. A spacecraft may be at least one of the following: an artificial satellite, a spacecraft, a space station, and a probe. Of course, a spacecraft may also be an artificial celestial body other than these. The satellite that becomes a satellite station may be a low Earth orbit (LEO) satellite, a medium Earth orbit (MEO) satellite, a geostationary Earth orbit (GEO) satellite, or a highly elliptical orbit (HEO) satellite. A satellite station may be a device mounted on a low Earth orbit satellite, a medium Earth orbit satellite, a geostationary satellite, or a highly elliptical orbit satellite.

[0072] An aircraft station is a radio communication device capable of floating within the atmosphere of an aircraft or similar vessel. An aircraft station may be a device mounted on an aircraft or similar vessel, or it may be the aircraft itself. The concept of an aircraft includes not only heavy aircraft such as airplanes or gliders, but also light aircraft such as balloons or airships. The concept of an aircraft also includes not only heavy or light aircraft, but also rotary-wing aircraft such as helicopters or autogyros. An aircraft station, or an aircraft on which an aircraft station is mounted, may be an unmanned aerial vehicle such as a drone.

[0073] The concept of unmanned aerial vehicles includes unmanned aircraft systems (UAS) and tethered UAS. It also includes lighter than air UAS (LTA) and heavier than air UAS (HTA). Furthermore, it includes high-altitude UAS platforms (HAPs).

[0074] The coverage size of the base station 20 may be relatively large, such as a macrocell, or relatively small, such as a picocell. The coverage size of the base station 20 may also be extremely small, such as a femtocell. The base station 20 may have a beamforming function. The base station 20 may form cells or service areas for each beam. Furthermore, or alternatively, in addition to beamforming which gives directionality to the beam, the base station 20 may have a function that delivers the desired wave precisely to a predetermined point by further considering distance information from the base station 20's antenna. This function may be called beam focusing or point forming. The base station 20 may also be configured to acquire sensing data by performing sensing using the beam.

[0075] Figure 4 shows the configuration of a base station 20 according to this embodiment. The base station 20 comprises a wireless communication unit 21, a storage unit 22, and a control unit 23. However, the configuration shown in Figure 4 is a functional configuration, and the hardware configuration may differ. Furthermore, the functions of the base station 20 may be distributed and implemented across multiple physically separated configurations.

[0076] Note that the base station 20 does not necessarily have all of the above-mentioned or later-described configurations. Furthermore, the base station 20 may have configurations other than those described above or later.

[0077] The wireless communication unit 21 is a signal processing unit for wireless communication with other wireless communication devices (for example, at least one of a relay station 30, a terminal device 40, and another base station 20). The wireless communication unit 21 may be called a wireless transceiver or simply a transceiver. In this case, the wireless communication unit 21 may be a transceiver conforming to the specifications defined in the 3GPP (3rd Generation Partnership Project) Technical Specification (TS) (hereinafter referred to as a 3GPP transceiver). The 3GPP transceiver may be a 3G transceiver, a 4G (LTE) transceiver, a 5G (NR) transceiver, or a transceiver of a 5G or later generation (for example, 6G). The wireless communication unit 21 is controlled by the control unit 23. The wireless communication unit 21 supports one or more wireless access schemes. The wireless communication unit 21 may support at least one of NR, LTE, B5G (Beyond 5G), and 6G. The wireless communication unit 21 may support W-CDMA and cdma2000, in addition to NR, LTE, B5G, and 6G. The wireless communication unit 21 may also support automatic retransmission technologies such as HARQ (Hybrid Automatic Repeat reQuest). Some or all of the processing performed by the wireless communication unit 21 may be performed by the control unit 23.

[0078] The wireless communication unit 21 comprises a transmission processing unit 211, a reception processing unit 212, and an antenna 213. Alternatively, the wireless communication unit 21 may be considered as at least one of the transmission processing unit 211, the reception processing unit 212, and the antenna 213. The wireless communication unit 21 may include multiple transmission processing units 211, reception processing units 212, and antennas 213. If the wireless communication unit 21 supports multiple wireless access methods, each part of the wireless communication unit 21 may be configured separately for each wireless access method. The transmission processing unit 211 and the reception processing unit 212 may be configured separately for LTE, NR, B5G, and 6G. The antenna 213 may be composed of multiple antenna elements, for example, multiple patch antennas. The wireless communication unit 21 may have a beamforming function. For example, the wireless communication unit 21 may have a polarization beamforming function that uses vertical polarization (V polarization) and horizontal polarization (H polarization) (or a polarization beamforming function that uses dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical). The wireless communication unit 21 may also transmit the sensing signals described above or below.

[0079] The transmission processing unit 211 performs the transmission processing of downlink control information and downlink data. For example, the transmission processing unit 211 encodes the downlink control information and downlink data input from the control unit 23 using an encoding method such as block coding, convolutional coding, or turbo coding. Here, encoding may be performed using polar coding or LDPC coding (Low Density Parity Check Code). The transmission processing unit 211 then modulates the encoded bits with a predetermined modulation method (for example, BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), 16QAM (Quadrature Amplitude Modulation), 64QAM, 256QAM, or a higher-order multi-level modulation method). In this case, the signal points on the constellation do not necessarily need to be equidistant. The constellation may also be a non-uniform constellation (NUC). The transmission processing unit 211 then multiplexes the modulation symbols and downlink reference signals for each channel and places them in predetermined resource elements. The transmission processing unit 211 then performs various signal processing on the multiplexed signals. For example, the transmission processing unit 211 performs processing such as conversion to the frequency domain using the Fast Fourier Transform, addition of guard intervals (cyclic prefixes), generation of baseband digital signals, conversion to analog signals, quadrature modulation, upconversion, removal of extraneous frequency components, and power amplification. The signals generated by the transmission processing unit 211 are transmitted from the antenna 213.

[0080] The receiving processing unit 212 processes the uplink signal received via the antenna 213. For example, the receiving processing unit 212 performs down-conversion, removal of unwanted frequency components, amplification level control, quadrature demodulation, conversion to a digital signal, removal of guard intervals (cyclic prefixes), and extraction of frequency domain signals using Fast Fourier Transform on the uplink signal. Then, the receiving processing unit 212 separates the uplink channels and uplink reference signals, such as PUSCH (Physical Uplink Shared Channel) and PUCCH (Physical Uplink Control Channel), from the processed signal. The receiving processing unit 212 also demodulates the received signal using a modulation scheme such as BPSK or QPSK for the modulation symbols of the uplink channels. The modulation scheme used for demodulation may be 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 receiving processing unit 212 then performs decoding on the encoded bits of the demodulated uplink channel. The decoded uplink data and uplink control information are output to the control unit 23.

[0081] Antenna 213 is an antenna device that converts electric current and radio waves to each other. Antenna 213 may consist of one antenna element, for example, one patch antenna. Antenna 213 may consist of multiple antenna elements, for example, multiple patch antennas. If antenna 213 consists of multiple antenna elements, the wireless communication unit 21 may have a beamforming function. The wireless communication unit 21 may be configured to generate a directional beam by controlling the directivity of the radio signal using multiple antenna elements. Antenna 213 may be a dual-polarization antenna. If antenna 213 is a dual-polarization antenna, the wireless communication unit 21 may use vertical polarization (V polarization) and horizontal polarization (H polarization) (or dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical) when transmitting a radio signal. The wireless communication unit 21 may control the directivity of the transmitted radio signal using vertical polarization and horizontal polarization (or dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical). Furthermore, the wireless communication unit 21 may transmit and receive signals spatially multiplexed through multiple layers composed of multiple antenna elements.

[0082] The memory unit 22 is a read / write storage device such as DRAM, SRAM, flash memory, or a hard disk.

[0083] The control unit 23 is a controller that controls various parts of the base station 20. The control unit 23 controls the wireless communication unit 21 to perform wireless communication with other wireless communication devices (for example, a relay station 30, a terminal device 40, or another base station 20). The control unit 23 may be implemented by a processor such as a CPU or MPU. Specifically, the control unit 23 may be implemented by the processor executing various programs stored in the internal memory of the base station 20 using RAM or the like as a working area. The control unit 23 may be implemented by an integrated circuit such as an ASIC or FPGA. Furthermore, the control unit 23 may be implemented by a GPU. CPU, MPU, ASIC, FPGA, and GPU can all be considered as controllers. The control unit 23 may be composed of multiple physically separated objects. For example, the control unit 23 may be composed of multiple semiconductor chips.

[0084] The control unit 23 comprises at least one block, which consists of a transmission control unit 231 and a reception control unit 232. The control unit 23 may comprise multiple blocks of each type, or it may comprise only one of each type.

[0085] Each block constituting the control unit 23 (transmit control unit 231 to receive control unit 232) is a functional block that represents the function of the control unit 23. These functional blocks may be software blocks or hardware blocks. For example, each of the above-mentioned functional blocks may be a single software module implemented in software (including microprograms), or a single circuit block on a semiconductor chip (die). Of course, each functional block may also be a single processor or a single integrated circuit. The control unit 23 may be composed of functional units different from the above-mentioned functional blocks. The configuration method of the functional blocks is arbitrary. The operation of the control unit 23 may be the same as the operation of the control units (control unit 13, control unit 33, or control unit 43) of the management device 10, relay station 30, or terminal device 40.

[0086] In some embodiments, the base station 20 may be composed of a collection of multiple physical or logical devices. For example, the base station 20 in this embodiment may be distinguished into multiple devices such as a BBU (Baseband Unit) and an RU (Radio Unit). The base station 20 may be interpreted as a collection of these multiple devices. Furthermore, the base station may consist of either a BBU or an RU, or both. The BBU and RU may be connected by a predetermined interface, such as an eCPRI (enhanced Common Public Radio Interface).

[0087] RU may be rephrased as RRU (Remote Radio Unit) or RD (Radio DoT). RU may correspond to gNB-DU (gNB Distributed Unit), which will be described later. BBU may correspond to gNB-CU (gNB Central Unit), which will be described later. RU may be a device integrally formed with the antenna. The antenna of the base station 20, for example, an antenna integrally formed with the RU, may employ an Advanced Antenna System and support MIMO (Multiple-Input Multiple-Output) or beamforming, such as FD-MIMO. The antenna of the base station 20 may have, for example, 64 transmitting antenna ports and 64 receiving antenna ports.

[0088] 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. The RU may be equipped with two types of antenna panels: a horizontally polarized antenna panel and a vertically polarized antenna panel. The RU may be equipped with two types of antenna panels: a right-hand circularly polarized antenna panel and a left-hand circularly polarized antenna panel, or an antenna panel with a polarization direction of 45 degrees from the vertical and an antenna panel with a polarization direction of -45 degrees. Multiple antennas with multiple polarization directions may be mounted on a single antenna panel. The RU may form and control independent beams for each antenna panel.

[0089] Multiple base stations 20 may be connected to each other. One or more base stations 20 may be included in a radio access network (RAN). In this case, the base stations 20 may simply be referred to as RAN, RAN node, AN (Access Network), or AN node, etc. In LTE, RAN may be called EUTRAN (Enhanced Universal Terrestrial RAN). In NR, RAN may be called NGRAN. Also, in 6G, RAN may be called 6GRAN. In W-CDMA (UMTS), RAN may be called UTRAN.

[0090] An LTE base station 20 may be referred to as eNodeB (Evolved Node B) or eNB. In this case, EUTRAN includes one or more eNodeBs (eNBs). An NR base station 20 may be referred to as gNodeB or gNB. In this case, NGRAN includes one or more gNBs. A 6G base station may be referred to as 6GNodeB, 6gNodeB, 6GNB, or 6gNB. In this case, 6GRAN includes one or more 6GNBs. EUTRAN may also include gNBs (en-gNBs) connected to the core network (EPC) in an LTE communication system (EPS). NGRAN may also include ng-eNBs connected to the core network 5GC in a 5G communication system (5GS).

[0091] If base station 20 is an eNB, gNB, 6GNB, etc., base station 20 may be referred to as 3GPP Access. If base station 20 is an Access Point, base station 20 may be referred to as Non-3GPP Access. Base station 20 may also be an optical extension device called RRH (Remote Radio Head). If base station 20 is a gNB, base station 20 may be a combination of gNB-CU and gNB-DU described later, or it may be either gNB-CU or gNB-DU.

[0092] Here, the gNB-CU hosts multiple upper layers of the Access Stratum (e.g., RRC (Radio Resource Control), SDAP (Service Data Adaptation Protocol), PDCP (Packet Data Convergence Protocol)) for communication with the UE. On the other hand, the gNB-DU hosts multiple lower layers of the Access Stratum (e.g., RLC (Radio Link Control), MAC (Medium Access Control), PHY (Physical layer)). That is, among the messages / information described later, RRC signaling (quasi-static notifications) may be generated by the gNB-CU, while MAC CE and DCI (dynamic notifications) may be generated by the gNB-DU. Alternatively, among the RRC configuration (quasi-static notifications), some configurations, 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 or received via the F1 interface.

[0093] Base station 20 may be configured to communicate with other base stations. If multiple base stations 20 are eNBs or a combination of eNB and en-gNB, these base stations 20 may be connected by an X2 interface. If multiple base stations 20 are gNBs or a combination of ng-eNB and gNB, these base stations 20 may be connected by an Xn interface. If multiple base stations 20 are a combination of gNB-CU and gNB-DU, these base stations 20 may be connected by an F1 interface. Messages / information described later (e.g., RRC signaling, MAC CE (MAC Control Element), or DCI (Downlink Control Information), etc.) may be transmitted between multiple base stations 20 via an inter-base station interface (e.g., X2 interface, Xn interface, or F1 interface, etc.).

[0094] The cells provided by the base station 20 are sometimes called Serving Cells. The concept of a Serving Cell includes PCell (Primary Cell) and SCell (Secondary Cell). When dual connectivity is provided to the terminal device 40, the PCell provided by the Master Node (MN) and zero or one or more SCells are sometimes called a Master Cell Group. Dual connectivity may be at least one of EUTRA-EUTRA Dual Connectivity, EUTRA-NR Dual Connectivity (ENDC), EUTRA-NR Dual Connectivity with 5GC, NR-EUTRA Dual Connectivity (NEDC), NR-NR Dual Connectivity, NR-6G Dual Connectivity, and 6G-NR Dual Connectivity. Of course, dual connectivity is not limited to these.

[0095] A serving cell may include a PSCell (Primary Secondary Cell, or Primary SCG Cell). When dual connectivity is provided to the terminal device 40, the PSCell provided by the SN (Secondary Node) and zero or one or more SCells may be called an SCG (Secondary Cell Group). Unless special settings are made (e.g., PUCCH on SCell), the physical uplink control channel (PUCCH) is transmitted by PCell and PSCell, but not by SCell. Radio link failure is detected by PCell and PSCell, but not by SCell (and does not need to be detected). Because PCell and PSCell play special roles within the serving cell, they are also called SpCell (Special Cell).

[0096] A single cell may be associated with one downlink component carrier and one uplink component carrier. The system bandwidth corresponding to a single cell may be divided into multiple Bandwidth Parts (BWPs). In this case, one or more BWPs may be configured in the terminal device 40, and one BWP may be used by the terminal device 40 as an active BWP. The radio resources available to the terminal device 40, such as frequency band, numerology (subcarrier spacing), or slot configuration, may differ for each cell, each component carrier, or each BWP.

[0097] <2-3. Example of Relay Station Configuration> Next, an example of the configuration of relay station 30 will be explained.

[0098] The relay station 30 is a wireless communication device that acts as a repeater for the base station 20. The relay station 30 is a type of base station (for example, the base station 20 described above). The relay station 30 is also a type of information processing device. The relay station 30 can also be called a relay base station. The relay station 30 may also be a device called a repeater (for example, an RF Repeater, Smart Repeater, or Intelligent Surface). The relay station 30 is a wireless communication device that communicates wirelessly with other wireless communication devices (for example, the base station 20, the terminal device 40, or other relay stations 30).

[0099] The relay station 30 may be capable of NOMA communication with the terminal device 40. The relay station 30 relays communication between the base station 20 and the terminal device 40. The relay station 30 may be capable of wireless communication with other relay stations 30 and base station 20. The relay station 30 may be a ground station or a non-ground station. The relay station 30, together with the base station 20, constitutes a wireless access network RAN.

[0100] The relay station 30 may be a fixed device, a movable device, or a floating device. The coverage size of the relay station 30 is not limited to a specific size. The cells covered by the relay station 30 may be macrocells or small cells.

[0101] The device on which the relay station 30 is installed is not limited to a specific device, as long as the relay function is fulfilled. The relay station 30 may be installed in terminal devices such as smartphones, in automobiles, trains, or rickshaws, in balloons, airplanes, or drones, or in home appliances such as televisions, game consoles, air conditioners, refrigerators, or lighting fixtures. Furthermore, any device with a relay function may be considered as the relay station 30 itself.

[0102] The configuration of the relay station 30 may be the same as that of the base station 20 described above. The relay station 30 may be a device installed on a mobile device, or it may be the mobile device itself, similar to the base station 20 described above. The mobile device may be a mobile terminal such as a smartphone or mobile phone, as described above. The mobile device may be a mobile device that moves on land (ground in the narrow sense), or a mobile device that moves underground. The mobile device may be a mobile device that moves on water, or a mobile device that moves underwater. The mobile device may be a mobile device that moves within the atmosphere, or a mobile device that moves outside the atmosphere. The relay station 30 may be a ground station device, or a non-ground station device. The relay station 30 may be an aircraft station, a satellite station, etc.

[0103] The coverage size of the relay station 30 may range from large, like a macrocell, to small, like a picocell, similar to the base station 20. The coverage size of the relay station 30 may also be extremely small, like a femtocell. The relay station 30 may have beamforming capabilities. In this case, the relay station 30 may form cells or service areas for each beam. The relay station 30 may also have point forming capabilities. In this case, the relay station 30 may form cells or service areas for each point.

[0104] Figure 5 shows the configuration of the relay station 30 according to this embodiment. The relay station 30 comprises a wireless communication unit 31, a storage unit 32, and a control unit 33. However, the configuration shown in Figure 5 is a functional configuration, and the hardware configuration may differ. Furthermore, the functions of the relay station 30 may be distributed and implemented across multiple physically separated configurations.

[0105] It should be noted that the relay station 30 does not necessarily have all of the above-mentioned or later-described configurations. Furthermore, the relay station 30 may have configurations other than those described above or later.

[0106] The wireless communication unit 31 is a signal processing unit for wireless communication with other wireless communication devices (for example, at least one of the base station 20, terminal device 40, and other relay station 30). The wireless communication unit 31 may be called a wireless transceiver or simply a transceiver. In this case, the wireless communication unit 31 may be a transceiver conforming to the specifications defined in the 3GPP technical specifications (hereinafter referred to as a 3GPP transceiver). The 3GPP transceiver may be a 3G transceiver, a 4G (LTE) transceiver, a 5G (NR) transceiver, or a 5G or later generation transceiver (for example, 6G). The wireless communication unit 31 is controlled by the control unit 33. The wireless communication unit 31 supports one or more wireless access schemes. The wireless communication unit 31 may support at least one of NR, LTE, B5G, and 6G. The wireless communication unit 31 may support W-CDMA and cdma2000, in addition to NR, LTE, B5G, and 6G. The wireless communication unit 31 may also support automatic retransmission technologies such as HARQ. Some or all of the processing performed by the wireless communication unit 31 may be performed by the control unit 33.

[0107] The wireless communication unit 31 comprises a transmission processing unit 311, a reception processing unit 312, and an antenna 313. At least one of the transmission processing unit 311, the reception processing unit 312, and the antenna 313 may be considered as the wireless communication unit 31. The wireless communication unit 31 may include multiple transmission processing units 311, reception processing units 312, and antennas 313. If the wireless communication unit 31 supports multiple wireless access methods, each part of the wireless communication unit 31 may be configured separately for each wireless access method. The transmission processing unit 311 and the reception processing unit 312 may be configured separately for LTE, NR, B5G, and 6G. The antenna 313 may be composed of multiple antenna elements, for example, multiple patch antennas. The wireless communication unit 31 may have a beamforming function. For example, the wireless communication unit 31 may have a polarization beamforming function that uses vertical polarization (V polarization) and horizontal polarization (H polarization) (or a polarization beamforming function that uses dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical). The wireless communication unit 31 may also transmit the sensing signals described above or below.

[0108] The transmission processing unit 311 performs the transmission processing of 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 an encoding method such as block coding, convolutional coding, or turbo coding. Here, the encoding may be done using polar coding or LDPC coding. The transmission processing unit 311 then modulates the encoded bits using a predetermined modulation method (for example, BPSK, QPSK, 16QAM, 64QAM, 256QAM, or a higher-order multi-level modulation method). In this case, the signal points on the constellation do not necessarily have to be equidistant. The constellation may also be a non-uniform constellation. The transmission processing unit 311 then multiplexes the modulation symbols and downlink reference signals for each channel and places them in predetermined resource elements. The transmission processing unit 311 then performs various signal processing on the multiplexed signals. For example, the transmission processing unit 311 performs processing such as conversion to the frequency domain using the Fast Fourier Transform, addition of a guard interval (cyclic prefix), generation of a baseband digital signal, conversion to an analog signal, quadrature modulation, upconversion, removal of extraneous frequency components, and power amplification. The signal generated by the transmission processing unit 311 is transmitted from the antenna 313.

[0109] The receiving processing unit 312 processes the uplink signal received via the antenna 313. For example, the receiving processing unit 312 performs down-conversion, removal of unwanted frequency components, control of amplification level, quadrature demodulation, conversion to a digital signal, removal of guard intervals (cyclic prefixes), and extraction of frequency domain signals using fast Fourier transform on the uplink signal. Then, the receiving processing unit 312 separates the uplink channel and uplink reference signals, such as PUSCH and PUCCH, from the processed signal. The receiving processing unit 312 also demodulates the received signal using a modulation scheme such as BPSK or QPSK for the modulation symbols of the uplink channel. The modulation scheme used for demodulation may be 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 receiving processing unit 312 then performs decoding on the encoded bits of the demodulated uplink channel. The decoded uplink data and uplink control information are output to the control unit 33.

[0110] Antenna 313 is an antenna device that converts electric current and radio waves to each other. Antenna 313 may consist of one antenna element, for example, one patch antenna. Antenna 313 may consist of multiple antenna elements, for example, multiple patch antennas. If antenna 313 consists of multiple antenna elements, the wireless communication unit 31 may have a beamforming function. The wireless communication unit 31 may be configured to generate a directional beam by controlling the directivity of the radio signal using multiple antenna elements. Antenna 313 may be a dual-polarization antenna. If antenna 313 is a dual-polarization antenna, the wireless communication unit 31 may use vertical polarization (V polarization) and horizontal polarization (H polarization) (or dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical) when transmitting a radio signal. The wireless communication unit 31 may control the directivity of the transmitted radio signal using vertical polarization and horizontal polarization (or dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical). Furthermore, the wireless communication unit 31 may transmit and receive signals spatially multiplexed through multiple layers composed of multiple antenna elements.

[0111] The memory unit 32 is a read / write storage device such as DRAM, SRAM, flash memory, or a hard disk.

[0112] The control unit 33 is a controller that controls various parts of the relay station 30. The control unit 33 controls the wireless communication unit 31 to perform wireless communication with other wireless communication devices (for example, a base station 20, a terminal device 40, or another relay station 30). The control unit 33 may be implemented by a processor such as a CPU or MPU. Specifically, the control unit 33 may be implemented by the processor executing various programs stored in the internal memory device of the relay station 30 using RAM or the like as a working area. The control unit 33 may be implemented by an integrated circuit such as an ASIC or FPGA. Furthermore, the control unit 33 may be implemented by a GPU. CPU, MPU, ASIC, FPGA, and GPU can all be considered as controllers. The control unit 33 may be composed of multiple physically separated objects. For example, the control unit 33 may be composed of multiple semiconductor chips.

[0113] The control unit 33 comprises at least one block, which consists of a transmission control unit 331 and a reception control unit 332. The control unit 33 may comprise multiple blocks of each type, or it may comprise only one of each type.

[0114] Each block constituting the control unit 33 (transmission control unit 331 to reception control unit 332) is a functional block that represents the function of the control unit 33. These functional blocks may be software blocks or hardware blocks. For example, each of the above-mentioned functional blocks may be a single software module implemented in software (including microprograms), or a single circuit block on a semiconductor chip (die). Of course, each functional block may also be a single processor or a single integrated circuit. The control unit 33 may be composed of functional units different from the above-mentioned functional blocks. The configuration method of the functional blocks is arbitrary. The operation of the control unit 33 may be the same as the operation of the control unit (control unit 13, control unit 23, or control unit 43) of the management device 10, base station 20, or terminal device 40.

[0115] The relay station 30 may also be an IAB relay node. The relay station 30 operates as an IAB-MT (Mobile Termination) for the IAB donor node that provides backhaul, and as an IAB-DU (Distributed Unit) for the terminal device 40 that provides access. The IAB donor node may be, for example, a base station 20. In this case, the IAB donor node may operate as an IAB-CU (Central Unit).

[0116] <2-4. Example of Terminal Device Configuration> Next, an example of the configuration of the terminal device 40 will be explained.

[0117] Terminal device 40 is a wireless communication device that performs wireless communication with other wireless communication devices (for example, base station 20, relay station 30, or other terminal device 40). In the following description, terminal device 40 may be referred to as UE (User Equipment) or UE40.

[0118] The terminal device 40 can be any form of information processing device (computer). For example, the terminal device 40 may be a mobile terminal such as a mobile phone, smart device (smartphone or tablet), PDA (Personal Digital Assistant), or notebook PC. Alternatively, the terminal device 40 may be a communication module connected to an information processing device (for example, an imaging device without wireless communication capabilities) and providing wireless communication capabilities to the information processing device. Alternatively, the terminal device 40 may be an imaging device equipped with wireless communication capabilities (for example, a camcorder).

[0119] Furthermore, the terminal device 40 may be a motorcycle or mobile relay vehicle equipped with communication equipment such as an FPU (Field Pickup Unit). The terminal device 40 may also be an M2M (Machine to Machine) device or an IoT (Internet of Things) device. Additionally, the terminal device 40 may be a wearable device such as a smartwatch.

[0120] Furthermore, the terminal device 40 may be an XR (Extended Reality) device such as an AR (Augmented Reality) device, a VR (Virtual Reality) device, or an MR (Mixed Reality) device. In this case, the XR device may be a glasses-type device such as AR glasses or MR glasses, or a head-mounted device such as a VR head-mounted display. When the terminal device 40 is an XR device, the terminal device 40 may be a standalone device consisting only of a user-worn portion (e.g., a glasses portion). Alternatively, the terminal device 40 may be a terminal-linked device consisting of a user-worn portion (e.g., a glasses portion) and a terminal portion (e.g., a smart device) that is linked to that portion.

[0121] Terminal device 40 may be capable of NOMA communication with other wireless communication devices (e.g., base station 20, relay station 30, or other terminal device 40). Terminal device 40 may use automatic retransmission technology such as HARQ when communicating with other wireless communication devices. Terminal device 40 may be capable of sidelink communication with other terminal devices 40. Terminal device 40 may use automatic retransmission technology such as HARQ when performing sidelink communication. Terminal device 40 may be capable of NOMA communication when performing sidelink communication with other terminal devices 40. Terminal device 40 may be capable of LPWA communication with other wireless communication devices. The wireless communication used by terminal device 40 may be wireless communication using millimeter waves. The wireless communication used by terminal device 40, including sidelink communication, may be wireless communication using radio waves, or wireless communication using infrared or visible light, i.e., optical wireless communication.

[0122] The terminal device 40 may be a mobile wireless communication device, i.e., a mobile device. The terminal device 40 may be a wireless communication device installed on a mobile device, or it may be the mobile device itself. The terminal device 40 may be a vehicle that moves on roads, such as an automobile, bus, truck, or motorcycle, or a train that runs on tracks, or it may be a wireless communication device mounted on such a vehicle. The mobile device may be a mobile terminal, or it may be a mobile device that moves on land (ground in the narrow sense), underground, on water, or underwater. Furthermore, the mobile device may be a mobile device that moves within the atmosphere, such as an aircraft, airship, balloon, or helicopter, or it may be a mobile device that moves outside the atmosphere, such as an artificial satellite. The mobile device may be a UAV (Unmanned Aerial Vehicle) such as a drone. Also, the terminal device 40 may be a wireless communication device mounted on a mobile device.

[0123] The terminal device 40 may be capable of communicating with multiple base stations 20 or multiple cells simultaneously. If one base station 20 supports a communication area via multiple cells (for example, pCell or sCell), communication between the base station 20 and the terminal device 40 can be achieved by bundling these multiple cells together using technologies such as carrier aggregation (CA), dual connectivity (DC), or multi-connectivity (MC). Alternatively, communication between the terminal device 40 and multiple base stations 20 can be achieved via cells of different base stations 20 using coordinated multi-point transmission and reception (CoMP) technology.

[0124] The terminal device 40 may be able to communicate with a plurality of base stations 20 or a plurality of cells. The terminal device 40 may also transmit and / or receive sensing signals to and from each of the plurality of base stations 20. The terminal device 40 may be configured to receive information about sensing signals (e.g., information about resources) from at least one of the plurality of base stations 20, or to receive information about sensing signals (e.g., information about resources) from each of the plurality of base stations 20. The terminal device 40 may also transmit and / or receive sensing signals in each of the plurality of cells. The terminal device 40 may be configured to receive information about sensing signals (e.g., information about resources) from at least one of the plurality of cells, or to receive information about sensing signals (e.g., information about resources) in each of the plurality of cells.

[0125] The terminal device 40 may also be a relay terminal that relays communication to a remote terminal.

[0126] Multistatic sensing may be performed at the base station 20, the remote terminal, and the relay terminal. Specifically, sensing signals may be transmitted from both the base station 20 and the relay terminal. The remote terminal may receive sensing signals transmitted from both the base station 20 and the relay terminal.

[0127] The base station 20 and / or relay terminal may transmit to the relay terminal and / or remote terminal information regarding sensing signals transmitted and / or received by the relay terminal and / or remote terminal. In other words, the relay terminal and / or remote terminal may receive from the base station 20 and / or relay terminal information regarding sensing signals transmitted and / or received by the relay terminal and / or remote terminal.

[0128] Figure 6 shows the configuration of the terminal device 40 according to this embodiment. The terminal device 40 comprises a wireless communication unit 41, a storage unit 42, and a control unit 43. The configuration shown in Figure 6 is a functional configuration, and the hardware configuration may differ. Furthermore, the functions of the terminal device 40 may be distributed and implemented across multiple physically separated configurations.

[0129] Note that the terminal device 40 does not necessarily have all of the above-described or later-described configurations. Furthermore, the terminal device 40 may have configurations other than those described or later-described. The terminal device 40 may have a beamforming function. Furthermore, the terminal device 40 may be configured to acquire sensing data by performing sensing using a beam.

[0130] The wireless communication unit 41 is a signal processing unit for wireless communication with other wireless communication devices (for example, a base station 20, a relay station 30, or other terminal devices 40). The wireless communication unit 41 may be called a wireless transceiver or simply a transceiver. In this case, the wireless communication unit 41 may be a transceiver conforming to the standards specified in the 3GPP technical specifications (hereinafter referred to as a 3GPP transceiver). The 3GPP transceiver may be a 3G transceiver, a 4G (LTE) transceiver, a 5G (NR) transceiver, or a transceiver of a 5G or later generation. The wireless communication unit 41 is controlled, for example, by a control unit 43. The wireless communication unit 41 supports one or more wireless access schemes. The wireless communication unit 41 may support at least one of NR, LTE, B5G, and 6G. The wireless communication unit 41 may support W-CDMA and cdma2000, in addition to NR, LTE, B5G, and 6G. The wireless communication unit 41 may also support automatic retransmission technologies such as HARQ. Some or all of the processing performed by the wireless communication unit 41 may be performed by the control unit 43.

[0131] The wireless communication unit 41 comprises a transmission processing unit 411, a reception processing unit 412, and an antenna 413. At least one of the transmission processing unit 411, the reception processing unit 412, and the antenna 413 may be considered as the wireless communication unit 41. The wireless communication unit 41 may include multiple transmission processing units 411, reception processing units 412, and antennas 413. If the wireless communication unit 41 supports multiple wireless access methods, each part of the wireless communication unit 41 may be configured separately for each wireless access method. The transmission processing unit 411 and the reception processing unit 412 may be configured separately for LTE, NR, B5G, and 6G. The antenna 413 may be composed of multiple antenna elements, for example, multiple patch antennas. The wireless communication unit 41 may have a beamforming function. For example, the wireless communication unit 41 may have a polarization beamforming function that uses vertical polarization (V polarization) and horizontal polarization (H polarization) (or a polarization beamforming function that uses dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical). The wireless communication unit 41 may also transmit the sensing signals described above or below.

[0132] The memory unit 42 is a read / write storage device such as DRAM, SRAM, flash memory, or a hard disk.

[0133] The control unit 43 is a controller that controls each part of the terminal device 40. The control unit 43 controls the wireless communication unit 41 to perform wireless communication with other wireless communication devices (for example, a base station 20, a relay station 30, or another terminal device 40). The control unit 43 may be implemented by a processor such as a CPU or MPU. More specifically, the control unit 43 may be implemented by the processor executing various programs stored in the internal storage device of the terminal device 40 using RAM or the like as a working area. The control unit 43 may be implemented by an integrated circuit such as an ASIC or FPGA. CPU, MPU, ASIC, and FPGA can all be considered as controllers. The control unit 43 may be implemented by a GPU. CPU, MPU, ASIC, FPGA, and GPU can all be considered as controllers. The control unit 43 may be composed of multiple physically separated objects. For example, the control unit 43 may be composed of multiple semiconductor chips.

[0134] The control unit 43 comprises at least one block of a transmission control unit 431 and a reception control unit 432. The control unit 43 may comprise multiple blocks of each type, or it may comprise only one of each type.

[0135] Each block constituting the control unit 43 (transmit control unit 431 to receive control unit 432) is a functional block that represents the function of the control unit 43. These functional blocks may be software blocks or hardware blocks. For example, each of the above-mentioned functional blocks may be a single software module implemented in software (including microprograms), or a single circuit block on a semiconductor chip (die). Of course, each functional block may also be a single processor or a single integrated circuit. The control unit 43 may be composed of functional units different from the above-mentioned functional blocks. The configuration method of the functional blocks is arbitrary. The operation of the control unit 43 may be the same as the operation of the control units (control unit 13, control unit 23, or control unit 33) of the management device 10, base station 20, or relay station 30.

[0136] <<3. Communication Points>> The configuration of the communication system 1 has been described above. Before describing the operation of the communication system 1 of this embodiment in detail, we will now explain the communication points.

[0137] In conventional communication systems, communication control (e.g., initial access control and / or mobility control) was performed on a cell-by-cell basis. However, as mentioned above, in addition to the increasing complexity of communication topologies, it is anticipated that high-frequency bands such as millimeter waves or terahertz waves will be utilized. Therefore, future communication systems will require a higher density of communication control units. In this embodiment, this unit of communication control is called a communication point, rather than a cell.

[0138] In this embodiment, a cell-free communication system is assumed as an example of a communication system that uses communication points. However, the point of this embodiment is not a change in the definition of a cell. The method of this embodiment can be applied to communication systems in which the definition of a cell remains the same as before. In other words, a cell-free communication system is one type of communication system to which the method of this embodiment can be applied, but the method of this embodiment can also be applied to communication systems other than cell-free communication systems. For example, the method of this embodiment can be applied to a distributed MIMO system, a distributed antenna system, a multi-TRP (Transmission and Reception Point) system, or a multi-AP (Access Point) system.

[0139] <3-1. Definition of a Communication Point> A communication point is, for example, a wireless resource used when a communication service is provided. A communication point may also be referred to as a communication node or node.

[0140] The communication point may be a conventional cell (a conventional planar cell formed by the base station 20 / relay station 30; hereinafter referred to as a classic cell). However, the communication point is not limited to a cell; for example, it may be a beam in beamforming (hereinafter also referred to as a beam cell) or a point in point forming (hereinafter also referred to as a point cell). Point forming will be described later.

[0141] In addition, communication points may be radio resources divided spatially, temporally, or frequency-wise. Multiple radio resources may be multiplexed spatially, temporally, or frequency-wise to form a communication point. A wireless communication device (for example, at least one of a base station 20, a relay station 30, and a terminal device 40) can identify each communication point by some means.

[0142] The communication point in this embodiment may be any of the following (A1) to (A15). The description of "communication point" in this embodiment can be replaced with a description indicating any of the following (A1) to (A15).

[0143] (A1) Cell (classic cell) (A2) Base station (e.g., gNB) (A3) Relay station (A4) TRP (Transmission and Reception Point) (A5) Antenna (A6) Antenna element (A7) Antenna port (A8) Set of antenna ports (A9) IAB (Integrated Access and Backhaul) node (A10) Relay UE (User Equipment) (A11) Beam in beamforming (beam cell) (A12) Point in point forming (point cell) (A13) CU (Central Unit) (A14) DU (Distributed Unit) (A15) RU (Radio Unit)

[0144] Furthermore, the communication point in this embodiment may be a cluster composed of multiple elements selected from (A1) to (A15) described above. The term "communication point" in this embodiment can be replaced with a term indicating this cluster.

[0145] Furthermore, the communication point in this embodiment may also be defined as (B1) to (B2) below, in addition to or instead of the above.

[0146] (B1) A node that transmits a synchronization signal and / or broadcast control information. For example, a communication point may be a unit (node) that the terminal device 40 can recognize as the source of the first signal and / or the first broadcast information (e.g., SSB / SIB1) described later. Alternatively, for example, a communication point may be a unit (node) that the terminal device 40 can recognize as the source of the second signal and / or the second broadcast information (e.g., SSB / SIB1) described later. The terminal device 40 may recognize the communication point that transmits the first signal and / or the first broadcast information and the communication point that transmits the second signal and / or the second broadcast information as different communication points.

[0147] (B2) A unit defined based on QCL (Quasi-co-location). For example, a set of antenna ports that share the same QCL may be recognized as a single communication point (cluster).

[0148] Furthermore, the communication point in this embodiment does not need to be fixed and may be a mobile node. Moreover, the communication point in this embodiment does not need to be a terrestrial node and may be a non-terrestrial node. For example, the communication point in this embodiment may be a satellite, a drone, or an Unmanned Aerial Vehicle (UAV).

[0149] As described above, the base station 20 can be defined as a communication point. However, in this embodiment, the base station 20 does not necessarily have to be a communication point. For example, the base station 20 (or the functions of the base station 20 in this embodiment) may be a communication node capable of controlling the communication points connected to the base station 20. For example, the base station 20 in this embodiment may be a node on the core network CN side of the communication points.

[0150] Furthermore, the base station 20 can be implemented in various forms from a device perspective. For example, the base station 20 may be included in multiple communication points. The base station 20 may also control other communication points. Alternatively, for example, the base station 20 may be independent as a communication node between the core network CN and the communication points. Alternatively, for example, the base station 20 may be included in the core network CN.

[0151] <3-2. Specific Examples of Communication Systems> Next, specific examples of communication systems that use communication points will be described. As mentioned above, in this embodiment, a self-free communication system is assumed as an example of a communication system that uses communication points, but the communication system 1 of this embodiment is not limited to a self-free communication system.

[0152] Figure 7 shows an example of the communication system 1 of this embodiment. The communication system 1 of this embodiment is a wireless communication system comprising a plurality of communication devices (for example, one or more terminal devices 40 and one or more base stations 20). In the following description, the base station 20 may be referred to as BS. Also, in the following description, the terminal device 40 may be referred to as UE.

[0153] The base station 20 includes one or more communication points P (for example, one or more communication antennas). Alternatively, the base station 20 is connected by wire or wireless to one or more communication points P (for example, one or more other base stations 20 and / or one or more relay stations 30). Note that the communication points P may be part of the configuration of the base station 20. For example, one or more communication points P may be one or more antennas of the base station 20.

[0154] In the example in Figure 7, base station 20 １ (BS shown in Figure 7) １ ) is communication point P １１ ~Communication points P １Ｎ It is connected to base station 20. １ (BS shown in Figure 7) １ ) is communication point P １１ ~Communication points P １Ｎ It is equipped with, where N is any integer. Also, in the example in Figure 7, base station 20 ２ (BS shown in Figure 7) ２ ) is communication point P ２１ ~Communication points P ２Ｍ It is connected to base station 20. ２ (BS shown in Figure 7) ２ ) is communication point P ２１ ~Communication points P ２Ｍ It includes the following, where M is any integer.

[0155] Each communication point may be controlled by the connected base station 20. For example, communication point P １１ ~Communication points P １Ｎ is base station 20 １ It may be controlled by the communication point P. ２１ ~Communication points P ２Ｍ is base station 20 ２ It may be controlled by [something].

[0156] The terminal device 40 (UE shown in Figure 7) is wirelessly connected to one or more communication points P.

[0157] <3-3. Point Forming> As mentioned above, a communication point may also be a point in point forming. Point forming is a technique that concentrates power at a specific point by utilizing the phase difference of the near field. The following explains the power concentration technique at a specific point (point forming).

[0158] Figure 8 is a diagram illustrating power concentration technology (point forming) at a specific point. In conventional cellular mobile communication, a base station 20 (e.g., eNB (eNodeB), gNB (gNodeB), or RAN node (including EUTRAN, NGRAN)) concentrates power in a planar or beam-like manner to form a communication area (including femtocells, small cells, and large cells). In the example in Figure 8, the left diagram (classic cell) shows how the base station 20 forms a planar cell. The center diagram (beamforming) shows how the base station 20 forms a beam-shaped cell. As a result, the base station 20 provides communication to terminal equipment 40 (e.g., UE (User Equipment)). Next-generation cellular / cell-free communications require maximizing the efficiency of radio resource utilization (e.g., at least one of frequency, space, and time) to meet even more advanced demands (e.g., greater mass multi-connection (mMTC) and / or highly reliable, low-latency communication (URLLC)).

[0159] In beamforming, communication equipment increases power in a specific direction by coordinating the control of multiple antennas. Currently, the next technology after beamforming is attracting attention: a technology that forms cells at a point (a power concentration technology at a specific point). This is a technology that concentrates power at a single point in three dimensions, exceeding the spatial separation achieved by conventional beamforming, by coordinating the control of multiple transmitting devices (transmitting antennas, or devices with one or more transmitting antennas). In the example in Figure 8, the diagram on the right (point forming) shows how the base station 20 forms a point-shaped cell (hereinafter also called a point cell). Hereafter, this technology will be referred to as point forming, but the terminology is not limited to this. For example, point forming may also be called beamfocusing or beamfocal.

[0160] Conventional beamforming methods could not multiplex beam directions, but point forming enables three-dimensional multiplexing. This allows for simultaneous communication with even more terminals. Furthermore, point forming can suppress interference to multiple terminals. As a result, improved overall system communication quality, reduced disconnection rates, and even greater multi-connection communication can be expected.

[0161] Point forming is a technique that maximizes received power at a specific point by coordinating the operation of multiple transmitting antennas so that the radio waves transmitted from each antenna combine in phase at that point, taking into account the phase difference of each wave. Outside of the specific point, the radio waves transmitted from the multiple transmitting antennas are received with random phases, and the received power is suppressed by averaging. This realizes point forming, which forms a cell at the specific point. In controlling the phase difference of the radio waves transmitted from the multiple transmitting antennas, the control device may, for example, control the initial phase of each transmitting antenna or control the amplitude of each transmitting antenna.

[0162] The multiple antennas (multiple transmission points) used for point forming may be one or more transmitting panels comprising multiple transmitting antennas (antenna elements). Figure 9 shows an example of point forming with a single antenna having multiple antenna elements. When radio waves are transmitted from a single transmitting panel having multiple transmitting antenna elements, near-field characteristics may be taken into consideration.

[0163] Figure 10 is a diagram illustrating the near-field and far-field. Conventionally, it was assumed that base stations would communicate with distant terminal devices such as smartphones. Therefore, conventional studies proceeded based on the assumption of a far-field as shown on the right side of Figure 10. However, future communication is expected to utilize even larger transmission panels. Therefore, it may be possible to enable communication that takes into account the phase difference, which is a characteristic of the near-field region. Point forming may be used in this near-field region. Figure 11 is a diagram showing the Fraunhofer distance (also called the Rayleigh distance), which is the boundary between the near-field and the far-field.

[0164] Here, we have shown an example of applying point forming in the near field, but point forming is possible in any environment where phase difference can be considered. Therefore, in an environment where many distributed antennas are around the receiving point, point forming can be implemented regardless of the Fraunhofer distance. Of course, if phase difference can be considered at the power concentration point, the communication device can also perform point forming using a single antenna with many antenna elements.

[0165] Figure 12 shows an example of point forming in a distributed antenna environment. In the example in Figure 12, the base station 20 has a control unit (CU (Central Unit) in the example in Figure 12) that controls multiple antennas and controls the transmitting antenna. In the example in Figure 12, one CU controls the transmitting antenna, but it is not necessary for only one CU to control it. Multiple elements (for example, DU (Distributed Unit), RAT (Radio Access Technology), and TRP (Transmission and Reception Point)) may work together. Also, in the example in Figure 12, the CU and the transmitting antenna are optically connected, but it is not necessarily optically connected. Note that each of the multiple transmitting points (transmitting antennas) may be one base station 20. Also, one or more base stations 20 may control multiple transmitting points (transmitting antennas).

[0166] Generally, the degree of power concentration in point forming varies depending on the number of transmitting points used during power concentration. There is a positive correlation between the number of transmitting points used to form one or more receiving points and the level of detailed power control. In other words, the more transmitting points there are, the more detailed power control becomes possible.

[0167] Furthermore, wireless communication related to point forming is not limited to wireless communication that utilizes a technology (power concentration technology) that concentrates power at a specific point by utilizing the phase difference of the near field. Wireless communication related to point forming may also be near-field communication. Here, near-field communication may be communication over a distance shorter than the Fraunhofer distance, which is determined by the frequency band and the aperture length of the transmitting panel.

[0168] Furthermore, in the example described above, one base station 20 performed the point forming process. However, multiple base stations 20 may cooperate to perform the point forming process. For example, multiple base stations 20 may form a point cell by coordinating the control of their respective transmitting antennas with other base stations 20. The base stations 20 may also cooperate with the relay station 30.

[0169] <<4. Initial Access Control>> The communication points have been described above, but before describing the operation of the communication system 1 of this embodiment in detail, we will now explain the initial access control (also called the initial access procedure, initial access method, initial access processing, or initial connection processing).

[0170] <4-1. Basic Procedure> First, as a basic procedure for initial access control, an example of the procedure for connecting the terminal device 40 to the base station 20 will be explained. Note that the terms "base station 20" and / or "cell" used in the following explanation can be replaced with "communication point".

[0171] Initial access control is a process that transitions the wireless connection state of the terminal device 40 from an unconnected state to a connected state. In the following description, initial access control may be referred to as the initial access procedure or initial access process.

[0172] Here, the unconnected state refers to, for example, RRC_IDLE and / or RRC_INACTIVE. RRC_IDLE is an idle state in which the terminal device 40 is not connected to any cell, and is also called Idle mode. RRC_INACTIVE is a wireless connection state that indicates an inactive state newly defined in NR, and is also called Inactive mode. In RRC_INACTIVE, the RRC connection itself is not established between the terminal device 40 and the base station 20, but the terminal device 40 and the base station 20 may maintain the states they each hold for some UE contexts. The terminal device 40 and the base station 20 may use the UE contexts they have held to expedite the transition of the terminal device 40 back to the Connected state. Note that the unconnected state may include Lightning mode. The connected state is, for example, RRC_CONNECTED. RRC_CONNECTED is a connected state in which the terminal device 40 has established a connection with a specific cell (e.g., Primary Cell), and is also called CONNECTED mode.

[0173] Figure 13 is a sequence diagram showing an example of the initial access process. The initial access process will be explained below with reference to Figure 13.

[0174] An unconnected terminal device 40 performs a cell selection procedure (cell search). The cell selection procedure (cell search) is a procedure for the UE (User Equipment) to detect the PCI (Physical Cell ID) of the cell and obtain time and frequency synchronization. The cell search in this embodiment includes the steps of detecting the synchronization signal and decoding the PBCH (Physical Broadcast Channel). First, the base station 20 transmits an SSB (SS / PBCH block) and / or a PBCH (Physical Broadcast Channel) (step S11). The SSB is a block (signal / information / channel) consisting of a PBCH, a PSS (Primary Synchronization Signal), and a SSS (Secondary Synchronization Signal). The terminal device 40 detects the cell's synchronization signal (SS: Synchronization Signal) (step S12).

[0175] The terminal device 40 synchronizes the cell and the downlink based on the detected synchronization signal. After the downlink synchronization is established, the terminal device 40 attempts to decode the PBCH and obtains the MIB (Master Information Block), which is part of the system information (step S13).

[0176] System information is information that notifies the settings of the cell transmitting the system information. System information may be common to all terminal devices 40 belonging to the cell. System information may also be specific to the cell. System information includes, for example, information regarding access to the cell, information regarding cell selection, information regarding other RATs and other systems. System information includes MIB (Master Information Block) and SIB (System Information Block). MIB is information necessary to receive SIBs, etc., and is information of a fixed payload size notified by PBCH. MIB includes a part of the system frame number, information on the subcarrier spacing of predetermined information (e.g., SIB1, Msg.2 / Msg.4 for initial connection, paging, and broadcast SI messages), subcarrier offset information, DMRS type A location information, PDCCH settings for at least SIB1, cell barred information, in-frequency reselection information, etc. SIB is system information other than MIB and is notified by PDSCH.

[0177] System information can be classified into three categories: first system information, second system information, and third system information. The first and second system information include information related to cell access, information related to the acquisition of other system information, and information related to cell selection. The information contained in the MIB (Minimum Information Bag) constitutes the first system information. The information contained in SIB1 (Single Information Bag) constitutes the second system information (e.g., Remaining Minimum SI). The remaining system information constitutes the third system information (e.g., Other SI).

[0178] In NR, system information is also broadcast from the NR cell. The physical channel carrying the system information may be transmitted via a slot or a minislot. A minislot is defined as having fewer symbols than a slot. By transmitting the physical channel carrying the system information via a minislot, the time required for beam sweeping is reduced, thereby decreasing overhead. In the case of NR, the first system information is transmitted via the NR-PBCH, and the second system information is transmitted via a physical channel different from the NR-PBCH.

[0179] The terminal device 40 acquires second system information based on the MIB (i.e., first system information) (step S14). As described above, the second system information consists of SIB1 and SIB2.

[0180] SIB1 contains cell access restriction information and scheduling information for system information other than SIB1. If it is NR, SIB1 includes information about cell selection (e.g., cellSelectionInfo), information related to cell access (e.g., cellAccessRelatedInfo), information about connection establishment failure control (e.g., connEstFailureControl), scheduling information for system information other than SIB1 (e.g., si-SchedulingInfo), serving cell settings, etc. Serving cell settings include cell-specific parameters, such as downlink settings, uplink settings, and TDD setting information. Uplink settings include RACH settings, etc. If it is LTE, SIB1 includes cell access information, cell selection information, maximum uplink transmit power information, TDD setting information, system information period, system information mapping information, and SI (System Information) window length, etc.

[0181] Furthermore, if it is NR, SIB2 includes cell reselection information (e.g., cellReselectionInfoCommon) and cell reselection serving frequency information (e.g., cellReselectionServingFreqInfo). If it is LTE, SIB2 includes connection prohibition information, cell-common radio resource configuration information (radioResourceConfigCommon), uplink carrier information, etc. The cell-common radio resource configuration information includes cell-common PRACH (Physical Random Access Channel) and RACH (Random Access Channel) configuration information.

[0182] Furthermore, if the terminal device 40 fails to obtain the system information necessary to establish a link, the terminal device 40 determines that access to that cell is prohibited. For example, if it fails to obtain the first system information, the terminal device 40 determines that access to that cell is prohibited. In this case, the terminal device 40 terminates the initial access process.

[0183] If system information is obtained, the terminal device 40 executes a Random Access Procedure based on the first system information and / or the second system information (steps S15 to S18). The Random Access Procedure is sometimes referred to as the RACH Procedure (Random Access Channel Procedure) or the RA Procedure (RA Procedure).

[0184] The random access procedure includes the steps of sending a random access preamble (step S15), receiving a random access response (step S16), sending Message 3 (step S17), and receiving a contention resolution (step S18).

[0185] First, terminal device 40 selects a predetermined PRACH (Physical Random Access Channel) preamble and transmits it to base station 20 (step S15). Next, terminal device 40 receives a PDSCH (Physical Downlink Shared Channel) containing a random access response corresponding to the PRACH preamble (step S16). Next, terminal device 40 transmits a PUSCH containing message 3 using the resources scheduled by the random access response grant included in the random access response (step S17). Finally, terminal device 40 receives a PDSCH containing collision resolution corresponding to the PUSCH (step S18).

[0186] Message 3 includes an RRC (Radio Resource Control) message requesting an RRC connection. Conflict resolution includes an RRC message for RRC connection setup. When terminal device 40 receives the RRC message for RRC connection setup, it performs an RRC connection operation and transitions from the RRC idle state to the RRC connected state. After transitioning to the RRC connected state, terminal device 40 sends an RRC message to base station 20 indicating completion of RRC connection setup. Through this series of operations, terminal device 40 can connect with base station 20.

[0187] The random access preamble is sometimes referred to as message 1, the random access response as message 2, the collision resolution message as message 4, and the RRC connection setup completion message as message 5.

[0188] After all steps of the random access procedure are completed, the terminal device 40 can transition to a state where it is connected to the cell (connected state).

[0189] The random access procedure shown in Figure 13 is sometimes referred to as a four-step random access procedure (four-step RACH procedure). On the other hand, a random access procedure in which the terminal device 40 transmits a message 3 along with the transmission of a random access preamble, and the base station 20 transmits a random access response and contention resolution in response, is sometimes referred to as a two-step random access procedure (two-step RACH procedure).

[0190] <4-2. Random Access Procedures> Next, random access procedures will be explained in detail.

[0191] Random access procedures are performed for purposes such as "RRC connection setup" from an idle state to a connected (or inactive) state, and "state transition requests" from an inactive state to a connected state. Random access procedures are also used for "scheduling requests" to request resources for uplink data transmission, and "timing advance adjustments" to adjust uplink synchronization. In addition, random access procedures are performed in cases such as "on-demand SI requests" to request system information that has not been transmitted, "beam recovery" to restore a broken beam connection, and "handover" to switch connected cells.

[0192] "RRC connection setup" is an operation performed when the terminal device 40 connects to the base station 20 in response to traffic generation or other events. Specifically, it is an operation in which the base station 20 passes connection information (e.g., UE context) to the terminal device 40. The UE context is managed by predetermined communication device identification information (e.g., C-RNTI) instructed by the base station 20. After completing this operation, the terminal device 40 transitions from an idle state to an inactive state, or from an idle state to a connected state.

[0193] A "state transition request" is an operation in which the terminal device 40 requests a state transition from an inactive state to a connected state in response to the occurrence of traffic or other events. By transitioning to the connected state, the terminal device 40 can send and receive unicast data with the base station 20.

[0194] A "scheduling request" is an operation in which the terminal device 40 requests resources for uplink data transmission in response to traffic generation or other events. After successfully receiving this scheduling request, the base station 20 allocates PUSCH resources to the communication device. Note that scheduling requests can also be made via PUCCH.

[0195] "Timing advance adjustment" is an operation to adjust for the frame errors between the downlink and uplink caused by propagation delay. The terminal device 40 transmits PRACH (Physical Random Access Channel) at the adjusted timing in the downlink frame. This allows the base station 20 to recognize the propagation delay with the terminal device 40 and to instruct the terminal device 40 of the timing advance value in a message 2 or the like.

[0196] An "on-demand SI request" is an operation that requests the base station 20 to transmit system information when the terminal device 40 needs system information that has not been transmitted for reasons such as overhead of system information.

[0197] "Beam recovery" is an operation that requests recovery if the communication quality deteriorates after the beam has been established due to the movement of the terminal device 40 or the interruption of the communication path by other objects. Upon receiving this request, the base station 20 attempts to connect with the terminal device 40 using a different beam.

[0198] "Handover" is the operation of switching the connection from the cell to which the terminal device 40 is connected (serving cell) to an adjacent cell (neighbor cell) due to changes in the radio wave environment, such as the movement of the terminal device 40. When the terminal device 40 receives a handover command from the base station 20, it requests a connection to the neighbor cell specified by the handover command.

[0199] Random access procedures include contention-based random access procedures and non-contention-based random access procedures.

[0200] The random access procedure described below assumes that the RAT supported by communication system 1 is LTE. However, the random access procedure described below is also applicable when the RAT supported by communication system 1 is something other than LTE. For example, the random access procedure described below is also applicable when the RAT supported by communication system 1 is B5G and / or 6G.

[0201] The following describes collision-based random access procedures and non-collision-based random access procedures in detail.

[0202] <4-2-1. Collision-Based Random Access Procedure> The collision-based random access procedure is a random access procedure initiated by the terminal device 40. Figure 14 shows the collision-based random access procedure. As shown in Figure 14, the collision-based random access procedure is a four-step procedure that begins with the transmission of a random access preamble from the terminal device 40. The collision-based random access procedure includes the steps of transmitting a random access preamble (Message 1), receiving a random access response (Message 2), transmitting a message (Message 3), and receiving a conflict resolution message (Message 4).

[0203] First, the terminal device 40 randomly selects a preamble sequence to use from a predetermined set of preamble sequences. Then, the terminal device 40 sends a message containing the selected preamble sequence (Message 1: Random Access Preamble) to the connected base station 20 (step S21). The random access preamble is transmitted using PRACH.

[0204] When base station 20 receives a random access preamble, it sends a random access response (Message 2) to terminal device 40. This random access response is transmitted, for example, using a PDSCH. Terminal device 40 receives the random access response (Message 2) sent from base station 20 (step S22). The random access response includes one or more random access preambles that base station 20 received, and the UL (Uplink) resource (hereinafter referred to as the uplink grant) corresponding to the random access preamble. The random access response also includes TC-RNTI (Temporary Cell Radio Network Temporary Identifier), which is a unique identifier for terminal device 40 that base station 20 has temporarily assigned to terminal device 40.

[0205] When terminal device 40 receives a random access response from base station 20, it determines whether the received information includes the random access preamble transmitted in step S21. If the random access preamble is included, terminal device 40 extracts the uplink grant corresponding to the random access preamble transmitted in step S21 from among the uplink grants included in the random access response. Then, terminal device 40 uses the resources scheduled by the extracted uplink grant to transmit a UL message (Message 3: Scheduled Transmission) (step S23). The transmission of message (Message 3) is performed using PUSCH. Message (Message 3) includes an RRC message for RRC (Radio Resource Control) connection request. Message (Message 3) also includes the identifier of terminal device 40.

[0206] In a collision-based random access procedure, a random access preamble randomly selected by terminal device 40 is used in the procedure. Therefore, it is possible that when terminal device 40 transmits a random access preamble, another terminal device 40 may simultaneously transmit the same random access preamble to the base station 20. In this case, the base station 20 recognizes which terminal devices have a preamble conflict by receiving the identifier transmitted by terminal device 40 in step S23 and resolves the conflict. The base station 20 sends a contention resolution message (Message 4) to the terminal device 40 selected by the conflict resolution. The contention resolution message (Message 4) includes the identifier transmitted by terminal device 40 in step S23. The contention resolution message (Message 4) also includes an RRC message for RRC connection setup. Terminal device 40 receives the contention resolution message (Message 4) transmitted from the base station 20 (step S24).

[0207] The terminal device 40 compares the identifier transmitted in step S23 with the identifier received in step S24. If the identifiers do not match, the terminal device 40 restarts the random access procedure from step S21. If the identifiers match, the terminal device 40 performs an RRC connection operation and transitions from the idle state (RRC_IDLE) to the connected state (RRC_CONNECTED). The terminal device 40 uses the TC-RNTI acquired in step S22 as the C-RNTI (Cell Radio Network Temporary Identifier) ​​for subsequent communications. After transitioning to the connected state, the terminal device 40 sends an RRC message to the base station 20 indicating that the RRC connection setup is complete. This message indicating the completion of the RRC connection setup is also called message 5. Through this series of operations, the terminal device 40 connects with the base station 20.

[0208] Note that the collision-based random access procedure shown in Figure 14 is a four-step random access procedure (4-step RACH). However, the communication system 1 can also support a two-step random access procedure (2-step RACH) as a collision-based random access procedure. For example, the terminal device 40 transmits the message shown in step S23 (Message 3) along with the random access preamble. The base station 20 then transmits a random access response (Message 2) and a conflict resolution (Message 4) in response. Since the random access procedure is completed in two steps, the terminal device 40 can quickly connect to the base station 20.

[0209] Note that Message 1 may be written as "Msg1" or "Msg.1". Message 2 may be written as "Msg2" or "Msg.2". Message 3 may be written as "Msg3" or "Msg.3". Message 4 may be written as "Msg4" or "Msg.4".

[0210] <4-2-2. Non-collision-based random access procedure> The non-collision-based random access procedure is a random access procedure initiated by the base station 20. Figure 15 shows the non-collision-based random access procedure. The non-collision-based random access procedure is a three-step procedure that begins with the transmission of a random access preamble assignment from the base station 20. The non-collision-based random access procedure includes the steps of receiving a random access preamble assignment (Message 0), transmitting a random access preamble (Message 1), and receiving a random access response (Message 2).

[0211] In collision-based random access procedures, terminal device 40 randomly selects a preamble sequence. However, in non-collision-based random access procedures, base station 20 assigns a specific random access preamble to terminal device 40. Terminal device 40 receives a random access preamble assignment (Message 0: RA Preamble Assignment) from base station 20 (step S31).

[0212] The terminal device 40 performs random access to the base station 20 using the random access preamble assigned in step S31. That is, the terminal device 40 transmits the assigned random access preamble (Message 1: Random Access Preamble) to the base station 20 using PRACH (step S32).

[0213] The base station 20 receives a random access preamble (Message 1) from the terminal device 40. Then, the base station 20 sends a random access response (Message 2) to the terminal device 40 for the random access preamble (step S33). The random access response includes, for example, information about the uplink grant corresponding to the received random access preamble. When the terminal device 40 receives the random access response (Message 2), it performs an RRC connection operation and transitions from the idle state (RRC_IDLE) to the connected state (RRC_CONNECTED).

[0214] Thus, in a collision-free random access procedure, the base station 20 schedules the random access preamble, making preamble collisions less likely.

[0215] Note that Message 0 may be written as "Msg0" or "Msg.0". Message 1 may be written as "Msg1" or "Msg.1". Message 2 may be written as "Msg2" or "Msg.2".

[0216] <4-2-3. Details of the Random Access Procedure for NR> The above describes the random access procedure assuming that the RAT supported by communication system 1 is LTE. Note that the above random access procedure is also applicable to RATs other than LTE. Below, we will describe in detail the random access procedure assuming that the RAT supported by communication system 1 is NR (5G).

[0217] In the following explanation, the four steps related to Message 1 to Message 4 shown in Figure 14 or Figure 15 will be described in detail. The step for Message 1 corresponds to step S21 shown in Figure 14 or step S32 shown in Figure 15. The step for Message 2 corresponds to step S22 shown in Figure 14 or step S33 shown in Figure 15. The step for Message 3 corresponds to step S23 shown in Figure 14. The step for Message 4 corresponds to step S24 shown in Figure 14.

[0218] NR Random Access Preamble (Message 1) In NR, PRACH is called NR-PRACH (NR Physical Random Access Channel). NR-PRACH is constructed using Zadoff-Chu sequences. In NR, multiple preamble formats are defined as the format of NR-PRACH. The preamble format is defined by a combination of parameters such as the subcarrier spacing of the PRACH, transmission bandwidth, sequence length, number of symbols used for transmission, transmission repetitions, CP (Cyclic Prefix) length, and guard period length. The types of NR-PRACH preamble sequences are numbered. The number of the type of preamble sequence is called the preamble index.

[0219] In NR, settings related to NR-PRACH are configured for idle terminal devices 40 based on system information. Furthermore, settings related to NR-PRACH are configured for connected terminal devices 40 via dedicated RRC signaling.

[0220] Terminal device 40 transmits NR-PRACH using a physical resource (NR-PRACH Occasion) that can transmit NR-PRACH. The physical resource is indicated by the settings related to NR-PRACH. Terminal device 40 selects one of the physical resources and transmits NR-PRACH. Furthermore, if terminal device 40 is connected, terminal device 40 transmits NR-PRACH using an NR-PRACH resource. An NR-PRACH resource is a combination of the NR-PRACH preamble and its physical resource. Base station 20 can instruct terminal device 40 on the NR-PRACH resource.

[0221] NR-PRACH is also transmitted when the random access procedure fails. When retransmitting NR-PRACH, terminal device 40 waits for a waiting period calculated from the backoff value (backoff indicator, BI) before transmitting NR-PRACH. The backoff value may vary depending on the terminal category of terminal device 40 and the priority of the traffic that occurred. In this case, multiple backoff values ​​are notified, and terminal device 40 selects the backoff value to use according to priority. Also, when retransmitting NR-PRACH, terminal device 40 increases the transmission power of NR-PRACH compared to the initial transmission. This procedure is called power ramping.

[0222] NR Random Access Response (Message 2) NR random access responses are transmitted using the NR-PDSCH (NR Physical Downlink Shared Channel). The NR-PDSCH containing the random access response is scheduled by the NR-PDCCH (NR Physical Downlink Control Channel), which has its CRC (Cyclic Redundancy Check) scrambled by RA-RNTI. The NR-PDCCH is transmitted in the CORESET (Control Resource Set). The NR-PDCCH with its CRC scrambled by RA-RNTI is placed in the CSS (Common Search Space) of the Type1-PDCCH CSS set. The value of RA-RNTI (Random Access Radio Network Temporary Identifier) ​​is determined based on the transmission resource of the NR-PRACH corresponding to that random access response. The transmission resources for NR-PRACH are, for example, time resources (slots or subframes) and frequency resources (resource blocks). NR-PDCCH may be placed in a search space associated with an NR-PRACH linked to a random access response. Specifically, the search space where NR-PDCCH is placed is configured in association with the NR-PRACH preamble and / or the physical resource from which the NR-PRACH was transmitted. The search space where NR-PDCCH is placed is configured in association with the preamble index and / or the index of the physical resource. NR-PDCCH resides in NR-SS (NR Synchronization signal) and QCL (quasi-co-located).

[0223] The NR random access response contains MAC (Medium Access Control) information. The NR random access response includes at least the uplink grant for sending NR message 3, the timing advance value used to adjust uplink frame synchronization, and the TC-RNTI value. The NR random access response also includes the PRACH index used for the NR-PRACH transmission corresponding to that random access response. Furthermore, the NR random access response includes information about the backoff used to wait for PRACH transmission.

[0224] The base station 20 transmits a random access response in NR-PDSCH format. The terminal device 40 determines whether the transmission of the random access preamble was successful based on the information contained in the random access response. If it determines that the transmission of the random access preamble was successful, the terminal device 40 performs the transmission process of NR message 3 according to the information contained in the random access response. On the other hand, if the transmission of the random access preamble fails, the terminal device 40 determines that the random access procedure has failed and performs the retransmission process of NR-PRACH.

[0225] Furthermore, the NR's random access response may include multiple uplink grants for sending the NR's message 3. The terminal device 40 can select one resource from the multiple uplink grants to send message 3. This mitigates collisions in sending the NR's message 3 when different terminal devices 40 receive the same NR's random access response. As a result, the communication system 1 can provide a more stable random access procedure.

[0226] NR Message 3 NR Message 3 is transmitted via NR-PUSCH (NR Physical Uplink Shared Channel). NR-PUSCH is transmitted using the resources indicated by the random access response. NR Message 3 contains an RRC connection request message. The format of NR-PUSCH is indicated by parameters included in the system information. For example, the parameters determine whether to use OFDM (Orthogonal Frequency Division Multiplexing) or DFT-s-OFDM (Discrete Fourier Transform Spread OFDM) as the format for NR-PUSCH.

[0227] If NR message 3 is successfully received, base station 20 proceeds to the conflict resolution (Message 4) transmission process. On the other hand, if NR message 3 is not successfully received, base station 20 attempts to receive NR message 3 again for at least a predetermined period of time.

[0228] Another example of instructions for retransmitting message 3 and the transmission resources involved is the instruction by NR-PDCCH used for instructing the retransmission of message 3. This NR-PDCCH is an uplink grant. The DCI (Downlink Control Information) of this NR-PDCCH instructs the resources for retransmitting message 3. The terminal device 40 retransmits message 3 based on the instructions from the uplink grant.

[0229] If the NR conflict resolution is not successfully received within a predetermined period, the terminal device 40 considers the random access procedure to have failed and performs the NR-PRACH retransmission process. The transmission beam of the terminal device 40 used to retransmit the NR message 3 may be different from the transmission beam of the terminal device 40 used to initially transmit the message 3. If neither the NR conflict resolution nor the instruction to retransmit message 3 is received within the predetermined period, the terminal device 40 considers the random access procedure to have failed and performs the NR-PRACH retransmission process. This predetermined period is set, for example, by system information.

[0230] NR Conflict Resolution (Message 4) NR conflict resolution is transmitted using NR-PDSCH. NR-PDSCH containing conflict resolution is scheduled by NR-PDCCH with CRC scrambled by TC-RNTI or C-RNTI. NR-PDCCH with CRC scrambled by TC-RNTI is placed in the CSS of Type1-PDCCH CSS set. NR-PDCCH may also be placed in USS (User equipment specific Search Space). NR-PDCCH may also be placed in other CSSs.

[0231] If terminal device 40 successfully receives the NR-PDSCH including the conflict resolution, it sends an acknowledgment (ACK) to base station 20. Thereafter, terminal device 40 considers the random access procedure to have been successful and transitions to the connected state (RRC_CONNECTED). On the other hand, if base station 20 receives a negative acknowledgment (NACK) for the NR-PDSCH from terminal device 40, or if there is no response, base station 20 retransmits the NR-PDSCH including the conflict resolution. If terminal device 40 fails to receive the NR conflict resolution (Message 4) within a predetermined period, it considers the random access procedure to have failed and retransmits the random access preamble (Message 1).

[0232] <4-2-4. NR's 2-STEP RACH> Next, an example of NR's 2-STEP RACH procedure (hereinafter referred to as the 2-step random access procedure) is shown. Figure 16 is a diagram of the 2-step random access procedure. The 2-step random access procedure consists of two steps: message A (step S41) and message B (step S42). As an example, message A includes message 1 (preamble) and message 3 of the conventional 4-step random access procedure (4-STEP RACH procedure), and message B includes message 2 and message 4 of the conventional 4-step random access procedure. Also, as an example, message A consists of a preamble (also called PRACH) and PUSCH, and message B consists of PDSCH.

[0233] By using a two-step random access procedure, it becomes possible to complete the random access procedure with lower latency compared to the conventional four-step random access procedure.

[0234] The preamble and PUSCH included in message A may be configured in conjunction with their respective transmission resources, or they may be configured as independent resources.

[0235] When transmission resources are associated and configured, for example, when the transmission resource for the preamble is determined, a unique or multiple candidate transmission resource for PUSCH is determined. As an example, the time and frequency offset between the PRACH occasion preamble and the PUSCH occasion is defined by a single value. As another example, the time and frequency offset between the PRACH occasion preamble and the PUSCH occasion may be defined by different values ​​for each preamble. The offset values ​​may be determined by the specification, or the base station 20 may set them quasi-statically. As an example of the time and frequency offset values, they may be defined by a predetermined frequency. For example, in an unlicensed band (e.g., 5GHz band, band 45), the time offset value can be set to 0 or a value close to 0. This makes it possible to omit LBT (Listen Before Talk) before transmitting PUSCH.

[0236] On the other hand, if configured with independent resources, the transmission resources for the preamble and PUSCH may be determined by the specifications, the resources may be configured quasi-statically by the base station 20, or the resources may be determined from other information. Other information may include, for example, slot format information (e.g., Slot Format Indicator), BWP (Band Width Part) information, preamble transmission resource information, slot index, and resource block index. Also, if configured with independent resources, the association between the preamble and PUSCH constituting a single message A may be notified to the base station 20 by the payload of the PUSCH or the UCI contained in the PUSCH, or by the transmission physical parameters of the PUSCH (e.g., the scramble sequence of the PUSCH, the DMRS sequence and / or pattern, or the transmission antenna port of the PUSCH).

[0237] Furthermore, the method for configuring the preamble and PUSCH transmission resources may be switched between being configured as linked resources and being configured as independent resources. For example, the independent resource configuration may apply to licensed bands, while the linked resource configuration may apply to unlicensed bands.

[0238] The above describes a random access procedure assuming that the RAT supported by communication system 1 is NR. Note that the above random access procedure is also applicable to RATs other than NR (e.g., B5G and / or 6G).

[0239] <4-3. Initial Access Control in Self-Free Communication> The initial access control (initial access processing) described above is also applicable to self-free communication. The initial access control (initial access processing) in self-free communication will be explained below.

[0240] In initial access control (initial access processing), the terminal device 40 receives at least a first signal, first broadcast information, and a second signal from the communication point. Based on these signals and information, the terminal device 40 performs initial access processing. The first signal, first broadcast information, and second signal are described below. Note that the first signal, first broadcast information, and second signal described below are also applicable to communications other than self-free communication.

[0241] <4-3-1. The First Signal> First, let's explain the first signal.

[0242] The first signal may be a predetermined signal detected by the terminal device 40 before receiving the first broadcast information. Alternatively, the first signal may be a signal for the terminal device 40 to perform at least one of the following: time synchronization, frequency synchronization, cell ID recognition, recognition of the resource for the first broadcast information, and reception processing of the first broadcast information.

[0243] The first signal may be a synchronization signal having the same function, purpose, and configuration as, for example, the PSS and / or SSS in 5G. Alternatively, the first signal may be a synchronization signal having the same function, purpose, and configuration as, for example, the PSS and / or SSS in 5G. Of course, the first signal is not limited to these signals.

[0244] The first signal is transmitted from a predetermined communication point among one or more communication points. In this case, the first signal may be transmitted from multiple communication points. For example, the first signal may be transmitted from all communication points connected to a base station 20.

[0245] <4-3-2. First Information> Next, we will explain the first information.

[0246] The first broadcast information is information that enables the terminal device 40 to perform at least one of the following: perform an initial access and receive a second signal. The first broadcast information does not necessarily have to be transmitted in a single transmission unit, a single resource, or a single channel. The first broadcast information may be transmitted in multiple transmission units, multiple resources, or multiple channels.

[0247] The first broadcast information is, for example, information (or channel) with the same function, purpose, and configuration as at least one of PBCH, MIB, and SIB in 5G. Alternatively, the first broadcast information is, for example, information (or channel) with the same function, purpose, and configuration as at least one of PBCH, MIB, and SIB in 5G. Of course, the first broadcast information is not limited to this information (or channel).

[0248] (Information included in the first broadcast information) The first broadcast information may include at least one of the following: information relating to the second signal and information relating to the initial access.

[0249] (1) Information concerning the second signal Information concerning the second signal is information necessary for the terminal device 40 to receive the second signal. Information concerning the second signal may be a list of one or more second signals that the terminal device 40 may receive or should receive. In this case, the second signals included in the list may be all of the second signals transmitted / managed / controlled by the communication point that transmits the first signal and / or the first broadcast information. Alternatively, the second signals included in the list may be a part of the second signals transmitted / managed / controlled by the communication point that transmits the first signal and / or the first broadcast information. In this case, the second signals included in the list may be determined according to the location of the terminal device 40, etc.

[0250] The information relating to the second signal may include, for example, at least one of the information shown in (C1) to (C4) below.

[0251] (C1) The number of signals that the terminal device 40 may receive or should receive. (C2) Time and frequency resource information. (C3) If the second signal is code-divided multiplexed, information about the code (e.g., code index). (C4) If a scrambled code is superimposed on the second signal (e.g., if the second signal is generated based on a scrambled code), information about that scrambled code.

[0252] Furthermore, the information regarding the second signal may include a list of communication points that can be combined.

[0253] (2) Information regarding initial access Information regarding initial access may be information necessary for the terminal device 40 to perform initial access processing (initial access control) to the communication point. Here, the communication point may be a predetermined base station 20, a predetermined communication point connected to the predetermined base station 20, or a core network controlling the predetermined base station 20. The communication point may also be a communication node associated with (determined based on) the predetermined base station 20, a predetermined communication point, or a predetermined core network.

[0254] Furthermore, information regarding the initial access may be transmitted from each communication point as a second piece of information.

[0255] Information regarding initial access may include, for example, at least one of the following pieces of information: (D1) to (D3).

[0256] (D1) Information necessary for transmitting, selecting, or determining a random access channel (Msg1). For example, the information regarding initial access may include information necessary for selecting or determining a random access channel. For example, the information regarding initial access may include information indicating the selectable range of random access preambles to be transmitted on the random access channel. The information regarding initial access may also include information regarding time and frequency resources for transmitting the random access channel.

[0257] (D2) Information necessary for receiving the random access response (Msg2). For example, the information regarding the initial access may include information necessary for recognizing or detecting the random access response.

[0258] (D3) Information regarding PUSCH (Msg3) For example, the information regarding initial access may include information regarding the information to be transmitted by PUSCH. For example, the information regarding initial access may include information regarding the selected communication point and / or information regarding the communication quality for one or more communication points.

[0259] (Other) The first broadcast information is transmitted from a predetermined communication point among one or more communication points. In this case, the first broadcast information may be transmitted from multiple communication points. For example, the first broadcast information may be transmitted from all communication points connected to a base station 20.

[0260] Furthermore, the first broadcast information may be transmitted from the same communication point as the first signal. That is, the QCI (QoS Class Identifier) ​​of the first broadcast information may be recognized as being the same as the QCI of the first signal. For example, when the terminal device 40 demodulates and / or decodes the first broadcast information, it may do so using at least a part of the propagation path characteristics of the first signal.

[0261] The first notification information may be transmitted from a different communication point than the first signal.

[0262] <4-3-3. Second Signal> Next, we will explain the second signal. The second signal may be at least one of the following signals (E1) to (E4). Of course, the second signal is not limited to these signals.

[0263] (E1) Reference signal transmitted from a communication point For example, the second signal may be a reference signal transmitted from a communication point. For example, the second signal may be a known reference signal that the terminal device 40 can recognize as being transmitted from a predetermined communication point. Here, the QCI of the second signal may be different from the QCI of the first broadcast information and / or the QCI of the first signal.

[0264] (E2) A signal for measuring the communication quality of a communication point The second signal may be a signal for measuring (detecting, recognizing, or actually measuring) the communication quality of a communication point. For example, the second signal may be a known signal used in initial access control to select a communication point and / or report on the communication quality.

[0265] Here, the communication quality may be RSRP, RSRQ, RSSI, SINR, SNR, SIR, CSI, CQI, PMI, or RI.

[0266] RSRP (Reference Signal Received Power) indicates the power level of a reference signal received from a specific communication point. This value shows how strongly the receiver is receiving the reference signal. RSRP is used, for example, to evaluate the quality of communication.

[0267] RSRQ (Reference Signal Received Quality) is an index that indicates the level of noise relative to RSRP. In other words, RSRQ represents the ratio of signal strength to noise level. RSRQ is used, for example, to evaluate signal quality.

[0268] RSSI (Received Signal Strength Indicator) is a value that indicates the strength of a received signal. RSSI is used, for example, to measure the strength of a wireless communication signal. However, unlike other indicators, RSSI does not contain information about the quality of a particular signal.

[0269] SINR (Signal-to-Interference-plus-Noise Ratio) indicates the ratio of signal to interference / noise.

[0270] SNR (Signal-to-Noise Ratio) indicates the ratio of signal to noise.

[0271] SIR (Signal-to-Interference Ratio) indicates the ratio of signal to interference. SIR is used to evaluate the quality of communications.

[0272] Channel State Information (CSI) is information that indicates the state of a radio propagation path. CSI is used to understand the characteristics or quality of a communication path.

[0273] The Channel Quality Indicator (CQI) is an indicator of the quality of a radio propagation path. The CQI corresponds to the frequency utilization efficiency according to a given modulation scheme and the number of MIMO layers.

[0274] The PMI (Precoding Matrix Indicator) indicates a matrix for effectively transmitting signals between transmitting antennas in MIMO (Multiple-Input Multiple-Output) communication.

[0275] RI (Rank Indicator) indicates the number of MIMO layers in MIMO communication (e.g., rank number, number of transmitting antennas, or available spatial multiplexing).

[0276] (E3) A second signal for measuring the characteristics between communication points may be a signal for measuring (detecting, recognizing, measuring, or reporting) the relative characteristics (quality, or features) between communication points. The communication quality of each communication point may be measured using the second signal. The relative characteristics between communication points may be used to report in initial access control.

[0277] Furthermore, the relative characteristics between communication points may include differences in propagation characteristics between communication points. Differences in propagation characteristics between communication points may also be information indicating differences in propagation characteristics between communication points, or changes in propagation characteristics between communication points. Differences in propagation characteristics between communication points may include, for example, at least one of the following: Differences in received power (e.g., RSRP, path loss, or SNR) between communication points Differences in delay time (e.g., arrival time, or delay dispersion) between communication points Differences in Doppler frequency between communication points Differences in phase between communication points Differences in the above-mentioned communication quality between communication points

[0278] In determining the differences in propagation characteristics between communication points, the reference communication point may be predetermined or defined, or it may be determined by a predetermined criterion. For example, the reference communication point may be any of the following: • The communication point with the smallest or largest value associated with the communication point (e.g., communication point ID (index)) • The communication point with the largest or smallest received power • The communication point with the fastest or slowest arrival time • The communication point with the best or worst communication quality for the communication point

[0279] Furthermore, the reference communication point may be determined based on a second signal transmitted by the communication point (for example, the transmission resource for the second signal, or an ID indicating the second signal). Alternatively, the reference communication point may be set by the first broadcast information or the second broadcast information.

[0280] (E4) The second synchronization signal transmitted from the communication point may be a synchronization signal having the same function, purpose, and configuration as, for example, the PSS and / or SSS in 5G. Alternatively, the second signal may be a synchronization signal having the same function, purpose, and configuration as, for example, the PSS and / or SSS in 5G.

[0281] <<5. Operation of the Communication System>> Based on the above, the operation of communication system 1 will be explained in detail. First, some of the technologies / terminology that are prerequisites for the explanation of the operation will be explained.

[0282] (PCell and SCell) In this embodiment, PCell and SCell are not limited to cells used for dual connectivity (DC). For example, PCell and SCell may be cells used for carrier aggregation (CA), multi-connectivity (MC), or coordinated multi-point transmission and reception (CoMP). Here, PCell may be, for example, a cell (first cell) that performs initial access to the terminal device 40 in a master cell group (MCG), which is a group of cells that operate in coordination. SCell may be, for example, an auxiliary cell (second cell) that works in conjunction with PCell in the MCG to provide data expansion and / or high-quality communication.

[0283] (On-demand first signal and / or on-demand first broadcast information) In this embodiment, on-demand transmission of the first signal and / or first broadcast information means that the communication point transmits the first signal and / or first broadcast information on demand. That is, when a communication point supports on-demand transmission, the communication point does not continuously transmit the first signal and / or first broadcast information repeatedly (for example, periodically) at all times, but only transmits the first signal and / or first broadcast information repeatedly (for example, periodically) when requested. Specifically, a communication point that supports on-demand transmission is basically in a sleep or power-off state and is activated in response to a trigger signal from a communication device (for example, terminal device 40 and / or base station 20) or another communication point. The activated communication point then sets a transmission window (time window) and transmits the first signal and / or first broadcast information repeatedly (for example, periodically) during that transmission window. Alternatively, the activated communication point repeatedly (e.g., periodically) transmits the first signal and / or the first broadcast information until it goes back to sleep or is powered off again.

[0284] In the following explanation, the first signal transmitted from the communication point upon request may be referred to as the on-demand first signal, or simply the on-demand first signal. If the first signal is SSB, the on-demand SSB may be referred to as on-demand SSB, or OD-SSB. Similarly, in the following explanation, the first broadcast information transmitted from the communication point upon request may be referred to as the on-demand first broadcast information, or simply the on-demand first broadcast information. If the first broadcast information is SIB1, the on-demand SIB1 may be referred to as on-demand SIB1, or OD-SIB1. Of course, the on-demand first signal / on-demand first broadcast information is not limited to on-demand SSB / on-demand SIB1.

[0285] (Trigger signal) In this embodiment, the trigger signal is assumed to include an initial trigger signal, an extended trigger signal, and a stop trigger signal.

[0286] An initial trigger signal (hereinafter simply referred to as the initial trigger) is a signal transmitted from a communication device (e.g., terminal device 40 and / or base station 20) or another communication point in order to wake up or activate the communication point corresponding to the on-demand first signal and / or on-demand first broadcast information, or to request the transmission of the on-demand first signal and / or on-demand first broadcast information. The initial trigger may also be referred to as, for example, WUS (Wake Up Signal), UL WUS (Uplink Wake Up Signal), or excitation signal. The signal configuration and other details will be described later.

[0287] An extension trigger signal (hereinafter simply referred to as an extension trigger) is a signal transmitted from a communication device (e.g., terminal device 40 and / or base station 20) or another communication point to request an extension of the transmission of the on-demand first signal and / or the on-demand first broadcast information. The signal configuration and other details will be described later.

[0288] A stop trigger signal (hereinafter simply referred to as a stop trigger) is a signal transmitted from a communication device (e.g., terminal device 40 and / or base station 20) or another communication point to request the cessation of transmission of the on-demand first signal and / or on-demand first broadcast information. The signal configuration and other details will be described later.

[0289] (Resources) In the following explanation, resources refer to, for example, Frequency, Time, Resource Element (including REG, CCE, and CORESET), Resource Block, Bandwidth Part, Component Carrier, Symbol, Sub-Symbol, Slot, Mini-Slot, Subslot, Subframe, Frame, PRACH occasion, Occasion, Code, Multi-access physical resource, Multi-access signature, or Subcarrier Spacing (Numerology).

[0290] (Other) In the following explanations, when providing specific examples, specific values ​​are sometimes given. However, the values ​​may be different from those given in the examples.

[0291] <5-1. System Architecture> The system architecture assumed in the description of the operation of communication system 1 is described below. Note that the system architecture shown below is merely an example. The operation of communication system 1 described in this embodiment can be applied to other system architectures as well.

[0292] Figure 17 is a schematic diagram showing an example of the system architecture according to this embodiment. In the example of Figure 17, the communication system 1 is a first communication point P Ａ And the second communication point P Ｂ and the first terminal device 40 (hereinafter referred to as UE Ａ ) and the second terminal device 40 (hereinafter referred to as UE Ｂ It is said that it includes the following: ) and the first communication point P Ａ And the second communication point P Ｂ And, UE Ａ And, UE Ｂ These may each be communication nodes that constitute a self-free communication system (self-free communication network).

[0293] Note that the system architecture shown in Figure 17 is merely an example. The system architecture of this embodiment is not limited to the example shown in Figure 17. The configuration and function of each element will be described below.

[0294] <5-1-1. First Communication Point> First Communication Point P Ａ In its initial state, UE Ａ This is a communication point to which it is connected. In the example in Figure 17, UE Ａ The first communication point P Ａ They are camping at the first communication point P. Ａ In its initial state, UE Ｂ It may be connected to UE. Ｂ The first communication point P Ａ You can camp there.

[0295] First communication point P Ａ This may be the first cell (PCell) of an MCG that performs coordinated communication between communication points. Coordinated communication between communication points may be by CA, DC, MC, or CoMP. The first communication point P Ａ This is the second communication point P Ｂ For example, they may be connected by backhaul and / or IAB (Integrated Access and Backhaul).

[0296] Also, the first communication point P Ａ This is the second communication point P Ｂ To trigger the transmission of the on-demand first signal and / or on-demand first broadcast information, an initial trigger is set at the second communication point P. Ｂ It may also be transmitted to the first communication point P. Ａ UE Ａ From there, the second communication point P Ｂ An initial trigger may be received for the first communication point P. Ａ UE Ａ When an initial trigger is received from the second communication point P Ｂ An initial trigger may be sent to the first communication point P.Ａ may instruct the UE to transmit an initial trigger. Also, the first communication point P Ａ may notify the second communication point P Ａ of the resources for receiving the initial trigger. For example, the first communication point P Ｂ may notify the time resources if it is TDD (Time Division Duplex), the frequency resources if it is FDD (Frequency Division Duplex), and the time and frequency resources if it is FD (Full Duplex / Flexible Duplex) to the second communication point P Ａ . Also, the first communication point P Ａ may notify the second communication point P Ｂ of the signal configuration of the initial trigger. These notifications may be made using at least one of, for example, RRC (Radio Resource Control) signaling, MAC-CE (Medium Access Control-Control Element), PBCH, SIB, SIB1, and DCI (Downlink Control Information).

[0297] Also, the first communication point P Ａ may transmit an extension trigger to the second communication point P Ｂ to extend the transmission of the on-demand first signal and / or the on-demand first notification information by the second communication point P Ｂ . Also, the first communication point P Ａ may receive an extension trigger from the UE Ａ for the second communication point P Ｂ . And when the first communication point P Ａ receives an extension trigger from the UE Ａ , it may transmit an extension trigger to the second communication point P Ｂ . Also, the first communication point P Ａ may instruct the UE Ａ to transmit an extension trigger. Also, the first communication point P Ａ is the second communication point PＢ It may notify resources for receiving an extension trigger. For example, the first communication point P Ａ may notify time resources if it is TDD (Time Division Duplex), frequency resources if it is FDD (Frequency Division Duplex), and time and frequency resources if it is FD (Full Duplex / Flexible Duplex). Also, the first communication point P Ａ may notify the second communication point P Ｂ of the signal configuration of the extension trigger. For example, the first communication point P Ａ may notify time resources if it is TDD (Time Division Duplex), frequency resources if it is FDD (Frequency Division Duplex), and time and frequency resources if it is FD (Full Duplex / Flexible Duplex). These notifications may be made using at least one of, for example, RRC (Radio Resource Control) signaling, MAC-CE (Medium Access Control-Control Element), PBCH, SIB, SIB1, and DCI (Downlink Control Information).

[0298] Also, the first communication point P Ａ may send a stop trigger to the second communication point P Ｂ to stop the transmission of the on-demand first signal and / or the on-demand first notification information by the second communication point P. Also, the first communication point P Ｂ may receive a stop trigger from the UE Ａ for the second communication point P Ａ and, when receiving a stop trigger from the UE Ｂ , the first communication point P Ａ may send a stop trigger to the second communication point P Ａ . Also, the first communication point P Ｂ may send a stop trigger to the second communication point P ＡThe UE sends the stop trigger. Ａ You may also give instructions to the first communication point P. Ａ This is the second communication point P Ｂ In response, resources for receiving a stop trigger may be notified. For example, the first communication point P Ａ In the case of TDD (Time Division Duplex), time resources may be notified; in the case of FDD (Frequency Division Duplex), frequency resources may be notified; and in the case of FD (Full Duplex / Flexible Duplex), time and frequency resources may be notified. Also, the first communication point P Ａ This is the second communication point P Ｂ The signal configuration for the stop trigger may be notified to the first communication point P. Ａ In the case of a Time Division Duplex (TDD), time resources may be notified; in the case of a Frequency Division Duplex (FDD), frequency resources may be notified; and in the case of a Full Duplex / Flexible Duplex (FD), time and frequency resources may be notified. These notifications may be made using, for example, at least one of the following: Radio Resource Control (RRC) signaling, Medium Access Control-Control Element (MAC-CE), PBCH, SIB, SIB1, and Downlink Control Information (DCI).

[0299] Furthermore, the first communication point P Ａ This is the second communication point P Ｂ To put it to sleep or power off, the stop trigger is set to the second communication point P. Ｂ It may also be transmitted to the first communication point P. Ａ If you want to cancel the transmission of the on-demand first signal and / or on-demand first broadcast information to the terminal device 40, you can set a stop trigger at the second communication point P Ｂ It may also be transmitted to the second communication point P. In these cases, the second communication point P ＢA new connection destination (for example, the first communication point P) is requested to the terminal device 40 that is connected to it. Ａ Information to indicate / identify, or another communication point, is sent to the second communication point P. Ｂ The second communication point P may also be notified simultaneously. Ｂ The second communication point P may also notify information for indicating / identifying a new connection destination using an on-demand first signal and / or on-demand first broadcast information. Ｂ The system may notify information for indicating / identifying a new connection destination using at least one of the following: RRC (Radio Resource Control) signaling, MAC-CE (Medium Access Control-Control Element), PBCH, SIB, SIB1, and DCI (Downlink Control Information).

[0300] <5-1-2. Second Communication Point> Second communication point P Ｂ UE Ａ and / or UE Ｂ This is the communication point that will attempt to establish a new connection. Second communication point P Ｂ This may be a base station 20 (or NES cell) with NES (Network Energy Saving) functionality.

[0301] Second communication point P Ｂ The terminal device 40 (for example, UE Ａ and / or UE Ｂ ) may be connected as a first cell (e.g., PCell). Also, a second communication point P Ｂ The terminal device 40 (for example, UE Ａ and / or UE Ｂ ) may be connected as a second cell (e.g., SCell).

[0302] Second communication point P Ｂ The communication coverage is such that all areas are at the first communication point P. Ａ It may be included in the communication coverage, and a portion of the area may be the first communication point P ＡIt may be included in the communication coverage. In the example in Figure 17, the second communication point P Ｂ The entire area of ​​communication coverage C2 is the first communication point P Ａ It is included in the communication coverage C1.

[0303] Also, the second communication point P Ｂ and the first communication point P Ａ These may be included in the same MCG. Also, the first communication point P Ａ It belongs to the MCG (Master Cell Group) and the second communication point P Ｂ It may belong to an SCG (Secondary Cell Group). In this case, the MCG and SCG may have the function of DC (Dual Connectivity).

[0304] Second communication point P Ｂ This corresponds to the transmission of the on-demand first signal and / or the on-demand first broadcast information. Second communication point P Ｂ The initial trigger is set at the first communication point P. Ａ It may also be received from the second communication point P. Ｂ The initial trigger is UE Ａ It is also acceptable to receive from here.

[0305] Furthermore, the second communication point P Ｂ The on-demand first signal and / or on-demand first broadcast information being transmitted is sent to the first communication point P Ａ UE Ａ , and UE Ｂ , to be extended and / or terminated upon request from at least one of the following: Furthermore, the second communication point P Ｂ The extension / stop trigger for extending or stopping the transmission of the on-demand first signal and / or on-demand first broadcast information is set at the first communication point P. Ａ It may also be received from the second communication point P. Ｂ The extension / stop trigger is set by UE Ａ and / or UE Ｂ It may also be received from the second communication point P. ＢUpon receiving an extension / stop trigger, it may send back an ACK (indication of extension / stop) for confirmation. For example, at the second communication point P Ｂ The ACK for confirmation may be included in the RAR (Random Access Response), Msg2, or Msg3.

[0306] Also, the second communication point P Ｂ It is also possible to transmit the first signal (e.g., SS, PSS, or SSS) and a part of the first broadcast information (e.g., PBCH) repeatedly (e.g., periodically) as before, and to transmit certain first broadcast information (e.g., SIB1) on demand. In that case, the second communication point P Ｂ The system uses the first signal (e.g., SS, PSS, or SSS) or a part of the first broadcast information (e.g., PBCH, MIB) to determine the initial trigger signal configuration or the extension / stop trigger signal configuration. Ａ or UE Ｂ It may be possible to notify them.

[0307] <5-1-3. First terminal device (UE Ａ ) > UE Ａ In its initial state, the first communication point P Ａ This is a terminal device 40 that connects wirelessly to the terminal.

[0308] UE Ａ This is the second communication point P Ｂ It has the function of requesting an on-demand first signal and / or on-demand first broadcast information from by transmitting an initial trigger. Ａ The initial trigger is the first communication point P that is connected. Ａ You may send it to UE. Ａ The initial trigger is set at the second communication point P. Ｂ You can also send it directly to UE. Ａ The initial trigger signal configuration is set to the first communication point P Ａ , or the second communication point P Ｂ It can be obtained from. For example, UE Ａ The initial trigger signal configuration can be obtained by the first signal and / or the first broadcast information.Ａ The extension / stop trigger configuration is set at the first communication point P Ａ , or the second communication point P Ｂ It can be obtained from. For example, UE Ａ The signal configuration for the extension / stop trigger can be obtained by the first signal and / or the first notification information.

[0309] Furthermore, UE Ａ The system receives the signal and / or broadcast information triggered by the initial trigger, and a new second communication point P Ｂ It is possible to connect wirelessly.

[0310] <5-1-4. Second terminal device (UE Ｂ ) > UE Ｂ This is the second communication point P Ｂ This is a terminal device 40 that receives the on-demand first signal and / or on-demand first broadcast information from UE. Ｂ This is a terminal device 40 located in a position capable of receiving the on-demand first signal and / or the on-demand first broadcast information. Ｂ This is the first communication point P Ａ It may also be connected to UE. Ｂ UE Ａ For example, you could connect them using a side link.

[0311] UE Ｂ The extension / stop trigger for extending or stopping the transmission of the on-demand first signal and / or on-demand first broadcast information is located at the second communication point P. Ｂ It can be sent directly to UE. Ｂ The extension / stop trigger is set at the first communication point P Ａ or UE Ａ via the second communication point P Ｂ It can be sent directly to UE. Ｂ The signal configuration for the extension / stop trigger can be obtained by the on-demand first signal and / or on-demand first broadcast information. Ｂ The signal configuration for the extension / stop trigger is set at the first communication point P Ａ You can obtain it from UE ＡYou can also obtain it from UE. Ｂ The signal configuration for the extension / stop trigger may be a pre-defined signal configuration.

[0312] UE Ａ and UE Ｂ These may be different terminal devices 40 or the same terminal device 40. Ａ and UE Ｂ In the case of the same terminal device 40, UE Ｂ (that is, UE Ａ ) can transmit an extension / stop trigger to extend or stop the on-demand first signal and / or on-demand first broadcast information that it has triggered itself.

[0313] Furthermore, UE Ｂ The UE may have been notified in advance from a communication point (e.g., base station 20) of candidate transmission timings (transmission occasions) for the on-demand first signal and / or on-demand first broadcast information (e.g., by the true value of the index or by a pattern). Ｂ The UE may select from candidates the transmission termination timing (transmission termination occasion) for the extended on-demand first signal and / or on-demand first broadcast information, and / or the stop timing (stop occasion) for the on-demand first signal and / or on-demand first broadcast information. Ｂ The selected timing (occasion) may be included in the extend / stop trigger and sent.

[0314] <5-2. Signal Configuration> The signals used in this embodiment are generated by means similar to the signal generation process used in wireless transmissions such as downlink transmission, uplink transmission, and sidelink transmission. The signals / information used in this embodiment may also be generated by means similar to the signal generation process used in IAB. The signal configuration of the signals used in this embodiment will be described below.

[0315] In this section (5-2. Signal Configuration), the first communication point P Ａ , and / or second communication point P ＢThis is sometimes simply called a communication point. Also, in this section, the first communication point P Ａ , and / or the second communication point P Ｂ The communication devices that manage these (for example, the management device 10, base station 20, or relay station 30) are also sometimes referred to as communication points. In this section, the terminal device 40 and the second communication point P Ｂ A communication device that relays communication between two points is also sometimes called a communication point. For example, a terminal device 40 is connected to a second communication point P via a side link, and the terminal device 40 is connected to a second communication point P. Ｂ The trigger signal to the second communication point P Ｂ Other terminal devices 40 that transmit data are sometimes also referred to as communication points.

[0316] <5-2-1. On-Demand First Signal and On-Demand First Broadcast Information> Figures 18 and 20 show examples of timelines related to the transmission of the on-demand first signal / first broadcast information, respectively. Figures 19 and 21 show other examples of timelines related to the transmission of the on-demand first signal / first broadcast information, respectively.

[0317] In the examples shown in Figures 18 to 21, the on-demand first signal / first broadcast information is on-demand SSB / SIB1. However, the on-demand first signal / first broadcast information is not limited to on-demand SSB / SIB1.

[0318] Second communication point P Ｂ Once the transmission of the on-demand first signal and / or on-demand first broadcast information is triggered, the on-demand first signal and / or on-demand first broadcast information may continue to be transmitted repeatedly (e.g., periodically) until the power is turned off, similar to a conventional communication system. For example, the second communication point P Ｂ The system may continue broadcasting the on-demand first signal and / or the on-demand first broadcast information.

[0319] Also, the second communication point P ＢThe system may set a transmission time window and repeatedly (for example, periodically) transmit the on-demand first signal and / or on-demand first broadcast information within that time. Here, the interval (duration) from the start time to the end time of transmission is called the time window length. In the examples of Figures 18 and 19, timing T Ｓ１ Timing T Ｅ１ The interval until (time length L1 shown in Figures 18 and 19) is the time window length. Here, the transmission start time may be referred to as starting point / time, triggering point / time, transmission start resource (e.g., frame / slot / symbol), or time instance A. Similarly, the transmission end time may be referred to as ending point / time, transmission end resource (e.g., frame / slot / symbol), or time instance B.

[0320] (Regarding the transmission start time) Transmission start time (In the examples of Figures 18 and 19, timing T) Ｓ１ The start time of transmission may be determined based on a notification (signal / indication) indicating that an on-demand first signal and / or on-demand first broadcast information will be transmitted. Specifically, the start time of transmission may be at least one of the following (F1) to (F5). In the following description, the notification indicating that an on-demand first signal and / or on-demand first broadcast information will be transmitted (for example, signaling of on-demand SSB indication and / or signaling of on-demand SIB1 indication) may simply be referred to as the transmission notification.

[0321] (F1) A predetermined time after the transmission / reception of the transmission notification. For example, the transmission start time may be a predetermined time after the communication point transmits the transmission notification (for example, after the T frame / slot / symbol). Alternatively, the transmission start time may be a predetermined time after the terminal device 40 receives a notification from the communication point that it will transmit the on-demand first signal and / or on-demand first broadcast information.

[0322] (F2) After a predetermined time has elapsed since the transmission / reception of the ACK in response to the transmission notification, for example, suppose the terminal device 40 receives a transmission notification from the communication point and sends back an ACK (e.g., HARQ-ACK) in response. In this case, the transmission start time may be a predetermined time after the communication point receives the ACK from the terminal device 40 (e.g., after the T frame / slot / symbol). Alternatively, the transmission start time may be a predetermined time after the terminal device 40 sends the ACK to the communication point.

[0323] (F3) After a predetermined time from the generation / recognition of the transmission notification, for example, the transmission start time may be after a predetermined time (for example, after the T frame / slot / symbol) from the time the communication point generates / recognizes the transmission notification.

[0324] (F4) The first transmission timing after a predetermined time has elapsed since the transmission / reception of the transmission notification. For example, suppose that the communication point has previously notified the terminal device 40 of candidate transmission timings (transmission occasions) for the on-demand first signal and / or on-demand first broadcast information. In this case, the transmission start time may be the first transmission timing after a predetermined time has elapsed since the communication point transmitted the transmission notification (for example, after the T frame / slot / symbol). Alternatively, the transmission start time may be the first transmission timing after a predetermined time has elapsed since the terminal device 40 received the transmission notification from the communication point.

[0325] (F5) The first transmission timing after a predetermined time has elapsed since the transmission / reception of the ACK in response to the transmission notification. For example, suppose that the communication point has previously notified the terminal device 40 of candidate transmission timings (transmission occasions) for the on-demand first signal and / or on-demand first broadcast information. Suppose that the terminal device 40 has received a transmission notification from the communication point and has sent back an ACK (e.g., HARQ-ACK) in response. In this case, the transmission start time may be the first transmission timing after a predetermined time has elapsed since the communication point received the ACK from the terminal device 40 (e.g., after the T frame / slot / symbol). Alternatively, the transmission start time may be the first transmission timing after a predetermined time has elapsed since the terminal device 40 sent the ACK to the communication point.

[0326] (Regarding signal configuration information) The on-demand first signal and / or on-demand first broadcast information may include at least one piece of information as signal configuration information: transmission start time, transmission end time, and time window length. Ｂ The system may decide whether to send an extension / stop trigger based on signal configuration information (at least one of the transmission start time, transmission end time, and time window length). The signal configuration information (at least one of the transmission start time, transmission end time, and time window length) may be, for example, the true value of a timestamp. Alternatively, the signal configuration information (at least one of the transmission start time, transmission end time, and time window length) may be the number of transmissions of (periodic) signal / broadcast information within the remaining time window, or a counter for the remaining time. The signal configuration information may also include information about the resources used to transmit the on-demand first signal and / or the on-demand first broadcast information.

[0327] Furthermore, the on-demand first signal and / or on-demand first broadcast information may include information on the signal configuration of the extension / stop trigger. The signal configuration information may include information on the resources used to transmit the on-demand first signal and / or on-demand first broadcast information.

[0328] Furthermore, the on-demand first signal and / or on-demand first broadcast information may include information about the time from the end of transmission of the on-demand first signal and / or on-demand first broadcast information until the communication point goes to sleep or powers off. Alternatively, the on-demand first signal and / or on-demand first broadcast information may include information about the timing (frame / slot / symbol / resource) when the communication point goes to sleep or powers off after the end of transmission of the on-demand first signal and / or on-demand first broadcast information.

[0329] (Regarding the extension of transmission time) The communication point is UE Ｂ When an extension trigger is received from UE, the transmission time may be changed from the original transmission time (time L1 in the examples of Figures 18 and 19) to the extended transmission time (time L2 in the examples of Figures 18 and 19). In other words, the communication point is UE Ｂ When an extension trigger is received, the original transmission end time (in the examples of Figures 18 and 19, timing t) Ｅ１ ) From the extended transmission end time (in the examples of Figures 18 and 19, timing t Ｅ２ The transmission end time may be extended until the original transmission end time (timing t). Ｅ１ ) is the transmission start time (in the examples of Figures 18 and 19, timing t Ｓ１ This could also be the timing when a time equivalent to the time window length (in the examples of Figures 18 and 19, the time length L1) has elapsed from ).

[0330] End time of transmission after extension (timing t) Ｅ２ ) may be at least one of the following (G1) to (G6).

[0331] (G1) Transmission end time after timing extension determined by the timing of the first reception of the on-demand first signal and / or on-demand first broadcast information (timing t Ｅ２ ) may be a timing determined based on the timing of the first reception of the on-demand first signal and / or the on-demand first broadcast information. For example, UE ＢThe reference timing (in the example of Figure 18, timing t) is defined as the timing after a first time (in the example of Figure 18, time length T1a) has elapsed from the timing at which the on-demand first signal and / or on-demand first broadcast information is first received (in the example of Figure 18, timing t) Ｓ２ ) Here, the first time (time length T1a) may be a length of 0 or more. That is, the reference timing may be timing t1 itself, or it may be a timing different from timing t1. In this case, the transmission end time after extension (timing t Ｅ２ ) is the reference timing (timing t Ｓ２ ) may be the timing when a second time (time length T2 shown in Figure 18) has elapsed from ). Here, the second time (time length T2) is UE Ａ In order to ensure the same length of time window, UE Ａ The time window length (time length L1) may be the same length as the time window length for UE. Of course, the second time (time length T2) is UE Ａ The time window length (time length L1) may be longer than the time window length for UE. Also, the second time (time length T2) is UE Ａ It may be shorter than the time window length (time length L1).

[0332] (G2) Transmission end time after timing extension, determined by the transmission / reception timing of the extension trigger (timing t Ｅ２ ) may be a timing determined based on the transmission / reception timing of the extension trigger. For example, UE Ｂ The reference timing (in the example of Figure 18, timing t) is set to the timing after a first time interval (in the example of Figure 18, time length T1b) has elapsed from the timing when the extension trigger was sent (in the example of Figure 18, timing t Ｓ２ Alternatively, the reference timing (in the example of Figure 18, timing t) is set to the timing after a first time (in the example of Figure 18, time length T1b) has elapsed from the timing when the communication point receives the extension trigger (in the example of Figure 18, timing t Ｓ２) Here, the first time (time length T1b) may be a length of 0 or more. That is, the reference timing may be timing t2 itself, or it may be a timing different from timing t2. In this case, the transmission end time after extension (timing t Ｅ２ ) is the reference timing (timing t Ｓ２ ) may also be the timing after a second time has elapsed (time length T2 in the example in Figure 18). Ｂ At least UE Ａ To ensure the same time window length as the first time, the second time (time length T2) is UE Ａ The time window length (time length L1) may be the same length as the time window length for UE. Of course, the second time (time length T2) is UE Ａ The time window length (time length L1) for UE may be longer. Also, the second time (time length T2) is UE Ａ It may be shorter than the time window length (time length L1) for that purpose.

[0333] (G3) The end time of transmission after the timing extension, which is determined by the timing of sending / receiving the transmission notification (timing t Ｅ２ ) may be a timing determined based on the transmission / reception timing of the transmission notification. As described above, the transmission notification is a notification that the on-demand first signal and / or on-demand first broadcast information will be transmitted. For example, UE Ｂ The reference timing is the time when a first period of time has elapsed from the time when the transmission notification is received. Alternatively, the communication point is UE Ｂ The reference timing is defined as the time after a first period of time has elapsed from the time the transmission notification was sent to UE. Here, the first period of time may be 0 or greater in length. In this case, the transmission end time after extension may be the time after a second period of time (time length T2) has elapsed from the reference timing. Note that UE Ｂ At least UE Ａ To ensure the same time window length as the first time, the second time (time length T2) is UE Ａ The time window length (time length L1) may be the same length as the time window length for UE. Of course, the second time (time length T2) is UE ＡThe time window length (time length L1) for UE may be longer. Also, the second time (time length T2) is UE Ａ It may be shorter than the time window length (time length L1) for that purpose.

[0334] (G4) The transmission end time after the timing extension, which is determined from the original transmission end time (timing t Ｅ２ ) is the original transmission end time (in the example of Figure 19, timing t Ｅ１ The timing may be determined based on the original transmission end time (in the example in Figure 19, timing t). Ｅ１ The reference timing is set to the reference timing (timing t). In this case, the transmission end time after extension is set to the reference timing (timing t). Ｅ１ ) may also be the timing when a third time (time length T3 in the example in Figure 19) has elapsed from ). Ｂ At least UE Ａ In order to ensure the same time window length as the previous one, the third time (time length T3) is UE Ａ The time window length (time length L1) may be the same length as the time window length for UE. Of course, the third time (time length T3) is UE Ａ The time window length (time length L1) for UE may be longer. Also, the third time (time length T3) is UE Ａ It may be shorter than the time window length (time length L1) for that purpose.

[0335] (G5) Transmission end time after the specified timing extension (timing t Ｅ２ The end time of transmission after extension may be a timing specified by other communication devices / communication points. For example, the end time of transmission after extension may be a timing specified by the information included in the extension trigger. Alternatively, the end time of transmission after extension may be a timing when the time (or frame / slot / symbol / resource) specified by the information included in the extension trigger has elapsed from the reference timing. Furthermore, the end time of transmission after extension may be a timing when the on-demand first signal and / or on-demand first broadcast information has been transmitted the number of times specified by the information included in the extension trigger, from the reference timing. The reference timing may be the same timing as the reference timing shown in (G1) to (G4) above.

[0336] (G6) Other timing extensions and transmission end time (timing t Ｅ２ ) is not limited to the above timing. For example, UE Ｂ However, assume that the communication point has notified in advance of candidate transmission timings (transmission occasions) for the on-demand first signal and / or on-demand first broadcast information. In this case, the extended transmission end time may be any timing (occasion) selected from among the candidates.

[0337] (Regarding the suspension of transmission) The communication point is UE Ｂ When a stop trigger is received from UE, the transmission of the first signal and / or on-demand first broadcast information may be stopped. For example, the communication point is UE Ｂ When a stop trigger is received from UE, the transmission time may be changed from the original transmission time (time L1 / time L2 in the examples of Figures 20 and 21) to the shortened transmission time (time L3 in the examples of Figures 20 and 21). That is, the communication point is UE Ｂ When a stop trigger is received, the original transmission end time (in the examples of Figures 20 and 21, timing t) Ｅ１ / timing t Ｅ２ ) set to a different transmission end time (in the example of Figures 20 and 21, timing t Ｅ３ ) may be changed to ). Here, the original transmission end time is the transmission end time before it is extended by the extension trigger (timing t Ｅ１ ) or the transmission end time after being extended by the extension trigger (timing t Ｅ２ ) is also acceptable.

[0338] The revised transmission end time may be at least one of the following (H1) to (H6).

[0339] (H1) Transmission end time after timing change (timing t) determined by the initial reception timing of the on-demand first signal and / or on-demand first broadcast information. Ｅ３ ) may be a timing determined based on the timing of the first reception of the on-demand first signal and / or the on-demand first broadcast information. For example, UEＢ The reference timing (in the example of Figure 20, timing t) is defined as the timing after a first time (in the example of Figure 20, time length T1a) has elapsed from the timing at which the on-demand first signal and / or on-demand first broadcast information is first received (in the example of Figure 20, timing t) Ｓ２ ) Here, the first time (time length T1a) may be a length of 0 or more. That is, the reference timing may be timing t1 itself, or it may be a timing different from timing t1. In this case, the modified transmission end time (timing t Ｅ３ ) is the reference timing (timing t Ｓ２ The timing may also be obtained by subtracting a fourth time (time length T4 shown in Figure 20) from ).

[0340] (H2) Transmission end time after timing change, determined by the transmission / reception timing of the stop trigger (timing t Ｅ３ ) may be a timing determined based on the transmission / reception timing of the stop trigger. For example, UE Ｂ The timing after a first time interval (time length T1b in the example of Figure 20) has elapsed from the timing when the stop trigger was sent (timing t2 in the example of Figure 20) is defined as the reference timing (timing t in the example of Figure 20). Ｓ２ Alternatively, the reference timing (in the example of Figure 20, timing t) is set to the timing after a first time (in the example of Figure 20, time length T1b) has elapsed from the timing when the communication point receives the stop trigger (in the example of Figure 20, timing t Ｓ２ ) Here, the first time (time length T1b) may be a length of 0 or more. That is, the reference timing may be timing t2 itself, or it may be a timing different from timing t2. In this case, the modified transmission end time (timing t Ｅ３ ) is the reference timing (timing t Ｓ２ The timing may also be obtained by subtracting a fourth time (time length T4 in the example in Figure 20) from ).

[0341] (H3) The end time of transmission after the timing change, which is determined by the transmission / reception timing of the transmission notification (timing t Ｅ３) may be a timing determined based on the transmission / reception timing of the transmission notification. As described above, the transmission notification is a notification that the on-demand first signal and / or on-demand first broadcast information will be transmitted. For example, UE Ｂ The reference timing is the time when a first period of time has elapsed from the time when the transmission notification is received. Alternatively, the communication point is UE Ｂ The reference timing is defined as the time after a first time has elapsed from the time the transmission notification was sent. Here, the first time may be a length of 0 or more. In this case, the modified transmission end time may be the reference timing minus a fourth time (time length T4).

[0342] (H4) The transmission end time after the timing change, which is determined from the original transmission end time (timing t Ｅ３ ) is the original transmission end time (in the example in Figure 21, timing t Ｅ１ / timing t Ｅ２ The timing may be determined based on the original transmission end time (in the example in Figure 21, timing t). Ｅ１ / timing t Ｅ２ The reference timing is set to the reference timing (timing t). In this case, the transmission end time after the change is set to the reference timing (timing t). Ｅ１ / timing t Ｅ２ The timing may be obtained by subtracting a predetermined time (in the example in Figure 21, the time length T5) from ).

[0343] (H5) Transmission end time after the specified timing change (timing t Ｅ３ The timing may be specified by other communication devices / communication points. For example, the modified transmission end time may be specified by the information included in the stop trigger. Alternatively, the modified transmission end time may be the reference timing minus the time (or frame / slot / symbol / resource) specified by the information included in the stop trigger. The reference timing may be the same timing as the reference timing shown in (H1) to (H4) above.

[0344] (H6) Transmission end time after other timing changes (timing t Ｅ３ ) is not limited to the above timing. For example, UE Ｂ However, assume that the communication point has notified in advance of candidate transmission timings (transmission occasions) for the on-demand first signal and / or on-demand first broadcast information. In this case, the extended transmission end time may be any timing (occasion) selected from among the candidates.

[0345] <5-2-2. Initial Trigger> Next, the signal configuration of the initial trigger will be explained. The signal configuration of the initial trigger may also be referred to as the WUS configuration.

[0346] (UE Ａ Initial trigger sent from UE Ａ From the first communication point P Ａ , and / or the second communication point P Ｂ It may be sent to the initial trigger UE Ａ When transmitted from, the initial trigger may have a signal configuration similar to that of PRACH, Msg1, Msg3, PUCCH, and PUSCH. Alternatively, the initial trigger may be included in any of PRACH, Msg1, Msg3, PUCCH, and PUSCH.

[0347] (Initial trigger transmitted from the first communication point) The initial trigger is transmitted from the first communication point P Ａ From the second communication point P Ｂ It may be sent to [location]. In this case, the initial trigger may be sent using backhaul and / or IAB.

[0348] (Notification of initial trigger signal configuration) The initial trigger signal configuration is the first communication point P Ａ From UE Ａ Notification may be given to the first communication point P. In this case, the first communication point P ＡThe initial trigger signal configuration may be notified using PBCH, SIB, or PDCCH, etc. The initial trigger signal configuration may also be predefined. Furthermore, the initial trigger signal configuration is communicated to the second communication point P Ｂ From UE Ａ It may be notified to the second communication point P. Ｂ The initial trigger signal configuration may be notified by the first signal and / or the first notification information. The notification of the signal configuration may include information to explicitly or implicitly identify the second communication point to which the new connection will be made.

[0349] <5-2-3. Extended Trigger> Next, we will explain the signal configuration of the extended trigger.

[0350] (UE Ａ or UE Ｂ (Extension trigger sent from UE) The extension trigger is UE Ｂ From the first communication point P Ａ , second communication point P Ｂ , and UE Ａ , may be sent to at least one of the following. Also, the extension trigger is UE Ａ From the first communication point P Ａ , and / or second communication point P Ｂ It may be sent to [a specific address].

[0351] Extended trigger is UE Ａ or UE Ｂ When transmitted from, the extension trigger may have a signal configuration similar to any of PRACH, Msg1, Msg3, PUCCH, PUSCH, Sidelink, and UL-WUS. Alternatively, the extension trigger may be included in any of PRACH, Msg1, Msg3, PUCCH, PUSCH, Sidelink, and UL-WUS. The extension trigger may contain instruction information for extension or stop. For example, the extension trigger may contain information about the transmission extension time. For example, the extension trigger may contain information indicating how long to extend the transmission time.

[0352] (Extension trigger transmitted from the first communication point) The extension trigger is transmitted from the first communication point P Ａ From the second communication point P Ｂ It may be sent to the backhaul and / or IAB. The extension trigger may contain information indicating whether to extend or stop. For example, the extension trigger may contain information about the transmission extension time. For example, the extension trigger may contain information indicating how long to extend the transmission time.

[0353] (Notification of the signal configuration for the extension trigger) The signal configuration for the extension trigger is as follows: First communication point P Ａ From UE Ａ or UE Ｂ Notification may be given to the first communication point P. In this case, the first communication point P Ａ The signal configuration of the extension trigger may be notified using PBCH, SIB, or PDCCH, etc. The signal configuration of the extension trigger may also be predefined. Furthermore, the signal configuration of the extension trigger is communicated to the second communication point P Ｂ From UE Ａ or UE Ｂ It may be notified to the second communication point P. Ｂ The signal configuration of the extension trigger may be notified by the first signal and / or the first notification information. The notification of the signal configuration may include information to explicitly or implicitly identify the second communication point to which the new connection destination will be. Ｂ The signal configuration of the extension trigger may be notified by the on-demand first signal and / or on-demand first broadcast information.

[0354] <5-2-4. Stop Trigger> Next, we will explain the signal configuration of the stop trigger.

[0355] (UE Ａ or UE Ｂ (Stop trigger sent from UE) The stop trigger is sent from UE Ｂ From the first communication point P Ａ , second communication point PＢ , and UE Ａ , may be sent to at least one of the following. Also, the stop trigger is UE Ａ From the first communication point P Ａ , and / or second communication point P Ｂ It may be sent to [a specific address].

[0356] The stop trigger is UE Ａ or UE Ｂ When transmitted from, the stop trigger may have a signal configuration similar to any of PRACH, Msg1, Msg3, PUCCH, PUSCH, Sidelink, and UL-WUS. Alternatively, the stop trigger may be included in any of PRACH, Msg1, Msg3, PUCCH, PUSCH, Sidelink, and UL-WUS. The stop trigger may contain instruction information regarding stopping. For example, the stop trigger may contain information regarding the transmission stop time. For example, the stop trigger may contain information indicating what time should be the transmission end time.

[0357] (Stop trigger transmitted from the first communication point) The stop trigger is transmitted from the first communication point P Ａ From the second communication point P Ｂ It may be sent to the backhaul and / or IAB. The stop trigger may contain instructions regarding the stop. For example, the stop trigger may contain information about the transmission stop time. For example, the stop trigger may contain information indicating what time should be the transmission end time.

[0358] (Notification of stop trigger signal configuration) The stop trigger signal configuration is communicated at the first communication point P Ａ From UE Ａ or UE Ｂ Notification may be given to the first communication point P. In this case, the first communication point P ＡThe signal configuration for the stop trigger may be notified using PBCH, SIB, or PDCCH, etc. The signal configuration for the stop trigger may also be predefined. Furthermore, the signal configuration for the stop trigger is communicated to the second communication point P Ｂ From UE Ａ or UE Ｂ It may be notified to the second communication point P. Ｂ The signal configuration of the stop trigger may be notified by the first signal and / or the first notification information. The notification of the signal configuration may include information to explicitly or implicitly identify the second communication point to which the new connection destination will be. Ｂ The signal configuration of the stop trigger may be notified by the on-demand first signal and / or on-demand first notification information.

[0359] <5-2-5. Others> (Differences between initial trigger and extension / stop trigger) Initial triggers and extension / stop triggers differ, for example, in their roles and purposes. Also, initial triggers and extension / stop triggers may differ in the information they contain (e.g., the time information to be extended, and / or the transmission end time). Furthermore, initial triggers and extension / stop triggers may differ in at least one of the signal configurations they use, for example, in the frequency resources (e.g., at least one of subcarriers and subcarrier indices), time resources (e.g., at least one of time indices, frames, slots, and symbols), and time-frequency resources (e.g., resource blocks, and / or resource elements).

[0360] <5-3. Overview of Communication System Operation> As mentioned above, if communication points are operated on demand, high-performance wireless communication may not be achievable.

[0361] For example, UE Ａ The initial trigger from the second communication point P Ｂ Assume that it is activated. In this case, the second communication point P Ｂ UE that activated ＡFor the first on-demand signal and / or the first on-demand broadcast information, the second communication point P Ｂ Therefore, it is assumed that it will be transmitted at the appropriate timing and with an appropriate time window length. However, later the second communication point P Ｂ UE connects Ｂ For UE Ｂ Even if UE receives the on-demand first signal and / or on-demand first broadcast information, Ｂ They don't know when it will stop sending. Or, even if they did know, UE Ｂ There is no way to extend it. UE Ｂ During the execution of the initial access process for the second communication point P Ｂ If it stops working, then UE Ｂ This could lead to processing failures. If this happens, high-performance wireless communication cannot be achieved.

[0362] Second communication point P Ｂ To ensure that the connection process to UE is successful, Ｂ The connection procedure must be performed from the beginning. For example, UE Ｂ Even if it is possible to receive the triggered signal and / or broadcast information, UE Ｂ The connection procedure must be performed from the beginning. For example, UE Ｂ This involves identifying the communication point, obtaining the initial trigger configuration, sending the initial trigger, and the second communication point P. Ｂ Initial access to the system (e.g., wake up, activation, and ACK transmission) needs to be performed. This can result in unnecessary delays.

[0363] In addition, in some cases, a second communication point P Ｂ Even though the on-demand first signal and / or on-demand first broadcast information is being repeatedly transmitted as requested, it is conceivable that this may become unnecessary during repeated transmission. In this case, the second communication point P ＢThis results in unnecessarily repeated transmissions. As a result, high communication performance (e.g., low power consumption or low processing load) cannot be achieved in wireless communication.

[0364] To solve these problems, UE Ａ and / or UE Ｂ It is desirable that the transmission of the on-demand first signal and / or the on-demand first broadcast information can be extended or stopped depending on the state (condition). Therefore, in this embodiment, a signal (extension / stop trigger) for triggering the extension or stop of the on-demand first signal and / or the on-demand first broadcast information is proposed.

[0365] For example, UE Ｂ This is the second communication point P Ｂ By sending an extension trigger, the second communication point P can be accessed without having to perform the connection procedure from the beginning. Ｂ Connection to (e.g., Camping) becomes possible. In other words, using an extended trigger, UE Ｂ Conventionally, the second communication point P Ｂ The process required to connect to (for example, the second communication point P) Ｂ The indication (identification) of, and the second communication point P Ｂ The wake-up / activation process can be omitted. As a result, initial access can be made more efficient, enabling high-performance wireless communication.

[0366] Also, for example, UE Ｂ This is the second communication point P Ｂ By sending a stop trigger, the transmission of the on-demand first signal and / or on-demand first broadcast information can be stopped. This stops the transmission of the second communication point P Ｂ Since less signal / notification information is transmitted unnecessarily, high-performance wireless communication (e.g., low power consumption or low processing load) is achieved.

[0367] In the example above, UE Ｂ The second communication point P ＢAn extension / stop trigger was sent to UE. However, the communication device that sends the extension / stop trigger is UE Ｂ Not limited to UE Ａ However, the second communication point P Ｂ An extension / stop trigger may be sent to the first communication point P. Ａ The second communication point P Ｂ You may also send an extension / stop trigger.

[0368] The above describes the general operation of the communication system 1. Below, the operation of the communication system 1 will be described in detail. Below, the description will be divided into three embodiments depending on the difference in the entity (terminal device 40 / communication point) that transmits the trigger signal. In the first embodiment, UE Ａ The initial trigger is sent, UE Ｂ The case in which the extension / stop trigger is transmitted will be described. In the second embodiment, the first communication point P Ａ The initial trigger is sent, UE Ｂ The case in which the extension / stop trigger is transmitted will be described. In the third embodiment, the first communication point P Ａ This section describes the cases in which the initial trigger and extension / stop triggers are sent. Note that these embodiments (the first to third embodiments) can be combined as appropriate.

[0369] <5-4. First Embodiment> First, the operation of the communication system 1 according to the first embodiment will be explained.

[0370] As described above, in the first embodiment, UE Ａ The initial trigger is sent, UE Ｂ It sends an extension / stop trigger.

[0371] UE Ｂ This is the second communication point P Ｂ To that end, an extension / stop trigger is sent directly or indirectly. Ｂ This includes other entities (for example, the first communication point P). Ａ and / or other terminal devices 40 (e.g., UE Ａ Without going through the second communication point P ＢYou may send an extension / stop trigger to the second communication point P via another entity. Ｂ You may also send an extension / stop trigger.

[0372] The signal configuration for the extension / stop trigger may be based on the configuration of the uplink signals from the terminal device 40, such as PRACH, Msg1, Msg3, Sidelink, PUCCH, or UL-WUS.

[0373] In this case, the signal configuration for the extension / stop trigger is determined by the on-demand first signal and / or on-demand first broadcast information. Ｂ It may also be notified to the first communication point P. Ａ or second communication point P Ｂ From, UE Ｂ Notification may be given to the first communication point P. In this case, the first communication point P Ａ or second communication point P Ｂ The signal configuration for the extension trigger may be notified using RRC, MAC-CE, PBCH, SIB, SIB1, or DCI, etc. The signal configuration for the extension / stop trigger may also be predefined. Furthermore, the signal configuration for the extension / stop trigger may be UE Ａ From side link via UE Ｂ UE may be notified. Ｂ It may generate extension / stop triggers based on the notified signal configuration information.

[0374] Note UE Ｂ UE Ａ The same recipient from whom the initial trigger was sent (for example, the first communication point P) Ａ or second transmission point P Ｂ You may also send an extension / stop trigger to ). Ｂ This is the first communication point P Ａ or second communication point P Ｂ You may also send an extension / stop trigger to UE. Ｂ UE Ａ You may also send an extension / stop trigger.

[0375] <5-4-1. Sending conditions for extension / stop triggers> Sending conditions for extension / stop triggers (UE Ｂ The conditions under which the extension / stop trigger is sent, or the conditions under which the extension / stop trigger can be sent, may be when one or more of the following conditions selected from (I1) to (I6) are met.

[0376] (I1)UE Ｂ However, UE Ａ The situation in which the on-demand first signal and / or on-demand first broadcast information that was initially triggered are actually being received.

[0377] (I2)UE Ｂ However, this occurs within a predetermined time (for example, N frames / slot / symbol (N < time window length)) after receiving the on-demand first signal and / or the on-demand first broadcast information.

[0378] (I3)UE Ｂ The on-demand first signal and / or on-demand first broadcast information received is the last of the signal / broadcast information that is repeatedly (e.g., periodically) transmitted within a time window.

[0379] (I4)UE Ｂ The on-demand first signal and / or on-demand first broadcast information received is a certain number of times before / after a predetermined transmission cycle (e.g., the first / last transmission cycle) within the time window.

[0380] (I5)UE Ｂ The on-demand first signal and / or on-demand first broadcast information received is a certain period before / after the above-mentioned reference timing (e.g., transmission end timing).

[0381] (I6)UE Ｂ However, UE Ａ When an initial trigger sent from is received.

[0382] Furthermore, the information necessary to determine whether the conditions shown in (I2) to (I5) are met (for example, information regarding the execution period of repeated transmission (for example, periodic transmission)) may be included in the on-demand first signal and / or on-demand first broadcast information. Here, the information regarding the execution period of repeated transmission may be information regarding the time window length / transmission end timing (transmission end time).

[0383] Also, UE Ｂ The first communication point P Ａ When sending an extension / stop trigger, the conditions for sending the extension / stop trigger may include the conditions shown in (I7) below, in addition to the above conditions (one or more conditions selected from (I1) to (I6)).

[0384] (I7) When the timing advance and / or time margin meet the specified criteria. For example, UE Ｂ The first communication point P Ａ When sending an extension / stop trigger, the first communication point P Ａ From the second communication point P Ｂ An extension / stop trigger will be sent. Therefore, timing advance and / or time margin may be added to the conditions to account for delays.

[0385] Also, UE Ｂ The second communication point P Ｂ When sending an extension / stop trigger, the conditions for sending the extension / stop trigger may include the conditions shown in (I8) below, in addition to the above conditions (one or more conditions selected from (I1) to (I6)).

[0386] (I8) From the end time of transmission of the on-demand first signal and / or the on-demand first broadcast information, the second communication point P Ｂ Until it goes to sleep or powers off, UE Ｂ The extension / stop trigger from the second communication point P Ｂ If it reaches here, then from the end time of transmission, the second communication point P ＢThe time information until sleep or power off is transmitted via the on-demand first signal and / or on-demand first broadcast information, PDCCH, or RRC, etc. Ｂ It may be conveyed to them.

[0387] Also, UE Ｂ ga UE Ａ When sending an extension / stop trigger, the conditions for sending the extension / stop trigger may include the conditions shown in (I9) below, in addition to the above conditions (one or more conditions selected from (I1) to (I6)).

[0388] (I9)UE Ｂ The on-demand first signal and / or on-demand first broadcast information are received, and UE Ｂ UE that can be connected via side link Ａ If there is a UE that can be connected via side link. Ａ This may be a terminal device 40 connected to a communication point that transmits the on-demand first signal and / or the on-demand first broadcast information.

[0389] The following are examples of communication processing sequences (Sequence Examples 1 to 5) according to the first embodiment.

[0390] <5-4-2. Sequence Example 1 of the First Embodiment> First, the communication process (connection process) related to Sequence Example 1 of the First Embodiment will be explained.

[0391] In Sequence Example 1, UE Ｂ This is the second communication point P Ｂ Send an extension trigger directly to it. In Sequence Example 1, UE Ａ and UE Ｂ These are different terminal devices 40.

[0392] Figure 22 is a sequence diagram showing the communication processing according to sequence example 1 of the first embodiment. The control of the sequence shown in Figure 22 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control units of each of the two UEs (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0393] First, UE Ａ This is the second communication point P Ｂ An initial trigger is sent to (steps S101A and S101B). In the example in Figure 22, UE Ａ This is the first communication point P Ａ via the second communication point P Ｂ An initial trigger is being sent to UE. However, UE Ａ This is the second communication point P Ｂ Alternatively, you can send the initial trigger directly.

[0394] Second communication point P Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S102). Ａ This is the second communication point P Ｂ Connect to it.

[0395] UE Ｂ This is the second communication point P Ｂ The on-demand first signal and / or on-demand first broadcast information transmitted from the second communication point P is received. Ｂ Attempting to connect to UE. Ｂ Initially, the first communication point P Ａ It may also be connected to UE. Ｂ It may also be determined whether an extension request is possible (step S103). For example, UE ＢThis may involve determining whether or not the above-mentioned transmission conditions are met.

[0396] At this time, UE Ｂ The system may determine whether an extension request is possible based on the information contained in the received on-demand first signal and / or on-demand first broadcast information (for example, information regarding the duration of repeated transmissions (e.g., periodic transmissions)). Here, the information regarding the duration of repeated transmissions may be information regarding the time window length / transmission end timing (transmission end time).

[0397] Furthermore, the on-demand first signal and / or on-demand first broadcast information includes the second communication point P from the end of repeated transmission. Ｂ It may include information about the time until it goes to sleep or powers off. And UE Ｂ This is from the end of repeated transmission to the second communication point P Ｂ Whether an extension request is possible may be determined based on information regarding the time until the device goes to sleep or powers off.

[0398] UE Ｂ The signal configuration of the extension trigger may be obtained from the received on-demand first signal and / or on-demand first broadcast information. Ｂ The first communication point P to which it is connected Ａ You may request an extended trigger signal configuration (step S104). For example, UE Ｂ The extended trigger signal configuration may be requested through RRC, MAC-CE, PUCCH, CSI, CSI report, PRACH, or RACH, etc. Ｂ This is the first communication point P Ａ The signal configuration of the extension trigger may be obtained from (step S105). For example, UE Ｂ The signal configuration of the extended trigger may be obtained through RRC, MAC-CE, PBCH, SIB, SIB1, DCI, or RAR, etc.

[0399] If an extension request is possible, UE Ｂ The extension trigger is set to the second communication point P ＢIt is sent to (step S106). Note that the extension trigger is the second communication point P Ｂ It may also play a role related to initial access, such as transmitting signals / information for connection (e.g., transmitting PRACH, Msg1, or Msg3). In this case, UE Ｂ In step S106, the second communication point P Ｂ It may also be possible to perform processes that connect to it (for example, initial access processing).

[0400] Second communication point P Ｂ Upon receiving an extension trigger, the transmission of the on-demand first signal and / or on-demand first broadcast information is extended. Here, the extension amount (extension time length) may be a fixed amount, or UE Ｂ This may be a specific amount, or an amount specified by an extension trigger. Second communication point P Ｂ When the extended transmission end time (transmission end timing) arrives, the transmission of the on-demand first signal and / or the on-demand first broadcast information is stopped (step S107).

[0401] Second communication point P Ｂ The device may go into sleep mode or power off after ceasing transmission of the on-demand first signal and / or on-demand first broadcast information. Here, the time from ceasing transmission to sleep mode or power off may be a fixed amount or an amount indicated by an extension trigger. Also, the second communication point P Ｂ The device may go into sleep mode or power off after receiving an extension trigger from another terminal device 40.

[0402] <5-4-3. Sequence Example 2 of the First Embodiment> Next, the communication processing (connection processing) related to Sequence Example 2 of the First Embodiment will be explained.

[0403] In Sequence Example 2, UE Ｂ This is the first communication point P Ａ via the second communication point P Ｂ Send an extension trigger to UE. In Sequence Example 2, Ａ and UE Ｂ These are different terminal devices 40.

[0404] Figure 23 is a sequence diagram showing the communication processing according to sequence example 2 of the first embodiment. The control of the sequence shown in Figure 23 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control units of each of the two UEs (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0405] First, UE Ａ This is the second communication point P Ｂ Send an initial trigger to (steps S101A and S101B). UE Ａ This is the first communication point P Ａ via the second communication point P Ｂ An initial trigger may be sent to the second communication point P. Ｂ Alternatively, an initial trigger may be sent directly to the second communication point P. Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S102). Ａ This is the second communication point P Ｂ Connect to it.

[0406] UE Ｂ It may also be determined whether an extension request is possible (step S103). For example, UE Ｂ The above transmission conditions may be determined to determine whether or not they are met. Ｂ The system may determine whether an extension request is possible based on the information contained in the received on-demand first signal and / or on-demand first broadcast information (for example, information regarding the duration of repeated transmissions (e.g., periodic transmissions)). Here, the information regarding the duration of repeated transmissions may be information regarding the time window length / transmission end timing (transmission end time).

[0407] Furthermore, the on-demand first signal and / or on-demand first broadcast information includes the second communication point P from the end of repeated transmission. Ｂ It may include information about the time until it goes to sleep or powers off. And UE Ｂ This is from the end of repeated transmission to the second communication point P Ｂ Whether an extension request is possible may be determined based on information regarding the time until the device goes to sleep or powers off.

[0408] UE Ｂ The signal configuration of the extension trigger may be obtained from the received on-demand first signal and / or on-demand first broadcast information. Ｂ The first communication point P to which it is connected Ａ The signal configuration for the extended trigger may be requested (step S104). And UE Ｂ This is the first communication point P Ａ The signal configuration of the extension trigger may be obtained from (step S105).

[0409] If an extension request is possible, UE Ｂ The extension trigger is set to the first communication point P Ａ Send to (step S106A). UE Ｂ Upon receiving an extension trigger from the first communication point P, Ａ The extension trigger is set to the second communication point P Ｂ Send to (step S106B). Here, the first communication point P Ａ From the second communication point P Ｂ The transmission of the extension trigger may be done via backhaul or IAB.

[0410] Second communication point P Ｂ Upon receiving an extension trigger, the transmission of the on-demand first signal and / or on-demand first broadcast information is extended. Second communication point P Ｂ When the extended transmission end time arrives, the transmission of the on-demand first signal and / or on-demand first broadcast information is stopped (step S107). Second communication point P ＢThe device may go into sleep mode or be powered off after it has stopped transmitting the on-demand first signal and / or the on-demand first broadcast information.

[0411] <5-4-4. Sequence Example 3 of the First Embodiment> Next, the communication processing (connection processing) related to Sequence Example 3 of the First Embodiment will be explained.

[0412] In Sequence Example 3, UE Ｂ This is the first communication point P Ａ via the second communication point P Ｂ Send an extension trigger to UE. In Sequence Example 3, Ａ and UE Ｂ These are different terminal devices 40. In sequence example 3, UE Ａ and UE Ｂ It is connected via a side link.

[0413] Figure 24 is a sequence diagram showing the communication processing according to sequence example 3 of the first embodiment. The control of the sequence shown in Figure 24 may be performed, for example, by the control unit of the communication point (e.g., control unit 23) and the control units of each of the two UEs (e.g., control units 43). As described above, the communication point is not limited to the base station 20. For example, the communication point may be an entity controlled by the base station 20 (e.g., a communication node / antenna / TRP / cell (classic cell / beam cell / point cell), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0414] First, UE Ａ This is the second communication point P Ｂ Send an initial trigger to (step S201). UE Ａ This is the first communication point P Ａ via the second communication point P Ｂ An initial trigger may be sent to the second communication point P. Ｂ Alternatively, an initial trigger may be sent directly to the second communication point P. Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S202).Ａ This is the second communication point P Ｂ Connect to it.

[0415] UE Ｂ It may also determine whether an extension request is possible. For example, UE Ｂ The above transmission conditions may be determined to determine whether or not they are met. Ｂ The system may determine whether an extension request is possible based on the information contained in the received on-demand first signal and / or on-demand first broadcast information (for example, information regarding the duration of repeated transmissions (e.g., periodic transmissions)). Here, the information regarding the duration of repeated transmissions may be information regarding the time window length / transmission end timing (transmission end time).

[0416] Furthermore, the on-demand first signal and / or on-demand first broadcast information includes the second communication point P from the end of repeated transmission. Ｂ It may include information about the time until it goes to sleep or powers off. And UE Ｂ This is from the end of repeated transmission to the second communication point P Ｂ Whether an extension request is possible may be determined based on information regarding the time until the device goes to sleep or powers off.

[0417] UE Ｂ The signal configuration of the extension trigger may be obtained from the received on-demand first signal and / or on-demand first broadcast information. Ｂ UE via side links Ａ You may request the signal configuration for the extended trigger. Upon receiving the request for the signal configuration, UE Ａ The second communication point P is connected to Ｂ From this, the signal configuration of the extension trigger may be obtained. For example, UE Ａ The extended trigger signal configuration may be requested through RRC, MAC-CE, PUCCH, CSI, CSI report, PRACH, or RACH, etc. Ａ The signal configuration of the extended trigger may be obtained through RRC, MAC-CE, PBCH, SIB, SIB1, DCI, or RAR, etc.Ｂ UE Ａ The signal configuration for the extended trigger may be obtained from there.

[0418] If an extension request is possible, UE Ｂ The extension trigger (extension request) is set by UE Ａ Send to (step S203). UE Ｂ When an extension trigger (extension request) is received from UE Ａ The extension trigger is set to the second communication point P Ｂ Send to (step S204). At this time, UE Ａ RRC, MAC-CE, PUCCH, CSI, CSI report, PRACH, or RACH may transmit an extended trigger using the base signal.

[0419] Upon receiving the extension trigger, the second communication point P Ｂ This extends the transmission of the on-demand first signal and / or the on-demand first broadcast information. Second communication point P Ｂ When the extended transmission end time arrives, the transmission of the on-demand first signal and / or on-demand first broadcast information is stopped (step S205). Second communication point P Ｂ The device may go into sleep mode or be powered off after it has stopped transmitting the on-demand first signal and / or the on-demand first broadcast information.

[0420] <5-4-5. Sequence Example 4 of the First Embodiment> Next, the communication processing (connection processing) related to Sequence Example 4 of the First Embodiment will be explained.

[0421] In Sequence Example 4, UE Ｂ This is the second communication point P Ｂ Send an extension trigger directly to UE. In Sequence Example 4, UE Ａ and UE Ｂ This is the same terminal device 40. In the following explanation, UE Ｂ This is simply called UE.

[0422] Figure 25 is a sequence diagram showing the communication processing according to sequence example 4 of the first embodiment. The control of the sequence shown in Figure 25 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control unit of the UE (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0423] First, UE is at the second communication point P Ｂ An initial trigger is sent to (step S301). The UE sends an initial trigger to the first communication point P Ａ via the second communication point P Ｂ An initial trigger may be sent to the second communication point P. Ｂ Alternatively, an initial trigger may be sent directly to the second communication point P. Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S302). Then, the UE communicates with the second communication point P Ｂ Connect to it.

[0424] The UE may determine whether an extension request is possible. For example, the UE may determine whether the above-described transmission conditions are met. In this case, the UE may determine whether an extension request is possible based on the information contained in the received on-demand first signal and / or on-demand first broadcast information (for example, information regarding the duration of repeated transmission (e.g., periodic transmission)). Here, the information regarding the duration of repeated transmission may be information on the time window length / transmission end timing (transmission end time).

[0425] The UE may obtain the signal configuration of the extension trigger from the received on-demand first signal and / or on-demand first broadcast information. The UE may also obtain the signal configuration of the extension trigger from the connected second communication point P. ＢThe UE may request the signal configuration for the extended trigger (step S303A). For example, the UE may request the signal configuration for the extended trigger through RRC, MAC-CE, PUCCH, CSI, CSI report, PRACH, or RACH, etc. Ｂ This is the second communication point P Ｂ The signal configuration for the extended trigger may be obtained from (step S304A). For example, the UE may obtain the signal configuration for the extended trigger through RRC, MAC-CE, PBCH, SIB, SIB1, DCI, or RAR.

[0426] If an extension request is possible, the UE will trigger the extension at the second communication point P. Ｂ Send to the second communication point P (step S305A). Ｂ Upon receiving an extension trigger, the transmission of the on-demand first signal and / or on-demand first broadcast information is extended. Here, the extension amount (extension time length) may be a fixed amount, an amount specific to the UE, or an amount specified by the extension trigger. Second communication point P Ｂ When the extended transmission end time (transmission end timing) arrives, the transmission of the on-demand first signal and / or on-demand first broadcast information is stopped (step S306A). Second communication point P Ｂ The device may go into sleep mode or be powered off after it has stopped transmitting the on-demand first signal and / or the on-demand first broadcast information.

[0427] <5-4-6. Sequence Example 5 of the First Embodiment> Next, the communication processing (connection processing) related to Sequence Example 5 of the First Embodiment will be explained.

[0428] Sequence Examples 1 to 4 show UE Ｂ This is the second communication point P Ｂ An extension trigger was sent to UE. Ｂ This is the second communication point P Ｂ A stop trigger may be sent to UE. In Sequence Example 5, UE Ｂ This is the second communication point P Ｂ A stop trigger is sent directly to it. In sequence example 5, UEＡ and UE Ｂ This is the same terminal device 40. In the following explanation, UE Ｂ This is simply called UE.

[0429] Figure 26 is a sequence diagram showing the communication processing according to sequence example 5 of the first embodiment. The control of the sequence shown in Figure 26 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control unit of the UE (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0430] First, UE is at the second communication point P Ｂ An initial trigger is sent to (step S301). The UE sends an initial trigger to the first communication point P Ａ via the second communication point P Ｂ An initial trigger may be sent to the second communication point P. Ｂ Alternatively, an initial trigger may be sent directly to the second communication point P. Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S302). Then, the UE communicates with the second communication point P Ｂ Connect to it.

[0431] The UE may determine whether a stop request is possible. For example, the UE may determine whether the above-described transmission conditions are met. In this case, the UE may determine whether a stop request is possible based on the information contained in the received on-demand first signal and / or on-demand first broadcast information (for example, information regarding the execution period of repeated transmission (e.g., periodic transmission)). Here, the information regarding the execution period of repeated transmission may be information on the time window length / transmission end timing (transmission end time).

[0432] Furthermore, the on-demand first signal and / or on-demand first broadcast information includes the second communication point P from the end of repeated transmission. Ｂ The information may include details about the time until the device goes to sleep or is powered off. The UE then travels from the end of repeated transmission to the second communication point P. Ｂ The possibility of a shutdown request may be determined based on information regarding the time remaining until the device goes to sleep or is powered off.

[0433] The UE may obtain the signal configuration of the stop trigger from the received on-demand first signal and / or on-demand first broadcast information. The UE may also obtain the signal configuration of the stop trigger from the second communication point P to which it is connected. Ｂ The UE may request the configuration of the stop trigger signal (step S303B). For example, the UE may request the configuration of the stop trigger signal through RRC, MAC-CE, PUCCH, CSI, CSI report, PRACH, or RACH, etc. Ｂ This is the second communication point P Ｂ The stop trigger signal configuration may be obtained from (step S304B). For example, the UE may obtain the stop trigger signal configuration through RRC, MAC-CE, PBCH, SIB, SIB1, DCI, or RAR.

[0434] If a stop request is possible, the UE will trigger the stop at the second communication point P. Ｂ Send to the second communication point P (step S305B). Ｂ Upon receiving a stop trigger, the transmission of the on-demand first signal and / or on-demand first broadcast information is stopped (step S306B). Here, the stop time (stop timing) may be the timing specified by the stop trigger. Second communication point P Ｂ The device may go into sleep mode or be powered off after it has stopped transmitting the on-demand first signal and / or the on-demand first broadcast information.

[0435] Note that in Sequence Example 5, UE Ａ and UE Ｂ However, the terminal device 40 was the same. Ａ and UE ＢThe terminal device 40 may be different. In this case, the sequence may be the same as the sequence described above (Sequence Examples 1 to 4 of the First Embodiment). In this case, the description of "extend" in the above sequence examples (Sequence Examples 1 to 4 of the First Embodiment) may be changed to "stop" as appropriate.

[0436] <5-5. Second Embodiment> Next, the operation of the communication system 1 according to the second embodiment will be described.

[0437] As described above, in the second embodiment, the first communication point P Ａ The initial trigger is sent, UE Ｂ It sends an extension / stop trigger.

[0438] The signal configuration for the extension / stop trigger may be based on the configuration of the uplink signals from the terminal device 40, such as PRACH, Msg1, Msg3, Sidelink, PUCCH, or UL-WUS.

[0439] In this case, the signal configuration for the extension / stop trigger is determined by the on-demand first signal and / or on-demand first broadcast information. Ｂ It may also be notified to the first communication point P. Ａ or second communication point P Ｂ From, UE Ｂ Notification may be given to the first communication point P. In this case, the first communication point P Ａ or second communication point P Ｂ The signal configuration of the extended trigger may be notified using RRC, MAC-CE, PBCH, SIB, SIB1, or DCI, etc. The signal configuration of the extended trigger may also be predefined. Furthermore, the signal configuration of the extended trigger may be UE Ａ From side link via UE Ｂ You may be notified.

[0440] Note UE Ｂ This is the first communication point P Ａ or second communication point P Ｂ You may also send an extension / stop trigger to UE. Ｂ UE ＡYou may also send an extension / stop trigger.

[0441] <5-5-1. Sending conditions for extension / stop triggers> Sending conditions for extension / stop triggers (UE Ｂ The conditions under which the extension / stop trigger is sent, or the conditions under which the extension / stop trigger can be sent, may be when one or more of the following conditions selected from (J1) to (J7) are met.

[0442] (J1) UE Ｂ However, UE Ａ The situation in which the on-demand first signal and / or on-demand first broadcast information that was initially triggered are actually being received.

[0443] (J2) UE Ｂ However, this occurs within a predetermined time (for example, N frames / slot / symbol (N < time window length)) after receiving the on-demand first signal and / or the on-demand first broadcast information.

[0444] (J3) UE Ｂ The on-demand first signal and / or on-demand first broadcast information received is the last of the signal / broadcast information that is repeatedly (e.g., periodically) transmitted within a time window.

[0445] (J4) UE Ｂ The on-demand first signal and / or on-demand first broadcast information received is a certain number of times before / after a predetermined transmission cycle (e.g., the first / last transmission cycle) within the time window.

[0446] (J5) UE Ｂ The on-demand first signal and / or on-demand first broadcast information received is a certain period before / after the above-mentioned reference timing (e.g., transmission end timing).

[0447] (J6) The first communication point P that transmitted the initial trigger. Ａ However, UE Ｂ A new connection destination (second communication point P) Ｂ If information is provided to indicate (identify) )

[0448] (J7) The first communication point P that transmitted the initial trigger. Ａ However, UE Ｂ When the signal configuration for extension / stop trigger is transmitted to the first communication point P. Ａ However, UE Ｂ When the signal configuration for the extension / stop trigger is transmitted via RRC, MAC-CE, PBCH, SIB, SIB1, DCI, or RAR.

[0449] Furthermore, the information necessary to determine whether the conditions shown in (J2) to (J5) are met (for example, information regarding the duration of repeated transmission (for example, periodic transmission)) may be included in the on-demand first signal and / or on-demand first broadcast information. Here, the information regarding the duration of repeated transmission may be information regarding the time window length / transmission end timing (transmission end time).

[0450] Also, UE Ｂ The first communication point P Ａ When sending an extension / stop trigger, the conditions for sending the extension / stop trigger may include the conditions shown in (J8) below, in addition to the above conditions (one or more conditions selected from (J1) to (J7)).

[0451] (J8) When the timing advance and / or time margin meet the specified criteria. For example, UE Ｂ The first communication point P Ａ When sending an extension / stop trigger, the first communication point P Ａ From the second communication point P Ｂ An extension / stop trigger will be sent. Therefore, timing advance and / or time margin may be added to the conditions to account for delays.

[0452] Also, UE Ｂ The second communication point P Ｂ When sending an extension / stop trigger, the conditions for sending the extension / stop trigger may include the conditions shown in (J9) below, in addition to the above conditions (one or more conditions selected from (J1) to (J7)).

[0453] (J9) From the end time of transmission of the on-demand first signal and / or the on-demand first broadcast information, the second communication point P Ｂ Until it goes to sleep or powers off, UE Ｂ The extension / stop trigger from the second communication point P Ｂ If it reaches here, then from the end time of transmission, the second communication point P Ｂ The time information until sleep or power off is transmitted via the on-demand first signal and / or on-demand first broadcast information, PDCCH, or RRC, etc. Ｂ It may be conveyed to them.

[0454] Also, UE Ｂ ga UE Ａ When sending an extension / stop trigger, the conditions for sending the extension / stop trigger may include the conditions shown in (J10) below, in addition to the above conditions (one or more conditions selected from (J1) to (J7)).

[0455] (J10) UE Ｂ The on-demand first signal and / or on-demand first broadcast information are received, and UE Ｂ UE that can be connected via side link Ａ If there is a UE that can be connected via side link. Ａ This may be a terminal device 40 connected to a communication point that transmits the on-demand first signal and / or the on-demand first broadcast information.

[0456] The following are examples of communication processing sequences (Sequence Examples 1 to 5) according to the second embodiment.

[0457] <5-5-2. Sequence Example 1 of the Second Embodiment> First, the communication process (connection process) related to Sequence Example 1 of the second embodiment will be explained.

[0458] In Sequence Example 1, UE Ｂ This is the second communication point P Ｂ Send an extension trigger directly to it. In Sequence Example 1, UE Ａ and UE Ｂ These are different terminal devices 40.

[0459] Figure 27 is a sequence diagram showing the communication processing according to sequence example 1 of the second embodiment. The control of the sequence shown in Figure 27 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control units of each of the two UEs (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0460] First, the first communication point P Ａ This is the second communication point P Ｂ An initial trigger is sent to the second communication point P (step S101C). Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S102). Ａ This is the second communication point P Ｂ Connect to it.

[0461] Other processes are the same as in Sequence Example 1 of the first embodiment, so their explanation will be omitted.

[0462] <5-5-3. Sequence Example 2 of the Second Embodiment> Next, the communication processing (connection processing) related to Sequence Example 2 of the second embodiment will be explained.

[0463] In Sequence Example 2, UE Ｂ This is the first communication point P Ａ via the second communication point P Ｂ Send an extension trigger to UE. In Sequence Example 2, Ａ and UE Ｂ These are different terminal devices 40.

[0464] Figure 28 is a sequence diagram showing the communication processing according to sequence example 2 of the second embodiment. The control of the sequence shown in Figure 28 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control units of each of the two UEs (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0465] First, the first communication point P Ａ This is the second communication point P Ｂ An initial trigger is sent to the second communication point P (step S101C). Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S102). Ａ This is the second communication point P Ｂ Connect to it.

[0466] Other processes are the same as in Sequence Example 2 of the first embodiment, so their explanation will be omitted.

[0467] <5-5-4. Sequence Example 3 of the Second Embodiment> Next, the communication processing (connection processing) related to Sequence Example 3 of the second embodiment will be explained.

[0468] In Sequence Example 3, UE Ｂ This is the first communication point P Ａ via the second communication point P Ｂ Send an extension trigger to UE. In Sequence Example 3, Ａ and UE Ｂ These are different terminal devices 40. In sequence example 3, UE Ａ and UE Ｂ It is connected via a side link.

[0469] Figure 29 is a sequence diagram showing the communication processing according to sequence example 3 of the second embodiment. The control of the sequence shown in Figure 29 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control units of each of the two UEs (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0470] First, the first communication point P Ａ This is the second communication point P Ｂ Send an initial trigger to the second communication point P (step S201B). Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S202). Ａ This is the second communication point P Ｂ Connect to it.

[0471] Other processes are the same as in Sequence Example 3 of the first embodiment, so their explanation will be omitted.

[0472] <5-5-5. Sequence Example 4 of the Second Embodiment> Next, the communication processing (connection processing) related to Sequence Example 4 of the second embodiment will be explained.

[0473] In Sequence Example 4, UE Ｂ This is the second communication point P Ｂ Send an extension trigger directly to UE. In Sequence Example 4, UE Ａ and UE Ｂ This is the same terminal device 40. In the following explanation, UE Ｂ This is simply called UE.

[0474] Figure 30 is a sequence diagram showing the communication processing according to sequence example 4 of the second embodiment. The control of the sequence shown in Figure 30 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control unit of the UE (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0475] First, the first communication point P Ａ This is the second communication point P Ｂ An initial trigger is sent to the second communication point P (step S301B). Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S302). Then, the UE communicates with the second communication point P Ｂ Connect to it.

[0476] Other processes are the same as in Sequence Example 4 of the first embodiment, so their explanation will be omitted.

[0477] <5-5-6. Sequence Example 5 of the Second Embodiment> Next, the communication process (connection process) related to Sequence Example 5 of the second embodiment will be explained.

[0478] Sequence Examples 1 to 4 show UE Ｂ This is the second communication point P Ｂ An extension trigger was sent to UE. Ｂ This is the second communication point P Ｂ A stop trigger may be sent to UE. In Sequence Example 5, UE Ｂ This is the second communication point P Ｂ A stop trigger is sent directly to it. In sequence example 5, UE Ａ and UE Ｂ This is the same terminal device 40. In the following explanation, UE Ｂ This is simply called UE.

[0479] Figure 31 is a sequence diagram showing the communication processing according to sequence example 5 of the second embodiment. The control of the sequence shown in Figure 31 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control unit of the UE (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0480] First, the first communication point P Ａ This is the second communication point P Ｂ An initial trigger is sent to the second communication point P (step S301B). Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S302). Then, the UE communicates with the second communication point P Ｂ Connect to it.

[0481] Other processes are the same as in Sequence Example 5 of the first embodiment, so their explanation will be omitted.

[0482] Note that in Sequence Example 5, UE Ａ and UE Ｂ However, the terminal device 40 was the same. Ａ and UE Ｂ The terminal devices 40 may be different. In this case, the sequence may be the same as the sequence described in the above sequence examples (sequence examples 1 to 4 of the second embodiment). In this case, the word "extend" that appears in the above sequence examples (sequence examples 1 to 4 of the second embodiment) may be replaced with "stop" as appropriate.

[0483] <5-6. Third Embodiment> Next, the operation of the communication system 1 according to the third embodiment will be described.

[0484] As described above, in the third embodiment, the first communication point P ＡIt sends the initial trigger and the extension / stop trigger.

[0485] In the third embodiment, the first communication point P Ａ For example, via backhaul or IAB, to a second communication point P Ｂ Sends an extension / stop trigger to the UE. In the third embodiment, Ａ and UE Ｂ In the initial state, the first communication point P Ａ It is connected (camping) to the first communication point P. Ａ This is the second communication point P Ｂ In parallel with sending the extension / stop trigger to UE Ｂ Notification may be sent to the first communication point P. Ａ In parallel with sending the extension / stop trigger, UE Ｂ A new second communication point P Ｂ You may send an indication (identification) to connect to it.

[0486] <5-6-1. Transmission conditions for extension / stop trigger> Transmission conditions for extension / stop trigger (First communication point P) Ａ The conditions under which the extension / stop trigger is sent, or the conditions under which the extension / stop trigger can be sent, may be when one or more of the following conditions selected from (K1) to (K5) are met.

[0487] (K1) First communication point P Ａ However, the transmission schedule for the on-demand first signal and / or on-demand first broadcast information (second communication point P Ｂ If you know the sending schedule.

[0488] (K2) First communication point P Ａ However, UE Ｂ If it is aware that it is receiving the on-demand first signal and / or on-demand first broadcast information.

[0489] (K3) First communication point P Ａ However, UE ＢIf it is known that the on-demand first signal and / or on-demand first broadcast information is in a position to be received.

[0490] (K4) First communication point P Ａ However, if it is determined that both (K4-1) and (K4-2) below are satisfied. Note that the first communication point P Ａ For example, the second communication point P will have the following conditions (K4-1) and (K4-2) satisfied. Ｂ It may also be determined based on the transmission schedule. (K4-1)UE Ａ The second communication point P Ｂ The time to receive the on-demand first signal and / or on-demand first broadcast information from UE Ｂ The second communication point P Ｂ The time for receiving the on-demand first signal and / or on-demand first broadcast information overlaps with a portion of the time. (K4-2)UE Ａ The second communication point P Ｂ The time to receive the on-demand first signal and / or on-demand first broadcast information from UE Ｂ The second communication point P Ｂ The time at which the on-demand first signal and / or on-demand first broadcast information are received does not perfectly coincide.

[0491] (K5) First communication point P Ａ However, the second communication point P Ｂ If you want to cancel the transmission of the on-demand first signal and / or on-demand first broadcast information to the terminal device 40 in order to put it to sleep or power it off.

[0492] In the above case, the first communication point P Ａ The extension / stop trigger is set at the second communication point P Ｂ It can transmit to the second communication point P. This allows the terminal device 40 to connect to the second communication point PB using conventional methods. In other words, the terminal device 40 can transmit to the second communication point P without worrying about the remaining transmission time of the on-demand signal / broadcast information. Ｂ It can be connected to.

[0493] The following are examples of communication processing sequences (Sequence Example 1 to Sequence Example 2) according to the third embodiment.

[0494] <5-6-2. Sequence Example 1 of the Third Embodiment> First, the communication process (connection process) related to Sequence Example 1 of the third embodiment will be explained.

[0495] In Sequence Example 1, the first communication point P Ａ This is the second communication point P Ｂ Send an extension trigger to UE. In Sequence Example 1, Ａ and UE Ｂ These are different terminal devices 40.

[0496] Figure 32 is a sequence diagram showing the communication processing according to sequence example 1 of the third embodiment. The control of the sequence shown in Figure 32 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control units of each of the two UEs (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0497] First, the first communication point P Ａ This is the second communication point P Ｂ An initial trigger is sent to (step S101C). Note that UE Ａ However, the second communication point P Ｂ You may send an initial trigger to UE. Ａ This is the second communication point P Ｂ You can also send the initial trigger directly to UE. Ａ This is the first communication point P Ａ via the second communication point P Ｂ You may send an initial trigger to it.

[0498] First communication point P ＢUpon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S102). Ａ This is the second communication point P Ｂ Connect to UE. Ｂ This is the second communication point P Ｂ The on-demand first signal and / or on-demand first broadcast information transmitted from the second communication point P is received. Ｂ Attempting to connect to it.

[0499] First communication point P Ａ The system determines whether an extension request is possible (step S103B). For example, the first communication point P Ａ This determines whether the above transmission conditions are met. If an extension request is possible, the first communication point P Ａ The extension trigger is set to the second communication point P Ｂ Send to (step S106B). First communication point P Ａ In parallel with sending the extension trigger, UE Ｂ Notification may be given to the first communication point P (step S106C). Ａ In parallel with sending the extension / stop trigger, UE Ｂ A new second communication point P Ｂ You may send an indication (identification) to connect to it.

[0500] Second communication point P Ｂ Upon receiving an extension trigger, the transmission of the on-demand first signal and / or on-demand first broadcast information is extended. Here, the extension amount (extension time length) may be a fixed amount, or UE Ｂ This may be a specific amount, or an amount specified by an extension trigger. Second communication point P Ｂ When the extended transmission end time (transmission end timing) arrives, the transmission of the on-demand first signal and / or the on-demand first broadcast information is stopped (step S107).

[0501] Second communication point P ＢThe device may go into sleep mode or power off after ceasing transmission of the on-demand first signal and / or on-demand first broadcast information. Here, the time from ceasing transmission to sleep mode or power off may be a fixed amount or an amount indicated by an extension trigger. Also, the second communication point P Ｂ It may go to sleep or power off after receiving an extension trigger from another entity (for example, terminal device 40 and / or another communication point).

[0502] Note that in Sequence Example 1, UE Ａ and UE Ｂ These were different terminal devices 40. However, UE Ａ and UE Ｂ The terminal device 40 may be the same. In this case, the "UE" that appears in the above sequence example (sequence example 1 of the third embodiment) Ａ " and "UE Ｂ Replace the notation " with "UE" as appropriate.

[0503] <5-6-3. Sequence Example 2 of the Third Embodiment> Next, the communication processing (connection processing) related to Sequence Example 2 of the third embodiment will be explained.

[0504] In Sequence Example 2, the first communication point P Ａ This is the second communication point P Ｂ A stop trigger is sent to the UE. In Sequence Example 2, Ａ and UE Ｂ These are different terminal devices 40.

[0505] Figure 33 is a sequence diagram showing the communication processing according to sequence example 2 of the third embodiment. The control of the sequence shown in Figure 33 may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control units of each of the two UEs (e.g., control unit 43). As described above, the communication points are not limited to the base station 20. For example, the communication points may be entities controlled by the base station 20 (e.g., communication nodes / antennas / TRPs / cells (classic cells / beam cells / point cells), etc.). In this case, the control unit of the communication point may be the control unit of the base station 20 that controls the communication point (e.g., control unit 23).

[0506] First, the first communication point P Ａ This is the second communication point P Ｂ An initial trigger is sent to (step S101C). Note that UE Ａ However, the second communication point P Ｂ You may send an initial trigger to UE. Ａ This is the second communication point P Ｂ You can also send the initial trigger directly to UE. Ａ This is the first communication point P Ａ via the second communication point P Ｂ You may send an initial trigger to it.

[0507] First communication point P Ｂ Upon receiving the initial trigger, the UE starts transmitting the on-demand first signal and / or on-demand first broadcast information (step S102). Ａ and UE Ｂ This is the second communication point P Ｂ Connect to it.

[0508] First communication point P Ａ It is determined whether a stop request is possible (step S103C). For example, the first communication point P Ａ This determines whether the above transmission conditions are met. If a stop request is possible, the first communication point P Ａ The stop trigger is the second communication point P ＢSend to (step S106D). First communication point P Ａ In parallel with sending the stop trigger, UE Ｂ You may also notify them (step S106E).

[0509] Second communication point P Ｂ Upon receiving a stop trigger, the system stops transmitting the on-demand first signal and / or the on-demand first broadcast information (step S107).

[0510] Second communication point P Ｂ The device may go into sleep mode or power off after ceasing transmission of the on-demand first signal and / or on-demand first broadcast information. Here, the time from ceasing transmission to sleeping mode or power off may be a fixed amount or an amount indicated by the ceasing trigger. Also, the second communication point P Ｂ It may go to sleep or power off after receiving a stop trigger from another entity (for example, terminal device 40 and / or another communication point).

[0511] Note that in Sequence Example 2, UE Ａ and UE Ｂ These were different terminal devices 40. However, UE Ａ and UE Ｂ The terminal device 40 may be the same. In this case, the "UE" that appears in the above sequence example (sequence example 2 of the third embodiment) Ａ " and "UE Ｂ Replace the notation " with "UE" as appropriate.

[0512] <<6. Application to Initial Access in Cell-Free Systems>> The above-described method (extension / stopping of transmission of on-demand first signal and / or on-demand first broadcast information by extension / stop trigger) can also be applied to initial access methods in cell-free communication systems (cell-free communication networks). For example, in the initial access methods described below (methods 1 to 4), even when the first signal and / or first broadcast information is made on-demand, the sequences shown in the first to third embodiments can be applied.

[0513] In the following explanation, communication system 1 will be assumed to be a self-free communication system as an example. Furthermore, communication system 1 will consist of, for example, a terminal device 40 (UE shown in Figure 7) and two base stations 20 (BS shown in Figure 7), as shown in Figure 7. １ , and BS ２ ) and shall be provided with the following:

[0514] UE is, for example, UE in the first to third embodiments Ｂ This corresponds to UE. Ｂ The UE that sends the initial trigger Ａ It may be the same terminal device 40, or it may be a different terminal device 40.

[0515] In the following explanation, for example, as shown in Figure 7, BS １ is communication point P １１ ~Communication points P １Ｎ It is assumed to be connected to BS. １ is communication point P １１ ~Communication points P １Ｎ It shall be equipped with BS. １ For example, the first communication point P in the first to third embodiments. Ａ This corresponds to communication point P. １１ ~Communication points P １Ｎ These are, for example, the second communication point P in the first to third embodiments. Ｂ This corresponds to . N is any integer. In the following explanation, BS １ and communication point P １１ ~Communication points P １Ｎ Together, BS １ It is sometimes called that.

[0516] Furthermore, in the following explanation, as shown in Figure 7, for example, BS ２ is communication point P ２１ ~Communication points P ２Ｍ It is assumed to be connected to BS. ２ is communication point P ２１ ~Communication points P ２Ｍ It shall be equipped with BS. ２For example, the first communication point P in the first to third embodiments. Ａ This corresponds to communication point P. ２１ ~Communication points P ２Ｍ These are, for example, the second communication point P in the first to third embodiments. Ｂ This corresponds to M being any integer. In the following explanation, BS ２ and communication point P ２１ ~Communication points P ２Ｍ Together, BS ２ It is sometimes called that.

[0517] As mentioned above, the second communication point P Ｂ It is capable of transmitting an on-demand first signal and / or on-demand first broadcast information. Also, the second communication point P Ｂ The device is capable of transmitting a second signal. The second signal is, for example, one of the signals shown in (E1) to (E4) above. For example, the second signal is a signal for measuring the communication quality of a communication point. The second signal may also be on-demand. In this case, the second signal may be referred to as the on-demand second signal.

[0518] In the following explanation, the on-demand first signal may be simply referred to as the first signal. Similarly, the on-demand first broadcast information may be simply referred to as the first broadcast information. Furthermore, the on-demand second signal may be simply referred to as the second signal.

[0519] The following describes the initial access methods (Method 1 to Method 4) in a self-free communication system (self-free communication network).

[0520] <6-1. Method 1> First, let me explain Method 1.

[0521] Figure 34A is a sequence diagram showing an example of the initial access processing according to the first method. Figure 34B shows the two base stations 20 (BS) shown in Figure 34A. １ and BS ２These are sequence diagrams rewritten based on the communication point reference. The control of the sequences shown in Figures 34A and 34B may be performed, for example, by the control units of each of the two BS (e.g., control unit 23) and the control unit of the UE (e.g., control unit 43). Alternatively, the control of the sequences shown in Figures 34A and 34B may be performed, for example, by the control units of each of the multiple communication points and the control unit of the UE.

[0522] In the following explanation, we may omit explanations of parts that overlap with other methods (methods 2 through 4). In other words, you may apply the content explained in other methods (methods 2 through 4) to method 1.

[0523] <6-1-1. Initial Access Processing> BS １ It transmits the first signal and / or the first broadcast information. １ It has one or more communication points (for example, communication point P １１ ~Communication points P １Ｎ ) may transmit the first signal and / or the first broadcast information. In this case, the first signal and / or the first broadcast information may be the on-demand first signal and / or the on-demand first broadcast information. In this case, one or more communication points may start transmitting the on-demand first signal and / or the on-demand first broadcast information in response to an initial trigger from a terminal device 40, before the UE starts the initial access process, for the initial access of a terminal device 40 different from the UE. The UE is BS １ The first signal and / or first broadcast information is received from.

[0524] Note: BS ２ However, the same on-demand first signal and / or on-demand first broadcast information may be transmitted. ２ , BS ２ A first signal and first broadcast information specific to BS may be transmitted. In this case as well, BS ２ It has one or more communication points (for example, communication point P2 １ ~Communication Point P2 Ｍ) may transmit the first signal and / or the first broadcast information. In this case, the first signal and / or the first broadcast information may be an on-demand first signal and / or on-demand first broadcast information.

[0525] BS １ and BS ２ Each communication point transmits a second signal. In this case, the second signal may be an on-demand second signal. The UE receives these second signals. Note that multiple second signals may be transmitted using different time and frequency resources. Alternatively, multiple second signals may be transmitted using code division multiplexing with the same time and frequency resources. At least from the UE's point of view, it is preferable that each second signal be received as a separate signal.

[0526] The UE performs initial access based on at least one of the first signal, the first broadcast information, and the second signal. In the first method, the UE, BS １ Initial access shall be performed to BS. At this time, UE shall １ You may send an extension trigger in response. BS １ Upon receiving an extension trigger, the device may extend the transmission of at least one of the first signal, the second signal, and the first broadcast information.

[0527] Furthermore, the UE may recognize that it can perform initial access to an entity (e.g., base station 20 / communication point) associated with or based on the first signal and / or the first broadcast information. In that case, the UE may recognize that the first signal and / or the first broadcast information is BS １ It is not necessary to know whether the message is being sent from a specific source.

[0528] UE provides information regarding the quality of communication for one or more communication points to BS. １ This information may be transmitted, for example, in a random access message 3 (msg3(PUSCH)). The communication quality may be determined, for example, based on a second signal.

[0529] Furthermore, the information transmitted by the UE (information regarding communication quality) may include communication quality information for all received communication points. In other words, the transmitted information may include communication quality information determined based on a second signal associated with all communication points notified in the first broadcast information.

[0530] Of course, the information transmitted by the UE (information regarding communication quality) may be information regarding the communication quality for some communication points. In this case, the UE may select communication points with good communication quality (for example, communication points with high RSRP values) and transmit information regarding the communication quality for the selected communication points in message 3 (msg3). At this time, the UE may select a predetermined number of communication points with good communication quality. The information for the predetermined number may be included in the first broadcast information. The predetermined number may also be predetermined. For example, the predetermined number is 1. The UE may also select communication points whose communication quality is above a predetermined threshold. The information for the predetermined threshold may be included in the first broadcast information.

[0531] The UE transmits information regarding the relative characteristics between communication points (relative information). This information may be transmitted, for example, in message 3 (msg3). The relative characteristics may be determined based on a second signal. The relative information (information regarding the relative characteristics between communication points) may be transmitted in addition to information regarding communication quality (information regarding the communication quality for each communication point), or it may be transmitted on its own.

[0532] In relative information, the reference communication point may be set or defined in advance, or it may be determined by a predetermined standard.

[0533] The relative information transmitted by the UE, like the information regarding communication quality, may be information relating to all received communication points, or it may be information relating to only some of those communication points. When relative information and information regarding communication quality are transmitted, the communication points corresponding to the relative information may be all of the communication points corresponding to the information regarding communication quality, or the communication points corresponding to the relative information may be some of the communication points corresponding to the information regarding communication quality.

[0534] After the initial access is complete, UE will use BS. １ A stop trigger may be sent in response. BS １ Upon receiving a stop trigger, the device may stop transmitting at least one of the first signal, the second signal, and the first broadcast information.

[0535] <6-1-2. Effects of the First Method> By using the first method, the base station 20 (and / or core network CN) can select a suitable communication point (e.g., an antenna) for the UE during the initial access process.

[0536] Furthermore, even if the base station 20 has multiple communication points (e.g., antennas), the UE does not need to know which communication point (e.g., antenna) is receiving initial access control, at least at the time of initial access processing. This can reduce the processing load on the UE.

[0537] Furthermore, the network side, including the base station 20 and the core network CN, can limit the entities that perform initial access control from the UE (e.g., base station 20 / communication point) to entities that transmit the first signal and the first broadcast information. Therefore, centralized processing can be performed, at least with respect to initial access control. For example, the network side can use entities with lower processing capacity than those that perform initial access control. As a result, costs can be reduced.

[0538] <6-2. Second Method> Next, the second method will be explained.

[0539] Figure 35A is a sequence diagram showing an example of the initial access processing according to the second method. Figure 35B shows the two base stations 20 (BS) shown in Figure 35A. １ and BS ２ These are sequence diagrams rewritten based on the communication point reference. The control of the sequences shown in Figures 35A and 35B may be performed, for example, by the control units of each of the two communication points (e.g., control unit 23) and the control unit of the UE (e.g., control unit 43). Alternatively, the control of the sequences shown in Figures 35A and 35B may be performed, for example, by the control units of each of the multiple communication points and the control unit of the UE.

[0540] In the following explanation, we may omit explanations of parts that overlap with other methods (the first method, the third method, and the fourth method). In other words, the content explained in the other methods (the first method, the third method, and the fourth method) may be applied to the second method.

[0541] <6-2-1. Selection of Communication Point> In the second method, the UE selects one communication point to connect to from among multiple communication points. For example, the UE selects one communication point to connect to based on the second signal received from each of the multiple communication points. Communication quality may be used as the selection criterion. In the examples of Figures 35A and 35B, the UE selects communication point P as the communication point to connect to. ２２ You have selected this option.

[0542] <6-2-2. Connection to the Selected Communication Point> The UE performs initial access to the selected communication point. In other words, the UE performs initial access based on the parameters associated with the selected communication point. The UE may also perform initial access based on the second signal of the selected communication point.

[0543] For example, the UE may determine the message 1 (msg1) to send based on the selected communication point. For example, the UE may select a preamble and / or determine the transmission resources for the preamble based on the selected communication point.

[0544] Information regarding initial access specific to a communication point may be included in the first broadcast information. As described above, the first broadcast information may also be on-demand first broadcast information.

[0545] Upon initial access, the UE may directly or indirectly transmit an extension trigger to the selected communication point. Upon receiving the extension trigger, the communication point may extend the transmission of at least one of the first signal, the second signal, and the first broadcast information.

[0546] The UE transmits information regarding the communication quality of the selected communication point to the selected communication point (or the base station 20 controlling the selected communication point). This information may be transmitted, for example, as a random access message 3 (msg3(PUSCH)). If the message 1 (msg1) to be transmitted is determined based on the selected communication point, the UE may include information indicating the selected communication point in message 1 (msg1). Of course, the UE may also notify the communication point (or base station 20) again of the information indicating the selected communication point. The UE may also include information regarding the communication quality of communication points other than the selected communication point in message 3 (msg3(PUSCH)). In this case, the selection of the communication point does not necessarily have to be done in the manner described above. Other methods (for example, the third method or the fourth method) may be used as methods for selecting the communication point.

[0547] The UE transmits information regarding the relative characteristics between communication points (relative information) to the selected communication point (or the base station 20 controlling the selected communication point). The relative information may be transmitted, for example, as a random access message 3 (msg3(PUSCH)).

[0548] The relative information transmitted includes, at a minimum, information regarding the relative characteristics between the selected communication point and other communication points. The selected communication point may also be the reference communication point for the relative information.

[0549] After the initial access is complete, the UE will access the selected communication point (for example, communication point P).２２ A stop trigger may be sent to the communication point. Upon receiving the stop trigger, the communication point may stop transmitting at least one of the first signal, the second signal, and the first broadcast information.

[0550] <6-2-3. Effects of the Second Method> By using the second method, the BS (and / or core network CN) can select a suitable communication point (e.g., an antenna) for the UE during the initial access process.

[0551] Furthermore, in the second method, the UE performs initial access control to a suitable antenna (communication point). Therefore, the time required for initial access processing (i.e., delay time) can be reduced compared to the conventional method.

[0552] Furthermore, the network side, including the base station 20 and the core network CN, can have different entities (e.g., BS / communication points) for each UE perform initial access control. Therefore, processing can be distributed, at least with respect to initial access control.

[0553] Furthermore, in the second method, the UE performs initial access control for a single communication point, even if there are multiple suitable communication points. The network side does not need to perform coordinated control between multiple communication points. As a result, the processing load can be reduced.

[0554] <6-3. The Third Method> Next, I will explain the third method.

[0555] Figure 36A is a sequence diagram showing an example of the initial access processing according to the third method. Figure 36B shows the two base stations 20 (BS) shown in Figure 36A. １ and BS ２ These are sequence diagrams rewritten based on the communication point reference. The control of the sequences shown in Figures 36A and 36B may be performed, for example, by the control units of each of the two BS (e.g., control unit 23) and the control unit of the UE (e.g., control unit 43). Alternatively, the control of the sequences shown in Figures 36A and 36B may be performed, for example, by the control units of each of the multiple communication points and the control unit of the UE.

[0556] In the following description, the description of the parts overlapping with other methods (the first method, the second method, and the fourth method) may be omitted. That is, the content described in other methods (the first method, the second method, and the fourth method) may be applied to the third method.

[0557] <6-3-1. Selection of Communication Points> In the third method, the UE selects one or more communication points to connect from among a plurality of communication points. For example, the UE selects one or more communication points to connect based on the second signals received from each of the plurality of communication points. Communication quality may be used as a selection criterion. In the examples of FIGS. 36A and 36B, the UE selects three communication points (communication point P １２ , communication point P ２１ , and communication point P ２４ ) as the communication points to connect.

[0558] The combination of selectable communication points, or the number of selectable communication points (for example, the maximum number and / or the minimum number) may be defined in advance. Alternatively, the UE may set the combination of selectable communication points, or the number of selectable communication points (for example, the maximum number and / or the minimum number) from another entity (for example, the base station 20 / communication point). The information on the combination may be included in the first notification information. As described above, the first notification information may be on-demand first notification information.

[0559] <6-3-2. Connection to the Selected Communication Points> The UE performs an initial access to the selected one or more communication points. In other words, the UE performs an initial access based on the combination of the selected communication points, or the parameters associated with one of the selected communication points. Also, the UE may perform an initial access based on the combination of the second signals of the selected communication points, or the second signal for one of the selected communication points.

[0560] For example, the UE may determine the message 1 (msg1) to send based on a combination of selected communication points, or on one of the selected communication points. For example, the UE may select a preamble and / or determine the transmission resources of the preamble based on a combination of selected communication points, or on one of the selected communication points. Alternatively, the UE may determine the transmission resources (RACH resources) of the preamble based on one of the selected communication points, and select the preamble based on each of the selected communication points.

[0561] Information regarding initial access specific to a communication point or combination of communication points may be included in the first broadcast information. As described above, the first broadcast information may also be on-demand first broadcast information.

[0562] Upon initial access, the UE may directly or indirectly transmit an extension trigger to one or more selected communication points. Upon receiving the extension trigger, a communication point may extend the transmission of at least one of the first signal, the second signal, and the first broadcast information.

[0563] The UE transmits information regarding the communication quality of the selected communication point to the selected communication point (or the base station 20 controlling the selected communication point). This information may be transmitted, for example, as a random access message 3 (msg3(PUSCH)).

[0564] If multiple communication points are selected, the UE may transmit individual information corresponding to each of the multiple communication points as information regarding communication quality. Alternatively, the UE may transmit a single piece of information corresponding to multiple communication points as information regarding communication quality.

[0565] When UE transmits one piece of information (information relating to communication quality) corresponding to multiple communication points in message 3, the information transmitted (information relating to communication quality) may be at least one of the pieces of information shown in (L1) to (L2) below.

[0566] (L1) Communication quality information after synthesizing a second signal associated with multiple communication points. For example, the information regarding communication quality may be information determined based on the sum of the RSRP values ​​of each of the multiple communication points.

[0567] (L2) Communication quality information determined based on the communication quality value (at least one of the maximum value, minimum value, average value, and median value) of each of the multiple communication points. For example, the information regarding communication quality may be information determined based on the RSRP value (at least one of the maximum value, minimum value, average value, and median value) of each of the multiple communication points.

[0568] If message 1 (msg1) is determined based on the selected combination of communication points, the UE may include information indicating the selected communication points in message 1 (msg1). Of course, the UE may also notify the communication points (or base station 20) again of the information indicating the selected communication points. The UE may also include information regarding the communication quality of communication points other than the selected communication points in message 3 (msg3 (PUSCH)). In this case, the selection of communication points does not necessarily have to be done in the manner described above. Other methods (for example, the second method or the fourth method) may be used as methods for selecting communication points.

[0569] The UE transmits information regarding the relative characteristics between communication points (relative information) to one or more selected communication points (or the base station 20 controlling one or more selected communication points). The relative information may be transmitted, for example, as a random access message 3 (msg3(PUSCH)).

[0570] The transmitted relative information includes information about the relative characteristics between at least one of the selected communication points and the other communication points. If multiple communication points are selected, one of the selected communication points may be the reference communication point for the relative information.

[0571] After the initial access is complete, the UE will access the selected communication point (for example, communication point P). １２Communication point P ２１ , and communication point P ２４ A stop trigger may be sent to at least one of the following: , . When a communication point receives a stop trigger, it may stop transmitting at least one of the first signal, the second signal, and the first broadcast information.

[0572] <6-3-3. Effects of the Third Method> By using the third method, the BS (and / or core network CN) can select a suitable communication point (e.g., an antenna) for the UE during the initial access process.

[0573] Furthermore, in the third method, the UE performs initial access control to a suitable antenna (communication point). Therefore, the time required for initial access processing (i.e., delay time) can be reduced compared to the conventional method.

[0574] Furthermore, the network side, including the BS and core network CN, can have different entities (e.g., BS / communication points) for each UE that perform initial access control from the UE. Therefore, processing can be distributed, at least with regard to initial access control.

[0575] Furthermore, in the third method, the UE performs initial access control for a single communication point, even if there are multiple suitable communication points. The network side does not need to perform coordinated control between multiple communication points. As a result, the overhead of control information can be reduced. In addition, the delay related to that control can be reduced.

[0576] <6-4. The Fourth Method> Next, the fourth method will be explained.

[0577] Figure 37A is a sequence diagram showing an example of the initial access processing according to the fourth method. Figure 37B shows the two base stations 20 (BS) shown in Figure 37A. １ and BS ２It is a sequence diagram in which ( ) is rewritten based on the communication point reference respectively. The control of the sequence shown in FIGS. 37A and 37B may be performed by, for example, the control units (e.g., control unit 23) of each of the two BSs and the control unit (e.g., control unit 43) of the UE. Alternatively, the control of the sequence shown in FIGS. 37A and 37B may be performed by, for example, the control units of each of the plurality of communication points and the control unit of the UE.

[0578] In the following description, the description of the parts overlapping with other methods (the first method to the third method) may be omitted. That is, the content described in other methods (the first method to the third method) may be applied to the fourth method.

[0579] <6-4-1. Two-stage random access> In the fourth method, random access is performed in two stages. In the following description, the first stage of the random access performed in two stages is referred to as the first random access, and the second stage is referred to as the second random access.

[0580] In the fourth method, the BS １ (communication point P １１ to communication point P １Ｎ ) repeatedly (e.g., periodically) transmits the first signal and / or the first notification information. The first signal may be an on-demand first signal or may not be an on-demand first signal. That is, the first signal may be a signal that is repeatedly (e.g., periodically) transmitted in response to a request, or may be a signal that is repeatedly (e.g., periodically) transmitted continuously without depending on a request. Similarly, the first notification information may be on-demand first notification information or may not be on-demand first notification information. That is, the first notification information may be information transmitted in response to a request, or may be information that is repeatedly (e.g., periodically) transmitted continuously without depending on a request.

[0581] Also, in the fourth method, the BS １ (communication point P １１ to communication point P １Ｎ ), and the BS ２ (communication point P ２１~Communication points P ２Ｍ A second signal and / or second broadcast information is transmitted from at least one entity (base station 20 / communication point) among the ),. The second broadcast information is, for example, transmitted by UE, BS ２ (Communication point P) ２１ ~Communication points P ２Ｍ This information is for performing at least one of the following: performing initial access to the first signal, and receiving the second signal. In addition, the content of the second broadcast information may be the same as that of the first broadcast information.

[0582] Here, the second signal may be a signal transmitted on request, or a signal transmitted without request. In other words, the second signal may be an on-demand second signal. Similarly, the second broadcast information may be a signal transmitted on request, or a signal transmitted without request. In other words, the second broadcast information may be an on-demand second broadcast information.

[0583] In this case, the second signal may or may not be a signal that is transmitted repeatedly. For example, the second signal may be a signal that is transmitted periodically, or a signal that is transmitted only once when a condition is met (for example, a signal that is transmitted only once upon request). Similarly, the second broadcast information may or may not be information that is transmitted repeatedly. For example, the second broadcast information may be information that is transmitted periodically, or a signal that is transmitted only once when a condition is met (for example, a signal that is transmitted only once upon request).

[0584] When transmitted repeatedly (for example, periodically), information relating to the second signal and / or the second broadcast information may be included in the first broadcast information. Alternatively, when transmitted periodically, information relating to the second signal and / or the second broadcast information may be included as described below, BS １ (or, communication point P) １１ ~Communication points P １Ｎ It may be included in message 2 (msg2a) from at least one of the following.

[0585] If transmitted only once when the conditions are met (for example, transmitted only once upon request), the information relating to t...

Claims

A transmission control unit that transmits a trigger signal to a communication point performing a repeat transmission that is initiated on demand, for the purpose of extending or stopping the repeat transmission of at least one of a first signal and a first broadcast information. A communication device equipped with the following features. 　 The communication device is a terminal device that receives at least one of the first signal and the first notification information. The communication device according to claim 1. 　 The communication device is a second terminal device which is the same as or different from the first terminal device which transmits the initial trigger for initiating the repeated transmission. The transmission control unit transmits the trigger signal to the communication point when predetermined conditions are met. The communication device according to claim 2. 　 When the predetermined conditions are met, the transmission control unit transmits an extension trigger signal as the trigger signal to extend the repeated transmission. The aforementioned predetermined conditions include the fact that the present time is a predetermined period before the end of the repeated transmission, or a predetermined number of times before the final transmission of the repeated transmission. The communication device according to claim 3. 　 The communication point is configured to go into sleep mode or power off after the execution period of the repeated transmission has elapsed. The trigger signal is transmitted to the communication point via another communication point different from the communication point. The predetermined conditions include that the trigger signal reaches the communication point before the communication point goes into sleep mode or is powered off. The communication device according to claim 3. 　 Another communication point, different from the aforementioned communication point, sends an initial trigger to the aforementioned communication point to initiate the repeated transmission. The transmission control unit, when certain conditions are met, transmits the trigger signal to the communication point to extend or stop the repeated transmission that was started by the initial trigger transmitted by the other communication point. The communication device according to claim 2. 　 The aforementioned predetermined conditions include receiving a predetermined notification from the other communication point. The communication device according to claim 6. 　 The communication device is the same terminal device as the terminal device that transmits the initial trigger for initiating the repeated transmission. The transmission control unit, when certain conditions are met, transmits the trigger signal to the communication point to extend or stop the repeated transmission that was started by the initial trigger it transmitted. The communication device according to claim 2. 　 The first signal and the first broadcast information include information regarding the execution period of the repeated transmission, The transmission control unit makes a determination regarding the transmission of the trigger signal based on information regarding the execution period of the repeated transmission. The communication device according to claim 2. 　 The communication point is configured to go into sleep mode or power off after the execution period of the repeated transmission has elapsed. At least one of the first signal and the first notification information includes information regarding the time from the end of the repeated transmission until the communication point goes to sleep or is powered off. The transmission control unit makes a determination regarding the transmission of the trigger signal based on information regarding the time from the end of the repeated transmission until the communication point goes to sleep or is powered off. The communication device according to claim 2. 　 The first signal and at least one of the first notification information include information regarding the configuration of the trigger signal, The transmission control unit transmits the trigger signal based on information regarding the configuration of the trigger signal. The communication device according to claim 2. 　 The aforementioned communication device is a different communication point from the aforementioned communication point. The transmission control unit transmits the trigger signal to the communication point when predetermined conditions are met. The communication device according to claim 1. 　 The aforementioned communication point is a communication node that constitutes a self-free communication network, The first signal and the first notification information are signals or information used during initial access to the self-free communication network. The communication device according to claim 1. When a second terminal device makes an initial access to the communication point where the first terminal device has already started the repeated transmission for initial access, the transmission control unit transmits an extension trigger signal as the trigger signal to extend the repeated transmission. The communication device according to claim 13. 　 A base station that controls a communication point, which is a repeating transmission initiated on demand and which performs the repeating transmission of at least one of a first signal and first broadcast information, A receiving control unit that receives a trigger signal to extend or stop the repeated transmission, A transmission control unit that, upon receiving the trigger signal, extends or stops the repeated transmission, A base station equipped with the necessary equipment. 　 The receiving control unit receives an extension trigger signal for extending the repeated transmission as the trigger signal, The transmission control unit extends the repeated transmission until an end timing determined starting from the timing of receiving the extension trigger signal. The base station according to claim 15. 　 The trigger signal includes information regarding the extension time of the repeated transmission, or information regarding the stop time of the repeated transmission. The transmission control unit extends or stops the repeated transmission based on the information contained in the trigger signal. The base station according to claim 15. 　 The receiving control unit receives an extension trigger signal for extending the repeated transmission as the trigger signal, The extension trigger signal includes information regarding the extension time of the repeated transmission. The transmission control unit extends the repeated transmission until an end timing determined based on information regarding the extension time of the repeated transmission. The base station according to claim 17. 　 A repeating transmission initiated on demand, wherein a trigger signal is transmitted to a communication point performing the repeating transmission of at least one of a first signal and first broadcast information, to cause the repeating transmission to be extended or stopped. Communication method. 　 A repeating transmission initiated on demand, which receives a trigger signal to extend or stop the repeating transmission of at least one of a first signal and a first broadcast information. When the trigger signal is received, the repeated transmission is extended or stopped. Communication method.

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