Communication apparatus, communication system, communication method, and non-transitory storage medium

Abstract

The invention provides a communication apparatus, a communication system, a communication method, and a non-transitory storage medium. A communication device is provided with an NTN communication unit configured to be connected to a non-terrestrial network, a sensor unit, and a control unit. The control unit is configured as follows: using the sensor unit to acquire presence information pertaining to the presence range of an obstruction in a space including the direction in which radio waves come or the direction in which the radio waves come when communicating by the NTN communication unit; a process is executed on the basis of a transmission / reception range in which radio waves can be transmitted and received between the NTN communication unit and the non-terrestrial network in the space, said transmission / reception range being estimated from the acquired presence information.

Description

Technical Field

[0001] The present disclosure relates to a communication device, a communication system, a communication method, and a non-transitory storage medium. Background Art

[0002] In the past, a technology for switching a wireless link for a communication terminal between a ground base station and a satellite base station has been studied. In this technology, when a ground base station in a disaster area stops and only a satellite base station can be used, the satellite base station preferentially establishes a wireless link for the communication terminal in the disaster area (for example, see Japanese Patent Application Laid-Open No. 2022-134676). Japanese Patent Application No. 2022-545100, Japanese Patent Application No. 2006-133215, and 3GPP (registered trademark) TR38.821V16.2.0 (2023-03) (Release 16) disclose related technologies. Summary of the invention

[0003] However, wireless stations of non-terrestrial networks (NTNs) including satellite base stations, high altitude platform stations (HAPS), etc. may be blocked by obstructions and cannot be used. An aspect of the disclosed embodiment improves the accuracy of predicting the availability of wireless stations in NTNs.

[0004] The first disclosed method is exemplified by a communication device. The communication device includes an NTN communication unit configured to be connected to a non-terrestrial network, a sensor unit, and a control unit. The control unit is configured to: obtain, using the sensor unit, existence information related to the existence range of an obstruction in a space including the transmission direction or arrival direction of a radio wave when communicating using the NTN communication unit; and perform processing based on a transceiverable range in space in which radio waves can be sent and received between the NTN communication unit and the non-terrestrial network, the transceiverable range being estimated by the obtained existence information.

[0005] The communication device may be mounted on a mobile body, and the control unit may be configured to estimate the transceiveable range in a time interval from a current time point to a future time point after a predetermined time has passed, based on the movement of the mobile body.

[0006] The communication device may also include a TN communication unit configured to be connected to a terrestrial network, and the control unit may also be configured to receive the position or position prediction information of the NTN wireless station in the space via the terrestrial network in advance, reflect the position or the position prediction information received in advance, and infer the receivable range.

[0007] The control unit may be configured to estimate the transceiveable range based on the presence information acquired from a device that performs a sensing process or an information processing apparatus that accumulates information collected in the past by the device.

[0008] The control unit may be configured to estimate the transmittable / receivable range based on information acquired from the information processing device and real-time information acquired from the equipment.

[0009] The control unit may be configured to switch between communication using the NTN communication unit and communication using the TN communication unit based on the estimated transmittable / receivable range.

[0010] The control unit may be configured to use both communication using the NTN communication unit and communication using the TN communication unit.

[0011] The control unit may be configured to estimate the transmittable / receivable range based on a rainfall condition in the space.

[0012] A second disclosed aspect provides a communication system including the communication device and the non-terrestrial network.

[0013] The third disclosed method is exemplified by a communication method. The communication method includes: a computer obtains existence information related to the existence range of an obstruction in a space including an outgoing direction or an incoming direction of a radio wave when communicating using an NTN communication unit configured to be connected to a non-terrestrial network; and the computer performs processing based on a transceiveable range in the space in which the radio wave can be sent and received between the NTN communication unit and the non-terrestrial network, the transceiveable range being estimated by the obtained existence information.

[0014] The NTN communication unit may be mounted on a mobile body, and the communication method may further include: estimating the transceiveable range in a time interval from a current time point to a future time point after a predetermined time has passed, moment by moment, based on the movement of the mobile body.

[0015] The communication method may further include: receiving the position or position prediction information of the NTN wireless station in the space in advance via a ground network; and reflecting the position or the position prediction information received in advance to estimate the transceiveable range.

[0016] The communication method may further include estimating the transceiveable range based on the presence information acquired from a device that performs a sensing process or an information processing apparatus that accumulates information collected in the past by the device.

[0017] The estimation may also include: estimating the transceiveable range based on information obtained from the information processing device and real-time information obtained from the equipment.

[0018] The communication method may further include switching between communication using the NTN communication unit and communication using a TN communication unit configured to be connected to the terrestrial network, based on the estimated transceiveable range.

[0019] The communication method may further include: using the communication using the NTN communication unit and the communication using the TN communication unit configured to be connected to the terrestrial network in combination.

[0020] The communication method may further include: estimating the transmittable and receivable range based on a rainfall condition in the space.

[0021] The fourth disclosed method is a non-transitory storage medium storing commands that can be executed by one or more processors and cause the one or more processors to perform the following functions: obtaining existence information related to the existence range of an obstruction in a space including the transmission direction or arrival direction of a radio wave when communicating using an NTN communication unit configured to be connected to a non-terrestrial network; and performing processing based on a transceiveable range in the space where the radio wave can be transmitted and received between the NTN communication unit and the non-terrestrial network, the transceiveable range being estimated by the obtained existence information.

[0022] The communication device can improve the accuracy of prediction of the availability of wireless stations in the NTN. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and in which:

[0024] Figure 1 This is a diagram illustrating an environment in which a vehicle equipped with the communication device according to the first embodiment travels.

[0025] Figure 2 The diagram exemplifies a vehicle equipped with a communication device and a group of devices associated with the communication device.

[0026] Figure 3 This is a diagram illustrating a structure included in a network.

[0027] Figure 4 It is a diagram illustrating the structure of a communication device.

[0028] Figure 5 It is a diagram illustrating the structure of an information processing device.

[0029] Figure 6 This is a diagram illustrating a movement path in which LOS prediction and determination processing is performed using a communication device.

[0030] Figure 7 This is a flowchart illustrating a communication method using the communication device mounted on the vehicle according to the first embodiment.

[0031] Figure 8 : is a flowchart illustrating the details of the LOS prediction process.

[0032] Fig. 9 This is a flowchart illustrating the processing of the communication device according to the second embodiment.

[0033] Fig.10 This is a flowchart illustrating the processing of the communication device according to the third embodiment.

[0034] Fig.11 This is a flowchart illustrating the details of the LOS and communication quality prediction processing according to the third embodiment. DETAILED DESCRIPTION

[0035] Hereinafter, the communication device 30, the communication system 100, the communication method, the non-transitory storage medium, and the program according to the present embodiment will be described with reference to the accompanying drawings. The communication device 30 includes an NTN communication unit 39 that can be connected to a non-terrestrial network, a sensor 38, and a control unit (see Figure 1 , Figure 2 , Figure 4 The control unit uses the sensor 38 to obtain the existence information related to the existence range of the obstruction in the space including the transmission direction or the arrival direction of the radio wave when communicating using the NTN communication unit 39. In addition, the control unit performs processing based on the transceiveable range of the radio wave that can be sent and received between the NTN communication unit 39 and the non-terrestrial network in the space, which is estimated based on the obtained existence information. In addition, in the space including the transmission direction or the arrival direction of the radio wave, there is an NTN wireless station 6 that is a connection destination of the non-terrestrial network.

[0036] The communication device 30 can be moved, for example, by being mounted on a mobile body or being carried by a user. Therefore, it is assumed that the above-mentioned existence information changes with the movement of the communication device 30. Therefore, the present control unit repeatedly and momentarily predicts the movement path of the communication device 30 in the time interval from the current time point to a future time point after a predetermined time. The present control unit obtains existence information related to the existence range of the obstruction in the movement path of the communication device 30 in the time interval until the future time point. The communication device 30 can also infer the existence information through its own information processing. The communication device 30 can also obtain the existence information from the NTN communication unit 39 or the TN communication unit ( Figure 4The information processing device 4, the database 7, etc. on the network N1 connected to the communication IF33) (refer to Figure 1 , Figure 4 ) accept the provision of this existence information. First Embodiment

[0037] System Structure

[0038] Below, refer to Figures 1 to 8 , a vehicle 3 as a moving body according to the first embodiment, a communication device 30 mounted on the vehicle 3, and a communication system 100 including the communication device 30 are illustrated. Figure 1 1 is a diagram illustrating an environment in which vehicles 3A and 3B equipped with the communication device 30 of the first embodiment are traveling. In addition, vehicles 3A, 3B, etc. are collectively referred to as vehicles 3. Vehicle 3 may also be an autonomous driving vehicle. The vehicles 3 included in the communication system 100 may be one or more than three. In addition, the mobile object is not limited to a four-wheeled vehicle, but may also be a motorcycle, a bicycle, etc. In addition, the mobile object may be a ship or a flying object that can move in space, such as a flying device called a drone or an airplane. As Figure 1 As shown, a communication device 30 according to the present embodiment is mounted on a vehicle 3 as a moving object.

[0039] exist Figure 1 In the paper, the line of sight is also called the depth direction. Figure 1 In , the direction opposite to the line of sight facing the paper is also called the front direction. Figure 1 In the figure, there is a mountain m1 far away in the depth direction. The vehicle 3A is traveling on the left lane RL1 of the road from the front side to the depth direction of the drawing. On the other hand, the vehicle 3B is traveling on the right lane RL2 of the road from the depth side to the front side of the drawing.

[0040] In addition, near the road where the vehicle 3A is traveling on the front side of the drawing, there are shielding objects m2 on both sides of the road. On the other hand, near the road where the vehicle 3B is traveling on the depth side of the drawing, shielding objects m2 are intermittent, and the space where the field of vision can be widened is larger than near the road where the vehicle 3A is traveling. Moreover, an NTN wireless station 6 is illustrated above the distant mountain m1.

[0041] The NTN wireless station 6 is a communication satellite, HAPS, etc., and carries an NTN communication device 60. The communication satellite includes a geosynchronous orbit (GSO) satellite and a non-geosynchronous orbit (NGSO) satellite.

[0042] The NTN wireless station 6 communicates with a terrestrial communication device 30 or a user equipment (UE) 2 (see Figure 3 ) connection. In the case where the NTN wireless station 6 is a GSO satellite, the service link can be provided by a beam of radio waves that is fixed to the earth and always covers the same geographical area. On the other hand, in the case where the NTN wireless station 6 is a satellite other than a GSO satellite, the service link can be provided by a beam of radio waves of the quasi-Earth-fixed type or the Earth-moving type.

[0043] Here, in the beam of radio waves of the Earth-moving type, the cell in NTN (hereinafter referred to as NTN cell) moves on the ground when the NTN wireless station 6 (NGSO satellite, etc.) moves on the orbital plane. Here, the NTN cell refers to the communicable range covered by one NTN wireless station 6 at a certain point in time. In addition, in the Quasi-Earth-fixed type, different beams for each period remain stationary for a certain period of time on a given NTN cell on the ground. The profile of each beam based on the ground surface is called a coverage area. The beam of radio waves of the Quasi-Earth-fixed type can be formed using the NTN wireless station 6 that generates a steerable beam in order to fix the coverage area on the ground for a certain period of time.

[0044] The NTN communication device 60 mounted on the NTN wireless station 6 connects the ground communication device 30, UE2, etc. to a mobile communication system such as a 5G core network (5GC). In addition, in each of the following embodiments, an application example of applying the communication system 100 to a fifth-generation mobile communication system is illustrated. However, the communication system 100 of this embodiment can also be applied to a mobile communication system of the fourth generation or fifth generation or later.

[0045] The NTN communication device 60 connects the ground communication device 30, UE2, etc. to the mobile communication system through transparent relay or regenerative relay. In "transparent relay", the waveform of the relayed wireless signal is not changed. On the other hand, in regenerative relay, demodulation, decoding, switching, routing, encoding and modulation of the wireless signal are performed. Therefore, the NTN communication device 60 and the NTN wireless station 6 that perform regenerative relay can carry all or part of the functions of the ground base station such as the next generation Node B (gNB) on a communication satellite or HAPS, etc.

[0046] The NTN communication device 60 is connected to the ground NTN gateway via a communication line called a feeder link. In transparent relaying, the NTN gateway connects the NTN communication device 60 to the ground base station (gNB, etc.) of the mobile communication system. On the other hand, in regenerative relaying, the NTN gateway can also directly connect the NTN communication device 60 to the core network (5GC, etc.) of the mobile communication system without passing through the ground base station (gNB, etc.).

[0047] Figure 2 2 is a diagram illustrating a vehicle 3 equipped with a communication device 30 according to the present embodiment and a group of devices associated with the communication device 30. Figure 2 In the figure, as a group of devices associated with the communication device 30, a user equipment (UE) 2, an information processing device 4, a database 7, and an NTN wireless station 6 connected to a network N1 including a mobile communication system are exemplified. The network N1 includes, for example, mobile communication systems such as Long Term Evolution (LTE), the fifth generation mobile communication system (5G), and the sixth generation mobile communication system (6G), a wireless local area network (LAN), etc. Figure 2 In the figure, for example, a solid line illustrates a wired communication line, and a dotted line illustrates a wireless communication line.

[0048] UE2 is a device called a mobile terminal, a smart phone, etc. UE2 accesses the network N1 via a base station included in the network N1. In addition, UE2 can also access the network N1 via a communication line called a service link and the NTN wireless station 6.

[0049] The communication device 30 has the same structure as the UE 2 and performs the same processing. However, the communication device 30 and the sensor 38 on the vehicle 3 (see Figure 4) connection. The communication device 30 uses the sensor 38 to detect whether there are any obstructions in the surrounding space on the moving path of the vehicle 3. Furthermore, the communication device 30 obtains the orbit information (Ephemeris information) of the NTN wireless station 6 from the network N1 via the NTN wireless station 6 or directly from the network N1 without passing through the NTN wireless station 6. The orbit information includes, for example, time (date hour minute second, Epoch), position (X, Y, Z) in the center of the earth, earth-fixed (ECEF) orthogonal coordinates, and speed (dX / dt, dY / dt, dZ / dt). However, the orbit information may also be coordinates and speed in polar coordinates (phi, lambda, a, b) of an ellipsoid. Here, for example, a is the equatorial radius of the ellipsoid, b is the polar radius passing through the two poles of the ellipsoid, phi is the latitude, and lambda is the longitude. In addition, the orbit information may also be the True Equator Mean Equinox (TEME) coordinates.

[0050] The communication device 30 obtains orbital information from the NTN wireless station 6 or the base station of the wireless access network connected to the network N1. For example, when the communication device 30 is connected to the LTE or 5G core network (5GC), the orbital information can be obtained through the System Information Block (SIB). 3GPP (registered trademark) 38.331 specifies the process for the communication device 30 (and UE2) to obtain the SIB from the 5GC. In addition, the communication device 30 obtains the orbital information of the currently connected NTN wireless station 6 from the network N1 and the orbital information of the NTN wireless station 6 covering the candidate NTN cell to which the communication device 30 is connected at a predetermined time ΔT.

[0051] In the present embodiment, the information processing device 4 acts as a server managing the orbital information of all NTN wireless stations 6 or a database storing information, similar to the Assisted-GlobalPositioning System (A-GPS), and provides the orbital information of the NTN wireless station 6. Therefore, by inquiring the information processing device 4 through the communication device 30, the orbital information of the NTN wireless station 6 covering the NTN cell that becomes the candidate for connection of the communication device 30 at the predetermined time ΔT can be obtained. However, the server managing the orbital information of all NTN wireless stations 6 or the database storing information is not limited to the information processing device 4.

[0052] For example, a mobile communication system included in the network N1 may be managed and provided (see Figure 3) connects the server managing the track information of all NTN wireless stations 6 or the database holding the information to DN5. In addition, the server managing the track information of all NTN wireless stations 6 or the database holding the information can also be set to be accessible from the communication device 30. Figure 3 AF12. In addition, it can also be used as Figure 3 One of the functions of NEF11e is to provide the track information of all NTN wireless stations 6. Furthermore, in the communication standards such as 5G and 6G, the provision of such track information may be stipulated as one of the functions of NF11 such as NEF11e. In this way, the communication device 30 inquires the information processing device 4, other servers or databases about "NTN wireless stations that exist in the time period before and after a certain time near the designated location (current location, future location)".

[0053] The communication device 30 determines a transceiveable range (Line Of Sight (LOS)) within which radio waves can be transmitted and received between the communication device 30 and the NTN wireless station 6 on the moving path based on obstacles on the moving route and the track information of the NTN wireless station 6 .

[0054] The communication device 30 is equipped with a sensor 38. The sensor 38 is, for example, a radar, a camera, or a sensor that detects a signal from the communication IF 33 (see Figure 4 ) is a receiver for detecting reflected waves from obstructions of electromagnetic waves radiated by the vehicle 3. For example, the sensor 38 has a laser irradiation device and a light detector capable of scanning in a two-dimensional plane in front of the vehicle 3. The sensor 38 detects obstructions in front of the vehicle 3 by scanning in a two-dimensional plane in front of the vehicle 3 with a laser and receiving reflected light. The sensor 38 may also be a three-dimensional millimeter wave radar that combines a transmitter that irradiates a plurality of pencil beams in front of the vehicle 3 and a receiver that receives reflected waves from the front of the vehicle 3 in a gain pattern of a plurality of pencil beams. The transmitter may also be a communication IF33 (see Figure 4 ). Therefore, the sensor 38 detects three-dimensional existence information about the existence range of the obstruction in front of and around the vehicle 3 on the moving path of the vehicle 3.

[0055] The sensor 38 may also be a device having a processor and a camera, and taking an image in front of the vehicle 3. The processor may recognize an obstruction in front of the vehicle 3 from the image taken by the camera, and notify the communication device 30 of information such as the height and depth of the obstruction as seen from the vehicle 3.

[0056] The communication device 30 may obtain a 3D MAP around the vehicle 3 from the database 7 connected to the network N1. The communication device 30 may add the existence information about the existence range of the obstruction detected by the sensor 38 to the 3D MAP information obtained from the database 7 to determine the LOS.

[0057] The communication device 30 may also predict the LOS from the present moment to a predetermined time ΔT in the future. For example, the communication device 30 updates the 3DMAP information around the vehicle 3 every moment based on the current position information, driving speed, acceleration, driving direction, destination, and information related to the obstruction detected by the sensor 38 of the vehicle 3, and estimates the LOS. The communication device 30 may also pass the current position information, driving speed, acceleration, driving direction, destination, and information related to the obstruction detected by the sensor 38 of the vehicle 3 to the information processing device 4, and entrust it to calculate the LOS from the present moment to a predetermined time ΔT in the future.

[0058] The information processing device 4 provides LOS calculation services to the communication device 30 and UE2, etc. For example, together with the current position information, driving speed, acceleration, driving direction, destination, and information related to the obstruction detected by the sensor 38, the information processing device 4 receives a commission from the communication device 30, etc. to calculate the LOS from the current time point to the predetermined time ΔT in the future. At this time, the information processing device 4 obtains the orbit information of the NTN wireless station 6 to which the communication device 30 is currently connected and the orbit information of the NTN wireless station 6 covering the candidate cell to which the communication device 30 and UE2 are connected at the predetermined time ΔT from its own storage device 42. However, as described above, the information processing device 4 can also obtain the above-mentioned orbit information from a server, database, etc. connected to the DN5 of the 5GC. In addition, the information processing device 4 can also obtain the above-mentioned orbit information from a server, database, etc. provided by the AF12 as the 5GC.

[0059] As described above, in this embodiment, the information processing device 4 performs processing as a server that manages the track information of all NTN wireless stations 6 or a database that maintains the information. Therefore, the information processing device 4 may also be a server or the like that can receive a request from the communication device 30 and respond to "NTN wireless stations that exist in the time period before and after the designated time near the designated location (current location, future location)".

[0060] The information processing device 4 may also obtain the 3DMAP in the moving path from the current position of the communication device 30 to the destination from the database 7. However, the information processing device 4 may also store the 3DMAP in the moving path of the communication device 30 in the storage device 42 (see Figure 5) and reads out. The information processing device 4 may also be, for example, a DN5 (see Figure 3 ) connected to the computer. In addition, the information processing device 4 may also be, for example, AF12 of 5GC (refer to Figure 3 ).

[0061] The database 7 updates the 3DMAP information on the ground and provides the latest 3DMAP information to the communication device 30 and UE2. 3DMAP is a three-dimensional map information that adds vertical (height and depth) information to the two-dimensional map information. The database 7 collects three-dimensional information around the communication device 30 and UE2, etc., together with the two-dimensional position information of each device from the communication device 30 and UE2 connected to the network N1 and other devices. The three-dimensional information can also be information based on images captured by cameras mounted on mobile bodies such as vehicles 3 and cameras mounted on UE2. The database 7 updates the 3DMAP information every moment based on the collected images or three-dimensional information. In addition, the database 7 provides the current 3DMAP information to the communication device 30 and UE2 in accordance with requests from the communication device 30 and UE2.

[0062] The database 7 stores information on 3DMAPs that rarely change over time in the storage device 42 (see Figure 4 ). Database 7 obtains the latest three-dimensional information around UE2 from UE2 connected to network N1, and updates 3DMAP. For example, database 7 obtains three-dimensional information such as the position, height, and width of a newly built building from UE2 connected to network N1. Such information can also be called real-time information. UE2 that provides real-time information can be called a device that performs sensing processing.

[0063] The database 7 can also be referred to as a computer that accumulates information collected by the device in the past. The database 7 can also be, for example, a DN5 (see Figure 3 ) connected to the computer. Database 7 may also be, for example, AF12 of 5GC (refer to Figure 3 ).

[0064] Figure 3 1 is a diagram illustrating a configuration of a mobile communication system included in a network N1. Figure 3 It can also be called a diagram illustrating components (constituent elements) constituting the fifth generation mobile communication system (also referred to as 5G network, 5G Network (NW)). However, as already described, the network N1 is not limited to the 5G network, but may also be an LTE network, or may be a network including a mobile communication system after 6G. Figure 3 In the example, UE2 is the terminal of the user (subscriber). Figure 4As an example, the communication device 30 also has the same structure as the UE 2. The radio access network (RAN) 3 is an access network to the 5G core network (5GC). The RAN 8 is composed of base stations (gNB).

[0065] The 5G network has a 5G core network (5GC) and an access network ((R)AN), and the above-mentioned UE2, data network (Data Network (DN)) 5, and application function (Application Function (AF)) 12 are connected to the 5G network. In addition, 5GC has NF11a~11e, 11g~11k (hereinafter referred to as NF11a~11k) represented by bold letters. NF11a~11k are functions implemented by executing programs by one or more computers. However, any two or more of NF11a~11k can also be implemented by a single computer. In addition, in this embodiment, the components of 5GC are collectively referred to as network functions (Network Function (NF)) 11. In addition, the components of 5GC are independently referred to as NEF11e, etc. Figure 3 In the drawings, for each component, an independent symbol is given in parentheses together with the symbol of the general term.

[0066] As described above, 5GC is composed of a collection of components having predetermined functions called NF11. Figure 3 In FIG. 5 , the following contents are illustrated as NF11 constituting 5GC. Figure 3 In the figure, NF11 is represented by a thick rectangle.

[0067] User Plane Function (UPF) 11a

[0068] Access and Mobility Management Function (AMF) 11b

[0069] SessionManagementFunction (SMF, session management function) 11c

[0070] PolicyControlFunction (PCF, Policy Control Function) 11d

[0071] NetworkExposureFunction (NEF, network exposure function) 11e

[0072] NetworkRepositoryFunction (NRF, network repository function) 11g

[0073] NetworkSliceSelectionFunction (NSSF, network slice selection function) 11h

[0074] AuthenticationServerFunction (AUSF, authentication service function) 11i

[0075] Unified Data Management (UDM) 11j

[0076] NetworkDataAnalyticsFunction (NWDAF, network data analysis function) 11k

[0077] In this embodiment, the user plane packets sent and received by UE2 are called user packets. UPF11a performs routing and forwarding of user packets, packet inspection, and QoS processing. AMF11b is an intra-regional accommodation device for UE2 in 5GC. AMF11b accommodates RAN8 and performs subscriber authentication control, location (mobility) management of UE2, etc.

[0078] SMF11c manages the Protocol Data Unit (PDU) session and controls UPF11a to implement Quality of Service (QoS) control and policy control. The PDU session is a virtual communication path for exchanging data between UE2 and DN5. DN5 is a data network (Internet, etc.) outside 5GC.

[0079] PCF11d cooperates with SMF11c to perform QoS control, policy control, charging control, etc. In QoS control, communication quality control such as packet forwarding priority is performed. In policy control, communication control such as QoS based on network or subscriber information, packet forwarding permission, and charging is performed.

[0080] NEF11e mediates the communication between AF12 or nodes outside 5GC and NF11 of 3GPP (registered trademark). For example, NEF11e securely discloses the functions and events of each NF11 to third parties, AF12, edge computers, etc. NEF11e transforms internal information and external information of 5GC. For example, NEF11e transforms information handled by AF12 and information handled by each NF11 of 5GC. For example, NEF11e transforms the service identifier in AF12 and the internal information of 5GC.

[0081] AF12 is an element that interacts with 5GC to provide services to users, and is called an external application server, for example. AF12, which is considered reliable by the operator of the 5G network, can directly access the NF11 associated with 5GC. AF12, which is not allowed to directly access the NF11 associated with 5GC, uses the interface exposed to the outside through NEF11e to access the network functions of 5GC.

[0082] NRF11g stores and manages information about NF11 (such as AMF11b, SMF11c, UPF11a, etc.) in 5GC. NRF11g can send back multiple NF11 candidates to the source of the inquiry in response to an inquiry about the NF11 that is desired to be used.

[0083] NSSF11h has a function of selecting a network slice to be used by a subscriber from among network slices generated by network slicing. A network slice is a virtual network with specifications corresponding to the purpose.

[0084] AUSF11i is a subscriber authentication server that performs subscriber authentication under the control of AMF11b. UDM11j maintains or manages subscriber-related information. Subscriber-related information can be referred to as an example of contract data. Contract data is, for example, information based on a contract between a user of the communication device 30 (and UE2) and an operator (also referred to as an operator, a mobile network operator (MNO)) that manages a mobile communication system. UDM11j provides subscriber-related information to each NF11, or acquires, registers, deletes, or changes the status of UE2.

[0085] NWDAF11k has the function of collecting and analyzing data from each NF11, operations, administration, and maintenance (OAM) terminals, etc. Here, the OAM terminal operates / manages / maintains the network (5GC). In other words, NWDAF11k is the NF11 that provides analysis information of the network.

[0086] DN5 is a network outside the communication system, such as the Internet. DN5 is connected to the communication network provided by the present communication system (5GC) via one UPF11a. In addition, UPF11a can adopt a multi-level structure. The final level UPF11a connected to DN5 is called a PDU session anchor user plane function (PDUSession Anchor User Plane Function (PSAUPF)). In addition, the UPF11a set between RAN8 and PSAUPF is called an intermediate UPF (IntermediaryUPF (IUPF)).

[0087] exist Figure 3 In the example, the information processing device 4 and the database 7 are connected to DN5. Figure 2 Furthermore, in Figure 3 In the embodiment, LOS calculation AF12a and 3DMAPAF12b are provided at positions parallel to AF12. LOS calculation AF12a, as AF12, calculates LOS on the moving path of the user's device, that is, communication device 30, UE2, etc., and provides information of LOS as a calculation result to communication device 30, UE2, etc. That is, LOS calculation AF12a provides the same processing as information processing device 4. 3DMAPAF12b, as AF12, updates 3DMAP and provides it to communication device 30, UE2, LOS calculation AF12a, or information processing device 4. That is, 3DMAPAF12b provides the same processing as database 7.

[0088] Structure of information processing device and terminal

[0089] Figure 4 3 is a diagram illustrating the structure of a communication device 30. The communication device 30 is a device installed in a mobile body such as a vehicle 3 and accesses a mobile communication system, and has the same structure as the UE 2. The communication device 30 includes a processor 31 as a processing unit or a control unit (controller), a storage device 32, a communication interface 33 (communication IF33), an NTN communication unit 39, an input device 34, and a display 35, which are connected to each other via a bus 36. In addition, the communication device 30 may also be connected to a sensor 38 via an interface (referred to as I / F37). The sensor 38 is as shown in FIG. Figure 2 As described in the foregoing, for example, it is a radar, a camera, etc. In addition, the communication device 30 may use the transmitter of the communication IF 33 as a substitute for the transmitter of the sensor 38 .

[0090] The storage device 32 includes a main storage device and an auxiliary storage device. The main storage device is used as at least one of a storage area for programs and data, a program expansion area, a program operation area, and a buffer area for communication data. The main storage device is composed of a random access memory (Random Access Memory (RAM)) or a combination of RAM and a read-only memory (ReadOnly Memory (ROM)). The auxiliary storage device is used as a storage area for data and programs. In the auxiliary storage device, a non-volatile storage medium is applied. Non-volatile storage media are, for example, hard disks, solid state drives (Solid State Drive (SSD)), flash memory, or electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory (EEPROM)). In addition, the storage device 32 can include a drive device for a disk recording medium.

[0091] Communication IF33 is a circuit that performs communication processing. For example, communication IF33 is a transmitter and a receiver that accesses a base station (gNB) of a mobile communication system such as 5GC. In addition, for example, communication IF33 is a network interface card (NIC). In addition, communication IF33 may also be a wireless communication circuit that performs wireless communication (5G, wireless LAN (Wi-Fi (registered trademark)), Bluetooth (registered trademark) Low Energy (BLE) etc.). In addition, communication IF33 may also be a combination of a circuit that performs wired communication processing and a circuit that performs wireless communication processing. The NTN communication unit 39 is a transmitter and a receiver that communicates with the NTN wireless station 6 in the air via a service link.

[0092] The input device 34 includes keys, buttons, a pointing device, a touch panel, etc., and is used to input information. The display 35 is, for example, a liquid crystal display, an organic electro-luminescence (OEL) display, etc. The display 35 displays information and data.

[0093] Figure 5 is a diagram illustrating the structure of the information processing device 4. However, it can also be called Figure 5The structures of NF11a~11k, AF12, LOS calculation AF12a, 3DMA AF12b, and database 7 are illustrated. The information processing device 4 can be configured using a dedicated or general-purpose computer such as a personal computer (PC), a workstation (WS), or a server machine. The information processing device 4 can also be a collection of one or more computers (cloud). The information processing device 4 includes a processor 41, a storage device 42, a communication interface 43 (communication IF43), an input device 44, and a display 45 that are interconnected via a bus 46. The processor 41, the storage device 42, the communication IF43, the input device 44, and the display 45 can use the same structure as the processor 31, the storage device 32, the communication IF33, the input device 34, and the display 35. Therefore, their description is omitted.

[0094] The processors 31 and 41 perform various processes by executing various programs stored in the storage devices 32 and 42. The processors 31 and 41 are, for example, central processing units (CPU). The CPU is also called a microprocessor unit (MPU). The processors 31 and 41 can be either a single processor structure or a multi-processor structure. In addition, a single physical CPU connected to a single socket can also have a multi-core structure. The processors 31 and 41 can also include computing devices of various circuit structures such as a digital signal processor (DSP) or a GPU (Graphics Processing Unit). In addition, the processors 31 and 41 can also have a structure that cooperates with at least one of an integrated circuit (IC), other digital circuits, and analog circuits. Integrated circuits include LSIs, application specific integrated circuits (ASICs), and programmable logic devices (PLDs). PLDs include, for example, field programmable gate arrays (FPGAs). The processors 31 and 41 also include, for example, what are called microcontrollers (MCUs), system-on-a-chip (SoCs), system LSIs, or chipsets.

[0095] Processing example

[0096] Figure 6 FIG. 4 is a diagram illustrating a moving path for performing LOS prediction and availability determination processing using the communication device 30. Figure 6, the coverage areas FP1 to FP8 illustrate the cross-section on the ground surface of the beam from the NTN wireless station 6 on the movement path of the vehicle 3 during the predetermined time ΔT. The NTN wireless station 6 may be, for example, a GSO satellite, an NGSO satellite, or a HAPS.

[0097] In the case where the NTN radio station 6 is an NGSO satellite or HAPS and provides an Earth-moving type service link, the coverage areas FP1 to FP8 move on the ground when the NTN radio station 6 moves on the orbital plane. In the case where the NTN radio station 6 is an NGSO satellite or HAPS and provides a Quasi-Earth-fixed type service link, the coverage areas FP1 to FP8 remain stationary for a certain time on the NTN cells at various locations. On the other hand, in the case where the NTN radio station 6 is a GSO satellite, the service link and the NTN cell are Earth-fixed, always covering the same area.

[0098] The communication device 30 uses, for example, the SIB to obtain the track information of the NTN wireless station 6 on the moving path for a predetermined time ΔT from the current position of the vehicle 3 at all times. Figure 2 As described in , orbital information includes, for example, time (date hour minute second, epoch), Earth-centered, Earth-fixed (ECEF) orthogonal coordinates (X, Y, Z), and velocity (dX / dt, dY / dt, dZ / dt). However, orbital information may also be coordinates and velocity in ellipsoidal polar coordinates (phi, lambda, a, b).

[0099] The communication device 30 calculates the LOS on the moving path for the predetermined time ΔT from the current position of the vehicle 3 every moment or obtains it from the information processing device 4. Therefore, the communication device 30 determines the coverage areas FP1 to FP8 reflecting the LOS on the moving path for the predetermined time ΔT from the current position of the vehicle 3 every moment.

[0100] exist Figure 6 In the moving path illustrated by LOS1 on the left side, the coverage areas FP1 to FP5 reflecting LOS are all connected. That is, LOS1 is an example of no disconnection. In the example of LOS1, the communication device 30 determines that it can connect to the NTN wireless station 6 without disconnection on the moving path moving from the current position for a predetermined time ΔT.

[0101] On the other hand, Figure 6In the moving path illustrated by LOS2 on the right side, there is a disconnection location Z1 between the coverage areas FP6 and FP7. There is a disconnection location Z2 between the coverage areas FP7 and FP8. That is, LOS2 is an example of disconnection. In the example of LOS2, the communication device 30 determines that the connection with the NTN wireless station 6 is disconnected at the disconnection location Z1, Z2, etc. on the moving path moving for a predetermined time ΔT from the current position. The communication device 30 continues the communication with the network N1 by connecting to, for example, a base station on the ground just before reaching the disconnection location Z1, Z2.

[0102] Figure 7 2 is a flowchart illustrating a communication method using the communication device 30 mounted on the vehicle 3. This process is started, for example, when the power of the communication device 30 is turned on or the auxiliary power of the vehicle 3 is turned on. In this process, the communication device 30 repeatedly executes the communication method every predetermined time ΔT. Figure 7 The repetition starting from S1 is called LOOP1.

[0103] In LOOP1, the communication device 30 obtains the current time, the current location of the vehicle 3, the moving speed of the vehicle 3, etc. (S2). Next, the communication device 30 obtains the track information (position and moving speed) of the NTN wireless station 6, etc. that can be used in the section that can move at the obtained moving speed during the predetermined time ΔT (S3). For example, the communication device 30 obtains the position and moving speed of the NTN wireless station 6 that is currently connected. In the case where the wireless station of other NTN is around the NTN cell provided by the NTN wireless station 6 and provides the NTN cell on the moving path, the communication device 30 obtains the position and moving speed of the wireless station of other NTN. On the moving path means the path where the vehicle 3 moves at the moving speed obtained in S2 during the predetermined time ΔT. The moving path is a section where the connection of the NTN wireless station 6, etc. is predicted to be maintained, and is also called a predicted section. The NTN cell around the NTN cell provided by the NTN wireless station 6 is exemplified as the NTN cell that becomes the switching destination relative to the NTN cell provided by the NTN wireless station 6.

[0104] The NTN wireless station 6 and the wireless stations of the other NTNs mentioned above provide NTN cells that can be used on the moving path (prediction interval), and are referred to as NTN wireless stations 6, etc. In addition, the communication device 30 may also obtain the predicted position and predicted moving speed of the NTN wireless station 6, etc. in the future predicted within the predetermined time ΔT as the cycle of executing LOOP1 from the information processing device 4, the server or the database on the other network N1, in addition to the current position and moving speed of the current NTN wireless station 6, etc. at the current time point. In this way, the communication device 30 may also obtain the predicted predicted position of the NTN wireless station 6, etc. in the predetermined time ΔT as the LOS prediction period from the network N1 together with the current position of the NTN wireless station 6, etc., and store it in the storage device 32. The orbit information of the NTN wireless station 6, etc. as described above may be obtained from the NTN wireless station 6, etc., or may be obtained via a base station on the ground and a ground network. The communication device 30 performs repeated processing (S4) for each NTN wireless station 6, etc. that obtains the orbit information. This repetition is referred to as LOOP2.

[0105] The communication device 30 predicts the LOS to the NTN wireless station 6 at each point and time on the moving path (prediction interval) in the moving direction of the vehicle 3 (S5). Figure 8 , and the details of the processing of S5 are described in addition. Furthermore, the communication device 30 determines whether LOOP2 is completed (S6). That is, the communication device 30 determines whether LOOP2 is executed for all NTN wireless stations 6, etc. If LOOP2 is not completed, the communication device 30 returns the processing to S4 and continues LOOP2.

[0106] When LOOP2 ends, the communication device 30 determines whether the connection to the NTN wireless station 6 or the like is maintained within the predicted interval (S7). If the connection to the NTN wireless station 6 or the like is maintained within the predicted interval, the communication device 30 enables or maintains the NTN communication (S8). If the connection to the NTN wireless station 6 or the like is not maintained within the predicted interval, the communication device 30 enables the terrestrial network (TN) communication such as cellular communication or wireless LAN communication (S9). In this example, the communication device 30 switches from the NTN communication to the TN communication.

[0107] The communication device 30 determines whether LOOP1 has ended (S10). The end of LOOP1 refers to the case where the power of the communication device 30 is turned off or the auxiliary power of the vehicle 3 is turned off. If LOOP1 has not ended, the communication device 30 returns the process to S1 and continues LOOP1. If the power is turned off, the communication device 30 ends the process.

[0108] In addition, in the process of S9, the communication device 30 may use NTN communication together with TN communication. The reason for this is that the connection to the NTN wireless station 6 and the like is at least partially continued within the prediction interval. Here, the use of the NTN communication together means that the communication device 30 maintains the connection to the NTN wireless station 6 using the NTN communication unit 39, and the communication IF 33 as the TN communication unit maintains the connection to the base station on the ground. By using the NTN communication together in this way, the communication device 30 can switch to the TN communication in a short time even if the connection to the NTN wireless station 6 and the like is interrupted.

[0109] Figure 8 is an example of LOS prediction processing ( Figure 7 The communication device 30 performs repetition for each time interval Δt within a predetermined time ΔT as a LOS prediction period (k=0~N) (S51). The repetition for each time interval Δt is called LOOP3. The number of repetitions k=0 corresponds to the current moment, and ΔT=N*Δt. The time interval Δt is, for example, a time that can track the degree of change in LOS accompanying the movement of the vehicle 3. Instead of performing repetition for each time interval Δt, the communication device 30 may repeat the processing of LOOP3 for each NTN cell that overlaps with the movement path (prediction interval) during the predetermined time ΔT.

[0110] In LOOP3, for example, the communication device 30 predicts the position of the vehicle 3 at time k*ΔT (CX=CVx*Δt, CY=CVy*Δt) based on the speed of the vehicle 3 (S52). Here, (CVx, CVy) is the speed of the vehicle 3. Here, the origin (0, 0) of the position of the vehicle 3 is set as the current location. However, the communication device 30 may obtain the road conditions and congestion conditions of the current moving path from the vehicle navigation system or the like, and correct the speed of the vehicle 3.

[0111] The communication device 30 predicts the position of the NTN wireless station 6 etc. at the time k*ΔT (NX=NVx*Δt, NY=NVy*Δt, NZ=NVz*Δt) (S53) based on the current track information (time, position, speed) of the NTN wireless station 6 etc. Here, (NVx, NVy, NVz) is the speed of the NTN wireless station 6 etc.

[0112] The communication device 30 may read the location of the NTN wireless station 6 etc. from the storage device 32 instead of predicting the location of the NTN wireless station 6 etc. in S53. Figure 7The predetermined position of the NTN wireless station 6 etc. within the predetermined time ΔT obtained in advance in the process of S3. The orbit information (time, position, speed) of the NTN wireless station 6 etc. can also be expressed by polar coordinates (phi, lambda, a, b) of the ellipsoid. The communication device 30 determines the range of the NTN cell (or coverage area) provided by the beam of the NTN wireless station 6 etc. at the time k*ΔT.

[0113] The communication device 30 obtains the 3DMAP reflecting the obstruction at the position (CX, CY) of the vehicle 3 (S54). For example, the communication device 30 obtains the 3DMAP at the position of the vehicle 3 at the time k*ΔT from the database 7 via the network N1. Figure 7 When the current location of vehicle 3 is obtained in the processing of S2, 3DMAPs near the moving path (prediction interval) moved during the LOS prediction period ΔT are obtained in advance from the database 7. Furthermore, the communication device 30 can also obtain real-time information of 3DMAPs added to the moving path (prediction interval) from UE2 connected to the network N1. In addition, the communication device 30 can also obtain real-time information of 3DMAPs added to the moving path (prediction interval) from UE2 using a communication method called sidelink or new radio-vehicle (NR-V) 2XPC5, for example. The communication device 30 can also obtain real-time information of 3DMAPs added to the moving path (prediction interval) from other vehicles connected to the network N1 or other vehicles connected by vehicle-to-vehicle communication. Vehicle-to-vehicle communication uses, for example, sidelink or NR-V2XPC5. Real-time information refers to, for example, the existence of a crane temporarily installed for a building construction project. UE2 that provides real-time information can be called a device that performs sensing processing.

[0114] The communication device 30 uses the sensor 38 mounted on the vehicle 3 to detect obstacles around the vehicle 3 and in front of the vehicle 3 that are equivalent to the position of the vehicle 3 at time k*ΔT (CX=CVx*Δt, CY=CVy*Δt). Figure 2 It is explained in the figure that the sensor 38 is, for example, a radar, a camera, or a receiver that detects reflected waves from an obstruction of electromagnetic waves released from the communication IF 33. That is, it can be said that the communication device 30 uses the sensor 38 to obtain the existence information related to the existence range of the obstruction in the space including the transmission direction or arrival direction of the radio wave when communicating using the NTN communication unit 39.

[0115] The communication device 30 adds the information obtained from the UE2 connected to the network N1 and the existence information of the obstruction detected by the sensor 38 to the 3DMAP obtained from the database 7. In addition, the order of the above-mentioned S52, S53 and S54 is not limited, and any of them can be performed first. The above-mentioned S52, S53 and S54 can also be performed in parallel.

[0116] The communication device 30 calculates the LOS at the time k*ΔT (S55). That is, the communication device 30 obtains the spatial communicable range based on the 3DMAP obtained from the database 7, the information obtained from the UE2, and the information of the obstruction detected by the sensor 38. The communication device 30 reflects the position of the NTN wireless station 6 and the like at the time k*ΔT obtained in S53 to the spatial communicable range, and obtains the connectable range (LOS) with the NTN wireless station 6 in the space above the vehicle 3. The connectable range can also be referred to as a transceiver range in which radio waves can be sent and received between the communication device 30 and the NTN wireless station 6.

[0117] The communication device 30 reflects the LOS at the position corresponding to each time k*ΔT on the moving path (prediction interval) to the NTN cell (or coverage area) on the moving path. That is, the communication device 30 limits the NTN cell (or coverage area) of the NTN communication determined based on the position of the NTN wireless station 6, etc. to the range of the LOS specified by the existence of the shield. The range of the LOS is, for example, Figure 6 Illustrated coverage areas FP1 to FP8.

[0118] The communication device 30 determines whether LOOP3 has ended, that is, whether the repetition (k=0~N) of each time interval Δt has been completed (S58). If the repetition (k=0~N) has not been completed, the communication device 30 returns the process to S51. If the repetition (k=0~N) has been completed, the communication device 30 returns to Figure 7 processing (RETURN). Effects of implementation methods

[0119] As described above, according to the present embodiment, the communication device 30 includes the NTN communication unit 39 connectable to the non-terrestrial network, the sensor 38 as a sensor unit, and the processor 31 and the storage device 32 as a control unit.

[0120] The communication device 30 uses the sensor 38 to obtain the presence information about the range of the obstruction in the space including the transmission direction or the arrival direction of the radio wave when communicating using the NTN communication unit 39. In addition, the communication device 30 determines the LOS, which is the range of communication available in the space above and in front of the vehicle 3 and can be connected to the NTN wireless station 6, estimated from the obtained presence information. And the communication device 30 performs processing based on the LOS. Processing based on the LOS means that the communication device 30 tries its best not to interrupt the processing, for example, Figure 7 That is, the communication device 30 can maintain the communication with the network N1 as much as possible while performing the communication using the NTN communication unit 39.

[0121] The communication device 30 is mounted on a mobile body such as a vehicle 3. The communication device 30 estimates the LOS for each time interval Δt in the time interval from the current time point to the future time point after a predetermined time ΔT according to the movement of the vehicle 3 etc. at all times. The communication device 30 performs either or both of the NTN communication and the TN communication according to the estimated LOS. That is, the communication device 30 can maintain communication with the network N1 as much as possible while using the movement of the vehicle 3 etc.

[0122] The communication device 30 includes a communication IF 33 as a TN communication unit that can be connected to a ground network. The communication device 30 can receive the position or position prediction information of the NTN wireless station 6 in space in advance via the ground network. In addition, the communication device 30 reflects the received position or position prediction information of the NTN wireless station 6 and estimates the LOS. The communication device 30 can stably obtain the position or position prediction information of the NTN wireless station 6 in space through the ground network together with the NTN communication and estimate the LOS.

[0123] The communication device 30 estimates the LOS based on the information obtained from the UE2 as a device performing the sensing process or the existence information obtained from the database 7 that accumulates the information collected by the UE2 in the past. Therefore, the LOS can be estimated based on the information that changes over time in addition to the information of the 3DMAP (information of the database 7) that changes less over time. The information obtained from the UE2 includes real-time information. That is, the communication device 30 can estimate the LOS based on the three-dimensional information that changes in real time in addition to the information of the 3DMAP that changes less over time stored in the database 7.

[0124] The communication device 30 switches between the communication using the NTN communication unit 39 and the communication using the communication IF 33 as the TN communication unit according to the estimation result. Therefore, the communication device 30 can stably implement the communication with the network N1 by using the NTN communication unit 39 and the TN communication unit (communication IF 33). The communication device 30 can realize more stable communication by using the communication using the NTN communication unit 39 and the communication using the communication IF 33 as the TN communication unit. The communication device 30 can continue to maintain the communication with the network N1 while judging the quality, connectivity, availability, etc. of the NTN communication in advance.

[0125] The sensor 38 does not need to be a camera. Therefore, the vehicle 3 or the communication device 30 can obtain information added to the 3DMAP without being equipped with a camera. The communication device 30 can obtain information added to the 3DMAP without the sensor 38 by cooperating with other vehicles or UE2. However, it is sufficient to decide whether the vehicle 3 is equipped with a sensor 38 or a camera based on the trade-off between processing time, estimation accuracy, communication quality, and cost. Second Embodiment

[0126] Reference Fig. 9 , the communication device 30 involved in the second embodiment is described. In the above-mentioned first embodiment, the communication device 30 determines whether the connection to the NTN wireless station 6 or the like is maintained within the prediction interval. And, in the case where the connection to the NTN wireless station 6 or the like is maintained within the prediction interval, the communication device 30 enables or maintains the NTN communication. On the other hand, in the case where the connection to the NTN wireless station 6 or the like is not maintained within the prediction interval, the communication device 30 enables TN communication such as cellular communication or wireless LAN communication. In addition, in this case, the communication device 30 uses both NTN communication and NT communication.

[0127] In this embodiment, in addition to the above processing, the communication device 30 determines that it is completely impossible to connect to the NTN wireless station 6 etc. in the prediction interval. The processing of this embodiment other than the case where it is completely impossible to connect to the NTN wireless station 6 etc. is the same as that of the first embodiment.

[0128] Fig. 9 2 is a flowchart illustrating the processing of the communication device 30 according to the second embodiment. Fig. 9 In the process of S1 to S6, Figure 7The same, so the description thereof is omitted. In the present embodiment, after LOOP2 ends, the communication device 30 determines whether it is completely impossible to connect to the NTN wireless station 6, etc. within the predicted interval (S11). If it is completely impossible to connect to the NTN wireless station 6, etc. within the predicted interval ("Yes" in S11), the communication device 30 enables TN communication (S12). If it is possible to connect to the NTN wireless station 6, etc. within the predicted interval ("No" in S11), the communication device 30 determines whether the connection to the NTN wireless station 6 is maintained without interruption within the predicted interval (S13). If the connection to the NTN wireless station 6 is maintained without interruption ("Yes" in S13), the communication device 30 enables or maintains NTN communication (S14). If the connection to the NTN wireless station 6, etc. is at least partially not maintained within the predicted interval ("No" in S13), the communication device 30 uses both TN communication such as cellular communication or wireless LAN communication and NTN communication (S15). The processing of S10 is the same as Figure 7 The situation is the same, so the description is omitted.

[0129] As described above, according to the present embodiment, the communication device 30 determines that within the prediction interval, the NTN communication is not interrupted but is completely maintained, partially maintained, or not maintained at all. Therefore, when the NTN communication is not maintained at all, the communication device 30 can take measures as soon as possible. When the NTN communication is partially maintained, the communication device 30 can use the NTN communication to the extent possible, and when the NTN communication is interrupted, it can quickly switch to the TN communication. In addition, the processing of S15 can also be combined with the processing of the first embodiment. Figure 7 Similarly, S9 in FIG. 1 is a process for simply activating TN communication. Third Embodiment

[0130] Below, refer to Fig.10 as well as Fig.11 , the communication device 30 involved in the third embodiment is described. In the above-mentioned first embodiment and second embodiment, the communication device 30 determines the LOS which is the communicable range in which the communication device 30 and the NTN wireless station 6 can be connected in the space around and in front of the vehicle 3. The communication device 30 switches between the NTN communication and the TN communication or uses the NTN communication and the TN communication in combination according to whether the connection with the NTN wireless station 6 is maintained within the predicted interval.

[0131] In this embodiment, the sensor 38 mounted on the vehicle 3 detects rainfall or the like in the range of LOS, and the communication device 30 estimates the communication quality in the range of LOS based on the detection result. In addition, a processing example in which the communication device 30 performs switching between NTN communication and TN communication or using NTN communication and TN communication in combination according to the communication quality is described. The processing of the third embodiment other than the detection of rainfall or the like in the range of LOS, the estimation of the communication quality in the range of LOS, and the switching between NTN communication and TN communication or using NTN communication in combination according to the communication quality is the same as that of the first and second embodiments.

[0132] Fig.10 3 is a flowchart illustrating the processing of the communication device 30 according to the third embodiment. In this processing, the processing of S1 to S4, S6 and S7 is the same as that of the first embodiment. Figure 7 In this embodiment, before entering the iterative process of LOOP2, the communication device 30 obtains the rainfall information in the sky within the prediction interval (S3A). The communication device 30 obtains the rainfall information from, for example, a base station on the ground, a weather server connected to AF12 or DN5, etc. (hereinafter referred to as a weather server, etc.).

[0133] In this embodiment, a base station, a meteorological server connected to AF12 or DN5, etc. are connected to a radar rain gauge via a network N1 to detect the rainfall situation. The radar rain gauge of this embodiment, for example, radiates electromagnetic waves of far infrared light in the terahertz frequency band, i.e., a frequency of approximately 100 GHz to 10 THz and a wavelength of 3 mm to 30 microns, into space. Moreover, the radar rain gauge detects clouds, raindrops, precipitation, etc. based on its reflection through the same structure as a conventional precipitation observation radar. The radar rain gauge can also be set at a base station on the ground, for example. In addition, the meteorological server, etc. can also obtain rainfall information from computers of public institutions such as the Ministry of Construction and the Meteorological Bureau, and computers of private weather forecasting companies, etc.

[0134] For example, in "Specifications and Applications of Radar Rain Gauges" by Kazuhiko Fukami, the River Information Center (FRICS) R4 Annual River Technology Research Institute (URL: http: / / www.river.or.jp / kougi2022_6.pdf, retrieved on October 15, 2023), the structure of a radar rain gauge or precipitation observation radar is illustrated. However, in this document, the electromagnetic waves used are from the S band (wavelength 10 cm) to the X band (wavelength 3 m). On the other hand, the radar rain gauge of this embodiment transmits a terahertz frequency band and pulsed electromagnetic wave into space, and measures the raindrop size distribution and rainfall amount based on the power value and phase of the electromagnetic wave backscattered by rain clouds, raindrops, etc., or the change in polarization waves in the transmitted and received waves.

[0135] The weather server or the like divides the sky above the moving path of the vehicle 3 into predetermined blocks and calculates the rainfall per unit time of each grid. The grid is, for example, a rectangle of a predetermined size (e.g., a rectangle of 1 km in length and width to a rectangle of 10 km in length and width), and a reference point (e.g., the position of a corner) is specified by latitude and longitude. However, the weather server or the like can also add vertical height information to the grid. That is, the weather server or the like can also measure the rainfall within a predetermined height range. The communication device 30 delivers the current location of the vehicle 3 and the moving path from the current time point to the moving location after a predetermined time ΔT to the weather server or the like, and obtains the rainfall of the grid overlapping with the moving path.

[0136] In LOOP2, the communication device 30 calculates the LOS to the NTN wireless station 6 at each point in the moving direction and at each time, and also predicts the communication quality within the range of the LOS (S5A). Fig.11 , and further details of S5A are given.

[0137] In the determination of S7, if the connection to the NTN wireless station 6 or the like is maintained within the prediction interval, the communication device 30 determines whether the communication quality in the LOS satisfies the reference (S7A). Here, the communication quality is determined based on whether the bit error rate estimated depending on the weather such as rain exceeds the reference value.

[0138] If the communication quality satisfies the standard in the entire range of LOS, the communication device 30 enables or maintains NTN communication (S8). If the communication quality does not meet the standard in the prediction interval, the communication device 30 enables TN communication such as cellular communication or wireless LAN communication (S9). In addition, in the process of S9, the communication device 30 may use TN communication and NTN communication at the same time. The process of S10 is the same as Figure 7 The same, so the description is omitted.

[0139] Fig.11 This is an example of the LOS and communication quality prediction process of this embodiment ( Fig.10 In this process, the processes from S51 to S55 are the same as those in the first embodiment. Figure 8 The same, so the description is omitted.

[0140] In this embodiment, after calculating the LOS, the communication device 30 obtains the rainfall in the range of the LOS (S56). Fig.10 The communication device 30 estimates the communication quality in each mesh within the LOS range based on the rainfall in the mesh within the LOS range (S57).

[0141] The communication device 30, for example, has an attenuation value table that specifies the attenuation of electromagnetic waves for the transmission and reception frequency and the rainfall. The communication device 30 refers to the attenuation value table to obtain whether there is rainfall or rainfall in the NTN cell (or coverage area) in the current communication. In addition, the communication device 30 obtains whether there is rainfall or rainfall in the grid that overlaps with the prediction interval. Moreover, the communication device 30 refers to the attenuation value table based on the acquired rainfall and determines the communication quality in each grid that overlaps with the prediction interval.

[0142] For example, the communication device 30 can assume that the communication quality Q0 measured in the NTN cell (or coverage area) in the current communication is a result reflecting the rainfall. Therefore, the communication device 30 obtains the difference ΔRxy between the rainfall R0 in the grid overlapping with the NTN cell in the current communication and the rainfall Rxy in each grid overlapping with each NTN cell in the prediction interval. The communication device 30 corrects the current communication quality Q0 according to the difference Δ in rainfall, obtains the communication quality in each grid overlapping with each NTN cell in the prediction interval, and reflects it in the communication quality in each NTN cell. For example, the communication device 30 saves the communication quality in the prediction interval on the moving path in the storage device 32, etc. However, the communication device 30 may also save the maximum value, minimum value, average value, etc. of the communication quality in each grid overlapping with the prediction interval as the communication quality of each NTN cell overlapping with the prediction interval in the storage device 32, etc.

[0143] Instead of obtaining the rainfall for each grid, the communication device 30 may obtain the rainfall in the entire predicted section on the moving path from a weather server or the like. That is, the communication device 30 may also obtain an approximate value of the rainfall, assuming that the rainfall in the entire predicted section on the moving path is constant within a predetermined allowable accuracy, and calculate the communication quality. Figure 8 The same, so the description is omitted.

[0144] As described above, the communication device 30 of this embodiment estimates the LOS as the range in which radio waves can be transmitted and received based on the rainfall state in the space. Therefore, the communication device 30 estimates the LOS not only based on the existence of the shielding object but also based on the weather. Other Implementations

[0145] The above-mentioned embodiment is only an example, and the present disclosure can be implemented with appropriate changes within the scope of the gist thereof. In addition, the processes and units described in the present disclosure can be implemented in combination as long as no technical contradiction occurs.

[0146] Processing described as being performed by one device may be shared and executed by multiple devices. Alternatively, processing described as being performed by different devices may be executed by one device. In a computer system, it is possible to flexibly change what hardware structure (server structure) is used to implement each function.

[0147] The present disclosure can also be implemented by supplying a computer program that implements the functions described in the above embodiments to a computer, and one or more processors of the computer read out and execute the program. Such a computer program can be provided to the computer via a non-temporary computer-readable storage medium that can be connected to the system bus of the computer, or it can be provided to the computer via a network. Non-temporary computer-readable storage media include, for example, any type of disk, hard disk drive, optical disk (compact disc (CD))-read only memory (Read Only Memory (ROM)), digital versatile disk (Digital Versatile Disc (DVD)) disk, Blu-ray disk, etc.), read-only memory (ROM), random access memory (Random Access Memory (RAM)), erasable programmable read-only memory (ErasableProgrammable Read-Only Memory (EPROM)), electrically erasable programmable read-only memory (ElectricallyErasableProgrammable Read-Only Memory (EEPROM)), magnetic card, flash memory, or any type of medium suitable for storing electronic commands such as an optical card.

Claims

1. A communication device, characterized in that: include: The Non-Terrestrial Network is the NTN communication unit, which is configured to connect to the non-terrestrial network. Sensor Department; as well as Control Department, The control unit is composed of: Acquiring, by means of the sensor unit, existence information on an existence range of an obstruction in a space including an outgoing direction or an incoming direction of radio waves during communication by means of the NTN communication unit; as well as A process is executed based on a transceiveable range within which the radio waves can be transmitted and received between the NTN communication unit and the non-terrestrial network in the space, the transceiveable range being estimated based on the acquired existence information.

2. The communication device according to claim 1, characterized in that The communication device is mounted on a mobile object, and The control unit is configured to estimate the transceivable range in a time interval from a current time point to a future time point after a predetermined time has elapsed, based on the movement of the moving body.

3. The communication device according to claim 1, characterized in that The device further comprises a TN communication unit configured to be connected to a terrestrial network, wherein: The control unit is configured to receive the position or position prediction information of the NTN wireless station in the space in advance via the ground network, reflect the position or the position prediction information received in advance, and estimate the transceiveable range.

4. The communication device according to claim 1, characterized in that: The control unit is configured to estimate the transceivable range based on the presence information acquired from a device that performs a sensing process or an information processing apparatus that accumulates information collected in the past by the device.

5. The communication device according to claim 4, characterized in that: The control unit is configured to estimate the transmittable / receivable range based on the information acquired from the information processing device and the real-time information acquired from the equipment.

6. The communication device according to claim 3, characterized in that: The control unit is configured to switch between communication using the NTN communication unit and communication using the TN communication unit based on the estimated transmittable / receivable range.

7. The communication device according to claim 3, characterized in that: The control unit is configured to use both communication using the NTN communication unit and communication using the TN communication unit.

8. The communication device according to claim 1, characterized in that: The control unit is configured to estimate the transmittable / receivable range based on a rainfall condition in the space.

9. A communication system, characterized in that: include: The communication device according to claim 1; as well as The non-terrestrial network.

10. A communication method, characterized in that: include: The computer obtains existence information related to the existence range of the shielding object in the space including the transmission direction or arrival direction of the radio wave when communicating using the NTN communication unit configured to be connected to the non-terrestrial network; as well as The computer executes processing based on a transceiveable range within which the radio waves can be transmitted and received between the NTN communication unit and the non-terrestrial network in the space, the transceiveable range being estimated based on the acquired existence information.

11. The communication method according to claim 10, characterized in that: The NTN communication unit is mounted on a mobile body. The communication method further comprises: The computer estimates the transceivable range in a time interval from a current time point to a future time point after a predetermined time has passed, based on the movement of the mobile body.

12. The communication method according to claim 10, characterized in that: Also includes: Receiving the location or location prediction information of the NTN wireless station in the space in advance via the ground network; as well as The position received in advance or the position prediction information is reflected to estimate the transceiveable range.

13. The communication method according to claim 10, characterized in that: Also includes: The transceivable range is estimated based on the presence information acquired from a device that performs sensing processing or an information processing apparatus that accumulates information collected in the past by the device.

14. The communication method according to claim 13, characterized in that: The speculations include: The transceivable range is estimated based on the information obtained from the information processing device and the real-time information obtained from the device.

15. The communication method according to claim 12, characterized in that: Also includes: Based on the estimated transceiveable range, communication using the NTN communication unit and communication using the TN communication unit configured to be connected to the terrestrial network are switched.

16. The communication method according to claim 12, characterized in that: Also includes: The communication using the NTN communication unit and the communication using the TN communication unit configured to be connected to the terrestrial network are used in combination.

17. The communication method according to claim 10, characterized in that: Also includes: The transmit-receive range is estimated based on the rainfall status in the space.

18. A non-transitory storage medium storing instructions that can be executed by one or more processors and cause the one or more processors to perform the following functions: Acquiring existence information on an existence range of an obstruction in a space including an outgoing direction or an incoming direction of a radio wave when communicating using an NTN communication unit configured to be connected to a non-terrestrial network; and A process is executed based on a transceiveable range within which the radio waves can be transmitted and received between the NTN communication unit and the non-terrestrial network in the space, the transceiveable range being estimated based on the acquired existence information.

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