Propagation path control device, control device, and control method

Abstract

This propagation path control device has a structure that reflects or transmits arriving radio waves, and is capable of controlling the reflection characteristics or transmission characteristics of the structure. The propagation path control device comprises: a determination unit that determines a schedule for forming a plurality of reflection patterns or a plurality of transmission patterns corresponding to a plurality of communication devices that perform wireless communication; and a propagation path control unit that repeatedly executes the schedule.

Description

Propagation path control device, control device, and control method

[0001] The present disclosure relates to a propagation path control device, a control device, and a control method.

[0002] As communication demand expands, the depletion of radio wave resources (wireless resources) has become a problem. To address this issue, attention has been focused on technologies that improve frequency utilization efficiency by dynamically changing radio wave propagation paths (channels). Reconfigurable intelligent surfaces (RISs) are known as devices for changing propagation paths (hereinafter also referred to as propagation path control devices). RISs are classified into two types: RISs that operate in cooperation with communication devices such as base stations (referred to as cooperative RISs in this embodiment), and RISs that operate independently of communication devices (referred to as blind RISs in this embodiment). The installation of RISs makes it possible, for example, to control the reflection direction of radio waves and form new propagation paths.

[0003] International Publication No. 2023 / 145031

[0004] However, simply introducing a RIS may not fully realize effective use of radio wave resources. For example, assume that a base station and multiple terminal devices communicating with the base station exist in an environment where a RIS is installed. In this case, for the RIS to support multiple terminal devices, it is desirable for the RIS to appropriately control the reflection pattern or transmission pattern based on a schedule defined by the base station. However, in an environment where a Blind RIS is used as the RIS, it is difficult for the RIS to obtain schedule information from the base station. In this case, it is difficult for the RIS to switch the reflection pattern or transmission pattern based on the schedule of each terminal device, so there is a possibility that effective use of radio wave resources may not be fully realized.

[0005] Therefore, the present disclosure proposes a propagation path control device, a control device, and a control method that can realize effective use of radio wave resources.

[0006] It should be noted that the above problem or object is merely one of multiple problems or objects that can be solved or achieved by multiple embodiments disclosed in this specification.

[0007] In order to solve the above problems, one form of propagation path control device according to the present disclosure is a propagation path control device that has a structure that reflects or transmits incoming radio waves and is capable of controlling the reflection characteristics or transmission characteristics of the structure, and is equipped with a determination unit that determines a schedule for forming multiple reflection patterns or multiple transmission patterns corresponding to multiple communication devices that perform wireless communication, and a propagation path control unit that repeatedly executes the schedule.

[0008] 1 is a diagram for explaining the structure of a RIS. FIG. 1 is a diagram illustrating a state in which a RIS is installed in an environment where a base station and a plurality of terminal devices exist. FIG. 2 is a diagram illustrating an example of allocation of formation times of reflection patterns or transmission patterns. FIG. 3 is a diagram illustrating a configuration of a communication system according to the present embodiment. FIG. 4 is a diagram illustrating a configuration of a communication system according to the present embodiment. FIG. 5 is a diagram illustrating a configuration of a management device according to the present embodiment. FIG. 6 is a diagram illustrating a configuration of a base station according to the present embodiment. FIG. 7 is a diagram illustrating an example configuration of a propagation path control device according to an embodiment of the present disclosure. FIG. 8 is a diagram illustrating a configuration of a terminal device according to the present embodiment. FIG. 9 is a diagram illustrating an example configuration of a control station according to an embodiment of the present disclosure. FIG. 10 is a diagram illustrating an example of a communication environment assumed in Example 1. FIG. 11 is a sequence diagram illustrating communication processing according to Example 1. FIG. 12 is a flowchart illustrating an example of a determination processing. FIG. 13 is a flowchart illustrating another example of the determination processing. FIG. 14 is a diagram illustrating an example allocation of formation times of reflection patterns or transmission patterns. FIG. 15 is a diagram illustrating an example allocation of formation times of reflection patterns or transmission patterns. FIG. 16 is a diagram illustrating an example of allocation of formation times of reflection patterns or transmission patterns.

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the following embodiments, the same components are designated by the same reference numerals, and redundant description will be omitted.

[0010] Additionally, in this description / specification, the phrase "at least one of" following a list of elements is understood to mean that the listed elements are optional. 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., words, phrases, clauses, terms, or items).

[0011] In addition, in this specification and drawings, multiple components having substantially the same functional configuration may be distinguished by adding different numbers to the same reference numeral. For example, multiple components having substantially the same functional configuration may be distinguished by adding different numbers to the same reference numerals to the propagation path control device 30 as needed. １ , 30 ２ , and 30 ３ However, when there is no need to particularly distinguish between a plurality of components having substantially the same functional configuration, only the same reference numerals are used. For example, the propagation path control device 30 １ , 30 ２ , and 30 ３ When there is no need to particularly distinguish between them, they will be simply referred to as the propagation path control device 30.

[0012] One or more embodiments (including examples and variations) described below can be implemented independently. However, at least a portion of the embodiments described below may be implemented in appropriate combination with at least a portion of another embodiment. These embodiments may include novel features that are different from one another. Therefore, these embodiments may contribute to solving different purposes or problems and may produce different effects.

[0013] The present disclosure will be described in the following order: 1. Overview 1-1. Problem 1-2. Overview of the solution 2. Configuration of the communication system 2-1. Configuration of the management device 2-2. Configuration of the base station 2-3. Configuration of the propagation path control device 2-4. Configuration of the terminal device 2-5. Configuration of the control station 3. Operation of the communication system 3-1. Normal operation of the RIS 3-2. Example 1 3-3. Example 2 4. Modification 5. Conclusion

[0014] <<1. Overview>> As demand for communications expands, the problem of radio wave resources (wireless resources) becoming depleted has become apparent. To address this problem, attention has been focused on technologies that improve frequency utilization efficiency by dynamically changing radio wave propagation paths. A known device for changing propagation paths (hereinafter also referred to as a propagation path control device) is a reconfigurable intelligent surface (RIS). A RIS is also called an intelligent reflecting surface (IRS) or an intelligent surface (IS).

[0015] FIG. 1 is a diagram illustrating the structure of a RIS. A RIS is a device including a structure (e.g., a reflector) composed of one or more metasurface elements whose permittivity and / or permeability can be dynamically controlled. A metasurface element is a type of artificial medium (metamaterial) that achieves any permittivity and / or permeability by periodically arranging structures that are small relative to the wavelength. A metasurface element is sometimes simply referred to as a metasurface. A RIS can control the amplitude, phase, polarization, or frequency of an incoming radio wave by manipulating the permittivity and / or permeability of the metasurface (metasurface element). A control device inside or outside the RIS can control the direction of the reflected wave to bypass an obstruction or form a new propagation path by controlling the reflected wave from the RIS.

[0016] There are two types of RIS: a RIS that operates in cooperation with communication devices such as base stations (referred to as Cooperative RIS in this embodiment), and a RIS that operates without cooperation with communication devices (referred to as Blind RIS in this embodiment). Blind RIS does not require the development of infrastructure for cooperation with a transceiver. Therefore, Blind RIS has the advantage of high installation flexibility. On the other hand, Blind RIS cannot cooperate with communication devices that perform wireless communication. Therefore, compared to Cooperative RIS, Blind RIS has the problem that its ability to improve the propagation environment depends on the information gathering ability of the RIS.

[0017] <1-1. Issues> The introduction of RIS is expected to improve frequency utilization efficiency. However, simply introducing RIS may not fully realize effective utilization of radio wave resources.

[0018] For example, assume that a base station and a plurality of terminal devices that communicate with the base station exist in an environment where a RIS is installed. Figure 2 is a diagram showing a state in which a RIS is installed in an environment where a base station (BS) and a plurality of terminal devices (UE#1 to UE#4) exist. In the example of Figure 2, one RIS is installed in an environment where one base station (BS) and four terminal devices (UE#1 to UE#4) exist. Note that multiple RISs may be installed.

[0019] In this case, in order for the RIS to support multiple terminal devices, it is desirable for the RIS to appropriately control the reflection pattern or transmission pattern based on a schedule defined by the base station. In the example of Figure 2, it is desirable for the RIS to appropriately change the reflection direction of radio waves depending on which of UE #1 to UE #4 the BS is currently communicating with.

[0020] However, in an environment where a blind RIS is used, it is difficult for the RIS to obtain schedule information from the base station, and in this case, it is difficult for the RIS to appropriately switch between reflection and transmission patterns based on the schedule of each terminal device, which may result in insufficient effective use of radio wave resources.

[0021] <1-2. Overview of Solution> Therefore, in this embodiment, the above-mentioned problems are solved as follows.

[0022] The communication system of this embodiment includes a plurality of communication devices (for example, base stations and / or terminal devices) and a plurality of RISs, as shown in Fig. 2. In the example of Fig. 2, the communication system includes one base station (BS) and three terminal devices (UE#1 to UE#4). Here, the RIS is a blind RIS, and is not connected to the base station.

[0023] First, the RIS determines the communication devices to be controlled for the propagation path. For example, the RIS determines the communication devices to be controlled for the propagation path based on whether or not there is a line of site (LOS) between the RIS and the communication device. In the example of FIG. 2, there is a line of site (LOS) between the RIS and UE #1 to UE #3, but there is no LOS between the RIS and UE #4. Therefore, the RIS determines that UE #1 to UE #3 are terminal devices to be controlled. A sensor such as a camera may be used to determine whether or not there is a line of site (LOS).

[0024] It is also possible that the RIS and the base station are installed in fixed locations, and the RIS knows the location of the base station in advance. In this case, the RIS can determine that the base station is a communication device whose propagation path is to be controlled without determining whether or not it is in LOS. However, if the locations of the RIS and the base station are not known in advance (for example, if at least one of the RIS and the base station is mobile), the RIS may determine whether or not the base station is a communication device whose propagation path is to be controlled (for example, whether or not there is LOS between the RIS and the base station). Of course, even if both the RIS and the base station are not mobile, the RIS may determine whether or not the base station is a communication device whose propagation path is to be controlled.

[0025] The RIS then determines a schedule for forming a plurality of reflection patterns or a plurality of transmission patterns corresponding to a plurality of communication devices to be controlled on the propagation path. In the example of Figure 2, the RIS determines a schedule for forming three reflection patterns or three transmission patterns corresponding to three terminal devices UE#1 to UE#3.

[0026] Here, the reflection pattern is a pattern related to the reflection of an incoming radio wave (for example, a conversion pattern of an incoming wave, or a formation / generation pattern of a reflected wave). For example, the reflection pattern is a combination of configurations of a metasurface (metasurface element). Here, the configuration may be setting information for forming / generating a reflected wave for each metasurface (for example, information related to permittivity and / or permeability). Note that the reflection pattern may also be a waveform pattern of a reflected wave formed by a combination of the configurations. In this embodiment, the formation of a reflection pattern may refer to the RIS changing the permittivity and / or permeability of one or more metasurfaces (metasurface elements), for example, to achieve the intended reflection characteristics.

[0027] Furthermore, the transmission pattern is a pattern related to the transmission of the incoming radio waves (for example, a conversion pattern of the incoming wave or a formation / generation pattern of the transmitted wave). For example, the transmission pattern is a combination of configurations of metasurfaces (metasurface elements). Here, the configuration may be setting information for the formation / generation of the transmitted wave for each metasurface (for example, information related to the permittivity and / or permeability). Note that the transmission pattern may also be a waveform pattern of the transmitted wave formed by the combination of the configurations. In this embodiment, the formation of a transmission pattern may refer to the RIS changing the permittivity and / or permeability of one or more metasurfaces (metasurface elements), for example, to achieve the intended transmission characteristics.

[0028] The RIS may determine a schedule by allocating reflection pattern or transmission pattern formation times to multiple communication devices based on a predetermined rule. For example, the RIS may allocate reflection pattern or transmission pattern formation times to multiple communication devices based on the PF (Proportional Fair) rule (also referred to as Proportional Fair Scheduling or Proportional Fair Sharing). FIG. 3 is a diagram showing an example of allocation of reflection pattern or transmission pattern formation times. In the example of FIG. 3, the RIS allocates reflection pattern or transmission pattern formation times to three terminal devices UE#1 to UE#3 for a time period of length P1. More specifically, the RIS allocates reflection pattern or transmission pattern formation times to UE#1, UE#3, and UE#2 in a ratio of 3:1:2.

[0029] In this case, the unit of allocation of the formation time of the reflection pattern or transmission pattern (r1 shown in FIG. 3) may be the slot length, or may be the same time length as the Rank Index feedback period in MIMO communication, or may be the same time length as the MCS change interval.

[0030] Once the schedule is determined, the RIS repeatedly executes the schedule. In the example of Figure 3, the RIS repeatedly executes a schedule with a length of P1.

[0031] This allows a good propagation path to be formed for a specific terminal device at a specific timing in a specific cycle. As a result, the base station determines a communication schedule (e.g., an uplink, downlink, and / or sidelink schedule) with the terminal device so as to communicate with the terminal device at that timing. In other words, the RIS schedule is reflected in the base station's communication schedule in an autonomous and distributed manner. As a result, the RIS can switch between a reflection pattern and a transmission pattern according to the communication schedule of each terminal device, thereby achieving effective use of radio wave resources.

[0032] The outline of this embodiment has been described above, and the communication system 1 of this embodiment will now be described in detail.

[0033] <<2. Configuration of the Communication System>> First, the configuration of the communication system 1 will be specifically described. Figures 4 and 5 are diagrams showing the configuration of the communication system 1 according to this embodiment. As shown in Figure 4, the communication system 1 includes a management device 10, a base station 20, a propagation path control device 30, and a terminal device 40. Note that the communication system 1 may include devices other than those shown in Figure 4. For example, as shown in Figure 5, the communication system 1 may include a control station 50 that controls multiple propagation path control devices 30. Of course, the communication system 1 may not include some of the devices shown in Figures 4 and 5.

[0034] The communication system 1 provides a wireless network (mobile network) that enables mobile communication for users by the cooperation of the wireless communication devices that make up the communication system 1. The wireless network of this embodiment may be, for example, a cellular network that includes a radio access network RAN ​​and a core network CN. The mobile network may include a terminal device 40. In this embodiment, the wireless communication device is a communication device that has a wireless communication function, and in the example of FIG. 4, this corresponds to the base station 20 and the terminal device 40.

[0035] The communication system 1 may include a plurality of management devices 10, base stations 20, propagation path control devices 30, terminal devices 40, and control stations 50. In the example of FIG. 4, the communication system 1 includes a management device 10 １ and management device 10 ２ and the base station 20 is provided with １ , base station 20 ２ , and base station 20 ３ In the example of FIG. 4, the communication system 1 includes a propagation path control device 30. １ , propagation path control device 30 ２ , and the propagation path control device 30 ３ The terminal device 40 is provided with the terminal device 40 １ , terminal device 40 ２ , and terminal device 40 ３In the example of FIG. 5, the communication system 1 includes a control station 50. １ , and the control station 50 ２ The control station 50 that controls the plurality of propagation path control devices 30 may be one, or may be three or more.

[0036] The terminal device 40 may be configured to connect to a network using radio access technologies (RATs) such as LTE (Long Term Evolution), NR (New Radio), B5G (Beyond 5G), 6G, Wi-Fi, Bluetooth (registered trademark), etc. In this case, the terminal device 40 may be configured to be able to use different radio access technologies (wireless communication methods). For example, the terminal device 40 may be configured to be able to use NR and Wi-Fi. Furthermore, the terminal device 40 may be configured to be able to use different cellular 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).

[0037] LTE and NR are types of cellular communication technologies that enable mobile communication for terminal devices by arranging multiple areas covered by base stations in the form of cells. 6G, also a type of cellular communication technology, has the potential to become a technology that enables mobile communication for terminal devices by arranging multiple areas covered by base stations in the form of cells.

[0038] In the following description, "LTE" includes LTE-A (LTE-Advanced), LTE-A Pro (LTE-Advanced Pro), and EUTRA (Evolved Universal Terrestrial Radio Access). NR includes NRAT (New Radio Access Technology) and FEUTRA (Further EUTRA). A single base station 20 may manage multiple cells. In the following description, a cell corresponding to LTE is referred to as an LTE cell, and a cell corresponding to NR is referred to as an NR cell.

[0039] NR is the next generation (5th generation) radio access technology after LTE (4th generation communications including LTE-Advanced and LTE-Advanced Pro). NR is a radio 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 (registered trademark) Rel-15 as a technical framework that corresponds to the usage scenarios, requirements, and deployment scenarios of these use cases. Furthermore, B5G and 6G are required to simultaneously achieve multiple axes of high speed, large capacity, low latency, high reliability, and multiple simultaneous connections.

[0040] 6G is the next generation of cellular communication technology after NR (5th generation mobile communications) and 5GS (5G system). 6G includes radio access technology and network technology between base stations, core networks, and data networks. 6G also includes technologies for extreme connectivity of eMBB, mMTC, and URLLC, which were the main use cases or requirements of 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 (including radar sensing and network as a sensor), and terahertz communication.

[0041] The wireless network may support at least one of radio access technologies (RATs) such as LTE (Long Term Evolution), NR (New Radio), B5G, and 6G. LTE, NR, and 6G are types of cellular communication technologies that enable mobile communication for terminal devices by arranging multiple areas covered by base stations in the form of cells. The wireless access method used by the communication system 1 is not limited to LTE, NR, B5G, and 6G, and may be other wireless access methods such as W-CDMA (Wideband Code Division Multiple Access) and cdma2000 (Code Division Multiple Access 2000).

[0042] Furthermore, the base station 20 may be a terrestrial station or a non-terrestrial station. The non-terrestrial station may be a satellite station or an aircraft station. If the non-terrestrial station is a satellite station, the wireless network may be a bent-pipe (transparent) type mobile satellite communication system.

[0043] In this embodiment, terrestrial stations and terrestrial base stations refer to base stations and relay stations installed on the ground. Here, "terrestrial" refers to terrestrial in a broad sense, including not only land but also underground, on water, and underwater. In the following description, the term "terrestrial station" may be replaced with "gateway."

[0044] Note that an LTE base station may be referred to as an eNodeB (Evolved Node B) or eNB. An NR base station may be referred to as a gNodeB or gNB. A 6G base station may be referred to as a 6G NodeB (6GNB). In LTE, NR, and 6G, a terminal device (also referred to as a mobile station or terminal) may be referred to as a UE (User Equipment). Note that a terminal device is a type of communication device and is also referred to as a mobile station or terminal.

[0045] The terminal device 40 may be able to connect to a network using a wireless access technology (wireless communication method) other than LTE, NR, B5G, 6G, Wi-Fi, or Bluetooth. For example, the terminal device 40 may be able to connect to a network using low power wide area (LPWA) communication. The terminal device 40 may also be able to connect to a network using proprietary wireless communication.

[0046] Here, LPWA communication refers to wireless communication that enables low-power, wide-range communication. For example, LPWA wireless refers to IoT (Internet of Things) wireless communication using a specified low-power radio (e.g., the 920 MHz band) or the ISM (Industry-Science-Medical) band. Note that the LPWA communication used by the terminal device 40 may be compliant with the LPWA standard. Examples of LPWA standards include ELTRES, ZETA, SIGFOX, LoRaWAN, and NB-IoT. Of course, the LPWA standard is not limited to these, and other LPWA standards may also be used.

[0047] 4 and 5 may be considered as devices in a logical sense, that is, a part of each wireless communication device may be realized by a virtual machine (VM), a container such as Docker, or the like, and these may be physically implemented on the same hardware.

[0048] 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 in structures or mobile bodies. The structures or mobile bodies themselves may be considered wireless communication devices. Furthermore, the concept of a wireless communication device includes not only terminal devices 40 but also base stations 20. A wireless communication device is a type of processing device or information processing device. A wireless communication device can also be referred to as a transmitting device or a receiving device.

[0049] The following describes in detail the configuration of each communication device that constitutes the communication system 1. Note that the configuration of each communication device shown below is merely an example. The configuration of each communication device may be different from the configuration shown below.

[0050] 2-1. Configuration of Management Device First, the configuration of the management device 10 will be described.

[0051] The management device 10 is an information processing device (computer) that manages a wireless network. For example, the management device 10 is an information processing device that manages communications of the base station 20. The management device 10 is also a type of communication device.

[0052] The management device 10 may be, for example, a device having a function as an MME (Mobility Management Entity). The management device 10 may also be a device having a function 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 a core network. The management device 10 may be a device having a function as a control plane network function (6G CPNF) in 6G. The 6G CPNF may be composed of one or more logical nodes.

[0053] Of course, the functions of the management device 10 are not limited to MME, AMF, SMF, and 6G CPNF. The management device 10 may be a device having functions as a Network Slice Selection Function (NSSF), an Authentication Server Function (AUSF), a Policy Control Function (PCF), and a Unified Data Management (UDM). Furthermore, the management device 10 may be a device having functions as a Home Subscriber Server (HSS).

[0054] The management device 10 may have a gateway function. For example, the management device 10 may have a function as an S-GW (Serving Gateway) or a P-GW (Packet Data Network Gateway). The management device 10 may also have a UPF (User Plane Function) function. In this case, the management device 10 may have multiple UPFs. The management device 10 may also be a device that has a function as a 6G User Plane Network Function (6G UPNF).

[0055] The core network is composed of multiple network functions, and each network function may be consolidated into one physical device or distributed across multiple physical devices. In other words, the management device 10 may be distributed across multiple devices. Furthermore, this distributed distribution may be controlled so that it is executed dynamically. The base station 20 and the management device 10 form a single network, providing wireless communication services to terminal devices 40. The management device 10 is connected to the Internet, and the terminal devices 40 can use various services provided via the Internet via the base station 20.

[0056] The management device 10 does not necessarily have to be a device that constitutes a core network. For example, assume that the core network is a W-CDMA (Wideband Code Division Multiple Access) or cdma2000 (Code Division Multiple Access 2000) core network. In this case, the management device 10 may be a device that functions as an RNC (Radio Network Controller).

[0057] Fig. 6 is a diagram showing the configuration of the management device 10 according to this embodiment. The management device 10 includes a communication unit 11, a storage unit 12, and a control unit 13. The configuration shown in Fig. 6 is a functional configuration, and the hardware configuration may be different from this. Furthermore, the functions of the management device 10 may be statically or dynamically distributed and implemented in multiple physically separated configurations. The management device 10 may also be configured by multiple server devices.

[0058] The communication unit 11 is a communication interface for communicating with other communication devices (e.g., the base station 20). The communication unit 11 may be a network interface or a device connection interface. The communication unit 11 may be a LAN (Local Area Network) interface such as a NIC (Network Interface Card), or a USB (Universal Serial Bus) interface configured by a USB host controller or a USB port. The communication unit 11 may be a wired interface or a wireless interface. The communication unit 11 functions as a communication means of the management device 10. The communication unit 11 is controlled by the control unit 13.

[0059] The storage unit 12 is a readable and writable storage device such as a dynamic random access memory (DRAM), a static random access memory (SRAM), a flash memory, or a hard disk. The storage unit 12 functions as a storage means of the management device 10. The storage unit 12 stores, for example, the connection status of the terminal device 40. The storage unit 12 stores the status of the radio resource control (RRC) of the terminal device 40 and the status of the EPS connection management (ECM) or the 5G system connection management (CM). The storage unit 12 may function as a home memory that stores location information of the terminal device 40. The storage unit 12 also stores a learning model (prediction model) for predicting the future quality of the mobile network. The learning model will be described later.

[0060] The control unit 13 is a controller that controls each component of the management device 10. The control unit 13 may be implemented by a processor such as a central processing unit (CPU) or a microprocessing unit (MPU). Specifically, the control unit 13 may be implemented by a processor executing various programs stored in a storage device internal to the management device 10 using a random access memory (RAM) or the like as a work area. The control unit 13 may be implemented by an integrated circuit such as an application-specific integrated circuit (ASIC) or a field programmable gate array (FPGA). The control unit 13 may also be implemented by a graphics processing unit (GPU). A CPU, an MPU, an ASIC, an FPGA, and a GPU can all be considered controllers. The control unit 13 may be configured by multiple physically separated entities. For example, the control unit 13 may be configured by multiple semiconductor chips.

[0061] The operation of the control unit 13 may be similar to the operation of each block included in the control unit 33 of the propagation path control device 30, or may be similar to the operation of each block included in the control unit 53 of the control station 50. The operation of the control unit 13 may also be similar to the operation of the control unit 23 of the base station 20, or may be similar to the operation of the control unit 43 of the terminal device 40.

[0062] <2-2. Configuration of Base Station> Next, the configuration of the base station 20 will be described.

[0063] The base station 20 is a wireless communication device that performs wireless communication with other wireless communication devices (for example, a terminal device 40 or another base station 20). The base station 20 may perform wireless communication with the terminal device 40 via a relay station, or may perform wireless communication directly with the terminal device 40. In the following description, the base station 20 may be referred to as a BS 20.

[0064] The base station 20 is a device equivalent to a radio base station (e.g., base station, Node B, eNB, gNB, or 6GNB) or a radio access point. The base station 20 may be a radio relay station. The base station 20 may be an optical device called an RRH (Remote Radio Head). The base station 20 may be a receiving station such as an FPU (Field Pickup Unit). The base station 20 may be an IAB (Integrated Access and Backhaul) donor node or an IAB relay node that provides radio access lines and radio backhaul lines using time division multiplexing, frequency division multiplexing, or space division multiplexing.

[0065] The wireless access technology used by the base station 20 may be cellular communication technology. The wireless access technology used by the base station 20 may be wireless LAN technology. The wireless access technology used by the base station 20 may be low-power wide-area (LPWA) communication technology. However, the wireless access technology used by the base station 20 is not limited to these and may be other wireless access technologies. The wireless communication used by the base station 20 may be wireless communication using millimeter waves or wireless communication using terahertz waves. The wireless communication used by the base station 20 may be wireless communication using radio waves or wireless communication using infrared or visible light (optical wireless). Furthermore, the base station 20 may be capable of NOMA (Non-Orthogonal Multiple Access) communication with the terminal device 40. Here, NOMA communication refers to communication (transmission, reception, or both) using non-orthogonal resources. Note that the base station 20 may be capable of NOMA communication with other base stations 20.

[0066] The 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. The base station may also 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.

[0067] The concept of a base station (also called a "base station device") includes not only a donor base station but also a relay base station (also called a "relay station"). A relay base station may be any one of an RF Repeater, a Smart Repeater, and an Intelligent Surface. The concept of a base station includes not only a structure with base station functions but also equipment installed in the structure.

[0068] Examples of structures include high-rise buildings, houses, steel towers, station facilities, airport facilities, port facilities, office buildings, school buildings, hospitals, factories, commercial facilities, stadiums, and other buildings. The concept of a structure includes not only buildings, but also non-building structures such as tunnels, bridges, dams, fences, and steel pillars, as well as equipment such as cranes, gates, and wind turbines. The concept of a structure includes not only land (ground in the narrow sense) or underground structures, but also water-based structures such as piers or megafloats, and underwater structures such as ocean observation facilities. A base station can also be referred to as an information processing device.

[0069] The base station 20 may be a donor station or a relay station (relay station). The base station 20 may also be a fixed station or a mobile station. A mobile station is a wireless communication device (e.g., a base station) configured to be mobile. In this case, the base station 20 may be a device installed in a mobile body, or may be the mobile body itself. For example, a relay station with mobility can be considered as the base station 20 as a mobile station. Furthermore, devices that are inherently mobile and have base station functionality (at least part of the base station functionality), such as vehicles, UAVs (Unmanned Aerial Vehicles) represented by drones, and smartphones, also fall under the category of the base station 20 as a mobile station.

[0070] Here, the mobile body may be a mobile terminal such as a smartphone or a mobile phone. The mobile body may be a mobile body that moves on land (ground in the narrow sense) (e.g., a vehicle such as an automobile, bicycle, bus, truck, motorcycle, train, or linear motor car), or a mobile body that moves underground (e.g., in a tunnel) (e.g., a subway). The mobile body may also be a mobile body that moves on water (e.g., a ship such as a passenger ship, cargo ship, or hovercraft), or a mobile body that moves underwater (e.g., a submersible vessel such as a submersible boat, submarine, or unmanned submersible). The mobile body may also be a mobile body that moves in the atmosphere (e.g., an aircraft such as an airplane, airship, or drone).

[0071] The base station 20 may be a terrestrial base station (ground station) installed on the ground. The base station 20 may be a base station located on a structure on the ground, or a base station installed on a mobile object moving on the ground. The base station 20 may be an antenna installed on a structure such as a building and a signal processing device connected to that antenna. The base station 20 may be the structure or the mobile object itself. "Ground" refers not only to land (ground in the narrow sense) but also to ground, on water, and underwater in a broad sense. The base station 20 is not limited to a terrestrial base station. If the communication system 1 is a satellite communication system, the 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.

[0072] The base station 20 is not limited to a ground station. The base station 20 may be a non-terrestrial base station (non-ground station) that can float in the air or space. The base station 20 may be an aircraft station or a satellite station.

[0073] A satellite station is a wireless communication device capable of floating outside the atmosphere. The satellite station may be a device mounted on a space vehicle such as an artificial satellite, or may be the space vehicle itself. A space vehicle is a vehicle that moves outside the atmosphere. The space vehicle may be at least one of an artificial satellite, a spacecraft, a space station, and a probe. Of course, the space vehicle may also be an artificial celestial body other than these. Note that a satellite that serves as a satellite station may be any of a low Earth orbiting (LEO) satellite, a medium Earth orbiting (MEO) satellite, a geostationary Earth orbiting (GEO) satellite, or a highly elliptical orbiting (HEO) satellite. The satellite station may be a device mounted on a low Earth orbiting (LEO), a medium Earth orbiting (MEO), a geostationary Earth orbiting (GEO), or a highly elliptical orbiting (HEO) satellite.

[0074] An aircraft station is a wireless communication device capable of floating in the atmosphere of an aircraft or the like. The aircraft station may be a device mounted on the aircraft or the like, or may be the aircraft itself. The concept of aircraft includes not only heavier-than-air vehicles such as airplanes and gliders, but also lighter-than-air vehicles such as balloons and airships. The concept of aircraft includes not only heavier-than-air vehicles or lighter-than-air vehicles, but also rotorcraft such as helicopters and autogyros. The aircraft station, or an aircraft equipped with an aircraft station, may be an unmanned aerial vehicle such as a drone.

[0075] The concept of unmanned aerial vehicles also includes unmanned aerial systems (UAS) and tethered unmanned aerial systems (UAS). The concept of unmanned aerial vehicles also includes lighter than air UAS (LTA) and heavier than air UAS (HTA). The concept of unmanned aerial vehicles also includes high altitude unmanned aerial system platforms (HAPs).

[0076] 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 be extremely small, such as a femtocell. The base station 20 may have a beamforming function. The base station 20 may form a cell or service area for each beam. Additionally or alternatively, in addition to beamforming, which imparts directionality to the beam, the base station 20 may have a function for pinpointing a desired wave to a specific point by further considering distance information from the antenna of the base station 20. This function may be called beam focusing or point forming. The base station 20 may also be configured to acquire detection data by performing sensing using the beam.

[0077] FIG. 7 is a diagram showing the configuration of a base station 20 according to this embodiment. The base station 20 includes a wireless communication unit 21, a storage unit 22, and a control unit 23. The base station 20 does not necessarily have to include all of these components. The base station 20 may also include components other than these. For example, the base station 20 may include a sensor unit having a configuration similar to the sensor unit 34 of the propagation path control device 30. Note that the configuration shown in FIG. 7 is a functional configuration, and the hardware configuration may be different. Furthermore, the functions of the base station 20 may be distributed and implemented across multiple physically separated components.

[0078] The wireless communication unit 21 is a signal processing unit for wireless communication with other wireless communication devices (e.g., at least one of the terminal device 40 and another base station 20). The wireless communication unit 21 may be referred to as a wireless transceiver or simply as a transceiver. In this case, the wireless communication unit 21 may be a transceiver (hereinafter referred to as a 3GPP transceiver) conforming to the specifications defined in the Technical Specification of the 3rd Generation Partnership Project (3GPP). The 3GPP transceiver may be a 3G transceiver, a 4G (LTE) transceiver, a 5G (NR) transceiver, or a transceiver of a generation after 5G. The wireless communication unit 21 is controlled by the control unit 23. The wireless communication unit 21 supports one or more wireless access methods. The wireless communication unit 21 may support at least one of NR, LTE, B5G, and 6G. The wireless communication unit 21 may support W-CDMA, cdma2000, etc. in addition to NR, LTE, B5G, and 6G. The wireless communication unit 21 may support automatic retransmission techniques 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.

[0079] The wireless communication unit 21 includes a transmission processing unit 211, a reception processing unit 212, and an antenna 213. At least one of the transmission processing unit 211, the reception processing unit 212, and the antenna 213 may be considered as the wireless communication unit 21. The wireless communication unit 21 may include a plurality of transmission processing units 211, a plurality of reception processing units 212, and a plurality of antennas 213. When the wireless communication unit 21 supports a plurality of wireless access methods, each unit of the wireless communication unit 21 may be configured individually for each wireless access method. The transmission processing unit 211 and the reception processing unit 212 may be configured individually for LTE, NR, B5G, and 6G. The antenna 213 may be configured with a plurality of antenna elements, for example, a plurality of 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 using vertical polarization (V polarization) and horizontal polarization (H polarization) (or a polarization beamforming function using dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical direction).

[0080] The transmission processing unit 211 performs transmission processing of the 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 a coding method such as block coding, convolutional coding, or turbo coding. Here, the encoding may be performed using polar codes or low density parity check codes (LDPC codes). The transmission processing unit 211 then modulates the coded bits using a predetermined modulation method (e.g., 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 need to be equidistant. The constellation may be a non-uniform constellation (NUC). The transmission processing unit 211 then multiplexes the modulation symbols of each channel and the downlink reference signal and allocates the multiplexed signal to predetermined resource elements. The transmission processing unit 211 then performs various signal processing on the multiplexed signal. For example, the transmission processing unit 211 performs processes such as conversion to the frequency domain by fast Fourier transform, addition of a guard interval (cyclic prefix), generation of a baseband digital signal, conversion to an analog signal, quadrature modulation, up-conversion, removal of unnecessary frequency components, power amplification, etc. The signal generated by the transmission processing unit 211 is transmitted from an antenna 213.

[0081] The reception processing unit 212 processes the uplink signal received via the antenna 213. For example, the reception processing unit 212 performs downconversion, removal of unnecessary frequency components, control of amplification level, quadrature demodulation, conversion to a digital signal, removal of guard intervals (cyclic prefixes), extraction of frequency domain signals by fast Fourier transform, and the like on the uplink signal. The reception processing unit 212 then separates uplink channels such as a PUSCH (Physical Uplink Shared Channel) and a PUCCH (Physical Uplink Control Channel) and an uplink reference signal from the signal that has undergone these processes. Furthermore, the reception processing unit 212 demodulates the received signal using a modulation method such as BPSK (Binary Phase Shift Keying) or QPSK (Quadrature Phase Shift Keying) for the modulation symbols of the uplink channel. The modulation method used for demodulation may be 16QAM (Quadrature Amplitude Modulation), 64QAM, or 256QAM. In this case, the signal points on the constellation do not necessarily have to be equidistant. The constellation may be a non-uniform constellation (NUC). The reception processing unit 212 then performs decoding processing on the coded bits of the demodulated uplink channel. The decoded uplink data and uplink control information are output to the control unit 23.

[0082] The antenna 213 is an antenna device that converts electric current and radio waves into each other. The antenna 213 may be configured with a single antenna element, for example, a single patch antenna. The antenna 213 may be configured with multiple antenna elements, for example, multiple patch antennas. When the antenna 213 is configured with 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 a wireless signal using the multiple antenna elements. The antenna 213 may be a dual-polarized antenna. When the antenna 213 is a dual-polarized antenna, the wireless communication unit 21 may use vertical polarization (V polarization) and horizontal polarization (H polarization) (or dual polarization with polarization directions at 45 degrees and -45 degrees from the vertical direction) when transmitting a wireless signal. The wireless communication unit 21 may control the directivity of a wireless signal transmitted using vertical polarization and horizontal polarization (or dual polarization with polarization directions at 45 degrees and -45 degrees from the vertical direction). Furthermore, the wireless communication unit 21 may transmit and receive spatially multiplexed signals via multiple layers each consisting of multiple antenna elements.

[0083] The storage unit 22 is a readable and writable storage device such as a DRAM, an SRAM, a flash memory, a hard disk, etc. The storage unit 22 functions as a storage means of the base station 20.

[0084] The control unit 23 is a controller that controls each unit of the base station 20. The control unit 23 controls the wireless communication unit to perform wireless communication with other wireless communication devices (e.g., terminal devices 40 or other base stations 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 a processor executing various programs stored in a storage device inside the base station 20 using RAM or the like as a work area. The control unit 23 may be implemented by an integrated circuit such as an ASIC or FPGA. The control unit 23 may also be implemented by a GPU. A CPU, MPU, ASIC, FPGA, and GPU can all be considered 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. The control unit 23 may have the functionality of a Near-Real Time RIC.

[0085] The operation of the control unit 23 may be similar to the operation of each block included in the control unit 33 of the propagation path control device 30, or may be similar to the operation of each block included in the control unit 53 of the control station 50. The operation of the control unit 23 may also be similar to the operation of the control unit 43 of the terminal device 40, or may be similar to the operation of the control unit 13 of the management device 10.

[0086] In some embodiments, the base station 20 may be configured as a collection of multiple physical or logical devices. As an example, the base station 20 of this embodiment may be divided into multiple devices such as a baseband unit (BBU) and a radio unit (RU). The base station 20 may be interpreted as a collection of these multiple devices. Furthermore, the base station may be either a BBU or an RU, or may be both. The BBU and the RU may be connected by a predetermined interface such as an enhanced Common Public Radio Interface (eCPRI).

[0087] The RU may be referred to as an RRU (Remote Radio Unit) or an RD (Radio DoT). The RU may correspond to a gNB-DU (gNB Distributed Unit) described later. The BBU may correspond to a gNB-CU (gNB Central Unit) described later. The RU may be a device integrally formed with an 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 such as FD-MIMO or beamforming. The antenna of the base station 20 may include, for example, 64 transmitting antenna ports and 64 receiving antenna ports.

[0088] The antenna mounted on the RU may be an antenna panel consisting 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-handed circularly polarized antenna panel and a left-handed circularly polarized antenna panel, or an antenna panel with a polarization direction at 45 degrees from the vertical direction and an antenna panel with a polarization direction at -45 degrees from the vertical direction. Multiple antennas with these multiple polarization directions may be mounted on a single antenna panel. The RU may form and control an independent beam for each antenna panel.

[0089] A plurality of 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 station 20 may be simply referred to as a RAN, a RAN node, an AN (Access Network), an AN node, or the like. The RAN in LTE may be called an Enhanced Universal Terrestrial RAN (EUTRAN). The RAN in NR may be called an NGRAN. Furthermore, the RAN in 6G may be called a 6GRAN. The RAN in W-CDMA (UMTS) may be called a UTRAN.

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

[0091] When the base station 20 is an eNB, gNB, 6GNB, or the like, the base station 20 may be referred to as a 3GPP access. When the base station 20 is a wireless access point, the base station 20 may be referred to as a non-3GPP access. The base station 20 may be a radio device called an RRH (Remote Radio Head). When the base station 20 is a gNB, the base station 20 may be a combination of the gNB-CU and gNB-DU described above, or may be either a gNB-CU or a gNB-DU.

[0092] Here, the gNB-CU hosts multiple upper layers (e.g., RRC (Radio Resource Control), SDAP (Service Data Adaptation Protocol), PDCP (Packet Data Convergence Protocol)) of the access stratum for communication with the UE. On the other hand, the gNB-DU hosts multiple lower layers (e.g., RLC (Radio Link Control), MAC (Medium Access Control), PHY (Physical layer)) of the access stratum. That is, among the messages / information described below, RRC signaling (semi-static notification) is generated by the gNB-CU, while MAC The CE and DCI (dynamic notification) may be generated by the gNB-DU. Alternatively, some configurations of the RRC configuration (semi-static notification), such as IE:cellGroupConfig, may be generated by the gNB-DU, and the remaining configurations may be generated by the gNB-CU. These configurations may be transmitted and received via the F1 interface described below. The gNB-CU and gNB-DU may be connected to a Near-Real Time RIC via the E2 interface.

[0093] The base station 20 may be configured to be able to communicate with other base stations. When multiple base stations 20 are eNBs or a combination of eNBs and en-gNBs, these base stations 20 may be connected via an X2 interface. When multiple base stations 20 are gNBs or a combination of gn-eNBs and gNBs, these base stations 20 may be connected via an Xn interface. When multiple base stations 20 are a combination of gNB-CUs and gNB-DUs, these base stations 20 may be connected via the F1 interface described above. Messages / information (e.g., RRC signaling, MAC Control Element (CE), or Downlink Control Information (DCI)) described below may be transmitted between multiple base stations 20 via, for example, the X2 interface, the Xn interface, or the F1 interface.

[0094] A cell provided by the base station 20 may be referred to as a serving cell. The concept of a serving cell includes a PCell (Primary Cell) and an SCell (Secondary Cell). When dual connectivity is provided to the terminal device 40, a PCell and zero or more SCells provided by a Master Node (MN) may be referred to as a Master Cell Group. Examples of dual connectivity include EUTRA-EUTRA Dual Connectivity, EUTRA-NR Dual Connectivity (ENDC), EUTRA-NR Dual Connectivity with 5GC, NR-EUTRA Dual Connectivity (NEDC), and NR-NR Dual Connectivity. Further examples of dual connectivity include NR-6G Dual Connectivity and 6G-NR Dual Connectivity.

[0095] The 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 a Secondary Node (SN) and zero or more SCells may be referred to as a Secondary Cell Group (SCG). Unless special configuration (e.g., PUCCH on SCell) is performed, the Physical Uplink Control Channel (PUCCH) is transmitted by the PCell and PSCell but not by the SCell. Radio link failure is detected by the PCell and PSCell but not (does not need to be detected by) the SCell. As such, the PCell and PSCell play special roles among serving cells and are therefore also referred to as Special Cells (SpCells).

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

[0097] <2-3. Configuration of Propagation Path Control Device> Next, the configuration of the propagation path control device 30 will be described.

[0098] The propagation path control device 30 is a control device that dynamically changes the propagation path of radio waves. The propagation path control device 30 is typically a Reconfigurable Intelligent Surface (RIS). In the following description, the propagation path control device 30 may be referred to as RIS 30.

[0099] The propagation path control device 30 may be a RIS (referred to as a Cooperative RIS in this embodiment) that operates in cooperation with communication devices such as the base station 20, or may be a RIS (referred to as a Blind RIS in this embodiment) that operates without cooperation with communication devices. The propagation path control device 30 may also be a RIS that reflects or transmits incoming radio waves without amplifying them (referred to as a passive RIS in this embodiment), or a RIS that amplifies and reflects or transmits incoming radio waves (referred to as an active RIS in this embodiment). The propagation path control device 30 may be a device called a metasurface reflector or a device called a smart repeater. The propagation path control device 30 is not limited to a reflective device and may be, for example, a transmissive device. The term "propagation path control device 30" used in the following description may be rephrased as a RIS, IRS, IS, metasurface, smart surface, intelligent surface, metamaterial, or relay device.

[0100] The propagation path control device 30 has a structure that reflects or transmits the arriving radio waves. For example, the propagation path control device 30 may have, as a structure, a reflector formed of one or more metasurfaces (metasurface elements) that can dynamically control the permittivity and / or magnetic permeability. The propagation path control device 30 may also have, as a structure, a transmission plate that can control the refractive index and the like of the radio waves that pass through. The propagation path control device 30 then controls the reflection characteristics (e.g., reflection direction / reflectance, etc.) or transmission characteristics (e.g., refraction direction / transmittance, etc.) of the structure, thereby reflecting or transmitting the arriving radio waves at a desired angle.

[0101] The propagation path control device 30 may be a device installed on the outer wall of a structure such as a building. By installing the propagation path control device 30 on the outer wall of the structure, even if there is an obstruction between the base station 20 and the terminal device 40, a signal from the base station 20 can be reflected by the propagation path control device 30 provided on the outer wall of the building and reach the terminal device 40. The propagation path control device 30 may also be a device mounted on a device. In this case, the propagation path control device 30 may be a mobile device. The mobile device may be a floating device. For example, the propagation path control device 30 may be mounted on a terminal device such as a smartphone, a vehicle such as an automobile, a train, or a rickshaw, an air vehicle (floating body) such as a balloon, an airplane, or a drone, a facility such as a traffic light, a sign, or a street light, or a home appliance such as a television, a game console, an air conditioner, a refrigerator, or a lighting fixture.

[0102] FIG. 8 is a diagram illustrating an example configuration of a propagation path control device 30 according to an embodiment of the present disclosure. The propagation path control device 30 includes a communication unit 31, a storage unit 32, a control unit 33, a sensor unit 34, and a surface unit 35. The propagation path control device 30 does not necessarily include all of these components. For example, the propagation path control device 30 does not necessarily include the sensor unit 34. The propagation path control device 30 may also include a plurality of these components. For example, the propagation path control device 30 may include a plurality of surface units 35. In this case, the plurality of surface units 35 may face different directions. Note that the configuration illustrated in FIG. 8 is a functional configuration, and the hardware configuration may be different from this. Furthermore, the functions of the propagation path control device 30 may be distributed and implemented in a plurality of physically separated components.

[0103] The communication unit 31 is a communication interface for communicating with other communication devices (for example, the management device 10, the base station 20, the terminal device 40, the control station 50, or another propagation path control device 30). The communication unit 31 may be a network interface or a device connection interface. The communication unit 31 may be a LAN (Local Area Network) interface such as a NIC (Network Interface Card), or may be a USB (Universal Serial Bus) interface configured by a USB host controller or a USB port. The communication unit 31 may be a wired interface or a wireless interface. The communication unit 31 is controlled by the control unit 33.

[0104] The storage unit 32 is a storage device that can read and write data, such as a DRAM, an SRAM, a flash memory, or a hard disk.

[0105] The control unit 33 is a controller (control device) that controls each unit of the propagation path control device 30. The control unit 33 is realized by a processor such as a CPU, an MPU, or a GPU. For example, the control unit 33 is realized by a processor executing various programs stored in a storage device inside the propagation path control device 30 using RAM or the like as a work area. The control unit 33 may be realized by an integrated circuit such as an ASIC or an FPGA. The control unit 33 may also be realized by a GPU. A CPU, an MPU, an ASIC, an FPGA, and a GPU can all be considered 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.

[0106] The control unit 33 includes at least one block of an acquisition unit 331, a determination unit 332, a decision unit 333, and a propagation path control unit 334. Each block (acquisition unit 331 to propagation path control unit 334) constituting the control unit 33 is a functional block that indicates 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 software module realized by software (including a microprogram), or may be a circuit block on a semiconductor chip (die). Of course, each functional block may be a processor or an integrated circuit. The control unit 33 may be configured by functional units different from the above-mentioned functional blocks. The method of configuring the functional blocks is arbitrary.

[0107] The operation of the control unit 33 may be similar to the operation of each block included in the control unit 53 of the control station 50. The operation of the control unit 33 may also be similar to the operation of the control unit 23 of the base station 20, or similar to the operation of the control unit 43 of the terminal device 40. The operation of the control unit 33 may also be similar to the operation of the control unit 13 of the management device 10. The control unit 33 may also be configured to control the surface unit 35 of one or more other propagation path control devices 30.

[0108] The sensor unit 34 is a sensor that acquires various types of information related to wireless communication. For example, the sensor unit 34 is a sensor that acquires information about objects around the device. For example, the sensor unit 34 is a sensor that acquires information about the position, shape, movement, etc. of other objects.

[0109] The sensor unit 34 is not limited to a sensor that acquires information about objects around the device. The sensor unit 34 may be a sensor that detects the state of the device itself (for example, the position, moving speed, tilt, vibration, rotation, etc. of the propagation path control device 30). In this case, too, the sensor unit 34 can be considered as a sensor that acquires various information related to wireless communication.

[0110] The sensor unit 34 may be an RF (Radio Frequency) sensor or a non-RF sensor. Alternatively, the sensor unit 34 may be a sensor system (for example, a sensor unit or a sensor module) that combines an RF sensor and a non-RF sensor.

[0111] Here, an RF sensor refers to a component that uses radio waves for measurement. An example of an RF sensor is a radar that uses radio waves such as millimeter waves. In this case, the radio waves used by the radar are not limited to radio waves in the millimeter wave band (e.g., 30 to 300 GHz band), but may also be radio waves in the microwave band (e.g., 3 to 30 GHz band) or quasi-millimeter wave band (e.g., 20 to 30 GHz band).

[0112] Another example of an RF sensor is a wireless positioning sensor (wireless positioning system). An example of a wireless positioning sensor is a Global Navigation Satellite System (GNSS) sensor. The GNSS sensor may be a Global Positioning System (GPS) sensor, a GLONASS sensor, a Galileo sensor, or a Quasi-Zenith Satellite System (QZSS) sensor. The wireless positioning sensor is not limited to a GNSS sensor, and may be, for example, a sensor for 3GPP positioning or Wi-Fi / Bluetooth positioning.

[0113] A non-RF sensor refers to a component that performs measurements without using radio waves. An example of a non-RF sensor is a ranging sensor (ranging system) such as LiDAR (Light Detection and Ranging). In this case, the light (e.g., laser light) used by the ranging sensor is not limited to visible light, and may be invisible light such as ultraviolet light, infrared light, or near-infrared light. Another example of a non-RF sensor is sonar that uses sound waves such as ultrasound.

[0114] Another example of a non-RF sensor is a camera. The camera is not limited to a visible light camera. For example, the camera may be a near-infrared camera, a mid-infrared camera, or a far-infrared camera. The camera may be a monocular camera or a stereo camera. Another example of a non-RF sensor may be an image sensor. In this case, the image sensor may have image plane phase difference pixels embedded discretely. Alternatively, the sensor unit 34 may be a ToF (Time of Flight) sensor or a microphone.

[0115] Other examples of non-RF sensors include an acceleration sensor (e.g., a three-axis acceleration sensor), a speed sensor, a gyro sensor, an IMU (Inertial Measurement Unit), and other motion sensors. Other examples of non-RF sensors include a magnetic sensor, a barometer, and an altimeter (e.g., a barometer).

[0116] Furthermore, the sensor unit 34 may be a sensor that acquires various information for predicting the quality of a communication path (for example, a communication path formed by a wireless communication unit). For example, the sensor unit 34 is a sensor that detects the reception S / N of radio waves received from another communication device (for example, a communication device that is the communication partner, or a communication device other than the communication partner). Of course, the information acquired by the sensor unit 34 is not limited to the reception S / N, as long as it can be used to predict the quality of the communication path.

[0117] Of course, the sensor unit 34 is not limited to the above-mentioned sensors, and may be a sensor system that combines a plurality of the above-mentioned sensors.

[0118] The surface unit 35 is a structure that reflects or transmits the incoming radio waves. For example, the surface unit 35 is a reflector formed of a metasurface (metasurface element) whose permittivity and / or permeability can be dynamically controlled. The surface unit 35 may be a transmission plate configured to transmit the incoming radio waves and capable of controlling the refractive index, etc., of the transmitted radio waves. The propagation path control device 30 is not limited to a plate shape. For example, the propagation path control device 30 may be a sheet shape. A metasurface is a type of artificial medium (metamaterial) that realizes desired characteristics (e.g., permittivity, permeability, etc.) by periodically arranging structures that are small relative to the wavelength. The control unit 33 can control, for example, the amplitude, phase, polarization, or frequency of the incoming radio waves by manipulating the characteristics (e.g., reflection characteristics or transmission characteristics) of the metasurface provided by the surface unit 35. The structure provided by the propagation path control device 30 is not limited to a surface shape. The surface unit 35 mentioned in the following description can be rephrased as a metamaterial unit 35, a material unit 35, etc.

[0119] 2-4. Configuration of Terminal Device Next, the configuration of the terminal device 40 will be described.

[0120] The terminal device 40 is a wireless communication device that performs wireless communication with other wireless communication devices (for example, the base station 20 or other terminal devices 40). In the following description, the terminal device 40 may be referred to as a UE 40.

[0121] The terminal device 40 may be any type of information processing device (computer). For example, the terminal device 40 may be a mobile terminal such as a mobile phone, a smart device (smartphone or tablet), a personal digital assistant (PDA), a notebook PC, or a portable game console. The terminal device 40 may also be an imaging device (e.g., a camcorder) equipped with a communication function. The terminal device 40 may also be a motorcycle or a mobile broadcasting vehicle equipped with a communication device such as a field pickup unit (FPU). The terminal device 40 may also be a machine-to-machine (M2M) device or an Internet of Things (IoT) device. The terminal device 40 may also be a wearable device such as a smartwatch.

[0122] Furthermore, the terminal device 40 may be an XR 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 part worn by a user (e.g., a glasses part). Furthermore, the terminal device 40 may be a terminal-linked device consisting of a part worn by a user (e.g., a glasses part) and a terminal part (e.g., a smart device) linked to the part worn by a user.

[0123] The terminal device 40 may be capable of NOMA communication with the base station 20. The terminal device 40 may be able to use an automatic repeat technique such as HARQ when communicating with the base station 20. The terminal device 40 may be capable of sidelink communication with another terminal device 40. The terminal device 40 may be able to use an automatic repeat technique such as HARQ when performing sidelink communication. The terminal device 40 may be capable of NOMA communication when performing sidelink communication with another terminal device 40. The terminal device 40 may be capable of LPWA communication with other wireless communication devices such as the base station 20. The wireless communication used by the terminal device 40 may be wireless communication using millimeter waves. The wireless communication used by the 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.

[0124] 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 in a mobile device, or may be the mobile device itself. The terminal device 40 may be a vehicle that moves on a road, such as an automobile, bus, truck, or motorcycle, or a train that runs on a track, or may be a wireless communication device mounted on the vehicle. The mobile device may be a mobile terminal, or a mobile device that moves on land (in the narrow sense of the word), underground, on water, or underwater. The mobile device may also be a mobile device that moves within the atmosphere, such as an airplane, airship, balloon, or helicopter, or a mobile device that moves outside the atmosphere, such as an artificial satellite. The mobile device may also be a UAV (Unmanned Aerial Vehicle) such as a drone. The terminal device 40 may also be a wireless communication device mounted on the mobile device.

[0125] The terminal device 40 may be capable of simultaneously connecting to and communicating with a plurality of base stations 20 or a plurality of cells. When one base station 20 supports a communication area via a plurality of cells (e.g., pCell or sCell), the plurality of cells can be bundled together to enable communication between the base station 20 and the terminal device 40 by using carrier aggregation (CA) technology, dual connectivity (DC) technology, multi-connectivity (MC) technology, or the like. Alternatively, communication between the terminal device 40 and the plurality of base stations 20 can also be performed via cells of different base stations 20 by coordinated multi-point transmission and reception (CoMP) technology.

[0126] The terminal device 40 may be a relay terminal that relays communications to a remote terminal.

[0127] FIG. 9 is a diagram showing the configuration of a terminal device 40 according to this embodiment. The terminal device 40 includes a wireless communication unit 41, a storage unit 42, and a control unit 43. The terminal device 40 does not necessarily have to include all of these components. The terminal device 40 may include components other than these components. For example, the terminal device 40 may include a sensor unit having a configuration similar to the sensor unit 34 of the propagation path control device 30. Note that the configuration shown in FIG. 9 is a functional configuration, and the hardware configuration may be different from this. Furthermore, the functions of the terminal device 40 may be distributed and implemented in multiple physically separated components.

[0128] The wireless communication unit 41 is a signal processing unit for wireless communication with other wireless communication devices (e.g., a base station 20 or another terminal device 40). The wireless communication unit 41 may be referred to as a wireless transceiver or simply as a transceiver. In this case, the wireless communication unit 41 may be a transceiver of a standard 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 transceiver of a generation after 5G. The wireless communication unit 41 is controlled, for example, by the control unit 43. The wireless communication unit 41 supports one or more wireless access methods. The wireless communication unit 41 may support at least one of NR, LTE, B5G, and 6G. In addition to NR, LTE, B5G, and 6G, the wireless communication unit 41 may also support W-CDMA, cdma2000, and the like. The wireless communication unit 41 may support an automatic repeat technique such as HARQ. A part or all of the processing performed by the wireless communication unit 41 may be performed by the control unit 43.

[0129] The wireless communication unit 41 includes 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 a plurality of transmission processing units 411, a plurality of reception processing units 412, and a plurality of antennas 413. When the wireless communication unit 41 supports a plurality of wireless access methods, each unit of the wireless communication unit 41 may be configured individually for each wireless access method. The transmission processing unit 411 and the reception processing unit 412 may be configured individually for LTE, NR, B5G, and 6G. The antenna 413 may be configured with a plurality of antenna elements, for example, a plurality of 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 using vertical polarization (V polarization) and horizontal polarization (H polarization) (or a polarization beamforming function using dual polarization in polarization directions of 45 degrees and -45 degrees from the vertical direction).

[0130] The storage unit 42 is a readable and writable storage device such as a DRAM, an SRAM, a flash memory, or a hard disk.

[0131] The control unit 43 is a controller that controls each unit of the terminal device 40. The control unit 43 controls the wireless communication unit to perform wireless communication with other wireless communication devices (e.g., the base station 20 or another terminal device 40). The control unit 43 may be implemented by a processor such as a CPU or an MPU. In particular, the control unit 23 may be implemented by a processor executing various programs stored in a storage device internal to the terminal device 40 using RAM or the like as a work area. The control unit 43 may be implemented by an integrated circuit such as an ASIC or an FPGA. The control unit 43 may be implemented by a GPU. A CPU, an MPU, an ASIC, an FPGA, and a GPU can all be considered 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.

[0132] The operation of the control unit 43 may be similar to the operation of each block included in the control unit 33 of the propagation path control device 30, or may be similar to the operation of each block included in the control unit 53 of the control station 50. The operation of the control unit 43 may be similar to the operation of the control unit 23 of the base station 20, or may be similar to the operation of the control unit 13 of the management device 10.

[0133] 2-5. Configuration of the Control Station Next, the configuration of the control station 50 will be described.

[0134] The control station 50 is a control device that centrally controls a plurality of propagation path control devices 30. Note that the control station 50 may control only one propagation path control device 30. The control station 50 is also a type of communication device.

[0135] FIG. 10 is a diagram illustrating an example configuration of a control station 50 according to an embodiment of the present disclosure. The control station 50 includes a communication unit 51, a storage unit 52, a control unit 53, and a sensor unit 54. The control station 50 does not necessarily have to include all of these components. For example, the control station 50 does not necessarily have to include the sensor unit 54. Note that the configuration illustrated in FIG. 10 is a functional configuration, and the hardware configuration may be different from this. Furthermore, the functions of the control station 50 may be distributed and implemented in multiple physically separated components.

[0136] The communication unit 51 is a communication interface for communicating with other communication devices (for example, the management device 10, the base station 20, the propagation path control device 30, the terminal device 40, or another control station 50). The communication unit 51 may be a network interface or a device connection interface. The communication unit 51 may be a LAN (Local Area Network) interface such as a NIC (Network Interface Card), or may be a USB (Universal Serial Bus) interface configured by a USB host controller or a USB port. The communication unit 51 may be a wired interface or a wireless interface. The communication unit 51 is controlled by the control unit 53.

[0137] The storage unit 52 is a storage device that can read and write data, such as a DRAM, an SRAM, a flash memory, or a hard disk.

[0138] The control unit 53 is a controller that controls each unit of the control station 50. The control unit 53 may be realized by a processor such as a CPU or an MPU. In particular, the control unit 53 may be realized by a processor executing various programs stored in a storage device inside the control station 50 using RAM or the like as a work area. The control unit 53 may be realized by an integrated circuit such as an ASIC or an FPGA. The control unit 53 may be realized by a GPU. A CPU, an MPU, an ASIC, an FPGA, and a GPU can all be considered controllers. The control unit 53 may be composed of multiple physically separated objects. For example, the control unit 53 may be composed of multiple semiconductor chips.

[0139] The control unit 53 includes at least one block of an acquisition unit 531, a determination unit 532, a decision unit 533, and a propagation path control unit 534. Each block constituting the control unit 53 (the acquisition unit 531 to the propagation path control unit 534) is a functional block that indicates the function of the control unit 53. These functional blocks may be software blocks or hardware blocks. For example, each of the above-described functional blocks may be a software module realized by software (including a microprogram), or may be a circuit block on a semiconductor chip (die). Of course, each functional block may be a processor or an integrated circuit. The control unit 53 may be configured by functional units different from the above-described functional blocks. The method of configuring the functional blocks is arbitrary.

[0140] The operation of the control unit 53 may be similar to the operation of each block included in the control unit 33 of the propagation path control device 30. The operation of the control unit 53 may also be similar to the operation of the control unit 23 of the base station 20, or similar to the operation of the control unit 43 of the terminal device 40. The operation of the control unit 53 may also be similar to the operation of the control unit 13 of the management device 10. The control unit 53 may also be configured to control the surface units 35 of multiple propagation path control devices 30.

[0141] The sensor unit 54 is a sensor that acquires various information related to wireless communication. For example, the sensor unit 54 is a sensor that acquires information about objects around the device. For example, the sensor unit 54 is a sensor that acquires information about the position, shape, movement, etc. of other objects. The sensor unit 54 may be a sensor that detects the state of the device itself (for example, the position, moving speed, tilt, vibration, rotation, etc. of the control station 50). Alternatively, the configuration of the sensor unit 54 may be the same as the configuration of the sensor unit 34 included in the propagation path control device 30. For example, the sensor unit 54 may be an RF sensor or a non-RF sensor. Furthermore, the sensor unit 54 may be a sensor system that combines an RF sensor and a non-RF sensor.

[0142] <<3. Operation of the Communication System>> The configuration of the communication system 1 has been described above. Next, the operation of the communication system 1 of this embodiment will be described.

[0143] As described above, there are two types of RIS: Cooperative RIS and Blind RIS. Cooperative RIS is a RIS that operates in cooperation with a communication device, while Blind RIS is a RIS that operates without cooperation with a communication device. In this embodiment, the operation of the communication system 1 when the propagation path control device 30 is a Blind RIS will be described in detail.

[0144] <3-1. Normal Operation of RIS> Before describing the operation of the communication system 1 in detail, for comparison, a brief description will be given of the operation of the communication system 1 assumed when the propagation path control device 30 is a Cooperative RIS. Here, the propagation path control device 30 is referred to as RIS 30. Note that the operation of the communication system 1 described in this section (<3-1. Normal Operation of RIS>) can also be considered as part of the operation of the communication system 1 of this embodiment.

[0145] In this section (<3-1. Normal operation of RIS>), it is assumed that the propagation path control device 30 is installed in an environment where one base station 20 and multiple terminal devices 40 exist, as shown in Fig. 2 or 11, for example. It is also assumed that the RIS 30 is connected to the base station 20. The connection between the RIS 30 and the base station 20 may be a wireless connection or a wired connection.

[0146] First, the base station 20 acquires channel information between the base station 20 and the RIS 30 (hereinafter referred to as first channel information) and channel information between the RIS 30 and the terminal device 40 (hereinafter referred to as second channel information). The first channel information and / or the second channel information may be measured by the RIS 30, or may be measured by the base station 20 and / or the terminal device 40. The base station 20 may also acquire channel information between the base station 20 and the terminal device 40 (hereinafter referred to as third channel information). This channel information may be measured by the base station 20, or may be measured by the terminal device 40.

[0147] The base station 20 determines which terminal device 40 the RIS 30 should be used for communication with, based on the acquired channel information (at least one of the first channel information, the second channel information, and the third channel information). The base station 20 transmits control information to the RIS 30 to schedule a reflection pattern or a transmission pattern, based on its own schedule information (e.g., schedule information for the uplink, the downlink, and / or the sidelink). The RIS 30 changes the reflection pattern or the transmission pattern based on the transmitted control information. This operation can be performed when the RIS 30 is connected to the base station 20 and the RIS 30 and the base station 20 operate in the same division unit in the time direction.

[0148] As described above, the reflection pattern is a pattern related to the reflection of an incoming radio wave (e.g., a conversion pattern of an incoming wave or a formation / generation pattern of a reflected wave). For example, the reflection pattern is a combination of configurations of metasurfaces (metasurface elements). Here, the configuration may be setting information for forming / generating a reflected wave for each metasurface (e.g., information related to permittivity and / or permeability). Note that the reflection pattern may also be a waveform pattern of a reflected wave formed by a combination of the configurations. In this embodiment, the formation of a reflection pattern may refer to the RIS 30 changing the permittivity and / or permeability of one or more metasurfaces (metasurface elements), for example, to achieve a state having intended reflection characteristics.

[0149] Furthermore, the transmission pattern is a pattern related to the transmission of incoming radio waves (for example, a conversion pattern of incoming waves or a formation / generation pattern of transmitted waves). For example, the transmission pattern is a combination of metasurface (metasurface element) configurations. Here, the configuration may be setting information for transmitting / generating transmitted waves for each metasurface (for example, information related to permittivity and / or permeability). The transmission pattern may also be a waveform pattern of transmitted waves formed by a combination of the configurations. In this embodiment, the formation of a transmission pattern may refer to the RIS 30 changing the permittivity and / or permeability of one or more metasurfaces (metasurface elements), for example, to achieve the intended transmission characteristics.

[0150] The base station 20 selects the reflection pattern or transmission pattern of the RIS 30 that provides the highest bit rate based on the acquired channel information (at least one of the first channel information, the second channel information, and the third channel information). The base station 20 then transmits information regarding the reflection pattern or transmission pattern to the RIS 30 as control information. The RIS 30 changes the configuration of one or more metasurfaces based on the control information (information regarding the reflection pattern or transmission pattern) from the base station 20. For example, the RIS 30 changes at least one of the phase, frequency, and amplitude of the reflected wave / transmitted wave for each metasurface. When transmitting the reflected wave / transmitted wave, the RIS 30 may perform encoding and / or modulation of the reflected / transmitted signal. In this case, the RIS 30 may change the encoding and / or modulation of the reflected / transmitted signal based on the control information (information regarding the reflection pattern or transmission pattern) from the base station 20.

[0151] 3-2. First Embodiment The operation of the communication system 1 when the RIS is a Cooperative RIS has been described above. Hereinafter, the operation of the communication system 1 when the propagation path control device 30 is a Blind RIS will be described.

[0152] <3-2-1. Communication Environment> First, the communication environment assumed in the first embodiment will be described.

[0153] FIG. 11 is a diagram illustrating an example of a communication environment assumed in Example 1. In Example 1, one or more propagation path control devices 30 are installed in an environment where one or more base stations 20 and multiple terminal devices 40 exist. In the example of FIG. 11, M propagation path control devices 30 are installed in an environment where one base station 20 and N terminal devices 40 exist. N and M are each any integer. The propagation path control device 30 is, for example, a RIS. The propagation path control device 30 may be fixed or movable.

[0154] Each of the multiple terminal devices 40 is connected to the base station 20. The communication between the multiple terminal devices 40 is controlled by a scheduler of the base station 20. In the first embodiment, as an example, it is assumed that communication is performed using a time division multiple access (TDMA) method. That is, in the first embodiment, the base station 20 allocates radio resources to the multiple terminal devices 40 over time. Of course, the connection method is not limited to the TDMA method, and may be a frequency division multiple access (FDMA) method or a code division multiple access (CDMA) method. Furthermore, the connection method may be a combination of multiple different connection methods.

[0155] In the first embodiment, the propagation path control device 30 is not connected to the base station 20 or the terminal device 40. The propagation path control device 30 is controlled by a scheduler independent of these communication devices. In the first embodiment, the propagation path control device 30 itself has a control function (scheduler).

[0156] 3-2-2. Communication Processing Next, a description will be given of the communication processing according to the first embodiment. Fig. 12 is a sequence diagram showing the communication processing according to the first embodiment.

[0157] As described above, in the first embodiment, the propagation path control device 30 is a blind RIS. Note that the propagation path control device 30 may be a device other than a RIS that can control a propagation path. The term "propagation path control device 30" that appears in the following description can be replaced with a RIS, an IRS, an IS, a metasurface, a smart surface, an intelligent surface, a metamaterial, or a repeater.

[0158] In the example of FIG. 12 , the BS is the base station 20, the RIS is the propagation path control device 30, and UE#1 to UE#N are each terminal device 40. In this sequence example, one base station 20 performs wireless communication with each of multiple terminal devices 40 (UE#1 to UE#N). Of course, multiple base stations 20 may exist. Note that although only one propagation path control device 30 is shown in the sequence diagram of FIG. 12 , multiple propagation path control devices 30 may exist in the communication environment as shown in FIG. 11 . In this case, the multiple propagation path control devices 30 may each execute the processing (steps S101 to S104) shown in FIG. 12 . Hereinafter, the communication processing according to the first embodiment will be described with reference to the sequence diagram of FIG. 12 .

[0159] First, the propagation path control device 30 determines the communication devices (base station 20 and / or terminal device 40) that are to be controlled through the propagation path. That is, the propagation path control device 30 determines the communication devices (base station 20 and / or terminal device 40) that it supports (step S101). In the following description, the communication devices that are to be controlled through the propagation path may be referred to as supported communication devices. Furthermore, in the following description, of the supported communication devices, a communication device that transmits a signal may be referred to as a transmitting device, and a communication device that receives a signal may be referred to as a receiving device.

[0160] If the propagation path control device 30 has a function for determining a line of site (LOS) environment, the propagation path control device 30 may determine the communication devices to be supported based on whether or not there is a line of site (LOS) between the propagation path control device 30 and the communication devices.

[0161] Fig. 13 is a flowchart showing an example of the determination process. When the propagation path control device 30 has a function of determining LOS (Line Of Site), the propagation path control device 30 may determine the communication device to be supported, for example, according to the flowchart shown in Fig. 13. The propagation path control device 30 executes the determination process shown in Fig. 13 for each of a plurality of communication devices present in the communication environment.

[0162] First, the propagation path control device 30 determines whether or not there is an LOS between the propagation path control device 30 and the communication device (step S201). Here, "LOS" between the propagation path control device 30 and the communication device means that there is line of sight between the propagation path control device 30 and the communication device. In other words, "LOS" between the propagation path control device 30 and the communication device means that a direct wave can be transmitted from the propagation path control device 30 to the communication device, or from the communication device to the propagation path control device 30. In the following description, "LOS" between the propagation path control device 30 and the communication device may be referred to as "the communication device is in an LOS environment."

[0163] The propagation path control device 30 may determine whether or not the communication device is in an LOS environment based on information sensed using the sensor unit 34. Here, there are two methods for determining whether or not the communication device is in an LOS environment: a method for determining based on an incoming wave, and a method for optical determination.

[0164] (Method of Discrimination Based on Incoming Waves) First, a method of discrimination based on incoming waves will be described. The propagation path control device 30 observes the power and / or delay power profile of the operating frequency band using, for example, a network analyzer. The propagation path control device 30 determines to what extent the incoming wave corresponding to the direct wave is dominant compared to other multipaths. If the direct wave is dominant to a certain extent or more, the propagation path control device 30 determines that the propagation path is an LOS propagation path.

[0165] (Optical Determination Method) Next, an optical determination method will be described. When the propagation path control device 30 has an optical device (imaging device) such as a camera and / or an optical sensor, the propagation path control device 30 determines whether or not an obstruction exists between the communication device and the propagation path control device 30 using image information. Note that the propagation path control device 30 may determine whether or not the communication device is in an LOS environment based on information from another device. For example, it is assumed that the propagation path control device 30 is controlled by a control station 50 connected to an independent network different from the network of the base station 20. In this case, the propagation path control device 30 may determine whether or not the communication device is in an LOS environment based on information acquired from a monitoring system held by the control station 50.

[0166] The method for determining whether or not a communication device is in an LOS environment is not limited to the above example. The propagation path control device 30 may determine whether or not a communication device is in an LOS environment by combining the above two methods, or may determine whether or not a communication device is in an LOS environment using another method. The propagation path control device 30 may determine whether or not a communication device is in an LOS environment using an RF sensor such as a millimeter-wave radar, or may determine whether or not a communication device is in an LOS environment using a non-RF sensor such as a ranging sensor or sonar.

[0167] If the communication device is in an LOS environment (step S201: Yes), the propagation path control device 30 determines that the communication device is a supported communication device (step S202) and ends the process. On the other hand, if the communication device is not in an LOS environment (step S201: No), the propagation path control device 30 ends the process without determining that the communication device is a supported communication device. In other words, if the communication device is not in an LOS environment, the propagation path control device 30 excludes that communication device from its support targets.

[0168] Whether a predetermined communication device is in an LOS environment may be set in advance in the propagation path control device 30. That is, the propagation path control device 30 may always determine whether a predetermined communication device is in an LOS environment or not without performing LOS judgment (for example, judgment using the method described above). For example, in many cases, the propagation path control device 30 is installed taking into consideration the location of the base station 20. Therefore, whether a predetermined base station 20 is in an LOS environment or not may be set in the propagation path control device 30 at the time of installation. Then, when the communication device is a predetermined base station 20, the propagation path control device 30 may determine whether the communication device is in an LOS environment or not in accordance with the setting at the time of installation.

[0169] This method (a method for determining whether a communication device is in an LOS environment without performing LOS determination) is applicable to cases where neither the propagation path control device 30 nor the communication device is moving. For example, when neither the propagation path control device 30 nor the terminal device 40 is moving, the propagation path control device 30 may determine whether the terminal device 40 is in an LOS environment without performing LOS determination. This method is also applicable to cases where one of the propagation path control device 30 and the communication device moves following the other. This method is also applicable to cases where the communication device is always located in a place where there are no obstructions, for example, when the communication device is always in the air where there are no obstructions, like a drone.

[0170] The propagation path control device 30 may remove a communication device that satisfies a specific condition from the list of supported communication devices, regardless of whether the communication device is in an LOS environment. For example, if the moving speed of the communication device meets a predetermined standard, for example, if the moving speed of the communication device is faster than a predetermined speed, the propagation path control device 30 may remove the communication device from the list of supported communication devices. For example, if the propagation path control device 30 determines that the moving speed of a communication device (e.g., a terminal device 40) is so fast that it cannot operate in a manner that tracks the movement of the communication device, the propagation path control device 30 may remove the communication device from the list of supported communication devices. The propagation path control device 30 may determine the moving speed of the communication device based on the Doppler frequency and / or the direction of arrival of radio waves, or based on information from an optical device (imaging device) such as a camera and / or an optical sensor.

[0171] The method of determining the communication device to be supported is not limited to the method shown in Fig. 13. For example, if the propagation path control device 30 does not have a function for determining the LOS (Line Of Site) environment, the propagation path control device 30 may determine the communication device to be supported based on the observation results of the arriving wave.

[0172] 14 is a flowchart showing another example of the determination process. When the propagation path control device 30 does not have a function for determining LOS (Line Of Site), the propagation path control device 30 may determine the communication device to be the control target of the propagation path based on the observation results of the arriving waves. The propagation path control device 30 executes the determination process shown in FIG. 14 for each of the multiple arriving waves.

[0173] First, the propagation path control device 30 determines whether or not the incoming wave satisfies a criterion (step S301). For example, the propagation path control device 30 may determine whether or not the strength of the incoming wave (i.e., the magnitude of the received power) exceeds a predetermined threshold.

[0174] For example, the propagation path control device 30 uses a network analyzer to observe the power and / or delay power profile of the operating frequency band. The propagation path control device 30 may also observe the direction of arrival of an incoming wave. Furthermore, the propagation path control device 30 may determine from which communication device an incoming wave is transmitted, based on control information exchanged between communication devices (e.g., DCI exchanged between the base station 20 and the terminal device 40). For example, the propagation path control device 30 may determine whether an incoming wave is transmitted from the base station 20 or the terminal device 40, based on the DCI exchanged between the base station 20 and the terminal device 40. If it is not possible to determine whether an incoming wave is transmitted from the base station 20 or the terminal device 40, the propagation path control device 30 may simply treat the incoming wave as an incoming wave from a communication device without distinguishing between the base station 20 and the terminal device 40. Then, the propagation path control device 30 may identify from which communication device the incoming wave is transmitted, based on the direction of arrival of the incoming wave. Of course, the propagation path control device 30 may identify from which communication device the incoming wave is coming based on the control information.

[0175] If the incoming wave satisfies the criteria (step S301: Yes), for example, if the strength of the incoming wave exceeds a predetermined threshold, the propagation path control device 30 determines that the communication device that is the source of the incoming wave (for example, a communication device estimated to be located in the direction of arrival of the incoming wave, or a communication device identified as the source by control information) is a supported communication device (step S302), and ends the process. On the other hand, if the incoming wave does not satisfy the criteria (step S301: No), for example, if the strength of the incoming wave is equal to or less than a predetermined threshold, the propagation path control device 30 ends the process without determining that the communication device that is the source of the incoming wave is a supported communication device. In other words, if the communication device is not in an LOS environment, the propagation path control device 30 excludes that communication device from its support targets.

[0176] Note that information on the direction of arrival of an arriving wave (or information on the transmission position of an arriving wave) may be set in advance in the propagation path control device 30. That is, the propagation path control device 30 may always specify that a predetermined arriving wave (e.g., an arriving wave having predetermined information) has been transmitted from a predetermined direction or a predetermined position, without determining the direction of arrival of the arriving wave. For example, in many cases, the propagation path control device 30 is installed taking into consideration the position of the base station 20. Therefore, at the time of installation, the propagation path control device 30 may be set with information on the installation direction or installation position of the base station 20 as information on the direction of arrival or transmission position of the arriving wave. Then, when the arriving wave contains predetermined information (e.g., when the arriving wave contains DCI), the propagation path control device 30 may specify the direction of arrival or transmission position of the arriving wave in accordance with the setting at the time of installation.

[0177] This method (a method for identifying the direction of arrival of an incoming wave or the transmission position without first determining the direction of arrival of the incoming wave) is applicable when both the propagation path control device 30 and the communication device are stationary. This method is also applicable when one of the propagation path control device 30 and the communication device moves while following the other. This method is also applicable when the communication device is always located in a place where there are no obstructions, for example, when the communication device is always in the air where there are no obstructions, like a drone.

[0178] The propagation path control device 30 may remove a communication device that satisfies a specific condition from the list of supported communication devices, regardless of whether the incoming waves satisfy the criteria. For example, the propagation path control device 30 may remove a communication device from the list of supported communication devices if the moving speed of the communication device satisfies a predetermined criterion, for example, if the moving speed of the communication device is faster than a predetermined speed. For example, if the propagation path control device 30 determines that the moving speed of a communication device (e.g., terminal device 40) is so fast that it cannot operate in a manner that tracks the movement of the communication device, the propagation path control device 30 may remove the communication device from the list of supported communication devices. The propagation path control device 30 may determine the moving speed of the communication device based on the Doppler frequency and / or the direction of arrival of radio waves, or based on information from an optical device (imaging device) such as a camera and / or an optical sensor.

[0179] The method of determining a communication device to be supported is not limited to the methods shown in Figures 13 and 14. For example, the propagation path control device 30 may determine a communication device to be supported by combining the method shown in Figure 13 and the method shown in Figure 14. Of course, the propagation path control device 30 may determine a communication device to be supported by using other methods. For example, the propagation path control device 30 may determine a communication device to be supported based on location information of the communication device acquired from another device (for example, another propagation path control device 30).

[0180] Note that, for example, as shown in FIG. 11 , there may be cases where multiple propagation path control devices 30 exist in a communication environment. In this case, the multiple propagation path control devices 30 may each determine the communication device that they will support in an autonomous, distributed manner. In this case, the multiple propagation path control devices 30 may each grasp changes in the reflection patterns or transmission patterns of the other propagation path control devices 30 by observing reflected waves or transmitted waves from the other propagation path control devices 30. Then, the multiple propagation path control devices 30 may each determine the communication device that they will support based on the observation results of the reflected waves or transmitted waves. For example, the multiple propagation path control devices 30 may each determine whether or not to support a communication device to be identified based on whether the communication device is a support control target of another propagation path control device 30.

[0181] Furthermore, the propagation path control device 30 may determine the communication devices that it supports based on the monitoring results of control information exchanged between communication devices (for example, DCI exchanged between the base station 20 and the terminal device 40). For example, the propagation path control device 30 may identify one or more terminal devices 40 connected to a specific base station 20 (specific cell) by observing the DCI. Then, the propagation path control device 30 may determine one or more terminal devices 40 connected to the specific base station 20 (specific cell) as the communication devices that it supports. In this way, the propagation path control device 30 can support communication only for terminal devices 40 connected to a specific base station 20 (specific cell), rather than supporting communication of terminal devices 40 across multiple cells.

[0182] When allocation of communication devices to be supported among a plurality of propagation path control devices 30 is determined, the decision may take into consideration the movement speed of the communication devices. For example, if there is a difference in performance among a plurality of propagation path control devices 30, a decision may be made so that a propagation path control device 30 that can keep up with the movement speed of a terminal device 40 supports that communication device. This decision may be made by each of the plurality of propagation path control devices 30 in an autonomous and decentralized manner. In this case, the propagation path control device 30 may determine the movement speed of the communication device based on the Doppler frequency and / or the direction of arrival of radio waves, or may determine the movement speed based on information from an optical device (imaging device) such as a camera and / or an optical sensor.

[0183] Returning to FIG. 12, the propagation path control device 30 determines a schedule for forming a plurality of reflection patterns or a plurality of transmission patterns corresponding to a plurality of communication devices to be supported (step S102).

[0184] Here, the reflection pattern is a pattern related to the reflection of an incoming radio wave (for example, a conversion pattern of an incoming wave, or a formation / generation pattern of a reflected wave). For example, the reflection pattern is a combination of configurations of a metasurface (metasurface element). Here, the configuration may be setting information for forming / generating a reflected wave for each metasurface (for example, information related to permittivity and / or permeability). Note that the reflection pattern may also be a waveform pattern of a reflected wave formed by a combination of the configurations. In this embodiment, the formation of a reflection pattern may refer to the RIS changing the permittivity and / or permeability of one or more metasurfaces (metasurface elements), for example, to achieve the intended reflection characteristics.

[0185] Furthermore, the transmission pattern is a pattern related to the transmission of the incoming radio waves (for example, a conversion pattern of the incoming wave or a formation / generation pattern of the transmitted wave). For example, the transmission pattern is a combination of configurations of metasurfaces (metasurface elements). Here, the configuration may be setting information for the formation / generation of the transmitted wave for each metasurface (for example, information related to the permittivity and / or permeability). Note that the transmission pattern may also be a waveform pattern of the transmitted wave formed by the combination of the configurations. In this embodiment, the formation of a transmission pattern may refer to the RIS changing the permittivity and / or permeability of one or more metasurfaces (metasurface elements), for example, to achieve the intended transmission characteristics.

[0186] The propagation path control device 30 forms a reflection pattern or a transmission pattern so as to improve the communication quality of the communication device to be supported. For example, the propagation path control device 30 may form a reflection pattern or a transmission pattern simply so as to improve the received power of the signal at the receiving device.

[0187] Furthermore, when a path between communication devices (for example, between the base station 20 and the terminal device 40) is blocked by an obstruction, the propagation path control device 30 may form a reflection pattern or a transmission pattern so as to form a propagation path that bypasses the obstruction. For example, when a direct wave from a transmitting device to a receiving device is blocked by an obstruction, the propagation path control device 30 may form a reflection pattern or a transmission pattern so as to form a propagation path that bypasses the obstruction. Securing a propagation path that passes through the propagation path control device 30 improves the received power of a signal received by the communication device.

[0188] Furthermore, the propagation path control device 30 may form reflected waves or transmitted waves so as to improve the MIMO channel. At this time, the propagation path control device 30 may estimate MIMO eigenvalues ​​on the receiving device side and adjust the phase and / or frequency at the receiving device.

[0189] Furthermore, the propagation path control device 30 may form a reflection pattern or a transmission pattern so as to reduce interference with one or more communication devices included in the communication system to which the propagation path control device 30 belongs, or may form a reflection pattern or a transmission pattern so as to reduce interference with one or more communication devices included in other communication systems. Furthermore, the propagation path control device 30 may form a reflection pattern or a transmission pattern so as to reduce interference with one or more communication devices included in the communication system to which the propagation path control device 30 belongs, or may form a reflection pattern or a transmission pattern so as to reduce interference with one or more communication devices included in other communication systems. Specific methods for reducing interfered waves / interference include a method in which the propagation path control device 30 forms a reflection pattern or a transmission pattern so as to form a null beam in the direction of the target, and a method in which the propagation path control device 30 forms a reflection pattern or a transmission pattern so as to scatter reflected waves.

[0190] When multiple propagation path control devices 30 operate in cooperation with each other, a propagation path control device 30 may grasp changes in the reflection pattern or transmission pattern of another propagation path control device 30 by observing the reflected wave or transmitted wave from the other propagation path control device 30. Then, each of the multiple propagation path control devices 30 may form a reflection pattern or transmission pattern based on the observation results of the reflected wave or transmitted wave.

[0191] The propagation path control device 30 may determine the schedule by allocating the formation times of reflection patterns or transmission patterns to a plurality of communication devices (for example, a plurality of terminal devices 40) based on a predetermined rule.

[0192] For example, the propagation path control device 30 may allocate a formation time of a reflection pattern or a transmission pattern to a plurality of communication devices (e.g., a plurality of terminal devices 40) based on the PF (Proportional Fair) rule (also referred to as Proportional Fair Scheduling or Proportional Fair Sharing). For example, the propagation path control device 30 may calculate fairness according to a specific index for each communication device, and allocate a formation time of a reflection pattern or a transmission pattern to each communication device so that the fairness improves. The index of fairness may be at least one of throughput, MCS, reception SNR, reception SINR, and rank index.

[0193] The predetermined criterion is not limited to the PF criterion. The propagation path control device 30 may allocate reflection pattern or transmission pattern formation times to multiple communication devices so as to improve (e.g., maximize / minimize) a specific index. For example, the propagation path control device 30 may allocate reflection pattern or transmission pattern formation times to each communication device so as to improve the lowest or highest index among multiple indexes (e.g., two or more indexes selected from throughput, MCS, received SNR, received SINR, and rank index).

[0194] Furthermore, the predetermined standard may be a standard based on information related to communication (reflected or transmitted signals). For example, the propagation path control device 30 may allocate a time for forming a reflection pattern or a transmission pattern according to the purpose or priority of the communication. For example, the communication may be prioritized according to the requirements of network design. The propagation path control device 30 may also prioritize the communication based on control information exchanged between communication devices (for example, DCI exchanged between the base station 20 and the terminal device 40). Then, the propagation path control device 30 may allocate a time for forming a reflection pattern or a transmission pattern to each communication device according to the priority.

[0195] When there are multiple communication devices with the same priority (e.g., communication devices with the same communication purpose), the propagation path control device 30 may allocate the formation times to those communication devices equally in a round-robin format, or may allocate the formation times based on a specific rule. The specific rule may be the same as the predetermined rule described above. For example, the propagation path control device 30 may allocate the formation times of the reflection pattern or transmission pattern to those communication devices based on the PF rule, or may allocate the formation times of the reflection pattern or transmission pattern to those communication devices so as to improve (e.g., maximize / minimize) a specific index.

[0196] It is also assumed that, in cases where restrictions on interference are required under specific laws and regulations, communications for specific purposes may be given priority from the viewpoint of interference protection. The propagation path control device 30 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a communication device that performs communications for that specific purpose.

[0197] Alternatively, the propagation path control device 30 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a specific communication device. Furthermore, the propagation path control device 30 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a communication device with a low throughput, MCS, reception SNR, reception SINR, or rank index. Furthermore, the propagation path control device 30 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a communication device with a high traffic volume. Furthermore, the propagation path control device 30 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a communication device with a high QoS requirement. Furthermore, the propagation path control device 30 may equally allocate the formation time of a reflection pattern or a transmission pattern to a plurality of communication devices in a round robin format.

[0198] 15 to 17 are diagrams showing examples of allocation of the formation times of the reflective patterns and the transmissive patterns, respectively.

[0199] 15 and 16, the propagation path control device 30 allocates reflection pattern or transmission pattern formation times to N terminal devices 40 UE#1 to UE#N during a time period of length P1. In the example of Fig. 15, the propagation path control device 30 allocates reflection pattern or transmission pattern formation times to UE#1, UE#3, UE#2, ..., UE#N in a ratio of 3:1:2: ...:2. In the example of Fig. 16, the propagation path control device 30 allocates reflection pattern or transmission pattern formation times to UE#1, UE#3, UE#2, ..., UE#N in a ratio of 1:1:2: ...:1.

[0200] 17, the propagation path control device 30 allocates a time period with a length P2 different from P1 for forming a reflection pattern or a transmission pattern to each of N terminal devices 40, UE#1 to UE#N. In the example of Fig. 16, the propagation path control device 30 allocates a time period for forming a reflection pattern or a transmission pattern to UE#1, UE#3, UE#2, ..., UE#N in a ratio of 1:1:2: ...:1.

[0201] The operation unit of the scheduler of the propagation path control device 30 may be the operation unit of the scheduler of the base station 20 (for example, slot length), or may be the same time length as the Rank Index feedback period of MIMO communication, or may be the same time length as the MCS change interval (for example, 10 to 100 ms). Here, the operation unit of the scheduler is, for example, the allocation unit of the formation time of a reflection pattern or a transmission pattern.

[0202] In the example of Fig. 15, the allocation unit of the formation time of the reflective pattern or the transmissive pattern is r1, which corresponds to the shortest allocated time among the multiple allocated times. In the example of Fig. 16, the allocation unit of the formation time of the reflective pattern or the transmissive pattern is r2, which corresponds to the shortest allocated time among the multiple allocated times. In the example of Fig. 17, the allocation unit of the formation time of the reflective pattern or the transmissive pattern is r2, which corresponds to the shortest allocated time among the multiple allocated times.

[0203] When the operation unit of the scheduler of the propagation path control device 30 is matched to the operation unit (for example, slot length) of the scheduler of the base station 20, the schedule of the propagation path control device 30 needs to follow the schedule of the base station 20 to some extent. This increases the difficulty of scheduling. Therefore, the propagation path control device 30 may use a multiple slot length (for example, 1 to 10 ms) as the schedule operation unit.

[0204] Returning to Fig. 12, once a schedule has been determined, the propagation path control device 30 repeatedly executes that schedule (step S103). If the schedule shown in Fig. 15 or 16 has been determined, the propagation path control device 30 repeatedly executes the schedule with a length of P1. If the schedule shown in Fig. 17 has been determined, the propagation path control device 30 repeatedly executes the schedule with a length of P2.

[0205] The propagation path control device 30 may update the determined schedule at a predetermined timing (step S104). For example, the propagation path control device 30 may update the schedule at regular intervals. For example, the propagation path control device 30 may update the schedule at an update interval set at the time of installation or an update interval specified by a standard. The schedule update interval is, for example, 1 to 60 minutes.

[0206] Furthermore, the propagation path control device 30 may update the schedule when a predetermined condition is satisfied. For example, the propagation path control device 30 may update the schedule when a change in the communication environment is detected. For example, the propagation path control device 30 may update the schedule in at least one of the following cases: when a new communication device is detected, when a communication device to be controlled no longer communicates, and when the communication volume of a communication device to be controlled has changed from a predetermined standard.

[0207] Furthermore, the propagation path control device 30 may update the schedule based on a signal transmitted from another device (for example, the management device 10, the base station 20, the terminal device 40, the control station 50, or another propagation path control device 30). For example, the propagation path control device 30 may update the schedule in at least one of the following cases: when a signal requesting re-setting of the schedule is received from another device; and when a signal requesting a change of the communication device to be supported is received from another propagation path control device 30.

[0208] Furthermore, the propagation path control device 30 may update (reset) the schedule when it is determined that its own schedule is not well reflected in the schedule of the base station 20. For example, the propagation path control device 30 may update (reset) the schedule when there is a significant mismatch between the destination of a signal transmitted by the base station 20 and the reflection pattern or transmission pattern scheduled by itself. In this case, the propagation path control device 30 may change the schedule operation unit (e.g., r1, r2, or r3 shown in FIGS. 15 to 17) or may change the schedule operation period (e.g., P1 or P2 shown in FIGS. 15 to 17) so that its own schedule is more easily reflected in the base station 20.

[0209] For example, if the schedule time of the base station 20 to each terminal device 40 is short relative to the length of time allocation (e.g., schedule operation unit) of the propagation path control device 30, the schedule is reset so as to shorten the length of time allocation of the propagation path control device 30. Conversely, if the schedule time of the base station 20 to each terminal device 40 is long relative to the length of time allocation of the propagation path control device 30 (e.g., schedule operation unit), the schedule is reset so as to lengthen the length of time allocation of the propagation path control device 30.

[0210] The propagation path control device 30 may assign a plurality of different reflection patterns or a plurality of different transmission patterns at the same time. For example, if the size of the surface section 35 of the propagation path control device 30 is sufficiently large, a first reflection pattern or a first transmission pattern may be assigned to a part of the surface section 35, and a second reflection pattern or a second transmission pattern may be assigned to another part of the surface section 35. In this case, the propagation path control device 30 may determine the area of ​​the surface section 35 to be assigned to a predetermined reflection pattern or a predetermined transmission pattern based on the above-mentioned predetermined standard.

[0211] 12, once the schedule update is complete, the propagation path control device 30 repeatedly executes the updated schedule (step S105). Thereafter, the propagation path control device 30 repeatedly updates and executes the schedule.

[0212] According to this embodiment, even when the propagation path control device 30 is not connected to a communication device (e.g., a base station 20) that schedules wireless communication, a good propagation path is formed for a specific communication device (e.g., a terminal device 40) at a specific timing in a specific period. As a result, the communication device (e.g., a base station 20) that schedules wireless communication determines a communication schedule (e.g., an uplink, downlink, and / or sidelink schedule) so as to communicate with the specific communication device (e.g., a terminal device 40) at that timing. In other words, the schedule of the propagation path control device 30 is reflected in the communication schedule of the communication device in an autonomous and decentralized manner. As a result, the propagation path control device 30 can switch between a reflection pattern and a transmission pattern according to the communication schedule of the communication device, thereby achieving effective use of radio wave resources.

[0213] 3-3. Second Embodiment Next, an operation of the communication system 1 according to the second embodiment will be described. In the second embodiment, the propagation path control device 30 is also a Blind RIS. In the second embodiment, a plurality of propagation path control devices 30 are controlled by a control station 50.

[0214] <3-3-1. Communication Environment> First, the communication environment assumed in the second embodiment will be described.

[0215] Fig. 18 is a diagram showing an example of a communication environment assumed in Example 2. In Example 2 as well, one or more propagation path control devices 30 are installed in an environment where one or more base stations 20 and multiple terminal devices 40 exist. In the example of Fig. 18, M propagation path control devices 30 are installed in an environment where one base station 20 and N terminal devices 40 exist. N and M are each any integer. The propagation path control device 30 is, for example, a RIS.

[0216] The propagation path control device 30 may be fixed or movable. In the second embodiment, a control station 50 controls a plurality of propagation path control devices 30. In the example of Fig. 18, the control station 50 controls M propagation path control devices 30. Here, the control station 50 may control the propagation path control devices 30 by transmitting control information to the propagation path control devices 30.

[0217] Each of the multiple terminal devices 40 is connected to the base station 20. The communication between the multiple terminal devices 40 is controlled by a scheduler of the base station 20. In the second embodiment, as an example, it is assumed that communication is performed using a time division multiple access (TDMA) method. That is, in the second embodiment, the base station 20 allocates radio resources to the multiple terminal devices 40 over time. Of course, the connection method is not limited to the TDMA method, and may be a frequency division multiple access (FDMA) method or a code division multiple access (CDMA) method. Furthermore, the connection method may be a combination of multiple different connection methods.

[0218] In the second embodiment, the propagation path control device 30 is not connected to the base station 20 or the terminal device 40. The propagation path control device 30 is controlled by a scheduler independent of these communication devices. In the second embodiment, the control station 50 has a control function (scheduler) for the propagation path control device 30.

[0219] The control station 50 may be one of the multiple propagation path control devices 30, or may be a control device (for example, the control unit 33) included in the propagation path control device 30. In this case, the following description of the control station 50 can be replaced with the propagation path control device 30 or the control unit 33.

[0220] 3-3-2. Communication Processing Next, a description will be given of communication processing according to the second embodiment. Fig. 19 is a sequence diagram showing communication processing according to the second embodiment.

[0221] In the second embodiment, the multiple propagation path control devices 30 are also Blind RISs. Note that the propagation path control devices 30 may be devices that can control propagation paths other than RISs. The term "propagation path control device 30" that appears in the following description can be replaced with "RIS," "IRS," "IS," "metasurface," "smart surface," "intelligent surface," "metamaterial," or "relay device."

[0222] In the example of Fig. 19, the BS is a base station 20, RIS#1 to RIS#M are propagation path control devices 30, and UE#1 to UE#N are terminal devices 40. In this sequence example, one base station 20 performs wireless communication with each of multiple terminal devices 40 (UE#1 to UE#N). Of course, multiple base stations 20 may exist. Below, communication processing according to the second embodiment will be described with reference to the sequence diagram of Fig. 19.

[0223] First, the control station 50 determines the communication devices (base stations 20 and / or terminal devices 40) that are to be controlled for the propagation path (step S401). Here, the control station 50 determines, for each of the multiple propagation path control devices 30, the communication devices that are supported by the propagation path control device 30. In the following description, the communication devices that are to be controlled for the propagation path may be referred to as supported communication devices. Furthermore, in the following description, of the supported communication devices, the communication devices that transmit signals may be referred to as transmitting devices, and the communication devices that receive signals may be referred to as receiving devices.

[0224] The control station 50 may determine the communication device to be supported based on information observed by itself (for example, information sensed by the sensor unit 54 of the control station 50). The control station 50 may also acquire information observed by another device (for example, information sensed by the sensor unit 54 of the propagation path control device 30) and determine the communication device to be supported based on the acquired information.

[0225] The method for determining the communication device to be supported may be the same as the method shown in the first embodiment (for example, the method described using FIGS. 13 and 14 ). For example, the control station 50 may determine the communication device to be supported based on whether there is a line of site (LOS) between at least one of the plurality of propagation path control devices 30 and the communication device. The control station 50 may also determine the communication device to be supported based on the observation results of an incoming wave to at least one of the plurality of propagation path control devices 30. Alternatively, the control station 50 may determine the communication device to be supported using the method shown in the first embodiment. In this case, the description of the propagation path control device 30 shown in the first embodiment can be replaced with the control station 50 as appropriate.

[0226] Each of the multiple propagation path control devices 30 may determine the communication devices that it supports. Then, each of the multiple propagation path control devices 30 may transmit the determination results to the control station 50. At this time, each of the multiple propagation path control devices 30 may determine the communication devices to be supported by the method shown in the first embodiment (for example, the method described using FIGS. 13 and 14 ). For example, the propagation path control device 30 may determine the communication devices to be supported based on whether there is a line of site (LOS) between the communication device and the propagation path control device 30. Furthermore, the propagation path control device 30 may determine the communication devices to be supported based on the observation results of the incoming waves. Furthermore, the propagation path control device 30 may determine the communication devices to be supported based on information acquired from another device. For example, the propagation path control device 30 may determine the communication devices to be supported based on information sensed by the sensor unit 54 of the control station 50, or may determine the communication devices to be supported based on information sensed by the sensor unit 54 of another propagation path control device 30. Alternatively, the propagation path control device 30 may determine the communication device to be supported by the method shown in the first embodiment.

[0227] The control station 50 may remove a communication device that satisfies a specific condition from the list of supported communication devices. For example, if the movement speed of the communication device satisfies a predetermined standard, for example, if the movement speed of the communication device is faster than a predetermined speed, the control station 50 may remove the communication device from the list of supported communication devices.

[0228] The method for determining the communication devices to be supported is not limited to the above method. For example, the control station 50 may determine the communication devices to be ultimately supported based on the determination results of the control station 50 and the determination results of the propagation path control device 30. Of course, the control station 50 may use other methods to determine the communication devices to be supported.

[0229] For example, the control station 50 may determine the communication devices to be supported based on the results of monitoring control information exchanged between communication devices (for example, DCI exchanged between the base station 20 and the terminal device 40). For example, the propagation path control device 30 may identify one or more terminal devices 40 connected to a specific base station 20 (specific cell) by observing the DCI. Then, the propagation path control device 30 may determine one or more terminal devices 40 connected to the specific base station 20 (specific cell) as the communication devices to be supported. This allows the control station 50 to support communications limited to the terminal devices 40 connected to the specific base station 20 (specific cell).

[0230] When the control station 50 controls a plurality of propagation path control devices 30, the control station 50 may decide which communication device to assign to which propagation path control device 30. At this time, the control station 50 may decide the assignment based on information acquired from the propagation path control device 30. For example, suppose that the same terminal device 40 is listed as a candidate for support by a plurality of propagation path control devices 30. In this case, the control station 50 may assign the terminal device 40 to the propagation path control device 30 that has a large effect of improving the propagation characteristics for the terminal device 40. Of course, the control station 50 may assign the same terminal device 40 to a plurality of propagation path control devices 30. In this case, the control station 50 may switch the operation mode of the propagation path control device 30. For example, the control station 50 may switch the operation mode of the propagation path control device 30 from a mode in which the propagation path control device 30 operates independently to a mode in which a plurality of propagation path control devices 30 operate in cooperation with each other.

[0231] The control station 50 may determine the allocation of the communication device taking into consideration the moving speed of the communication device. For example, if there is a difference in performance among a plurality of propagation path control devices 30, the control station 50 may allocate the communication device to a propagation path control device 30 that can track the moving speed of the terminal device 40. In this case, the control station 50 may determine the moving speed of the communication device based on the Doppler frequency and / or the direction of arrival of the radio waves, or may determine the moving speed based on information from an optical device (imaging device) such as a camera and / or an optical sensor.

[0232] 19 , the control station 50 determines a schedule for forming a reflection pattern or a transmission pattern for each of the plurality of propagation path control devices 30 (step S402). At this time, the control station 50 may determine the schedule by allocating a time for forming a reflection pattern or a transmission pattern to each of the plurality of communication devices (e.g., the plurality of terminal devices 40) based on a predetermined standard.

[0233] For example, the control station 50 may allocate a formation time of a reflection pattern or a transmission pattern to a plurality of communication devices (e.g., a plurality of terminal devices 40) based on a PF rule (Proportional Fair rule, Proportional Fair Scheduling, Proportional Fair Sharing). For example, the control station 50 may calculate fairness according to a specific index for each communication device, and allocate a formation time of a reflection pattern or a transmission pattern to each communication device so that the fairness improves. The index of fairness may be at least one of throughput, MCS, reception SNR, reception SINR, and rank index.

[0234] The predetermined criterion is not limited to the PF criterion. The control station 50 may allocate the formation times of reflection patterns or transmission patterns to multiple communication devices so as to improve (e.g., maximize / minimize) a specific index. For example, the control station 50 may allocate the formation times of reflection patterns or transmission patterns to each communication device so as to improve the lowest or highest index among multiple indexes (e.g., two or more indexes selected from throughput, MCS, received SNR, received SINR, and rank index).

[0235] Furthermore, the predetermined standard may be a standard based on information related to communication (reflected or transmitted signals). For example, the control station 50 may allocate a time for forming a reflection pattern or a transmission pattern according to the purpose or priority of the communication. For example, the communication may be prioritized according to the requirements of network design. The control station 50 may prioritize the communication based on control information exchanged between communication devices (for example, DCI exchanged between the base station 20 and the terminal device 40). Then, the control station 50 may allocate a time for forming a reflection pattern or a transmission pattern to each communication device according to the priority.

[0236] When there are multiple communication devices with the same priority (e.g., communication devices with the same communication purpose), the control station 50 may allocate the formation times to those communication devices equally in a round-robin format, or may allocate the formation times based on a specific rule. The specific rule may be the same as the predetermined rule described above. For example, the control station 50 may allocate the formation times of the reflection pattern or transmission pattern to those communication devices based on the PF rule, or may allocate the formation times of the reflection pattern or transmission pattern to those communication devices so as to improve (e.g., maximize / minimize) a specific index.

[0237] In addition, when specific legal regulations require restrictions on interference, it is assumed that communication for a specific purpose may be prioritized from the viewpoint of interference protection. The control station 50 may preferentially allocate the formation time of the reflection pattern or the transmission pattern to the communication device that performs communication for the specific purpose.

[0238] Alternatively, the control station 50 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a specific communication device. Furthermore, the control station 50 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a communication device with a low throughput, MCS, reception SNR, reception SINR, or rank index. Furthermore, the control station 50 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a communication device with a high traffic volume. Furthermore, the control station 50 may preferentially allocate the formation time of a reflection pattern or a transmission pattern to a communication device with a high QoS requirement. Furthermore, the control station 50 may equally allocate the formation time of a reflection pattern or a transmission pattern to a plurality of communication devices in a round-robin format.

[0239] The operation unit of the scheduler of the control station 50 may be the operation unit of the scheduler of the base station 20 (for example, slot length), or may be the same time length as the Rank Index feedback period of MIMO communication, or may be the same time length as the MCS change interval (for example, 10 to 100 ms). Here, the operation unit of the scheduler is, for example, the allocation unit of the formation time of a reflection pattern or a transmission pattern.

[0240] Note that, when the operation unit of the scheduler of the control station 50 is adjusted to match the operation unit (e.g., slot length) of the scheduler of the base station 20, the schedule of the control station 50 needs to follow the schedule of the base station 20 to some extent. This increases the difficulty of scheduling. Therefore, the control station 50 may use a multiple slot length (e.g., 1 to 10 ms) as the schedule operation unit.

[0241] Note that multiple propagation path control devices 30 may each determine their own schedule. For example, multiple propagation path control devices 30 may each allocate a time for forming a reflection pattern or a transmission pattern to one or more communication devices allocated to that device. In this case, the control station 50 may adjust the schedule of each of the multiple propagation path control devices 30.

[0242] 19 , once the schedule is determined, the control station 50 transmits information about the schedule to the plurality of propagation path control devices 30 (step S403). The content of the information to be transmitted may be different for each propagation path control device 30. Each of the plurality of propagation path control devices 30 repeatedly executes its own schedule (step S404).

[0243] The control station 50 may update the determined schedule at a predetermined timing (step S405). For example, the control station 50 may update the schedule at a fixed interval. For example, the control station 50 may update the schedule at an update interval set when the propagation path control device 30 is installed, or at an update interval specified by a standard. The schedule update interval is, for example, 1 to 60 minutes.

[0244] The control station 50 may also update the schedule when a predetermined condition is satisfied. For example, the control station 50 may update the schedule when a change in the communication environment is detected. For example, the control station 50 may update the schedule in at least one of the following cases: when a new communication device is detected, when a communication device to be controlled no longer communicates, and when the communication volume of the communication device to be controlled has changed from a predetermined standard.

[0245] Furthermore, the control station 50 may update the schedule based on a signal transmitted from another device (e.g., the management device 10, the base station 20, the propagation path control device 30, the terminal device 40, or another control station 50). For example, the control station 50 may update the schedule in at least one of the following cases: when a signal requesting re-setting of the schedule is received from another device; and when a signal requesting a change of the communication device to be supported is received from another control station 50.

[0246] Furthermore, the control station 50 may update (reset) the schedule when it is determined that its own schedule is not well reflected in the schedule of the base station 20. For example, the control station 50 may update (reset) the schedule when there is a significant mismatch between the destination of a signal transmitted by the base station 20 and the reflection pattern or transmission pattern scheduled by the control station 50. In this case, the control station 50 may change the schedule operation unit (e.g., r1, r2, or r3 shown in FIGS. 15 to 17) or the schedule operation period (e.g., P1 or P2 shown in FIGS. 15 to 17) so that its own schedule is more easily reflected in the base station 20.

[0247] For example, if the schedule time of the base station 20 for each terminal device 40 is short relative to the length of the time allocation of the control station 50 (for example, a schedule operation unit), the schedule is reset so as to shorten the length of the time allocation of the control station 50. Conversely, if the schedule time of the base station 20 for each terminal device 40 is long relative to the length of the time allocation of the control station 50 (for example, a schedule operation unit), the schedule is reset so as to lengthen the length of the time allocation of the control station 50.

[0248] The control station 50 may assign a plurality of different reflection patterns or a plurality of different transmission patterns to one propagation path control device 30 at the same time. For example, if the size of the surface section 35 of the first propagation path control device 30 is sufficiently large, a first reflection pattern or a first transmission pattern may be assigned to a part of the surface section 35 of the first propagation path control device 30, and a second reflection pattern or a second transmission pattern may be assigned to another part of the surface section 35 of the first propagation path control device 30. In this case, the control station 50 may determine the area of ​​the surface section 35 to be assigned to a predetermined reflection pattern or a predetermined transmission pattern based on the above-mentioned predetermined standard.

[0249] 19, when the schedule update is completed, the control station 50 transmits information about the updated schedule to the plurality of propagation path control devices 30 (step S406). Each of the plurality of propagation path control devices 30 repeatedly executes the updated schedule (step S407).

[0250] According to this embodiment, even if the control station 50 is not connected to a communication device (e.g., a base station 20) that schedules wireless communication, a good propagation path is formed for a specific communication device (e.g., a terminal device 40) at a specific timing in a specific period. As a result, the communication device (e.g., a base station 20) that schedules wireless communication determines a communication schedule (e.g., an uplink, downlink, and / or sidelink schedule) so as to communicate with the specific communication device (e.g., a terminal device 40) at that timing. In other words, the schedule of the control station 50 is reflected in the communication schedule of the communication device in an autonomous and decentralized manner. As a result, the reflection pattern or the transmission pattern is switched according to the communication schedule of the communication device, thereby achieving effective use of radio wave resources.

[0251] <<4. Modifications>> The above-described embodiment is merely an example, and various modifications and applications are possible.

[0252] For example, the propagation path control device 30 appearing in the above-described embodiment may be a reflecting plate / reflecting sheet capable of controlling reflection characteristics (e.g., reflection direction / reflectance, etc.), or may be a transmitting plate / transmitting sheet capable of controlling transmission characteristics (e.g., refraction direction).

[0253] Furthermore, in the above-described embodiment, the propagation path control device 30 is a device capable of controlling the reflection characteristics and / or transmission characteristics of a structure (e.g., the surface portion 35) that reflects and / or transmits incoming radio waves. However, the characteristics that the propagation path control device 30 can control are not limited to these. For example, the propagation path control device 30 may be configured to be capable of controlling the radiation angle (directivity) of reflected and / or transmitted radio waves. In this case, the schedule determined by the propagation path control device 30 or the control station 50 is not limited to a schedule related to a reflection pattern and / or a transmission pattern, but may also be a schedule related to a radiation pattern.

[0254] Here, the radiation pattern is a pattern related to the radiation of incoming radio waves (e.g., a conversion pattern of incoming waves or a formation / generation pattern of radiated waves). For example, the radiation pattern is a combination of configurations of metasurfaces (metasurface elements). Here, the configuration may be setting information for forming / generating radiated waves for each metasurface (e.g., information related to permittivity and / or permeability). Note that the radiation pattern may also be a waveform pattern of radiated waves formed by a combination of the configurations. Here, forming a reflection pattern refers to a state having intended radiation characteristics by a propagation path control device 30 (e.g., a RIS), for example, changing the permittivity and / or permeability of one or more metasurfaces (metasurface elements).

[0255] In the above-described embodiment, the surface unit 35 of the propagation path control device 30 can be considered as a structure capable of both reflecting and transmitting the incoming radio waves. For example, the surface unit 35 may be a structure configured with one or more elements capable of changing the reflection characteristics of the incoming radio waves and one or more elements capable of changing the transmission characteristics of the incoming radio waves.

[0256] Furthermore, in the above-described embodiments, the schedule determined by the propagation path control device 30 or the control station 50 can be considered as a schedule relating to both the reflection pattern and the transmission pattern. Note that the schedule determined by the propagation path control device 30 or the control station 50 is not limited to a schedule relating to at least one of the reflection pattern and the transmission pattern. The schedule determined by the propagation path control device 30 or the control station 50 may include a schedule for forming a radiation pattern.

[0257] Furthermore, in the above-described embodiment, the communication devices that communicate via the propagation path control device 30 (for example, the RIS) are the base station 20 and the terminal device 40, but the communication devices that communicate via the propagation path control device 30 are not limited to these. For example, the communication devices that communicate via the propagation path control device 30 may be the terminal device 40 and another terminal device 40, or the base station 20 and another base station 20. Of course, the communication devices may be other communication devices such as the management device 10 and the control station 50. In this case, the descriptions of the base station 20 and / or the terminal device 40 that appear in the above-described embodiment can be replaced with descriptions indicating other communication devices, as appropriate.

[0258] Furthermore, the radio waves that the propagation path control device 30 controls are not limited to radio waves output from communication devices that perform wireless communication (for example, the base station 20 and / or the terminal device 40). For example, the propagation path control device 30 may control radio waves reflected, transmitted, or emitted from another propagation path control device 30. In this case, the schedule determined by the propagation path control device 30 or the control station 50 may include not only a schedule corresponding to the communication device that performs wireless communication, but also a schedule corresponding to the other propagation path control device 30. The propagation path control device 30 may then repeatedly execute the schedule.

[0259] Furthermore, in the above-described embodiment, the control station 50 is a device different from the communication device (e.g., the base station 20 and / or the terminal device 40) that performs wireless communication. However, the control station 50 may be one of a plurality of communication devices that perform wireless communication. For example, the control station 50 may be the base station 20 or the terminal device 40. The control station 50 may also be a control device (e.g., the control unit 23 or the control unit 43) that is included in the communication device. The control station 50 may also be one of a plurality of propagation path control devices 30, or may also be a control device (e.g., the control unit 53) that is included in the propagation path control device 30. Of course, the control station 50 may also be a device dedicated to controlling the propagation path control device 30.

[0260] In the above-described embodiment, the control station 50 may perform part or all of the processing executed by the control unit 33 of the propagation path control device 30. For example, the control station 50 may control the surface unit 35 of the propagation path control device 30 (for example, switching between a reflection pattern, a transmission pattern, or a radiation pattern).

[0261] Furthermore, in the above-described embodiment, the propagation path control device 30 or the control station 50 determines a schedule by allocating a formation time of a reflection pattern or a transmission pattern to a plurality of communication devices (e.g., a plurality of terminal devices 40) based on a predetermined rule. Here, the predetermined rule is not limited to the rule described above. For example, the propagation path control device 30 or the control station 50 may allocate a formation time of a reflection pattern, a transmission pattern, or a radiation pattern to each of a plurality of communication devices (e.g., a plurality of terminal devices 40) based on the traffic of the communication devices. For example, the propagation path control device 30 or the control station 50 may allocate a longer formation time to a communication device with a higher communication volume. The propagation path control device 30 or the control station 50 may allocate a formation time of a reflection pattern, a transmission pattern, or a radiation pattern to each of a plurality of communication devices (e.g., a plurality of terminal devices 40) based on information about the bandwidth used by the communication devices for communication. For example, the propagation path control device 30 or the control station 50 may allocate a longer formation time to a communication device using a smaller bandwidth. Here, the bandwidth may be the bandwidth of a component carrier, the bandwidth of a subcarrier, or the bandwidth of a BWP.

[0262] Furthermore, the propagation path control device 30 may be configured to reflect, transmit, or emit radio waves of different frequency bands at the same time. In this case, the schedule determined by the propagation path control device 30 or the control station 50 may include not only a time-direction schedule but also a frequency-direction schedule. That is, the schedule information determined by the propagation path control device 30 or the control station 50 may be time-frequency matrix information. Here, the scheduling operation unit in the frequency axis direction may be the same as the scheduling operation unit in the frequency axis direction of the base station. For example, the scheduling operation unit in the frequency axis direction may be the subcarrier interval. Alternatively, the scheduling operation unit in the frequency axis direction may be the component carrier width or the BWP width.

[0263] The control device that controls the management device 10, base station 20, propagation path control device 30, terminal device 40, or control station 50 of this embodiment may be realized by a dedicated computer system or a general-purpose computer system.

[0264] For example, a program for executing the above-described operations is stored on a computer-readable recording medium such as an optical disk, a semiconductor memory, a magnetic tape, or a flexible disk and distributed. Then, for example, the program is installed on a computer and the above-described processing is executed to configure a control device. In this case, the control device may be a device (e.g., a personal computer) external to the management device 10, the base station 20, the propagation path control device 30, the terminal device 40, or the control station 50. Alternatively, the control device may be a device (e.g., a control unit 13, a control unit 23, a control unit 33, a control unit 43, or a control unit 53) internal to the management device 10, the base station 20, the propagation path control device 30, the terminal device 40, or the control station 50.

[0265] The communication program may also be stored in a disk device provided in a server device on a network such as the Internet, and may be downloaded to a computer. The above-described functions may also be realized by a combination of an operating system (OS) and application software. In this case, the components other than the OS may be stored on a medium and distributed, or may be stored in a server device and downloaded to a computer.

[0266] Furthermore, among the processes described in the above embodiments, all or part of the processes described as being performed automatically can be performed manually, or all or part of the processes described as being performed manually can be performed automatically using a known method. In addition, the information including the processing procedures, specific names, various data, and parameters shown in the above documents and drawings can be changed as desired unless otherwise specified. For example, the various information shown in each drawing is not limited to the information shown in the drawings.

[0267] Furthermore, the components of each device shown in the figure are conceptual functional components and do not necessarily have to be physically configured as shown in the figure. In other words, the specific form of distribution and integration of each device is not limited to that shown in the figure, and all or part of them can be functionally or physically distributed and integrated in any unit depending on various loads, usage conditions, etc.

[0268] The above-described embodiments can be combined as appropriate within the scope of the present invention without causing any inconsistency in the processing content. The order of the steps shown in the sequence diagrams or flowcharts of the present embodiment can be changed as appropriate.

[0269] Furthermore, for example, the present embodiment can also be implemented as any configuration that constitutes an apparatus or system, such as a processor as a system LSI (Large Scale Integration), a module using multiple processors, a unit using multiple modules, a set in which other functions are added to a unit, or the like (i.e., a configuration of a part of an apparatus).

[0270] The functions performed by the components described herein may be implemented in circuitry or processing circuitry programmed to perform the described functions. Here, the circuitry or processing circuitry may be a general-purpose processor, an application-specific processor, an integrated circuit, an ASIC (Application Specific Integrated Circuit), a CPU (a Central Processing Unit), conventional circuitry, and / or a combination thereof. Processors include transistors and other circuits. A processor may be considered to be circuitry or processing circuitry. A processor may also be a programmed processor that executes a program stored in a memory.

[0271] In this specification, a circuit, unit, or means may be hardware that is programmed to realize a described function or that performs a described function. The hardware may be any hardware disclosed in this specification or any hardware that is programmed to realize or known to perform the described function. If the hardware is a processor, which is considered a type of circuitry, the circuit, means, or unit may be a combination of hardware and software used to configure the hardware and / or processor.

[0272] Furthermore, for example, the present embodiment can be implemented as any configuration constituting an apparatus or system. For example, the present embodiment can be implemented as a processor as a system LSI (Large Scale Integration), a module using multiple processors, a unit using multiple modules, or a set in which a unit further has additional functions. In other words, the present embodiment can also be implemented as a part of the configuration of an apparatus.

[0273] The system LSI may also be referred to as an SOC (System on Chip). In other words, each of the above-described or later-described devices (e.g., the management device 10, the base station 20, the terminal device 40, and the control station 50) may be interpreted as a processor (e.g., a CPU) serving as a system LSI (e.g., SoC), or as a module using or constituting the processor. Additionally or alternatively, the present embodiment may be implemented by any configuration constituting a device or system (e.g., a modem chip (baseband chip) or an RF (Radio Frequency) unit, or a combination thereof). The RF unit may include at least one of an RF circuit and an RF front-end. In other words, each of the above-described or later-described devices may be interpreted as a modem chip (baseband chip) or an RF unit, or a combination thereof. Additionally or alternatively, each of the above-described or later-described devices may be interpreted as a module using or constituting a modem chip or an RF unit.

[0274] The modem chip performs signal processing for communications within a device (including the devices described above or below). The modem chip may have at least a modulator or demodulator function. The RF unit may have at least one of an RF transceiver (RF upconverter, RF downconverter), a power amplifier, and a low-noise amplifier function. The RF transceiver converts between baseband signals and RF frequencies. The power amplifier amplifies signals for transmission from an antenna. The low-noise amplifier amplifies weak signals received from the antenna. Additionally or alternatively, the RF unit (particularly, the RF front end) may include at least one of the above-mentioned power amplifier, low-noise amplifier, envelope tracker, filter, duplexer, multiplexer, antenna switch, and antenna tuner.

[0275] The combination of the modem chip and the RF unit may be referred to as a modem-RF system. At least a portion of the modem chip or the RF unit, or a combination thereof, may be included in a system LSI (e.g., SoC). For example, the processing performed by at least a portion of the modem chip or the RF unit, or a combination thereof (e.g., at least a portion of the MAC layer processing / PHY layer processing) may be realized by the system LSI. Here, the MAC layer processing or PHY layer processing may be at least a portion of the processing performed by the devices (e.g., the management device 10, the base station 20, the terminal device 40, and the control station 50) in the above-mentioned or later-described embodiments.

[0276] In this embodiment, a system refers to a collection of multiple components (devices, modules (components), etc.), regardless of whether all of the components are in the same housing. For example, multiple devices housed in separate housings and connected via a network, etc., and a single device in which multiple modules are housed in a single housing are both systems.

[0277] Furthermore, for example, this embodiment can have a cloud computing configuration in which one function is shared and processed jointly by a plurality of devices via a network.

[0278] <<5. Conclusion>> As described above, according to this embodiment, the communication system 1 includes a plurality of communication devices that communicate in a communication environment in which the propagation path control device 30 is installed, and the propagation path control device 30. The propagation path control device 30 is a RIS (i.e., a Blind RIS) that operates without cooperation with the plurality of communication devices. The propagation path control device 30 determines a schedule for forming a plurality of reflection patterns or a plurality of transmission patterns corresponding to a plurality of communication devices (e.g., a plurality of terminal devices 40), and repeatedly executes the determined schedule.

[0279] As a result, even if the propagation path control device 30 is not connected to a communication device (e.g., base station 20) that schedules wireless communication, a good propagation path is formed for a specific communication device (e.g., terminal device 40) at a specific timing in a specific cycle. As a result, the communication device (e.g., base station 20) that schedules wireless communication determines a communication schedule so as to communicate with the specific communication device (e.g., terminal device 40) at that timing. In other words, the schedule of the propagation path control device 30 is reflected in the communication schedule of the communication device in an autonomous and decentralized manner. As a result, the propagation path control device 30 can switch between a reflection pattern and a transmission pattern according to the communication schedule of the communication device, thereby achieving effective use of radio wave resources.

[0280] The communication system 1 may also include a plurality of communication devices that communicate in a communication environment in which a plurality of propagation path control devices 30 are installed, the plurality of propagation path control devices 30, and a control station 50 that centrally controls the plurality of propagation path control devices 30. The propagation path control device 30 is a RIS (i.e., a Blind RIS) that operates without cooperation with the plurality of communication devices. The control station 50 determines a schedule for forming a plurality of reflection patterns or a plurality of transmission patterns corresponding to the plurality of communication devices (e.g., a plurality of terminal devices 40). Each of the plurality of propagation path control devices 30 repeatedly executes the determined schedule under the control of the control station 50.

[0281] As a result, even if the control station 50 is not connected to a communication device (e.g., base station 20) that schedules wireless communication, a good propagation path is formed for a specific communication device (e.g., terminal device 40) at a specific timing in a specific cycle. As a result, the communication device (e.g., base station 20) that schedules wireless communication determines a communication schedule so that it communicates with the specific communication device (e.g., terminal device 40) at that timing. In other words, the schedule of the control station 50 is reflected in the communication schedule of the communication device in an autonomous and decentralized manner. As a result, the reflection pattern or the transmission pattern is switched according to the communication schedule of the communication device, thereby achieving effective use of radio wave resources.

[0282] Although the embodiments of the present disclosure have been described above, the technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present disclosure. Furthermore, components of different embodiments and modifications may be combined as appropriate.

[0283] Furthermore, the effects of each embodiment described in this specification are merely examples and are not intended to be limiting, and other effects may also be obtained.

[0284] The present technology may also be configured as follows. (1) A propagation path control device having a structure that reflects or transmits incoming radio waves and capable of controlling the reflection characteristics or transmission characteristics of the structure, the propagation path control device comprising: a determination unit that determines a schedule for forming a plurality of reflection patterns or a plurality of transmission patterns corresponding to a plurality of communication devices that perform wireless communication; and a propagation path control unit that repeatedly executes the schedule. (2) The propagation path control device according to (1), including a determination unit that determines the communication devices that are targets for propagation path control. (3) The propagation path control device according to (2), wherein the determination unit determines the communication devices that are targets for propagation path control based on whether there is a line of site (LOS) between the communication devices and the propagation path control device. (4) The propagation path control device according to (3), wherein the determination unit excludes communication devices moving at a speed faster than a predetermined speed from targets for control, even if there is a line of site (LOS) between the communication devices and the propagation path control device. (5) The propagation path control device according to (2), wherein the discrimination unit discriminates a communication device to be a control target of a propagation path based on whether or not the communication device is a control target of another propagation path control device. (6) The propagation path control device according to (2), wherein the discrimination unit discriminates a communication device to be a control target of a propagation path based on a monitoring result of control information transmitted by the communication device. (7) The propagation path control device according to any one of (1) to (6), wherein the determination unit updates the schedule at a predetermined timing. (8) The propagation path control device according to (7), wherein the determination unit updates the schedule at regular intervals. (9) The propagation path control device according to (7), wherein the determination unit updates the schedule when a communication environment changes. (10) The propagation path control device according to (9), wherein the determination unit updates the schedule in at least one of the following cases: when a new communication device is detected, when a communication device to be controlled stops communicating, and when the communication volume of the communication device to be controlled has changed from a predetermined standard.(11) The propagation path control device according to any one of (1) to (10), wherein the determination unit determines the schedule by allocating formation times of the reflection pattern or the transmission pattern to the plurality of communication devices based on a predetermined rule. (12) The propagation path control device according to (11), wherein the determination unit allocates formation times of the reflection pattern or the transmission pattern to the plurality of communication devices based on a PF rule (Proportional Fair rule). (13) The propagation path control device according to (11), wherein the determination unit allocates formation times of the reflection pattern or the transmission pattern to the plurality of communication devices according to the purpose or priority of the wireless communication. (14) The propagation path control device according to any one of (1) to (13), wherein the determination unit allocates formation times of the reflection pattern or the transmission pattern to the plurality of communication devices using a multiple slot length, a rank index feedback period in MIMO communication, or an MCS change interval as an allocation unit. (15) The propagation path control device according to any one of (1) to (14), wherein the propagation path control device is a RIS (Reconfigurable Intelligent Surface) that operates without cooperating with the multiple communication devices. (16) A control device for controlling a propagation path control device that has a structure that reflects or transmits incoming radio waves and is capable of controlling the reflection characteristics or transmission characteristics of the structure, the control device comprising: a decision unit that decides a schedule for forming multiple reflection patterns or multiple transmission patterns corresponding to multiple communication devices that perform wireless communication; and a control unit that controls the propagation path control device to repeatedly execute the schedule. (17) The control device according to (16), wherein the propagation path control device is a RIS (Reconfigurable Intelligent Surface) that operates without cooperating with the multiple communication devices. (18) The control device according to (16) or (17), wherein the control device is a control station that centrally controls multiple propagation path control devices.(19) A method for controlling a propagation path by a propagation path control device having a structure that reflects or transmits incoming radio waves and capable of controlling the reflection characteristics or transmission characteristics of the structure, the control method comprising: determining a schedule for forming a plurality of reflection patterns or a plurality of transmission patterns corresponding to a plurality of communication devices that perform wireless communication; and repeatedly executing the schedule. (20) A method for controlling one or more propagation path control devices having a structure that reflects or transmits incoming radio waves and capable of controlling the reflection characteristics or transmission characteristics of the structure, the control method comprising: determining a schedule for forming a plurality of reflection patterns or a plurality of transmission patterns corresponding to a plurality of communication devices that perform wireless communication; and controlling the propagation path control device to repeatedly execute the schedule.

[0285] REFERENCE SIGNS LIST 1 Communication system 10 Management device 20 Base station 30 Propagation path control device 40 Terminal device 50 Control station 11, 31, 51 Communication unit 21, 41 Wireless communication unit 12, 22, 32, 42, 52 Storage unit 13, 23, 33, 43, 53 Control unit 34, 54 Sensor unit 35 Surface unit 211, 411 Transmission processing unit 212, 412 Reception processing unit 213, 413 Antenna 331, 531 Acquisition unit 332, 532 Discrimination unit 333, 533 Determination unit 334, 534 Propagation path control unit

Claims

1. A propagation path control device having a structure that reflects or transmits incoming radio waves and capable of controlling the reflection or transmission characteristics of the structure, comprising: a determination unit that determines a schedule for forming multiple reflection patterns or multiple transmission patterns corresponding to multiple communication devices that perform wireless communication; and a propagation path control unit that repeatedly executes the schedule.

2. The propagation path control device according to claim 1, further comprising a determination unit that determines the communication device that is the target of propagation path control.

3. The propagation path control device according to claim 2, wherein the discrimination unit discriminates the communication device to be the control target of the propagation path based on whether or not there is a line of site (LOS) between the communication device and the propagation path control device.

4. The propagation path control device according to claim 3, wherein the discrimination unit excludes from control targets any communication device moving at a speed faster than a predetermined speed, even if the communication device is in LOS (Line Of Site) with the propagation path control device.

5. The propagation path control device according to claim 2, wherein the discrimination unit discriminates the communication device to be controlled for the propagation path based on whether or not the communication device is under the control of another propagation path control device.

6. The propagation path control device according to claim 2, wherein the determining unit determines the communication device to be the control target of the propagation path based on the result of monitoring control information transmitted by the communication device.

7. The propagation path control device according to claim 1, wherein the determination unit updates the schedule at a predetermined timing.

8. The propagation path control device according to claim 7, wherein the determination unit updates the schedule at regular intervals.

9. The propagation path control device according to claim 7, wherein the determination unit updates the schedule when the communication environment changes.

10. The propagation path control device according to claim 9, wherein the decision unit updates the schedule in at least one of the following cases: when a new communication device is detected, when the communication device to be controlled ceases to communicate, and when the communication volume of the communication device to be controlled changes from a predetermined standard.

11. The propagation path control device according to claim 1, wherein the determination unit determines the schedule by allocating formation times of the reflection patterns or the transmission patterns to the plurality of communication devices based on a predetermined standard.

12. The propagation path control device according to claim 11, wherein the determination unit allocates the formation times of the reflection patterns or the transmission patterns to the plurality of communication devices based on a PF (Proportional Fair) rule.

13. The propagation path control device according to claim 11, wherein the determination unit allocates the formation time of the reflection pattern or the transmission pattern to the plurality of communication devices according to the purpose or priority of the wireless communication.

14. The propagation path control device according to claim 1, wherein the determination unit allocates the formation time of the reflection pattern or the transmission pattern to the plurality of communication devices using a multiple slot length, a rank index feedback period in MIMO communication, or an MCS change interval as an allocation unit.

15. The propagation path control device according to claim 1, wherein the propagation path control device is a RIS (Reconfigurable Intelligent Surface) that operates without cooperation with the plurality of communication devices.

16. A control device for controlling a propagation path control device that has a structure that reflects or transmits incoming radio waves and is capable of controlling the reflection or transmission characteristics of the structure, the control device comprising: a determination unit that determines a schedule for forming multiple reflection patterns or multiple transmission patterns corresponding to multiple communication devices that perform wireless communication; and a control unit that controls the propagation path control device to repeatedly execute the schedule.

17. The control device according to claim 16, wherein the propagation path control device is a RIS (Reconfigurable Intelligent Surface) that operates without cooperation with the plurality of communication devices.

18. The control device according to claim 16, wherein the control device is a control station that centrally controls a plurality of the propagation path control devices.

19. A method for controlling a propagation path using a propagation path control device that has a structure that reflects or transmits incoming radio waves and is capable of controlling the reflection or transmission characteristics of the structure, the method comprising: determining a schedule for forming multiple reflection patterns or multiple transmission patterns corresponding to multiple communication devices that perform wireless communication; and repeatedly executing the schedule.

20. A control method for one or more propagation path control devices that have a structure that reflects or transmits incoming radio waves and that can control the reflection or transmission characteristics of the structure, the control method comprising: determining a schedule for forming multiple reflection patterns or multiple transmission patterns corresponding to multiple communication devices that perform wireless communication; and controlling the propagation path control devices to repeatedly execute the schedule.

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