Communication system, program, and communication method

Abstract

To provide a communication system, a program, and a communication method that can ensure the reliability of wireless communication even when a communication environment changes.SOLUTION: A communication system 100 includes a route information acquisition unit 104 that acquires planned route information, a base station information acquisition unit 105 that acquires base station information, a threshold acquisition unit 107 that acquires a switching threshold for received radio wave strength to execute switching to an HO destination base station, an HO prediction area acquisition unit 108 that acquires an HO prediction area, an arrival time prediction unit 109 that predicts the scheduled arrival time when its own vehicle 81 will arrive at the HO prediction area, a received radio wave strength prediction unit 110 that predicts the received radio wave strength of radio waves from a base station 72 in the HO prediction area before arriving at the HO prediction area, and an output processing unit 112 that generates and outputs mobile communication support information based on the comparison result between the predicted received radio wave strength and a switching threshold R0.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a communication system, a program, and a communication method. [Background technology]

[0002] Conventionally, there are known technologies for wirelessly communicating various data with the outside in order to execute various vehicle functions such as autonomous driving. For example, Patent Document 1 describes a technology for determining whether to continue autonomous driving based on communication status information when communication with an autonomous driving assistance center is interrupted. Furthermore, Patent Document 2 describes a technology for, when there is a data gap, generating assistance data by complementing the data gap with previously received information and outputting the data to a driving assistance device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-71753 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-173904 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technology of Patent Document 1 determines the communication status based on whether or not there is a communication interruption, and has the problem that it is not possible to grasp the deterioration of communication quality until a communication interruption occurs. In Patent Document 2, when data loss occurs, the data loss is compensated for and reliability is evaluated using data loss count information, which results in unreliable data transmission and reception and also has the problem that it is not possible to grasp the deterioration of communication quality until data loss occurs. Therefore, there is room for improvement in terms of ensuring communication reliability.

[0005] An object of the present invention is to provide a communication system, a program, and a communication method that can ensure the reliability of wireless communication even when the communication environment changes. [Means for solving the problem]

[0006] (1) A communication system is a communication system equipped with a wireless communication unit mounted on a mobile body and transmitting and receiving data to and from base stations via wireless lines, and includes: a route information acquisition unit that generates route information regarding a route along which the mobile body is scheduled to travel based on input information, and acquires the route information; a base station information acquisition unit that acquires base station information including location information of each of a plurality of base stations that cover the communication area of ​​the route included in the acquired route information; a threshold acquisition unit that acquires a switching threshold of received radio wave strength that causes the wireless communication unit to switch to a new base station to which the mobile body will connect; a handover predicted area acquisition unit that acquires, based on at least the location information, a handover predicted area in which a handover is predicted to occur on the route included in the route information, in which the wireless communication unit switches from a base station to which it is currently connected to another base station; an arrival time prediction unit that predicts the arrival time at which the mobile body will arrive in the handover predicted area; a received radio wave strength prediction unit that predicts the received radio wave strength of radio waves from the base station in the handover predicted area at the arrival time before the mobile body arrives in the handover predicted area; and an output processing unit that generates and outputs mobile communication support information based on a comparison result between the received radio wave strength predicted by the received radio wave strength prediction unit and the switching threshold.

[0007] (2) In the communication system described in (1), the output processing unit outputs information predicting a deterioration in communication quality between the wireless communication unit and the base station as the mobile communication support information when the predicted received radio wave strength is below the switching threshold.

[0008] (3) In the communication system described in (1) or (2), when the predicted received radio wave strength is equal to or less than the switching threshold, the output processing unit generates an avoidance route that avoids the handover predicted area, and outputs the generated avoidance route as the mobile communication support information.

[0009] (4) The communication system described in (3) further includes an in-vehicle sensor that detects movement information of the moving body and an outside-vehicle sensor that detects information indicating the situation around the moving body, and the output processing unit generates the avoidance route by taking into account the information detected by at least one of the in-vehicle sensor and the outside-vehicle sensor.

[0010] (5) The communication system described in any one of (1) to (4) further includes a function adjustment unit that limits a function of the mobile body executed by transmitting and receiving data to and from the outside via the wireless communication unit when the predicted received radio wave strength is below the switching threshold and it is necessary to limit the function.

[0011] (6) In the communication system described in (5), when the output processing unit outputs the mobile communication support information predicting the restriction of the function of the mobile body by the function adjustment unit, it outputs selection information as the mobile communication support information to allow the driver of the mobile body to select whether to continue or stop the restricted function.

[0012] (7) In the communication system described in (6), the mobile body is an autonomous vehicle, and the function adjustment unit changes the autonomous driving level when the function for which a restriction on the mobile body's function is predicted is a function related to autonomous driving, and the output processing unit outputs the change in the autonomous driving level as the mobile communication support information before the function adjustment unit changes the autonomous driving level.

[0013] In the communication system described in (8)(7), the output processing unit outputs, as the mobile communication support information, information to prompt the switching of the control mode of the moving body from automatic control to manual control when the function for which the function restriction is predicted is a collision safety function related to autonomous driving.

[0014] (9) The communication system described in any one of (1) to (8) includes an information processing device having the route information acquisition unit, the base station information acquisition unit, the threshold acquisition unit, the handover prediction area acquisition unit, the arrival time prediction unit, the received radio wave intensity prediction unit, and the output processing unit, and a communication device having the wireless communication unit that performs bidirectional communication with an external communication device and the information processing device.

[0015] (10) In the communication system described in (9), the information processing device is capable of communicating with the communication device, an in-vehicle sensor that detects movement information of the mobile body, an outside sensor that detects the surrounding conditions of the mobile body, and an input / output device that accepts input operations by the driver of the mobile body and outputs information to the driver, and generates the route information, predicts the handover prediction area, predicts the arrival time, and predicts the received radio wave strength from the base station in the handover prediction area based on information obtained from the communication device, the in-vehicle sensor, the outside sensor, and the input / output device.

[0016] (11) In the communication system described in (10), the input / output device accepts an input operation by the driver of a plurality of point information used in generating the route information by the information processing device, and transmits the information to the information processing device.

[0017] (12) In the communication system described in (11), the plurality of location information includes a departure point and a destination point of the mobile object.

[0018] (13) In the communication system described in (11), the plurality of location information includes a departure point of the mobile body, a destination, and a stop-off point where the mobile body stops before traveling from the departure point to the destination.

[0019] (14) In the communication system described in (11), the plurality of location information includes a current location of the mobile body, a first evacuation point as an evacuation point for the mobile body to make an emergency stop in the event of an abnormality, and a second evacuation point that is an evacuation point different from the first evacuation point.

[0020] (15) The program is a program to be executed by a computer of a communication system that is mounted on a mobile body and has a wireless communication unit that transmits and receives data to and from base stations via wireless lines, and that generates route information regarding a route along which the mobile body is scheduled to travel based on input information, and includes a route information acquisition step for acquiring the route information, a base station information acquisition step for acquiring base station information including position information of each of a plurality of base stations that cover the communication area of ​​the route included in the acquired route information, a switching threshold acquisition step for acquiring a switching threshold of received radio wave strength that causes the wireless communication unit to switch to a base station that will be a new connection destination, and a switching threshold acquisition step for acquiring a switching threshold of received radio wave strength that causes the wireless communication unit to switch to a base station that will be a new connection destination based on at least the position information. The computer is caused to execute the following steps: a handover prediction area acquisition step for acquiring a handover prediction area in which a handover is predicted to occur, in which the wireless communication unit switches from a base station currently connected to to another base station, along the route being taken; an arrival time prediction step for predicting the arrival time at which the mobile body will arrive at the handover prediction area; a received radio wave strength prediction step for predicting the received radio wave strength of radio waves from the base station in the handover prediction area at the arrival time before arriving at the handover prediction area; and an output processing step for generating and outputting mobile communication support information based on a comparison result between the received radio wave strength predicted in the received radio wave strength prediction step and the switching threshold value.

[0021] (16) A communication method is applied to a communication system equipped with a wireless communication unit mounted on a mobile body and transmitting and receiving data to and from a base station via a wireless line, and includes a route information acquisition step for generating route information regarding a route along which the mobile body is scheduled to travel based on input information, a base station information acquisition step for acquiring base station information including position information of each of a plurality of base stations covering the communication area of ​​the route included in the acquired route information, a switching threshold acquisition step for acquiring a switching threshold of received radio wave strength that causes the wireless communication unit to switch to a base station that will be a new connection destination, and a switching threshold acquisition step for acquiring a switching threshold of received radio wave strength that causes the wireless communication unit to switch to a base station that will be a new connection destination based on at least the position information. the handover prediction area acquisition step of acquiring a handover prediction area in which a handover is predicted to occur, in which the base station to which the wireless communication unit is currently connected is switched to another base station, along a route included in the route; an arrival time prediction step of predicting an arrival time at which the mobile body will arrive at the handover prediction area; a received radio wave strength prediction step of predicting the received radio wave strength of radio waves from the base station in the handover prediction area at the arrival time before arriving at the handover prediction area; and an output processing step of generating and outputting mobile communication support information based on a comparison result between the received radio wave strength predicted in the received radio wave strength prediction step and the switching threshold value. [Effects of the Invention]

[0022] According to the present invention, the reliability of wireless communication can be ensured even when the communication environment changes. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a schematic diagram illustrating a communication system according to an embodiment of the present invention and an external communication device that performs wireless communication with the communication system. [Figure 2] 1 is a schematic diagram illustrating an example of a communication system according to an embodiment of the present invention and a road to which the communication system is applied. [Figure 3] 1 is a block diagram showing a hardware configuration of a communication device in a communication system according to an embodiment of the present invention. [Figure 4]1 is a block diagram showing a hardware configuration of an information processing device in a communication system according to an embodiment of the present invention. [Figure 5] FIG. 1 is a schematic diagram showing the communication state between a communication system and a base station when the communication environment in an HO area is good. [Figure 6] 1 is a schematic diagram showing the communication state between a communication system and a base station when the communication environment in an HO area deteriorates. [Figure 7] 1 is a block diagram showing a configuration of functional blocks of a communication device in a communication system according to an embodiment of the present invention. [Figure 8] 1 is a block diagram showing a functional block configuration of an information processing device in a communication system according to an embodiment of the present invention; [Figure 9] FIG. 10 is a schematic diagram showing an example of an avoidance route that avoids an HO prediction area. [Figure 10] FIG. 2 is a sequence diagram showing an example of a flow up to mobile communication support processing in a communication system according to an embodiment of the present invention. [Figure 11] 10 is a flowchart illustrating an example of a mobile communication assistance process executed by a communication processing device according to an embodiment of the present invention. [Figure 12] 10 is a flowchart showing an example of an HO area prediction process of the mobile communication assistance process executed by the communication processing device according to one embodiment of the present invention. [Figure 13] 10 is a flowchart showing an example of an HO support process among the mobile communication support processes executed by the communication processing device according to one embodiment of the present invention. [Figure 14] 14 is a flowchart showing an example of a process, different from that shown in FIG. 13, of the HO support process in the mobile communication support process executed by the communication processing device according to one embodiment of the present invention. [Figure 15] 15 is a flowchart showing an example of a process different from that shown in FIGS. 13 and 14 of the HO support process in the mobile communication support process executed by the communication processing device according to one embodiment of the present invention. [Figure 16]16 is a flowchart showing an example of a process, different from those shown in FIGS. 13 to 15, of the HO support process in the mobile communication support process executed by the communication processing device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, a communication system 100 will be described as an example of a communication system according to an embodiment of the present invention. Fig. 1 is a schematic diagram showing the communication system 100 and an external communication device 7 that performs wireless communication with the communication system 100. Fig. 2 is a schematic diagram showing an example of the communication system 100 and a road 83 to which the communication system 100 is applied.

[0025] The communication system 100 is a system that is mounted on a moving object 8 and that wirelessly communicates various data with an external communication device 7 in order to execute multiple functions of the moving object 8. Examples of the moving object 8 include a vehicle and a drone. The moving object 8 may be a moving object with a person on board, or may be a moving object without a person on board, such as an unmanned vehicle or an unmanned aerial vehicle. In this embodiment, the communication system 100 mounted on the moving object 8 that is a vehicle will be described as an example. Note that, among the moving objects 8 that are vehicles, the moving object 8 that is mounted with the communication system 100 is referred to as the host vehicle 81, and the moving object 8 that is another vehicle as seen from the host vehicle 81 is referred to as the other vehicle 82.

[0026] The host vehicle 81 is, for example, an autonomously controlled or remotely controlled automatically driving vehicle. The host vehicle 81 is configured to be able to wirelessly communicate with the external communication device 7. The host vehicle 81 may be, for example, a vehicle that performs automatic driving based on estimated position information of the host vehicle 81 and map information about the surroundings of the host vehicle 81. Furthermore, for example, the host vehicle 81 may be a vehicle that performs automatic driving based on a control signal from a remote control center or the like.

[0027] The various functions of the mobile object 8 may be, for example, functions related to autonomous driving, functions related to driving assistance other than autonomous driving, functions related to calls with the outside world, or functions related to entertainment such as videos and games. The functions related to autonomous driving may be, for example, a collision safety function for avoiding a collision with an obstacle or another vehicle 82, a function for autonomously controlling the host vehicle 81, or a function for remotely controlling the host vehicle 81. Data required for the function for autonomously controlling the host vehicle 81 may be, for example, route information along which the host vehicle 81 travels under autonomous control, vehicle surroundings information indicating the conditions around the host vehicle 81, and driving information such as the speed of the host vehicle 81. Data required for the function for remotely controlling the host vehicle 81 may be vehicle surroundings information or a control signal for controlling the driving of the host vehicle 81. In the following description, the functions of the mobile object 8 are referred to as vehicle functions.

[0028] Before describing the communication system 100, an external communication device 7 that performs wireless communication with the communication system 100 will be described.

[0029] Examples of the external communication device 7 include a base station 72, a control server 71, a satellite system 73, a drone 74, a communication device (not shown) of another vehicle 82, a roadside device (not shown), a communication terminal (not shown) carried by a pedestrian, etc. The communication system 100 performs V2X (vehicle-to-everything) communication with these devices, including V2I (vehicle-to-infrastructure) communication, V2V (vehicle-to-vehicle) communication, and V2N (vehicle-to-network) communication.

[0030] The base station 72 provides a V2N communication service by wirelessly communicating with various devices such as communication devices of mobile objects 8 moving on a road 83. The multiple base stations 72 are installed in different communication areas and are communicably connected to the control server 71 and other base stations 72 via a communication network NW. A communication area refers to a geographical range in which each base station 72 is responsible for communication with each mobile object 8. In the example shown in FIG. 2, base stations 72A and 72B, which are multiple base stations 72, are installed at intervals.

[0031] The base station 72 transmits data acquired through wireless communication with mobile objects 8 traveling within the communication area and various devices to the control server 71 via the communication network NW, or directly to the communication device of the mobile object 8.

[0032] Examples of communication networks NW include mobile communication networks operated by various communication carriers, core networks that connect mobile communication networks, and wide area networks (WANs) that include private networks and the Internet.

[0033] In this embodiment, the base station 72 holds, for example, its own identification information and data relating to the communication load (hereinafter referred to as communication load related data). The communication load related data includes, for example, communication traffic within its own communication area, the number of connections of communication partners such as mobile units 8 that are wirelessly communicating with the base station 72, and the like.

[0034] The control server 71 is communicably connected to external communication devices 7 such as a plurality of base stations 72 via a communication network NW, acquires various data from the external communication devices 7, and stores and manages the data in a database or the like.

[0035] The control server 71 also has a function of transmitting various data to the communication system 100 of the mobile object 8 via the base station 72, the communication devices of the other vehicles 82, etc. The information transmitted by the control server 71 includes, for example, map information of the route along which the mobile object 8 will travel, including roads 83, position information of the mobile object 8, control signals for remotely controlling the mobile object 8, and various data required for autonomous control of the mobile object 8, and the like, which are transmitted to the communication system 100. The map information includes position information of the base station 72, buildings, structures, etc. located near the route. The control server 71 also transmits current and past communication environment related information to the communication system 100. Examples of the communication environment related information include data on communication load such as communication traffic within the communication area A of the base station 72, the number of connections of communication partners such as mobile units 8 that are wirelessly communicating with the base station 72, images showing traffic conditions such as the traffic volume of mobile units 8, data such as images showing radio wave shields that exist around the base station 72 and block radio waves, and meteorological information including information on weather such as sunny, cloudy, rainy, etc., and amount of rain. Examples of radio wave shields include mobile units 8 such as buildings and vehicles.

[0036] The satellite system 73 may be, for example, a navigation satellite, a low-earth orbit satellite, or a geostationary orbit satellite that constitutes a global navigation satellite system (GNSS) such as a global positioning system (GPS) or a quasi-zenith satellite system. The satellite system 73, which is a navigation satellite, transmits GNSS signals indicating position information, satellite images that can grasp traffic information such as images including a road 83 on which the vehicle 81 is traveling, and the like to the ground. By analyzing the satellite images, it is possible to identify the position information of radio wave blocking objects such as buildings and mobile objects 8 that block radio waves. The satellite system 73, which is a low-earth orbit satellite, constitutes a non-terrestrial network (NTN) and enables wireless communication according to the 5G communication standard or the like.

[0037] The drone 74 transmits, for example, images including a road 83 on which the moving object 8 is traveling to the control server 71, the base station 72, the communication system 100, etc. The drone 74 constitutes a non-terrestrial network. For example, the satellite system 73 and the drone 74 may transfer data acquired from the control server 71, the base station 72, the communication device of the other vehicle 82, etc. to the communication system 100.

[0038] The communication device of the other vehicle 82 may perform V2V communication or V2N communication via a base station 72 with the communication devices of other moving bodies 8, including the vehicle itself 81, and may transmit data indicating the wireless communication status, such as the amount of communication with the outside world, as well as its own location information, identification information, etc.

[0039] The roadside units (not shown) are also called RSUs (road side units) or the like. Multiple roadside units are installed in different communication areas around (on the roadside of) a road 83. A communication area refers to the range in which each roadside unit is responsible for communication with each mobile object 8, and indicates, for example, a geographical range set along the road 83.

[0040] The roadside unit provides V2X communication services by wirelessly communicating with communication devices of mobile objects 8 traveling on the road 83 and various devices present in the vicinity. The roadside unit also transmits data acquired by wireless communication with mobile objects 8 traveling within the communication area and various devices to the control server 71 via the communication network NW, or directly to the communication devices of the mobile objects 8.

[0041] A communication terminal carried by a pedestrian or the like (hereinafter referred to as a pedestrian communication terminal) performs wireless communication with other external communication devices 7 including a base station 72. The pedestrian communication terminal may perform V2P communication with a communication device of a mobile object 8 including the vehicle 81, or may relay wireless communication between the communication device of the mobile object 8 and the base station 72.

[0042] 1, the communication system 100 is mounted on a mobile object 8 and includes a communication processing device 6, an in-vehicle sensor 4, and an outside-vehicle sensor 5. The communication system 100 predicts handover control of a base station 72 in response to a poor communication environment, and performs various controls such as warning of deterioration in communication quality due to handover, predicting function outages and reductions in function level, and adjusting function level. The communication system 100 according to this embodiment performs a mobile communication support process that predicts the HO area B, the arrival time at the HO area B, the communication environment in the HO area B at the arrival time, and the like, and outputs mobile communication support information based on the prediction results. This mobile communication support process ensures the reliability of communication even when the communication environment changes due to a handover or the like. The mobile communication support information is information for supporting the wireless communication of the moving object 8 while it is moving and the vehicle functions executed by that wireless communication.

[0043] The in-vehicle sensor 4 is a sensor for detecting driving information such as the speed, acceleration, and angular velocity of the host vehicle 81. Examples of the in-vehicle sensor 4 include a vehicle speed sensor that detects the speed of the host vehicle 81, an acceleration sensor that detects the acceleration of the host vehicle 81, and a yaw rate sensor that detects the yaw angular velocity of the host vehicle 81.

[0044] The exterior sensor 5 is a device for detecting information about the surroundings of the host vehicle 81. The exterior sensor 5 may be, for example, a radar such as a millimeter-wave radar, a LiDAR (light detection and ranging), or a camera. The camera detects information about the surroundings of the host vehicle 81 by capturing still or video images of the surroundings of the host vehicle 81. The millimeter-wave radar or LiDAR detects the distance, direction, relative speed, etc. of objects present around the host vehicle 81 based on transmission waves transmitted to the surroundings of the host vehicle 81 and reflected received waves. The exterior sensor 5 of this embodiment irradiates the surroundings with millimeter waves or laser light and detects surrounding objects as point cloud data, thereby detecting the positions, shapes, etc. of surrounding objects with high accuracy. The exterior sensor 5 transmits the detected point cloud data to the information processing device 1. Position information of radio wave blocking objects such as buildings and other vehicles 82 present around the host vehicle 81 can be obtained from the point cloud data detected by the exterior sensor 5.

[0045] The communication processing device 6 includes an input / output device (HMI; Human Machine Interface) 3, a communication device 2, and an information processing device 1. In this embodiment, the HMI 3, the communication device 2, and the information processing device 1 are separate entities, but they may also be integrated. By separating the communication device 2 from the information processing device 1, etc., the processing in the device can be specialized for wireless communication with the external communication device 7, allowing for smoother wireless communication.

[0046] The HMI 3 is an interface that receives information input by the driver of the vehicle 81 and outputs the information to the driver. The HMI 3 may be configured to include, for example, buttons, a display, a speaker, etc. The information that the driver inputs to the HMI 3 may be, for example, point information for generating route information along which the vehicle 81 is scheduled to travel. The point information may be the current location of the vehicle 81, the starting point of the planned route, the destination point, stop-off points along the route from the starting point to the destination point, and evacuation points. An evacuation point is, for example, an area where the vehicle 81, while autonomously driving, makes an emergency stop in the event of an abnormality, etc. Note that there may be multiple stop-off points and evacuation points.

[0047] The communication device 2 is a part that performs wireless communication with the external communication device 7. The communication device 2 may be a device that handles either or both of telematics and infotainment information. The communication device 2 of this embodiment transmits and receives data to and from the external communication device 7 via multiple wireless lines. The data acquired by the communication device 2 is transmitted to the information processing device 1.

[0048] Here, the hardware configuration of the communication device 2 will be described with reference to Fig. 3. Fig. 3 is a block diagram showing the hardware configuration of the communication device 2.

[0049] The communication device 2 includes a computer 28, a storage unit 23, a wireless communication unit 24, and an I / F unit 25. A bus 27 and the like connect these units together.

[0050] The computer 28 includes a processor 20 and a read-only memory (ROM) 21 and a random-access memory (RAM) 22 as main storage devices. The processor 20 may be a central processing unit (CPU), a microprocessing unit (MPU), a system on a chip (SoC), a digital signal processor (DSP), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a field-programmable gate array (FPGA). Alternatively, the processor 20 may be a combination of these. The processor 20 may also be a combination of these with a hardware accelerator or the like. The processor 20 controls each component to realize various functions of the communication device 2 based on programs such as firmware, system software, and application software stored in the ROM 21, the RAM 22, or an auxiliary storage device that is part of the storage unit 23. Note that some or all of the programs may be incorporated into the circuitry of the processor 20.

[0051] The storage unit 23 is a storage area for various programs and various data for causing the hardware group to function as the communication device 2, and can be configured with a ROM, RAM, flash memory, a solid-state drive (SSD), a hard disk drive (HDD), etc. Specifically, the storage unit 23 stores programs and the like for causing the computer 28 to execute each function of this embodiment.

[0052] The wireless communication unit 24 executes processing for the communication device 2 to perform wireless communication with the external communication device 7. The wireless communication unit 24 can transmit data using multiple wireless lines. The type of wireless line is not particularly limited. Examples of wireless lines include wireless LAN (Local Area Network) communication standards including Wi-Fi (registered trademark), LTE (Long Term Evolution) communication standards, wireless communication lines within the same communication carrier based on the 5G communication standard, and wireless communication lines between different communication carriers. Wireless communication lines based on communication standards that are being put into practical use, such as the 6G communication standard, can also be used.

[0053] The I / F unit 25 is a communication interface for the communication device 2 to communicate with the information processing device 1. The I / F unit 25 may be a wired communication interface compatible with an in-vehicle communication means such as a wire harness for electrical communication or an optical fiber cable for high-speed optical communication, or at least a part of the I / F unit 25 may be a wireless communication interface.

[0054] The GNSS unit 26 includes an antenna and receives GNSS signals, etc. The GNSS unit 26 transmits the received GNSS signals to the processor 20. The GNSS unit 26 may transmit the received GNSS signals to the information processing device 1 via the I / F unit 25.

[0055] The following describes the information processing device 1. The information processing device 1 acquires and processes various information from an in-vehicle sensor 4, an out-vehicle sensor 5, a communication device 2, and an HMI 3. The information processing device 1 controls the communication device 2 and functions of the vehicle 81 related to autonomous driving and the like through wireless communication with an external communication device 7.

[0056] Next, an example of the hardware configuration of the information processing device 1 will be described with reference to Fig. 4. Fig. 4 is a block diagram showing the hardware configuration of the information processing device 1.

[0057] The information processing device 1 includes a computer 16, a storage unit 13, and an I / F unit 14. A bus 15 and the like connect these units together.

[0058] The computer 16 includes a processor 10 and a read-only memory (ROM) 11 and a random-access memory (RAM) 12 as main storage devices. The processor 10 may be a central processing unit (CPU), a microprocessing unit (MPU), a system on a chip (SoC), a digital signal processor (DSP), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a field-programmable gate array (FPGA). Alternatively, the processor 10 may be a combination of these. The processor 10 may also be a combination of these with a hardware accelerator or the like. The processor 10 controls each unit to realize various functions of the information processing device 1 based on programs such as firmware, system software, and application software stored in the ROM 11, the RAM 12, or an auxiliary storage device that is part of the storage unit 13. Note that some or all of the programs may be incorporated into the circuitry of the processor 10.

[0059] The storage unit 13 is a storage area for storing various programs and various data for causing the hardware group to function as the information processing device 1, and can be configured with a ROM, RAM, flash memory, a solid-state drive (SSD), a hard disk drive (HDD), or the like. Specifically, the storage unit 13 stores programs for causing the computer 16 to execute each function of this embodiment, and information related to vehicle functions (hereinafter referred to as vehicle function-related information). Examples of the vehicle function-related information include the details of vehicle functions such as collision safety functions, and the details of data transmitted and received via wireless communication.

[0060] The I / F unit 14 is a wired communication interface through which the information processing device 1 communicates with the communication device 2, the in-vehicle sensor 4, the outside sensor 5, or the ECU 84 of the host vehicle 81. The information processing device 1 uses the I / F unit 14 to communicate with the in-vehicle sensor 4, the outside sensor 5, the ECU 84, etc. via an in-vehicle LAN including, for example, Ethernet (registered trademark), which is implemented by CAN (Controller Area Network) communication, LIN (Local Interconnect Network) communication, electrical communication, or optical communication. Note that the I / F unit 14 may be a wired communication interface compatible with in-vehicle communication means, such as a wire harness for electrical communication or an optical fiber cable for high-speed optical communication, or at least a part of the I / F unit 14 may be a wireless communication interface.

[0061] 2, for example, when the vehicle 81 continues traveling within a communication area A covered by a base station 72A and the strength of the radio wave received by the communication device 2 from the base station 72A drops below a switching threshold R0, a handover must be performed to continue wireless communication, and the communication destination must be switched from the base station 72A to, for example, a base station 72B. The handover is performed, for example, in a handover area (hereinafter referred to as an HO area) B, which is an area where the communication areas A of the base stations 72 overlap. The switching threshold R0 is a reference value of the strength of the radio wave received that causes the communication device 2 to perform a handover.

[0062] For example, if handover by a mobile unit 8, which is an autonomous vehicle, does not proceed smoothly due to a deterioration in the communication environment, etc., data loss or delays in data transmission speed may occur, making it impossible to perform important functions such as autonomous driving, and there is a risk that the reliability of the mobile unit 8's functions via wireless communication cannot be guaranteed.

[0063] The traffic conditions, such as the traffic volume of the mobile object 8, on the road 83 on which the mobile object 8 travels change depending on the location, time of day, and events such as the occurrence of an accident. In addition, the environment around the road 83 also changes as the mobile object 8 moves, such as a rural area with few radio wave shields or an urban area with many radio wave shields. Therefore, the communication environment around the communication device 2 mounted on the mobile object 8 also tends to change depending on the traffic conditions, etc.

[0064] Fig. 5 is a schematic diagram showing a situation where the communication environment in HO area B is good. Fig. 6 is a schematic diagram showing a situation of road 83 where the communication environment in HO area B is deteriorated.

[0065] In the example shown in Fig. 5, there is little traffic of mobile objects 8 around the base station 72A where the vehicle 81 is traveling, and there is little communication traffic from the mobile objects 8 and other external communication devices 7. There are also few radio wave obstructions between the base station 72 and the vehicle 81. In this situation, as shown in Fig. 5, the vehicle 81 can continue traveling without performing a handover. This allows the communication device of the mobile object 8 to communicate wirelessly with the base station 72 without interruption.

[0066] On the other hand, in the example shown in FIG. 6 , there is heavy traffic in HO area B, and many radio wave obstructions, such as other vehicles 82, exist between the host vehicle 81 and HO area B or base station 72. In such a situation, as shown in FIG. 6 , the communication environment in HO area B deteriorates, and the received radio wave strength from base station 72B in HO area B decreases. In this case, a handover is performed early to switch the connection from base station 72A to base station 72B or the like. The handover may cause interruptions or delays in communication between the communication device 2 and the control server 71 or the like via the base station 72. For this reason, for example, when a mobile object 8, which is an autonomous vehicle, moves through HO area B, data loss or delays in data transmission speed may occur in wireless communication with base station 72, which may prevent the mobile object 8 from performing important functions, such as autonomous driving, and may make it difficult to ensure the reliability of the mobile object 8's functions via wireless communication.

[0067] The communication system 100 according to this embodiment performs a mobile communication support process that predicts the HO area B, the arrival time at the HO area B, the communication environment in the HO area B at the arrival time, and the like, and outputs mobile communication support information based on the prediction results. This mobile communication support process ensures the reliability of communication even when the communication environment changes due to a handover or the like. The mobile communication support information is information for supporting the wireless communication of the moving object 8 while it is moving and the vehicle functions executed by that wireless communication.

[0068] Next, various functions that are realized by the processor 20 of the communication device 2 and that execute the mobile communication support process will be described with reference to FIG.

[0069] As shown in FIG. 7, the processor 20 of the communication device 2 includes a self-position estimation unit 201 and a communication control unit 202.

[0070] The self-position estimation unit 201 executes a process of estimating position information (hereinafter referred to as self-position information) of the vehicle 81. The self-position estimation unit 201 may estimate the self-position information based on, for example, map information, a GNSS signal, or the like received from the control server 71.

[0071] The communication control unit 202 executes processing to control wireless communication between the communication device 2 and the external communication device 7 and communication between the communication device 2 and the information processing device 1. The communication control unit 202 controls wireless communication with the external communication device 7 by the wireless communication unit 24.

[0072] Next, various functions realized by the processor 10 of the information processing device 1 will be described with reference to FIG.

[0073] As shown in FIG. 8, the processor 10 of the information processing device 1 includes a location information acquisition unit 101, a map information acquisition unit 102, a position information acquisition unit 103, a route information acquisition unit 104, a base station information acquisition unit 105, a communication environment related information acquisition unit 106, a threshold acquisition unit 107, an HO prediction area acquisition unit 108, an arrival time prediction unit 109, a received radio wave intensity prediction unit 110, a function adjustment unit 111, and an output processing unit 112.

[0074] The point information acquisition unit 101 executes a process of acquiring point information. For example, the point information acquisition unit 101 executes a process of acquiring point information input by the driver from the HMI 3. The point information acquired from the HMI 3 may be position information such as a departure point of a planned route of the vehicle 81, a destination point, a stop-off point on the route from the departure point to the destination point, an evacuation point, etc. The point information acquisition unit 101 may also acquire self-position information of the current location acquired by the position information acquisition unit 103 as point information.

[0075] The map information acquisition unit 102 executes a process of acquiring map information including at least the road 83 on which the vehicle 81 is traveling and the road 83 on which the vehicle 81 is scheduled to travel. The map information acquisition unit 102 acquires the map information from the control server 71 via the communication device 2, for example.

[0076] The position information acquisition unit 103 executes a process of acquiring self-position information of the current location (hereinafter referred to as current location information). The position information acquisition unit 103 may acquire, for example, current location information of the vehicle 81 estimated by the self-position estimation unit 201 of the communication device 2. Alternatively, for example, the position information acquisition unit 103 may estimate current location information of the vehicle 81 based on map information, a GNSS signal, etc. acquired by the map information acquisition unit 102, and acquire the estimated information as the current location information. Alternatively, for example, the position information acquisition unit 103 may acquire vehicle surroundings information such as point cloud information around the vehicle 81 from the external vehicle sensor 5, acquire map information from the control server 71 via the communication device 2, and compare the vehicle surroundings information with the map information to estimate the position information of the vehicle 81, thereby acquiring the self-position information.

[0077] The route information acquisition unit 104 executes a process of acquiring planned route information regarding a route along which the vehicle 81 is scheduled to travel. The route information acquisition unit 104 may generate route information based on the point information acquired by the point information acquisition unit 101, the map information acquired by the map information acquisition unit 102, the current location information acquired by the position information acquisition unit 103, and the like, and acquire the generated information as planned route information. As a method of generating the planned route information, for example, a starting point or the current location, a destination point, a stop-off point, and an evacuation point may be identified on a map indicated by the map information, and roads 83 connecting these may be generated as planned route information. Furthermore, for example, the route information acquisition unit 104 may acquire route information as planned route information from a car navigation device or the like that generates route information, or may acquire route information stored in the control server 71 from the control server 71 as planned route information.

[0078] The base station information acquisition unit 105 executes a process of acquiring base station information including the location information and identification information of each of the plurality of base stations 72 that exist on the route included in the planned route information and in the vicinity thereof.

[0079] The communication environment related information acquisition unit 106 executes a process of acquiring, via the communication device 2, communication environment related information about the road 83 and its surroundings, which is included in the planned route information acquired by the route information acquisition unit 104. The communication environment related information acquisition unit 106 may acquire, for example, data related to communication loads, such as communication traffic in a communication area A covered by base stations 72 installed at each point on the road 83 included in the planned route information managed by the control server 71, and the number of connections to the base station 72 from communication devices of mobile objects 8 and communication terminals of pedestrians and the like that wirelessly communicate with the base station 72 (hereinafter, communication load related data). Furthermore, for example, the communication environment related information acquisition unit 106 may acquire communication load related data, such as current communication traffic in the communication area A of the base station 72, or communication load related data, such as communication traffic in the same time period in the past. For example, the communication environment related information acquisition unit 106 may acquire position information and wireless communication volume of each mobile body 8 from a communication device of another vehicle 82 traveling on a road 83 included in the planned route information by V2V communication with the other vehicle 82 or V2N2V communication via the base station 72 or the communication network NW. For example, the communication environment related information acquisition unit 106 may acquire an image including the road 83 indicated in the planned route information from the satellite system 73 or the drone 74, and extract information about traffic conditions such as traffic volume of the mobile body 8, position information of the mobile body 8 and radio wave shielding objects such as buildings, from the acquired image. For example, weather information may be acquired from the satellite system 73, which is a meteorological satellite. For example, the communication environment related information acquisition unit 106 may acquire communication volume between the pedestrian communication terminal of a pedestrian walking on the road 83 included in the planned route information and the base station 72, etc., from the base station 72, the pedestrian communication terminal, etc.

[0080] The threshold acquisition unit 107 executes a process of acquiring a switching threshold R0 for received radio wave strength set in each base station 72. In the communication system 100 according to this embodiment, when the received radio wave strength received from the currently connected base station 72 falls below the switching threshold R0, the base station 72 searches for a new base station 72 to be connected to the communication device 2 in wireless communication, and switches the connection to the new base station 72.

[0081] The HO predicted area acquisition unit 108 executes a process to acquire a predicted area of ​​HO area B where handover will be performed (hereinafter referred to as HO predicted area). The HO predicted area acquisition unit 108 may acquire, for example, predetermined location information of HO area B stored in the control server 71 or each base station 72 as the HO predicted area. The HO predicted area acquisition unit 108 may also acquire the HO predicted area by predicting HO area B based on various information. In this case, the HO predicted area acquisition unit 108 may predict HO area B based on base station information, or may predict HO area B based on the base station information and the switching threshold R0 of each base station 72 indicated by the base station information, or may further take communication environment-related information into account when predicting HO area B.

[0082] When the HO area B is acquired by the HO prediction area acquisition unit 108, the arrival time prediction unit 109 predicts the scheduled arrival time, which is the time when the host vehicle 81 will arrive in the HO area B. The arrival time prediction unit 109 may, for example, acquire driving information such as the vehicle speed of the host vehicle 81 from the in-vehicle sensor 4 and predict the scheduled arrival time based on the driving information. The arrival time prediction unit 109 may predict the scheduled arrival time using at least one of the legal speed limit of the road 83 indicated by the scheduled route information, the average speed of the traveling host vehicle 81, traffic conditions, and the vehicle speed of the host vehicle 81.

[0083] The received signal strength prediction unit 110 executes a process of predicting the received signal strength from the base station 72 in the HO prediction area at the scheduled arrival time predicted by the arrival time prediction unit 109 before the host vehicle arrives at the HO prediction area. In the following description, the predicted value of the received signal strength from the base station 72 in the HO prediction area at the scheduled arrival time is referred to as predicted value R1. The predicted value R1 may be a predicted value for radio waves transmitted from the currently connected base station 72, or may be a predicted value for radio waves transmitted from both the currently connected base station 72 and a base station 72 (candidate base station) that is a candidate for a new connection destination for wireless communication with the communication device 2.

[0084] The received signal strength prediction unit 110 may use, for example, the past received signal strength from the base station 72 in the HO prediction area during the same time period as the scheduled arrival time as the predicted value R1. Alternatively, for example, the received signal strength prediction unit 110 may predict the predicted value R1 based on at least one of the following information: the total wireless communication volume of communication devices, such as other vehicles 82, currently traveling in the HO prediction area; data related to the current communication load of the base station 72 in the HO prediction area; and information on radio wave obstructions located between the vehicle 81 and the base station 72 that is a candidate base station identified by the position information of the base station 72 and the HO prediction area. Alternatively, for example, the received signal strength prediction unit 110 may predict the predicted value R1 based on both past communication environment-related information in the HO prediction area and current communication environment-related information obtained in real time. Alternatively, for example, the received signal strength prediction unit 110 may predict the predicted value R1 by taking into account weather information for the HO prediction area at the predicted arrival time. As a result, the higher the frequency of radio waves used in wireless communication, the greater the tendency for the radio waves to be affected by rain and the like. Therefore, the predicted value R1 can be more accurately predicted for handovers in wireless communication using high-frequency radio waves.

[0085] When the predicted value R1 is equal to or less than the switching threshold R0, the function adjustment unit 111 executes processing to limit (hereinafter referred to as function limitation) or stop (hereinafter referred to as function stop) the vehicle functions to be executed by transmitting and receiving data to and receiving data from the external communication device 7 or the like via the wireless communication unit 24 as necessary. Function limitation means not executing part of a vehicle function or changing to an alternative function that requires less processing. For example, if the vehicle function is a level 5 autonomous driving function, the function limitation may be, for example, lowering the autonomous driving level from level 5 to level 4 (in this case, the autonomous driving level limited to level 4 is referred to as a restricted level). Specifically, the function adjustment unit 111 outputs a control signal to the ECU 84 to change the autonomous driving level of the host vehicle 81. Note that the autonomous driving level may be defined, for example, by the Society of Automotive Engineers (SEA).

[0086] The function adjustment unit 111 restricts or suspends functions, for example, when the vehicle 81 is within a predetermined distance from the HO prediction area (hereinafter referred to as the HO prediction area or its vicinity). The predetermined distance may be set according to, for example, the communication area A of the base station 72, the speed of the vehicle 81, the vehicle functions to be subject to the function restriction, etc. The predetermined distance may be set, for example, to 30 m if the speed of the vehicle 81 is within the legal speed limit, or 120 m if the speed is higher.

[0087] The function adjustment unit 111 determines whether it is possible to transmit and receive the amount of data required to execute a vehicle function in the HO prediction area based on the predicted value R1. In this specification, the term "data amount" refers to the amount of data per unit time, i.e., the data transfer rate. If the function adjustment unit 111 determines that it is possible to transmit and receive the amount of data required to execute a vehicle function in the HO prediction area, it does not restrict or suspend the function of the vehicle function. On the other hand, if it determines that it is impossible to transmit and receive the amount of data required to execute a vehicle function in the HO prediction area, it restricts or suspends the function according to the amount of data that is insufficient.

[0088] The output processing unit 112 generates and outputs various types of mobile communication support information based on the comparison result between the predicted value R1 and the switching threshold R0 before the host vehicle 81 reaches the HO prediction area. Specifically, when the predicted value R1 is equal to or less than the switching threshold R0, the output processing unit 112 generates the mobile communication support information and outputs the mobile communication support information to the HMI 3. The mobile communication support information may be, for example, information predicting a deterioration in communication quality between the wireless communication unit 24 and the base station 72. Furthermore, for example, the mobile communication support information may be information predicting a function restriction or function stop of a vehicle function by the function adjustment unit 111, or selection information for allowing the driver of the host vehicle 81 to select whether to continue or stop the vehicle function that is to be restricted. Furthermore, for example, the mobile communication support information may be information predicting a change in the autonomous driving level when the autonomous driving level is changed by the function adjustment unit 111. For example, the mobile communication support information may be information to prompt the driver to switch the control mode of the vehicle 81 from automatic control to manual control when the vehicle function whose function is restricted by the function adjustment unit 111 is a collision safety function related to automatic driving.

[0089] 9 is a schematic diagram showing an example of an avoidance route 92 that avoids the HO prediction area. For example, when the prediction value R1 is equal to or less than the switching threshold R0, the output processing unit 112 may generate and output the avoidance route 92 that avoids the HO prediction area as mobile communication support information.

[0090] 9 shows a situation in which traffic volume is heavy in HO area B, deteriorating the communication environment in HO area B. In such a situation, if the vehicle 81 travels as planned along the initial route 91 first acquired by the route information acquisition unit 104, a handover may cause interruption or delay in data transmission, which may hinder the execution of important vehicle functions of the vehicle 81.

[0091] 9, the communication environment on the route approaching base station 72A is good, and HO area B can also be avoided, maintaining good communication quality. When the predicted value R1 is equal to or less than the switching threshold R0, the output processing unit 112 generates an avoidance route 92 before reaching the HO predicted area, and outputs information to the HMI 3 to prompt the driver to change route from the initial route 91 to the avoidance route 92. This ensures the reliability of wireless communication.

[0092] The output processing unit 112 may, for example, acquire surrounding environment information of the HO prediction area at the scheduled arrival time and generate the avoidance route 92 based on the surrounding environment information. Examples of the surrounding environment information include base station information of multiple base stations 72 present around the HO prediction area, branch routes from the initial route 91, and position information of radio wave obstructions such as mobile objects 8 and buildings. The surrounding environment information may be acquired from, for example, map information, images, point cloud data detected by the external sensor 5, and the like. Furthermore, for example, the output processing unit 112 may generate the avoidance route by taking into account at least one of travel information of the host vehicle 81 detected by the in-vehicle sensor 4 and information indicating the surrounding conditions of the host vehicle 81 detected by the external sensor 5. Examples of the travel information of the host vehicle 81 detected by the in-vehicle sensor 4 include vehicle speed. Examples of the information indicating the surrounding conditions of the host vehicle 81 detected by the external sensor 5 include metal obstructions that may be targets for the host vehicle 81 to avoid and the surrounding environment of a preceding vehicle. Based on this information, the output processing unit 112 may generate an avoidance route 92 with a good communication environment or a route that will not cause a collision accident due to deterioration of vehicle functions.

[0093] Next, an example of the processing flow by the communication processing device 6 in the communication system 100 from generating planned route information for the vehicle 81 to outputting the avoidance route 92 will be described with reference to Fig. 10. Fig. 10 is a sequence diagram showing an example of the processing flow from inputting location information by the driver to outputting the avoidance route 92.

[0094] As shown in FIG. 10, in step S101, the HMI 3 receives location information such as a departure point and a destination input by the driver of the vehicle 81, for example.

[0095] In step S102, the HMI 3 transmits the location information received in step S101 to the information processing device 1.

[0096] In step S103 , the communication device 2 transmits the map information received from the control server 71 to the information processing device 1 .

[0097] In step S104, the information processing device 1 generates planned route information based on the vehicle surroundings information of the vehicle 81 transmitted from the external sensor 5, the location information transmitted from the HMI 3 in step S102, and the map information transmitted from the communication device 2 in step S103.

[0098] In step S105, the communication device 2 transmits the base station information acquired from the control server 71 to the information processing device 1. The base station information transmitted from the communication device 2 in step S105 includes identification information and location information of the road 83 included in the planned route information and each of the multiple base stations 72 arranged in the vicinity thereof.

[0099] In step S106, the communication device 2 transmits the switching threshold value R0 of each base station 72 acquired from the control server 71 or the base station 72 to the information processing device 1.

[0100] In step S107, the information processing device 1 predicts an HO area B based on the base station information received in step S105, and transmits the predicted HO predicted area to the communication device 2.

[0101] In step S108, the information processing device 1 predicts the scheduled arrival time at which the vehicle 81 will arrive at the HO prediction area based on driving information of the vehicle 81 transmitted from the in-vehicle sensor 4, and transmits the predicted scheduled arrival time to the communication device 2.

[0102] In step S109, the information processing device 1 predicts the received radio wave strength of radio waves from the connected base station 72 in the HO prediction area at the scheduled arrival time predicted in step S108, just before the HO prediction area, and obtains the predicted value R1.

[0103] In step S110, the information processing device 1 compares the switching threshold value R0 transmitted from the communication device 2 in step S106 with the predicted value R1 predicted in step S109, and determines, based on the comparison result, whether to generate the avoidance route 92. Specifically, the information processing device 1 generates the avoidance route 92 when the predicted value R1 is equal to or less than the switching threshold value R0.

[0104] In step S111, the information processing device 1 transmits forecast information (advance notice information) for the generation of the avoidance path 92 to the HMI 3.

[0105] In step S112, the HMI 3 outputs the forecast information (advance notice information) for the generation of the avoidance path 92 acquired from the information processing device 1 to a display, a speaker, or the like.

[0106] In step S113, the communication device 2 transmits the map information and the like received from the control server 71 to the information processing device 1.

[0107] In step S114, the information processing device 1 generates an avoidance route 92 based on the map information acquired from the communication device 2, the driving information acquired from the in-vehicle sensor 4, and the like.

[0108] In step S115, the information processing device 1 transmits the generated avoidance path 92 to the HMI 3.

[0109] In step S116, the HMI 3 outputs the avoidance route 92 transmitted from the information processing device 1 in step S114 to a display or the like.

[0110] Next, an example of the mobile communication assistance process executed by the communication processing device 6 will be described with reference to FIGS.

[0111] First, the overall flow of the mobile communication assistance process will be described with reference to Fig. 11. Fig. 11 is a flowchart showing an example of the mobile communication assistance process executed by the communication processing device 6.

[0112] As shown in FIG. 11, in step S10, the processor 10 of the information processing device 1 executes the HO prediction process.

[0113] In step S21, the processor 10 or 20 of the communication processing device 6 determines whether the host vehicle 81 has approached the HO prediction area acquired by the HO prediction process to a predetermined distance. If the processor 10 or 20 determines that the host vehicle 81 has approached to the predetermined distance (step S21; YES), the processor 10 or 20 proceeds to step S30. On the other hand, if the processor 10 or 20 determines that the host vehicle 81 has not approached to the predetermined distance (step S21; NO), the processor 10 or 20 repeats the process of step S21 after a predetermined time has elapsed.

[0114] In step S30, the processor 10 and the processor 20 execute the assistance information output process, and then the processor 10 and the processor 20 end the mobile communication assistance process.

[0115] Next, the HO prediction process in step S10 of the mobile communication assistance process will be described with reference to Fig. 12. Fig. 12 is a flowchart showing an example of the HO prediction process executed by the communications processing device 6.

[0116] As shown in FIG. 12, in step S11, the location information acquisition unit 101 of the processor 10 acquires location information such as the departure point and destination point of the vehicle 81 input by the driver of the vehicle 81 via the HMI 3 from the HMI 3.

[0117] In step S12, the map information acquisition unit 102 acquires map information transmitted from the control server 71 via the communication device 2, and the position information acquisition unit 103 acquires current position information of the vehicle 81 as its own position information.

[0118] In step S13, the route information acquisition unit 104 generates planned route information based on the location information, self-position information, and map information acquired in steps S11 and S12.

[0119] In step S14, the base station information acquisition unit 105 acquires base station information of the base station 72 that covers the communication area A of the route included in the planned route information generated in step S13.

[0120] In step S15, the threshold acquisition unit 107 acquires a switching threshold R0 for the received radio wave strength of at least the currently connected base station 72, and stores the acquired threshold in the storage unit 13. The threshold acquisition unit 107 may acquire the switching threshold R0 of not only the currently connected base station 72, but also the base station 72 indicated by the base station information acquired in step S13.

[0121] In step S16, the HO predicted area acquisition unit 108 predicts the HO area B based on the base station information and the like acquired in step S14, and acquires the HO predicted area.

[0122] In step S17, the arrival time prediction unit 109 acquires the travel information including the vehicle speed of the host vehicle 81 from the in-vehicle sensor 4.

[0123] In step S18, the arrival time prediction unit 109 predicts the estimated arrival time at which the host vehicle 81 will arrive at the HO prediction area based on the vehicle speed acquired in step S17, the map information acquired in step S12, etc. Then, the processors 10 and 20 terminate the HO prediction process.

[0124] Next, the assistance information output process in step S30 of the mobile communication assistance process will be described with reference to Fig. 13. Fig. 13 is a flowchart showing an example of the assistance information output process executed by the communication processing device 6.

[0125] 13, in step S31, the communication environment related information acquisition unit 106 acquires communication environment related information for the HO prediction area or its vicinity acquired in step S16. For example, the communication environment related information acquisition unit 106 may acquire, as the communication environment related information, communication traffic between base stations 72, including the currently connected base station 72, and other vehicles 82 or other external communication devices, position information and number of radio wave obstructions, such as moving objects 8 and buildings, existing between the base station 72 and the host vehicle 81, and weather information.

[0126] In step S32, the received radio wave strength prediction unit 110 predicts the received radio wave strength from the base station 72 in the HO prediction area at the scheduled arrival time predicted in step S18 based on the communication environment related information acquired in step S31, and obtains a predicted value R1.

[0127] In step S33, the received radio wave intensity predicting unit 110 reads out from the storage unit 13 the switching threshold value R0 acquired in step S15.

[0128] In step S34, the output processing unit 112 compares the switching threshold value read in step S33 with the predicted value R1 predicted in step S32. If the output processing unit 112 determines that the predicted value R1 is equal to or less than the switching threshold value R0 (step S34; YES), the output processing unit 112 outputs mobile communication assistance information that forecasts deterioration of communication quality between the wireless communication unit 24 and the base station 72 to the HMI 3 (step S35). Then, the HMI 3 outputs the mobile communication assistance information acquired from the information processing device 1 to, for example, a display. On the other hand, if the output processing unit 112 determines that the predicted value R1 exceeds the switching threshold value R0 (step S34; NO), the output processing unit 112 outputs information to the HMI 3 to prompt the driver of the host vehicle 81 to continue traveling on the initial route 91 (step S36). Then, the HMI 3 may display a message urging the driver to continue traveling on, for example, a display that displays the planned route information. If the output processing unit 112 determines that the predicted value R1 exceeds the switching threshold value R0 (step S34; NO), the output processing unit 112 may end the support information output process without performing the process of step S36.

[0129] Next, an example of a processing flow of the support information output processing that is different from the example shown in Fig. 13 will be described with reference to Fig. 14. Note that the processing of steps S31 to S33 and S36 shown in Fig. 14 is the same as the processing in the example shown in Fig. 13, and therefore description thereof will be omitted.

[0130] As shown in FIG. 14, in step S34, if the output processing unit 112 determines that the predicted value R1 is equal to the switching threshold value R0 (step S34; YES), the process proceeds to step S37.

[0131] In step S37, the output processing unit 112 acquires surrounding environment information for the HO prediction area at the scheduled arrival time predicted in step S18. For example, the surrounding environment information may include map information including a route that exists around the HO prediction area, branches off from the initial route 91 so as to avoid the HO prediction area, and is capable of reaching the destination acquired in step S11, as well as base station information for the base stations 72 that exist around the route included in the map information. Furthermore, for example, the surrounding environment information may include an image of the surroundings of the HO prediction area acquired from the satellite system 73 or the like, and information indicating the situation around the host vehicle 81 detected by the external sensor 5.

[0132] In step S38, the output processing unit 112 outputs information predicting the generation of the avoidance path 92 to the HMI 3. For example, since a deterioration in communication quality is predicted, the HMI 3 displays on the display a message indicating that the avoidance path 92 for avoiding the deterioration in communication quality is scheduled to be generated or is currently being generated.

[0133] In step S39, the output processing unit 112 generates the avoidance route 92 based on the surrounding environment information acquired in step S37. At this time, the output processing unit 112 may acquire the avoidance route 92 by taking into account the traveling information of the host vehicle 81 from the in-vehicle sensor 4.

[0134] In step S40, the output processing unit 112 outputs information indicating the avoidance route 92 generated in step S39 to the HMI 3. Then, the HMI 3 displays the obtained avoidance route 92 on a display or the like, and outputs an image or sound as a message urging the driver to travel along the avoidance route 92, for example.

[0135] Next, an example of a processing flow of the support information output processing that is different from the examples shown in Fig. 13 and Fig. 14 will be described with reference to Fig. 15. Note that the processing of steps S31 to S33, S36, and S37 to S40 shown in Fig. 15 is the same as the processing in the example shown in Fig. 14, and therefore description thereof will be omitted.

[0136] As shown in FIG. 15, in step S34, if the output processing unit 112 determines that the predicted value R1 is equal to the switching threshold value R0 (step S34; YES), the process proceeds to step S341.

[0137] In step S341, the function adjustment unit 111 determines whether to stop or limit the function of a vehicle function executed by transmitting and receiving data between the wireless communication unit 24 and the base station 72. For example, the function adjustment unit 111 determines whether to stop or limit the function based on the predicted value R1 predicted in step S32 and the amount of data required to execute the vehicle function. If the function adjustment unit 111 determines to stop the function (step S341; YES), the process proceeds to step S37, where the avoidance route 92 is generated and output. On the other hand, if the function adjustment unit 111 determines to limit the function (step S341; NO), the process proceeds to step S41.

[0138] In step S41, the output processing unit 112 outputs information predicting the functional restriction of the vehicle function by the function adjustment unit 111 to the HMI 3. The HMI 3 outputs a message indicating that the functional restriction of the vehicle function is to be implemented, for example, because a deterioration in communication quality is predicted, as an image on the display or as an audio message to the speaker.

[0139] In step S42, the output processing unit 112 outputs selection information to the HMI 3 to allow the driver of the vehicle 81 to select whether to continue or stop the vehicle function to be restricted. The HMI 3 outputs the selection information, for example, as an image on the display or as sound to the speaker.

[0140] Next, an example of a processing flow of the support information output processing that is different from the example shown in Figures 13 to 15 will be described with reference to Figure 16. Note that the processing of steps S31 to S33, S36, S37 to S40, S41, and S42 shown in Figure 16 is the same as the processing in the example shown in Figure 15, and therefore description thereof will be omitted.

[0141] As shown in FIG. 16, in step S34, if the output processing unit 112 determines that the predicted value R1 is equal to or less than the switching threshold value R0 (step S34; YES), the process proceeds to step S341.

[0142] In step S341, the function adjustment unit 111 determines whether to stop or control the vehicle function executed by transmitting and receiving data between the wireless communication unit 24 and the base station 72. If the function adjustment unit 111 determines to stop the function (step S341; YES), the process proceeds to step S37, where the avoidance route 92 is generated and output. On the other hand, if the function adjustment unit 111 determines to control the function (step S341; NO), the process proceeds to step S342.

[0143] In step S342, function adjustment unit 111 determines whether the vehicle function determined in step S341 to be subjected to function control is a function related to autonomous driving. If function adjustment unit 111 determines that the vehicle function is an autonomous driving function (step S342; YES), it proceeds to step S343. On the other hand, if function adjustment unit 111 determines that the vehicle function is not an autonomous driving function (step S342; NO), output processing unit 112 executes the processes of steps S41 and S42, and then terminates the assistance information output process.

[0144] In step S343, the function adjustment unit 111 determines whether the vehicle function determined in step S342 to be related to autonomous driving is a collision safety function. If the function adjustment unit 111 determines that the vehicle function is not a collision safety function (step S343; NO), the function adjustment unit 111 proceeds to step S43. In step S43, the output processing unit 112 outputs information predicting a change in the autonomous driving level to the HMI 3. In step S44, the function adjustment unit 111 adjusts the autonomous driving level to the level predicted in step S44. On the other hand, if the function adjustment unit 111 determines that the vehicle function is a collision safety function (step S343; YES), the function adjustment unit 111 proceeds to step S45.

[0145] In step S45, the output processing unit 112 outputs to the HMI 3 information predicting a change in the autonomous driving level.

[0146] In step S46, the output processing unit 112 outputs information prompting the driver of the vehicle 81 to switch from automatic control to manual control to the HMI 3. Then, the HMI 3 outputs, for example, a message prompting the driver of the vehicle 81 to switch to manual control as an image on the display or as an audio message to the speaker.

[0147] According to the embodiment described above, the following effects are achieved.

[0148] The communication system 100 according to this embodiment is a communication system 100 that is mounted on a vehicle 81 and includes a wireless communication unit 24 that transmits and receives data to and from a base station 72 via a wireless line, and includes a route information acquisition unit 104 that generates planned route information regarding a route along which the vehicle 81 is scheduled to travel based on input information, a base station information acquisition unit 105 that acquires base station information including location information of each of a plurality of base stations 72 that cover the communication area of ​​the route included in the acquired planned route information, a threshold acquisition unit 107 that acquires a switching threshold for received radio wave intensity that causes the wireless communication unit 24 to switch to the HO-destination base station, and a threshold acquisition unit 108 that acquires a threshold for switching based on at least the location information. The device is equipped with an HO predicted area acquisition unit 108 that acquires an HO predicted area where a handover is predicted to occur on the route included in the planned route information, in which the wireless communication unit 24 switches from a base station currently connected to to another base station; an arrival time prediction unit 109 that predicts the scheduled arrival time at which the vehicle 81 will arrive in the HO predicted area; a received radio wave strength prediction unit 110 that predicts the received radio wave strength of radio waves from the base station 72 in the HO predicted area at the scheduled arrival time before arriving at the HO predicted area; and an output processing unit 112 that generates and outputs mobile communication support information based on the comparison result between the received radio wave strength predicted by the received radio wave strength prediction unit 110 and a switching threshold R0.

[0149] This allows the system to obtain information such as the HO prediction area and its expected arrival time in advance, and compare the predicted value R1 of the received radio wave strength from the HO-destination base station in the predicted HO area B with the switching threshold R0, thereby predicting the communication environment in the HO area B before a handover occurs. Then, based on the prediction result, information to support the movement or communication of the mobile unit 8 is generated and output, ensuring the reliability of wireless communication even when the communication environment changes due to a handover or the like.

[0150] In addition, in the communication system 100 according to this embodiment, when the predicted received radio wave strength is below the switching threshold value RO, the output processing unit 112 outputs information predicting a deterioration in communication quality between the wireless communication unit 24 and the base station 72 as mobile communication support information.

[0151] This allows the driver to be aware of any deterioration in communication quality in HO area B in advance, allowing the driver to respond more appropriately to changes in the communication environment and ensuring the reliability of wireless communication even when the communication environment is deteriorating.

[0152] Furthermore, in the communication system 100 according to this embodiment, when the predicted received radio wave strength is equal to or less than the switching threshold R0, the output processing unit 112 generates an avoidance route 92 that avoids the HO predicted area, and outputs the generated avoidance route 92 as mobile communication support information.

[0153] This allows the communication environment in HO area B to be predicted before handover occurs, and if it is predicted that the communication environment in HO area B will deteriorate, the vehicle 81 can choose to avoid the HO area B, allowing the vehicle 81 to continue traveling while maintaining the communication quality of wireless communication.

[0154] In addition, the communication system 100 according to this embodiment further includes an in-vehicle sensor 4 that detects driving information of the vehicle 81, and an outside-vehicle sensor 5 that detects information indicating the situation around the vehicle 81, and the output processing unit 112 generates an avoidance route 92 by taking into account the information detected by at least one of the in-vehicle sensor 4 and the outside-vehicle sensor 5.

[0155] This allows the driver to generate an avoidance route 92 that is suited to the traveling state of the vehicle 81, allowing the driver to smoothly change the route from the initial route 91 to the avoidance route 92.

[0156] In addition, the communication system 100 according to this embodiment further includes a function adjustment unit 111 that restricts the vehicle functions of the vehicle 81 when the predicted received radio wave strength is equal to or less than the switching threshold R0 and it is necessary to restrict the vehicle functions of the vehicle 81 that are executed by transmitting and receiving data to and from the outside via the wireless communication unit 24.

[0157] This allows the vehicle functions to be automatically adjusted to match the communication quality even if a deterioration in communication quality is predicted in HO area B, and the driver can be informed of the functional limitations in advance.

[0158] In addition, in the communication system 100 of this embodiment, when the output processing unit 112 outputs mobile communication support information that predicts functional restrictions on the vehicle functions of the vehicle 81 by the function adjustment unit 111, it outputs selection information as mobile communication support information to allow the driver of the vehicle 81 to select whether to continue or stop the restricted vehicle function.

[0159] This allows the driver of the vehicle 81 to know in advance whether the vehicle functions of the vehicle 81 will be restricted or stopped, allowing the driver to deal with changes in the communication environment more appropriately and ensuring the reliability of vehicle control.

[0160] Furthermore, in the communication system 100 according to this embodiment, the vehicle 81 is an autonomous driving vehicle, and the function adjustment unit 111 changes the autonomous driving level when the function for which a functional restriction of the vehicle function of the vehicle 81 is predicted is a vehicle function related to autonomous driving, and the output processing unit 112 outputs the change in the autonomous driving level as mobile communication support information before the function adjustment unit 111 changes the autonomous driving level.

[0161] As a result, even if a deterioration in communication quality is predicted in HO area B, the autonomous driving level is changed according to that communication quality, enabling appropriate autonomous driving to be adapted to the communication environment. In addition, because the driver can be aware of changes in the autonomous driving level in advance, they can respond appropriately to the changes.

[0162] In addition, in the communication system 100 according to this embodiment, when the vehicle function for which functional restriction has been predicted is a collision safety function related to autonomous driving, the output processing unit 112 outputs, as mobile communication support information, information to prompt the switching of the control mode of the vehicle 81 from automatic control to manual control.

[0163] As a result, even when traveling in HO area B, which has a communication environment in which the automatic driving functions related to the collision safety function must be stopped, the driver is notified in advance that the control of the vehicle 81 will be switched to manual, so the driver can respond appropriately to changes in the communication environment and the reliability of vehicle control can be ensured.

[0164] The communication system 100 according to this embodiment also includes an information processing device 1 having a route information acquisition unit 104, a base station information acquisition unit 105, a threshold acquisition unit 107, an HO prediction area acquisition unit 108, an arrival time prediction unit 109, a received radio wave intensity prediction unit 110, and an output processing unit 112, and a communication device 2 having a wireless communication unit 24 that performs bidirectional communication with an external communication device 7 and the information processing device 1.

[0165] As a result, by separating the communication device 2 that performs wireless communication with the external communication device 7 and the like from the information processing device 1 that performs calculation processing using various information such as prediction of the HO area B and prediction of the received radio wave strength, the processing of the communication device 2 can be specialized for wireless communication with the external communication device 7. This allows for smoother wireless communication and more reliably ensures the reliability of wireless communication even when the communication environment in the HO area B is degraded.

[0166] In addition, in the communication system 100 of this embodiment, the information processing device 1 is capable of communicating with the communication device 2, an in-vehicle sensor 4 that detects driving information of the vehicle 81, an external sensor 5 that detects the situation around the vehicle 81, and an HMI 3 that accepts input operations by the driver of the vehicle 81 and outputs information to the driver, and based on the information obtained from the communication device 2, the in-vehicle sensor 4, the external sensor 5, and the HMI 3, generates route information, predicts the HO area B, predicts the arrival time, and predicts the received radio wave strength from the base station 72 in the HO prediction area.

[0167] This makes it possible to more accurately predict the received signal strength from the HO-destination base station in the HO prediction area, thereby more reliably maintaining communication reliability even when the communication environment deteriorates.

[0168] In the communication system 100 according to this embodiment, the HMI 3 accepts input operations by the driver of a plurality of pieces of spot information used by the information processing device 1 to generate planned route information, and transmits the information to the information processing device 1.

[0169] This makes it easier to create a planned driving route for the vehicle 81.

[0170] In the communication system 100 according to this embodiment, the plurality of location information includes the departure point and destination of the vehicle 81.

[0171] This makes it easier to create a planned driving route for the vehicle 81.

[0172] In the communication system 100 according to this embodiment, the plurality of location information includes the departure point of the vehicle 81, the destination, and a stop-off point where the vehicle 81 stops before traveling from the departure point to the destination.

[0173] This increases the degree of freedom in designing the planned travel route of the vehicle 81.

[0174] In addition, in the communication system 100 of this embodiment, the multiple location information includes the current location of the vehicle 81, a first evacuation point as an evacuation point for the vehicle 81 to make an emergency stop in the event of an abnormality, and a second evacuation point which is an evacuation point different from the first evacuation point.

[0175] This means that, for example, even if the communication environment in HO area B deteriorates, there will be an evacuation point on the planned driving route, making it possible to create a safer planned driving route for, for example, the vehicle 81 that is driving automatically.

[0176] The program according to this embodiment is a program to be executed by the computers 16, 28 of the communication system 100 that is mounted on the vehicle 81 and includes a wireless communication unit 24 that transmits and receives data to and from a base station 72 via a wireless line, and that generates planned route information regarding a route that the vehicle 81 is scheduled to travel based on input information, and includes a route information acquisition step of acquiring the planned route information, a base station information acquisition step of acquiring base station information including location information of each of a plurality of base stations 72 that cover the communication area of ​​the route included in the acquired planned route information, a switching threshold acquisition step of acquiring a switching threshold of received radio wave intensity that causes the wireless communication unit 24 to switch to the HO-destination base station, and a process of acquiring at least the location information. Based on the information, the computer 16, 18 is caused to execute the following steps: an HO predicted area acquisition step for acquiring an HO predicted area where a handover is predicted to occur on the route included in the planned route information, in which the wireless communication unit 24 switches from the base station 72 to which it is currently connected to to another base station 72; an arrival time prediction step for predicting the scheduled arrival time at which the vehicle 81 will arrive in the HO predicted area; a received radio wave strength prediction step for predicting the received radio wave strength of radio waves from the base station 72 in the HO predicted area at the scheduled arrival time before arriving at the HO predicted area; and an output processing step for generating and outputting mobile communication support information based on the result of comparing the received radio wave strength predicted in the received radio wave strength prediction step with a switching threshold R0.

[0177] The communication method according to this embodiment is a communication method applied to a communication system 100 equipped with a wireless communication unit 24 mounted on a vehicle 81 and transmitting and receiving data to and from a base station 72 via a wireless line, and includes a route information acquisition step in which planned route information regarding a route that the vehicle 81 is scheduled to travel is generated based on input information, a base station information acquisition step in which base station information including position information of each of a plurality of base stations 72 that cover the communication area of ​​the route included in the acquired planned route information is acquired, a switching threshold acquisition step in which a switching threshold of received radio wave intensity that causes the wireless communication unit 24 to switch to the HO-destination base station is acquired, and a switching threshold acquisition step in which at least the position information is acquired. The method includes an HO predicted area acquisition step of acquiring an HO predicted area where a handover is predicted to occur on the route included in the planned route information, in which the wireless communication unit 24 switches from the base station 72 to which it is currently connected to another base station 72, based on the information; an arrival time prediction step of predicting the scheduled arrival time at which the vehicle 81 will arrive in the HO predicted area; a received radio wave strength prediction step of predicting the received radio wave strength of radio waves from the base station 72 in the HO predicted area at the scheduled arrival time before arriving at the HO predicted area; and an output processing step of generating and outputting mobile communication support information based on the result of comparing the received radio wave strength predicted in the received radio wave strength prediction step with a switching threshold R0.

[0178] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and can be modified as appropriate. [Explanation of symbols]

[0179] 1. Information processing equipment 2. Communications equipment 3. HMI 4 In-vehicle sensors 5. Outside vehicle sensors 8 Mobile 24 Radio Communication Department 81 Vehicle (moving object) 100 Communication Systems 103 Location information acquisition unit 104 Route information acquisition unit 105 Base station information acquisition unit 107 Threshold acquisition unit 108 Handover prediction area acquisition unit (HO prediction area acquisition unit) 109 Arrival time prediction unit 110 Received signal strength prediction unit 111 Output processing section B. Handover Area (HO Area) RO switching threshold R1 predicted value

Claims

1. A communication system equipped with a wireless communication unit that is mounted on a mobile body and transmits and receives data to and from a base station via a wireless line, a route information acquisition unit that generates route information regarding a route along which the mobile object is scheduled to travel based on input information and acquires the route information; a base station information acquisition unit that acquires base station information including location information of each of a plurality of base stations that cover a communication area of ​​the route included in the acquired route information; a threshold acquisition unit that acquires a threshold for switching the received radio wave intensity for causing the wireless communication unit to switch to a new base station as a connection destination; a handover predicted area acquisition unit that acquires, based on at least the location information, a handover predicted area in which a handover is predicted to occur in which the wireless communication unit switches from a base station currently connected to another base station along a route included in the route information; an arrival time prediction unit that predicts an arrival time at which a mobile unit will arrive in the handover prediction area; a received radio wave intensity prediction unit that predicts received radio wave intensity of radio waves from the base station in the handover prediction area at the arrival time before the handover prediction area is reached; an output processing unit that generates and outputs mobile communication support information based on a comparison result between the received radio wave strength predicted by the received radio wave strength prediction unit and the switching threshold value.

2. The communication system described in claim 1, wherein the output processing unit outputs information predicting a deterioration in communication quality between the wireless communication unit and the base station as the mobile communication support information when the predicted received radio wave strength is below the switching threshold.

3. 2. The communication system according to claim 1, wherein the output processing unit generates an avoidance route that avoids the handover predicted area when the predicted received radio wave strength is equal to or less than the switching threshold, and outputs the generated avoidance route as the mobile communication support information.

4. The vehicle further includes an in-vehicle sensor that detects movement information of the moving body, and an outside-vehicle sensor that detects information indicating a situation around the moving body, The communication system according to claim 3 , wherein the output processing unit generates the avoidance route by taking into account information detected by at least one of the in-vehicle sensor and the outside-vehicle sensor.

5. The communication system described in claim 1, further comprising a function adjustment unit that limits a function of the mobile body executed by sending and receiving data with the outside via the wireless communication unit when the predicted received radio wave strength is below the switching threshold and it is necessary to limit that function.

6. The communication system described in claim 5, wherein when the output processing unit outputs the mobile communication support information predicting the restriction of the function of the mobile body by the function adjustment unit, the output processing unit outputs selection information as the mobile communication support information to allow the driver of the mobile body to select whether to continue or stop the restricted function.

7. the moving object is an autonomous vehicle, the function adjustment unit changes the autonomous driving level when the function for which the restriction of the function of the moving body is predicted is a function related to autonomous driving; The communication system according to claim 6 , wherein the output processing unit outputs a change in the autonomous driving level as the mobile communication assistance information before the autonomous driving level is changed by the function adjustment unit.

8. The communication system described in claim 7, wherein the output processing unit outputs, as the mobile communication support information, information to prompt switching of the control mode of the moving body from automatic control to manual control when the function for which the function restriction is predicted is a collision safety function related to automatic driving.

9. an information processing device including the route information acquisition unit, the base station information acquisition unit, the threshold acquisition unit, the handover predicted area acquisition unit, the arrival time prediction unit, the received radio wave intensity prediction unit, and the output processing unit; The communication system according to claim 1 , further comprising: a communication device having the wireless communication unit for performing two-way communication with an external communication device and the information processing device.

10. the information processing device is capable of communicating with the communication device, an in-vehicle sensor that detects movement information of the mobile body, an outside sensor that detects a situation around the mobile body, and an input / output device that accepts an input operation by a driver of the mobile body and outputs information to the driver; 10. The communication system according to claim 9, wherein the route information is generated, the handover predicted area is predicted, the arrival time is predicted, and the received radio wave strength from the base station in the handover predicted area is predicted based on information acquired from the communication device, the in-vehicle sensor, the outside-vehicle sensor, and the input / output device.

11. The communication system according to claim 10 , wherein the input / output device receives input operations by a driver of a plurality of pieces of location information used in generating the route information by the information processing device, and transmits the information to the information processing device.

12. The communication system according to claim 11 , wherein the plurality of pieces of location information include a departure point and a destination point of the mobile object.

13. The communication system according to claim 11 , wherein the plurality of pieces of location information include a departure point, a destination point, and a stop-off point at which the mobile object stops before traveling from the departure point to the destination point.

14. The communication system described in claim 11, wherein the plurality of location information includes a current location of the mobile body, a first evacuation point as an evacuation point for the mobile body to make an emergency stop in the event of an abnormality, and a second evacuation point that is an evacuation point different from the first evacuation point.

15. A program executed by a computer in a communication system equipped with a wireless communication unit that is mounted on a mobile body and transmits and receives data to and from a base station via a wireless line, a route information acquisition step of generating route information relating to a route along which the mobile object is scheduled to travel based on the input information and acquiring the route information; a base station information acquisition step of acquiring base station information including location information of each of a plurality of base stations that cover a communication area of ​​the route included in the acquired route information; a switching threshold acquisition step of acquiring a switching threshold of received radio wave intensity for causing the wireless communication unit to switch to a new connection destination base station; a handover predicted area acquisition step of acquiring, based on at least the location information, a handover predicted area in which a handover is predicted to occur in which the wireless communication unit switches from a base station currently connected to another base station along a route included in the route information; an arrival time prediction step of predicting an arrival time at which a mobile unit will arrive in the handover prediction area; a received radio wave intensity prediction step of predicting received radio wave intensity of radio waves from the base station in the handover prediction area at the arrival time before the handover prediction area is reached; and an output processing step of generating and outputting mobile communication support information based on the comparison result between the received radio wave strength predicted in the received radio wave strength prediction step and the switching threshold value.

16. A communication method applied to a communication system equipped with a wireless communication unit mounted on a mobile object and transmitting and receiving data to and from a base station via a wireless line, comprising: a route information acquisition step of generating route information relating to a route along which the mobile object is scheduled to travel based on the input information and acquiring the route information; a base station information acquisition step of acquiring base station information including location information of each of a plurality of base stations that cover a communication area of ​​the route included in the acquired route information; a switching threshold acquisition step of acquiring a switching threshold of received radio wave intensity for causing the wireless communication unit to switch to a new connection destination base station; a handover predicted area acquisition step of acquiring, based on at least the location information, a handover predicted area in which a handover is predicted to occur in which the wireless communication unit switches from a base station currently connected to another base station along a route included in the route information; an arrival time prediction step of predicting an arrival time at which a mobile unit will arrive in the handover prediction area; a received radio wave intensity prediction step of predicting received radio wave intensity of radio waves from the base station in the handover prediction area at the arrival time before the handover prediction area is reached; an output processing step of generating and outputting mobile communication support information based on a comparison result between the received radio wave strength predicted in the received radio wave strength prediction step and the switching threshold value.

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