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 route information, a base station information acquisition unit 105 that acquires base station information, a threshold acquisition unit 107 that acquires a switching threshold R0, an HO prediction area acquisition unit 108 that acquires an HO prediction area, an arrival time prediction unit 109 that predicts a scheduled arrival time, a received radio wave strength prediction unit 110 that predicts the received radio wave strength from a base station 72 in the HO prediction area before arriving at the HO prediction area, and a communication control unit 111 that determines whether to transmit data to a new connection destination using multiplex transmission or to the currently connected base station 72 via a single wireless line based on the comparison result between the predicted received radio wave strength and the switching threshold R0, and transmits the data based on the determination result.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 a base station via a wireless line, the communication system including: a location information acquisition unit that acquires self-location information indicating the location of the mobile body; a route information acquisition unit that generates route information regarding a route along which the mobile body is scheduled to move 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 switching threshold of received radio wave intensity that causes the wireless communication unit to switch to a new wireless communication destination; and a handover prediction unit that acquires 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, on the route included in the route information, based on at least the location information. a received radio wave strength prediction unit that predicts the received radio wave strength of radio waves from the base station in the handover prediction area at the arrival time before the mobile body arrives at the handover prediction area; and a communication control unit that determines whether to transmit data to a new connection destination by multiplex transmission in which the same packet is transmitted via each of a plurality of different radio lines, or to transmit data to a currently connected base station via a single radio line, based on a comparison result between the received radio wave strength predicted by the received radio wave strength prediction unit and the switching threshold, a comparison result between the handover prediction area and current location information of the mobile body, or a comparison result between the arrival time predicted by the arrival time prediction unit and the current time, and transmits the data based on the determination result.

[0007] (2) In the communication system described in (1), the communication control unit transmits data to the new connection destination by multiplex transmission when the predicted received radio wave strength is below the switching threshold, and transmits the same data to the currently connected base station via one wireless line when the predicted received radio wave strength exceeds the switching threshold.

[0008] (3) In the communication system described in (2), when the predicted received radio wave strength is below the switching threshold, the communication control unit identifies multiple connection destination candidates that are candidates for the new connection destination in order of the predicted received radio wave strength, and transmits data to the multiple extracted connection destination candidates by multiplex transmission.

[0009] (4) In the communication system described in (2), when the predicted received radio wave strength is below the switching threshold, the communication control unit transmits data by multiplex transmission to the connection destination candidate with the highest predicted received radio wave strength among multiple connection destination candidates that are candidates for the new connection destination, and transmits the same data to the connection destination candidates other than the connection destination candidate with the highest predicted received radio wave strength via a single wireless line.

[0010] (5) In the communication system described in (1), the communication control unit transmits data to the new connection destination by multiplex transmission when the mobile body is located within a predetermined distance from the handover prediction area or when the current time is within a predetermined time range of the arrival time.

[0011] (6) In the communication system described in any one of (1) to (4), the communication control unit outputs forecast information to the driver of the mobile body predicting a communication failure in wireless communication when the predicted received radio wave strength is less than a communication limit value that is smaller than the switching threshold value.

[0012] (7) In the communication system described in any one of (1) to (4), when the predicted received radio wave strength is less than a communication limit value that is smaller than the switching threshold, the communication control unit outputs prediction information to the driver of the mobile body that forecasts a communication failure in wireless communication, and outputs selection information that allows the driver to choose whether to continue or stop the communication function by the wireless communication unit.

[0013] (8) In the communication system described in any one of (1) to (7), the communication system includes an information processing device having the location information acquisition unit, 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 communication control unit, and a communication device having the wireless communication unit that performs bidirectional communication with an external communication device and the information processing device.

[0014] In the communication system described in (9) and (8), 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.

[0015] (10) In the communication system described in (9), 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.

[0016] (11) In the communication system described in (10), the plurality of location information includes a departure point and a destination point of the mobile object.

[0017] (12) In the communication system described in (10), the plurality of location information includes a departure point of the mobile body, a destination point, and a stop-off point at which the mobile body stops before traveling from the departure point to the destination.

[0018] (13) In the communication system described in (10), 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.

[0019] (14) 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 includes a location information acquisition step of acquiring self-location information indicating the location of the mobile body, a route information acquisition step of generating route information regarding a route along which the mobile body is scheduled to move based on 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 the communication area of ​​the route included in the acquired route information, a threshold acquisition step of acquiring a threshold for switching received radio wave strength that causes the wireless communication unit to switch to a new wireless communication destination, and a handover predicted area where a handover is predicted to occur, in which the wireless communication unit switches from a base station currently connected to another base station, on the route included in the route information, based on at least the location information. an arrival time prediction step of predicting the arrival time of the mobile body in 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 the mobile body arrives in the handover prediction area; and a communication control step of determining, based on a result of comparing the received radio wave strength predicted in the received radio wave strength prediction step with the switching threshold, a result of comparing the handover prediction area with current location information of the mobile body, or a result of comparing the arrival time predicted in the arrival time prediction step with the current time, whether to transmit data to a new connection destination by multiplex transmission in which the same packet is transmitted via each of a plurality of different radio lines, or to transmit data to a currently connected base station via a single radio line, and transmitting the data based on the determination result.

[0020] (15) 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, the communication method including: a location information acquisition step of acquiring self-location information indicating the location of the mobile body; a route information acquisition step of generating route information regarding a route along which the mobile body is scheduled to move based on 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 covering a communication area of ​​the route included in the acquired route information; a threshold acquisition step of acquiring a switching threshold of received radio wave intensity that causes the wireless communication unit to switch to a base station that will be a new connection destination for wireless communication; and 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 another base station, on the route included in the route information, based on at least the location information. an arrival time prediction step of predicting the arrival time of the mobile body in 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 until the mobile body arrives in the handover prediction area; and a communication control step of determining, based on a result of comparing the received radio wave strength predicted in the received radio wave strength prediction step with the switching threshold, a result of comparing the handover prediction area with current location information of the mobile body, or a result of comparing the arrival time predicted in the arrival time prediction step with the current time, whether to transmit data to a new connection destination by multiplex transmission in which the same packet is transmitted via each of a plurality of different radio lines, or to transmit data to a currently connected base station via a single radio line, and transmitting the data based on the determination result. [Effects of the Invention]

[0021] According to the present invention, the reliability of wireless communication can be ensured even when the communication environment changes. [Brief explanation of the drawings]

[0022] [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] 10 is a schematic diagram showing the communication state between a communication system and a base station when there are multiple connection candidate base stations in a situation where the communication environment in an HO area is deteriorating. FIG. [Figure 10] FIG. 2 is a sequence diagram showing an example of a flow up to wireless communication control processing in a communication system according to an embodiment of the present invention. [Figure 11] 5 is a flowchart illustrating an example of a wireless communication control 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 wireless communication control 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 compatible process of the wireless communication control process 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 compatible process in the wireless communication control 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 an HO compatible process in the wireless communication control 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 compatible process in the wireless communication control process executed by the communication processing device according to one embodiment of the present invention. [Figure 17] 17 is a flowchart showing an example of a process, different from those shown in FIGS. 13 to 16, of the HO compatible process in the wireless communication control process executed by the communication processing device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] Before describing the communication system 100, an external communication device 7 that performs wireless communication with the communication system 100 will be described.

[0028] 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 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] In this embodiment, the base station 72 holds, for example, its own identification information and data relating to the communication environment (hereinafter referred to as communication environment related data). The communication environment 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] As shown in Fig. 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 processing such as multiplexed transmission of data to deal with degradation of communication quality due to handover. Note that multiplexed transmission means transmitting the same packet via multiple different wireless links.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] The I / F unit 14 is a communication interface that enables the information processing device 1 to communicate with the communication device 2, the in-vehicle sensor 4, the outside sensor 5, or the ECU 84 of the 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 that is compatible with in-vehicle communication means, such as a wire harness that performs electrical communication or an optical fiber cable that enables high-speed optical communication, or at least a part of the I / F unit 14 may be a wireless communication interface.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] The communication system 100 according to this embodiment performs wireless communication control processing to perform multiplexed data transmission by predicting the HO area B. This wireless communication control processing can ensure the reliability of communication in the HO area B.

[0067] Next, various functions that are realized by the processor 20 of the communication device 2 and that execute wireless communication control processing will be described with reference to FIG.

[0068] As shown in FIG. 7, the processor 20 of the communication device 2 includes a self-position estimation unit 201, a communication mode switching unit 202, and a communication control unit 203.

[0069] 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.

[0070] The communication mode switching unit 202 executes a process of switching the wireless communication mode between a normal mode and an HO-compatible mode based on a control signal from the information processing device 1. The normal mode is a mode in which data required to execute each of multiple functions of the vehicle 81 is transmitted over a single predetermined wireless line. The HO-compatible mode is a communication mode compatible with wireless communication in an HO area B where the communication environment is degraded, and multiplexes and transmits the data required to execute multiple functions of the vehicle 81 in accordance with HO transmission information (described later) from the information processing device 1. As a result, even when the communication environment in the HO area B is degraded, data is multiplexed and transmitted from the communication device 2 side, allowing the base station 72 to process the packet that arrived first, for example, and maintain the reliability of wireless communication.

[0071] The communication control unit 203 executes a process for controlling 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 203 controls wireless communication with the external communication device 7 according to the communication mode switched by the communication mode switching unit 202. When multiplexing and transmitting data, the communication control unit 203 copies packets by the number of wireless lines used in the multiplex transmission and transmits the copied identical packets via different wireless lines. Note that the data to be multiplexed and transmitted may be a single message including a plurality of packets in advance, or may be a single message packetized into a plurality of packets by the communication control unit 111 or the communication control unit 203.

[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 communication control 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 wireless connection destination for the communication device 2, and switches the connection to the new connection destination.

[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 destination) 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 that is a connection candidate in the HO prediction area; and information on radio wave obstructions located between the vehicle 81 and the base station 72 that is a connection candidate identified by the respective location information of the radio wave obstructions, 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] The communication control unit 111 controls the wireless communication unit 24 to execute a process of transmitting data to a new connection destination by multiplex transmission based on the comparison result between the HO prediction area and the vehicle's own position information, the comparison result between the predicted arrival time and the current time, or the comparison result between the predicted value R1 and the switching threshold R0. Note that the new connection destination may not only be the base station 72, but also, for example, a communication device of another vehicle 82, a roadside unit, a satellite system 73, a drone 74, etc.

[0086] For example, the communication control unit 111 may compare the HO prediction area with the current location information of the vehicle 81 acquired by the location information acquisition unit 103, and when the vehicle 81 enters the HO prediction area, transmit data to the HO-destination base station by multiplex transmission. When the vehicle 81 is outside the HO prediction area, the communication control unit 111 may transmit data related to one function to the HO-destination base station via one wireless line (hereinafter referred to as transmission via one line). Furthermore, 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 communication control unit 111 may multiplex and transmit data to a new connection destination. The predetermined distance may be set, for example, depending on the communication area A of the base station 72, the vehicle speed of the vehicle 81, vehicle functions subject to function restrictions, etc. The predetermined distance may be set, for example, to 30 m if the vehicle 81 is traveling at a speed within the legal limit, or 120 m if traveling at a higher speed.

[0087] The communication control unit 111 may compare the expected arrival time with the current time, and if the current time is at or near the expected arrival time, may multiplex and transmit the data to the new connection destination.

[0088] For example, when the predicted value R1 is equal to or less than the switching threshold R0, the communication control unit 111 may multiplex and transmit data to a new connection destination in the HO prediction area or its vicinity, and when the predicted value R1 exceeds the switching threshold R0, the communication control unit 111 may transmit data to the currently connected base station 72 via a single line.

[0089] 9 is a schematic diagram showing a communication state between the communication system 100 and the base station 72 when there are multiple connection destination candidates in a situation where the communication environment in HO area B has deteriorated. The communication control unit 111 may identify multiple connection destination candidates, for example, when the predicted value R1 is equal to or less than the switching threshold R0. For example, in the example shown in FIG. 9, the communication control unit 111 may identify the base station 72B and the base station 72C as the connection destination candidates. Then, data may be multiplexed and transmitted to the base station 72 with the highest predicted value R1 among the identified connection destination candidates, and data may be transmitted to the other connection destination candidates over a single line.

[0090] Furthermore, for example, when the predicted value R1 is equal to or less than the switching threshold R0, the communication control unit 111 may identify multiple connection destination candidates whose predicted value R1 is lower than the switching threshold R0 but higher than a predetermined threshold (hereinafter referred to as the communication limit value), and multiplex and transmit data to the identified multiple connection destination candidates. Note that when the communication control unit 111 cannot identify a connection destination candidate higher than the communication limit value, that is, when no connection destination candidate is found, it notifies the output processing unit 113 to that effect.

[0091] When the output processing unit 112 receives a notification from the communication control unit 111 that no connection destination candidate has been found, it outputs forecast information for forecasting a communication failure to the driver of the vehicle 81. After outputting the forecast information of the communication failure, the output processing unit 112 may output selection information for allowing the driver of the vehicle 81 to select whether to continue or stop the communication function of the vehicle 81 and the communication device 2.

[0092] 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 until traveling through the HO predicted area will be described with reference to Fig. 10. Fig. 10 is a sequence diagram showing an example of the processing flow from input of point information by the driver until traveling through the HO predicted area.

[0093] 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.

[0094] In step S102, the HMI 3 transmits the location information received in step S101 to the information processing device 1.

[0095] In step S103 , the communication device 2 transmits the map information received from the control server 71 to the information processing device 1 .

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] In step S109, the information processing device 1 predicts the received radio wave strength of radio waves from the currently 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.

[0102] 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 the data transmission method in the HO prediction area based on the comparison result. Specifically, the information processing device 1 determines whether to transmit data by multiplex transmission or by single line transmission.

[0103] In step S111, the information processing device 1 transmits to the communication device 2 transmission control information indicating the data transmission method determined in step S111.

[0104] In step S112, the communication device 2 transmits data required for executing the vehicle functions via each wireless line in multiplex transmission or on a single line in accordance with the transmission control information transmitted in step S113.

[0105] In step S113, the communication device 2 transmits to the information processing device 1 data required to execute each function of the vehicle 81, which data has been received from the currently connected base station 72 or the new connection destination.

[0106] In step S114, the information processing device 1 transmits to the HMI 3 the data transmitted from the communication device 2 in step S113.

[0107] In step S115, the HMI 3 outputs the data transmitted from the information processing device 1 in step S114 to a display or the like.

[0108] Next, an example of wireless communication control processing executed by the communication processing device 6 will be described with reference to FIGS.

[0109] First, the overall flow of the wireless communication control process will be described with reference to Fig. 11. Fig. 11 is a flowchart showing an example of the wireless communication control process executed by the communication processing device 6.

[0110] As shown in FIG. 11, in step S10, the processor 10 of the information processing device 1 executes the HO prediction process.

[0111] 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.

[0112] In step S30, the processor 10 and the processor 20 execute the HO handling process.

[0113] In step S22, the processor 10 or 20 of the communication processing device 6 determines whether the host vehicle 81 has arrived at the HO prediction area and is now a predetermined distance away from the HO prediction area. If the processor 10 or 20 determines that the host vehicle 81 has moved the predetermined distance away (step S22; YES), the processor 10 or 20 switches the communication mode of the communication device 2 from the HO-compatible mode to the normal mode (step S60), and then ends the wireless communication control process. On the other hand, if the processor 10 or 20 determines that the host vehicle 81 has not moved the predetermined distance away (step S22; NO), the processor 10 or 20 repeats the process of step S22 after a predetermined time has elapsed.

[0114] Next, the HO prediction process in step S10 of the wireless communication control 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.

[0115] 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.

[0116] 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.

[0117] 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.

[0118] In step S14, the base station information acquisition unit 105 acquires base station information of the base station 72 that covers the communication area of ​​the route included in the planned route information generated in step S13.

[0119] 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.

[0120] 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.

[0121] 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.

[0122] 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.

[0123] Next, the HO response process in step S30 of the wireless communication control process will be described with reference to Fig. 13. Fig. 13 is a flowchart showing an example of the HO response process executed by the information processing device 1 and the communication device 2.

[0124] 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 the currently connected base station 72 or the HO-destination base station and another vehicle 82 or other external communication device, position information and number of radio wave obstructions such as moving objects 8 and buildings existing between the base station 72 and the vehicle 81, and weather information.

[0125] 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 the predicted value R1.

[0126] 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.

[0127] In step S34, the communication control unit 111 compares the switching threshold value read in step S33 with the predicted value R1 predicted in step S32. If the communication control unit 111 determines that the predicted value R1 is equal to or less than the switching threshold value R0 (step S34; YES), the communication control unit 111 generates transmission control information for controlling the wireless communication unit 24 to multiplex and transmit data to the new connection destination, and transmits the information to the communication device 2 (step S35). As a result, the communication device 2 multiplexes and transmits data to the new connection destination in the HO prediction area or its vicinity in accordance with the received transmission control information. On the other hand, if the communication control unit 111 determines that the predicted value R1 exceeds the switching threshold value R0 (step S34; NO), the communication control unit 111 generates transmission control information for controlling the wireless communication unit 24 to transmit data to the currently connected base station 72 over a single line, and transmits the information to the communication device 2 (step S36). As a result, the communication device 2 transmits data to the currently connected base station 72 over a single line in accordance with the received transmission control information.

[0128] Next, an example of a processing flow of the HO response 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. 11, and therefore description thereof will be omitted.

[0129] As shown in FIG. 14, in step S34, if the communication control unit 111 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 S37.

[0130] In step S37, communication control unit 111 identifies a plurality of connection destination candidates whose predicted value R1 acquired in step S32 is higher than the communication limit value.

[0131] In step S38, the communication control unit 111 generates transmission control information for controlling multiplexed transmission of data to the multiple connection destination candidates identified in step S37, and transmits the generated transmission control information to the communication device 2. As a result, the communication device 2 multiplexes and transmits data to each of the multiple connection destination candidates in the HO prediction area or its vicinity in accordance with the received transmission control information.

[0132] Next, an example of a processing flow of the HO response processing that is different from the examples shown in Figures 13 and 14 will be described with reference to Figure 15. Note that the processing of steps S31 to S33 and S36 shown in Figure 15 is the same as the example shown in Figure 11, and therefore description thereof will be omitted.

[0133] As shown in FIG. 15, in step S34, if the communication control unit 111 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 S37.

[0134] In step S37, communication control unit 111 identifies a plurality of connection destination candidates whose predicted value R1 acquired in step S32 is higher than the communication limit value.

[0135] The loop process from step S70 is executed at predetermined time intervals for all the connection destination candidates identified in step S37.

[0136] In step S71, communication control unit 111 selects one connection destination candidate from the plurality of connection destination candidates identified in step S37.

[0137] In step S72, the communication control unit 111 determines whether the predicted value R1 of the received radio wave strength of the radio waves from the connection destination candidate selected in step S71 is the highest among the multiple connection destination candidates identified in step S37. If the communication control unit 111 determines that the received radio wave strength of the radio waves from the connection destination candidate selected in step S71 is the highest (step S72; YES), it decides to multiplex and transmit data to the selected connection destination candidate (step S73). On the other hand, if the communication control unit 111 determines that the received radio wave strength of the radio waves from the connection destination candidate selected in step S71 is not the highest (step S72; NO), it decides to transmit data to the selected connection destination candidate over a single line (step S74).

[0138] In step S39, the communication control unit 111 generates transmission control information for controlling the method of transmitting data to each connection destination candidate of the wireless communication unit 24, in accordance with the result of the determination of the data transmission method determined by the loop processing from step S70.

[0139] Next, an example of a processing flow of the HO response 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 and S36 shown in Figure 16 is the same as the example shown in Figure 11, and therefore description thereof will be omitted.

[0140] As shown in FIG. 16, in step S34, if the communication control unit 111 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 S41.

[0141] In step S41, the communication control unit 111 determines whether the predicted value R1 is equal to or less than the communication limit value. If the communication control unit 111 determines that the predicted value R1 exceeds the communication limit value (step S41; NO), the communication control unit 111 generates transmission control information for controlling the wireless communication unit 24 to multiplex and transmit data to the new connection destination, and transmits the information to the communication device 2 (step S44). As a result, the communication device 2 multiplexes and transmits data to the new connection destination in the HO prediction area or its vicinity in accordance with the received transmission control information. On the other hand, if the communication control unit 111 determines that the predicted value R1 is equal to or less than the communication limit value (step S41; YES), the process proceeds to step S42.

[0142] In step S42, the output processing unit 112 outputs to the HMI 3 forecast information that forecasts a communication failure to the driver of the vehicle 81.

[0143] In step S43, 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 communication function of the wireless communication unit 24.

[0144] Next, an example of a processing flow of the HO handling processing that is different from the example shown in FIGS. 13 to 16 will be described with reference to FIG.

[0145] As shown in FIG. 17, in step S45, the position information acquisition unit 103 acquires the current location information of the vehicle 81.

[0146] In step S46, the communication control unit 111 determines whether the location indicated by the current location information acquired in step S45 is within the HO prediction area acquired in step S16 or its vicinity. If the communication control unit 111 determines that the location of the vehicle 81 indicated by the current location information is within the HO prediction area or its vicinity (step S46; YES), the communication control unit 111 generates transmission control information for controlling the wireless communication unit 24 to multiplex and transmit data to the HO-destination base station, and transmits the information to the communication device 2 (step S47). As a result, the communication device 2 multiplexes and transmits data to a new connection destination in the HO prediction area or its vicinity in accordance with the received transmission control information. On the other hand, if the communication control unit 111 determines that the location of the vehicle 81 indicated by the current location information is not within the HO prediction area or its vicinity (step S46; NO), the communication control unit 111 generates transmission control information for controlling the wireless communication unit 24 to transmit data to the currently connected base station 72 over a single line, and transmits the information to the communication device 2 (step S48). As a result, the communication device 2 transmits data to the currently connected base station 72 over a single line in accordance with the received transmission control information.

[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 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 location information acquisition unit 103 that acquires self-location information indicating the location of the vehicle 81, a route information acquisition unit 104 that generates route information relating to a route along which the vehicle 81 is scheduled to travel based on input information and acquires the route 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 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 a new wireless communication connection destination, and a handover initiation unit 108 that switches the base station 72 to which the wireless communication unit 24 is currently connected to another base station 72 on the route included in the planned route information, based on at least the location information of the base station 72. an arrival time prediction unit 109 that predicts the estimated arrival time at which the vehicle 81 will arrive in the HO prediction 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 prediction area at the estimated arrival time before arriving in the HO prediction area; and a communication control unit 111 that determines whether to transmit data to a new destination by multiplex transmission in which the same packet is transmitted via each of a plurality of different wireless lines, or to transmit data to the currently connected base station 72 via a single wireless line, 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, the comparison result between the HO prediction area and current position information of the vehicle 81, or the comparison result between the estimated arrival time predicted by the arrival time prediction unit 109 and the current time, and transmits the data based on the determination result.

[0149] This allows data transmission by multiplex transmission in areas where a drop in communication quality due to handover is expected, allowing the base station 72 to perform processing such as adopting the packet that arrived first from the terminal side, that is, the communication device 2. Therefore, even if the communication environment changes due to handover or the like, the reliability of wireless communication can be ensured, and for example, the reliability of vehicle control or assistance is improved.

[0150] Furthermore, in the communication system 100 according to this embodiment, when the predicted value R1 is equal to or less than the switching threshold R0, the communication control unit 111 transmits data to the new connection destination by multiplex transmission, and when the predicted value R1 exceeds the switching threshold R0, it transmits the same data to the currently connected base station 72 via one wireless line.

[0151] 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 currently connected base station 72 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, multiplex transmission or single-line transmission is selected according to the prediction result, so multiplex transmission is performed as needed, ensuring the reliability of wireless communication while enabling more efficient data transmission.

[0152] Furthermore, in the communication system 100 according to this embodiment, when the predicted value R1 is equal to or less than the switching threshold value R0, the communication control unit 111 identifies multiple connection destination candidates that are candidates for a new connection destination in descending order of predicted value R1, and transmits data to the extracted multiple connection destination candidates by multiplex transmission.

[0153] As a result, even if the communication environment in the HO area B is expected to deteriorate, multiplexed transmission to a plurality of base stations 72 can further reduce the possibility of communication interruptions or delays.

[0154] Furthermore, in the communication system 100 according to this embodiment, when the predicted value R1 is equal to or less than the switching threshold value R0, the communication control unit 111 transmits data by multiplex transmission to the connection destination candidate with the highest predicted value R1 among multiple connection destination candidates that are candidates for the new connection destination, and transmits the same data via a single wireless line to the connection destination candidates other than the connection destination candidate with the highest predicted value R1.

[0155] As a result, even if a deterioration in the communication environment in HO area B is expected, multiplex transmission is performed to the base station 72 with the highest received radio wave strength among multiple connection destination candidates, thereby further reducing the possibility of communication interruptions or delays.

[0156] In addition, in the communication system 100 according to this embodiment, the communication control unit 111 transmits data to a new connection destination by multiplex transmission when the vehicle 81 is located within a predetermined distance from the HO prediction area or when the current time is within a predetermined time range of the scheduled arrival time.

[0157] This allows data to be multiplexed and transmitted in HO area B, where communication quality tends to deteriorate, thereby more reliably ensuring the reliability of wireless communication.

[0158] In addition, in the communication system 100 of this embodiment, when the predicted value R1 is less than a communication limit value that is smaller than the switching threshold value R0, the communication control unit 111 outputs forecast information to the driver of the vehicle 81, forecasting poor wireless communication.

[0159] This allows the driver to be aware of communication problems 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 during communication problems.

[0160] In addition, in the communication system 100 according to this embodiment, when the predicted value R1 is less than a communication limit value that is smaller than the switching threshold value R0, the communication control unit 111 outputs prediction information to the driver of the vehicle 81 to warn of a communication failure in wireless communication, and also outputs selection information to allow the driver to select whether to continue or stop the communication function by the wireless communication unit 24.

[0161] 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.

[0162] The communication system 100 according to this embodiment also includes an information processing device 1 having a location information acquisition unit 103, 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 a communication control unit 111, 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.

[0163] 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.

[0164] 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.

[0165] 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.

[0166] In the communication system 100 according to this embodiment, the HMI 3 accepts input operations by the driver of a plurality of point information used for generating planned route information by the information processing device 1, and transmits the information to the information processing device 1.

[0167] This makes it easier to create a planned driving route for the vehicle 81.

[0168] In the communication system 100 according to this embodiment, the plurality of location information includes the departure point and destination of the vehicle 81.

[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 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.

[0171] This increases the degree of freedom in designing the planned travel route of the vehicle 81.

[0172] 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.

[0173] 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.

[0174] The program according to this embodiment is a program to be executed by the computers 16 and 28 of the communication system 100 that is mounted on the vehicle 81 and has a wireless communication unit 24 that transmits and receives data to and from a base station 72 via a wireless line, and includes a location information acquisition step of acquiring own location information that indicates the location of the vehicle 81; a route information acquisition step of generating planned route information regarding a route that the vehicle 81 is scheduled to travel based on input information and 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 threshold acquisition step of acquiring a threshold for switching the received radio wave intensity that causes the wireless communication unit 24 to switch to a new wireless communication destination; and a step of switching the base station 72 to which the wireless communication unit 24 is currently connected to to another base station 72 on the route included in the planned route information based on at least the location information of the base station 72. the computer 16, 28 executes an HO predicted area acquisition step of acquiring an HO predicted area in which a handover is predicted to occur, an arrival time prediction step of predicting an estimated 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 estimated arrival time before arriving in the HO predicted area, and a communication control step of determining, based on a result of comparing the received radio wave strength predicted in the received radio wave strength prediction step with a switching threshold R0, a result of comparing the HO predicted area with current location information of the vehicle 81, or a result of comparing the arrival time predicted in the arrival time prediction step with the current time, whether to transmit data to a new connection destination by multiplex transmission in which the same packet is transmitted via each of a plurality of different radio lines, or to transmit data to the currently connected base station 72 via a single radio line, and transmitting the data based on the determination result.

[0175] 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 location information acquisition step of acquiring own location information indicating the location of the vehicle 81, a route information acquisition step of generating planned route information regarding a route that the vehicle 81 is scheduled to travel based on input information and 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 threshold acquisition step of acquiring a switching threshold for received radio wave intensity that causes the wireless communication unit 24 to switch to a base station 72 that will be a new connection destination for wireless communication, and a step of switching the base station 72 to which the wireless communication unit 24 is currently connected to another base station 72 on the route included in the planned route information based on at least the location information of the base station 72. 2, a HO prediction area acquisition step of acquiring an HO prediction area in which a handover to switch to base station 72 is predicted to occur; an arrival time prediction step of predicting an estimated arrival time at which host vehicle 81 will arrive in the HO prediction area; a received radio wave strength prediction step of predicting the received radio wave strength of radio waves from base station 72 in the HO prediction area at the estimated arrival time before arriving in the HO prediction area; and a communication control step of determining, based on a result of comparing the received radio wave strength predicted in the received radio wave strength prediction step with a switching threshold R0, a result of comparing the HO prediction area with current location information of host vehicle 81, or a result of comparing the estimated arrival time predicted in the arrival time prediction step with the current time, whether to transmit data to a new connection destination by multiplex transmission in which the same packet is transmitted via each of a plurality of different radio lines, or to transmit data to the currently connected base station 72 via a single radio line, and transmitting the data based on the determination result.

[0176] 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]

[0177] 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 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 Communication control unit B. Handover Area (HO Area)

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 location information acquisition unit that acquires self-location information indicating the location of a moving object; 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 switching threshold for received radio wave intensity that causes the wireless communication unit to switch to a new wireless communication connection; 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; and an arrival time prediction unit that predicts an arrival time at which the mobile object 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; and a communication control unit that determines whether to send data to a new connection destination by multiplex transmission, in which the same packet is transmitted via each of a plurality of different wireless links, or to send data to a currently connected base station via a single wireless link, based on the result of comparing the received radio wave strength predicted by the received radio wave strength prediction unit with the switching threshold, the result of comparing the handover prediction area with the current location information of the mobile body, or the result of comparing the arrival time predicted by the arrival time prediction unit with the current time, and transmits the data based on the result of the determination.

2. The communication system described in claim 1, wherein the communication control unit transmits data to the new connection destination by multiplex transmission when the predicted received radio wave strength is below the switching threshold, and transmits the same data to the currently connected base station via a single wireless line when the predicted received radio wave strength exceeds the switching threshold.

3. The communication system described in claim 2, wherein when the predicted received radio wave strength is below the switching threshold, the communication control unit identifies multiple connection destination candidates that are candidates for the new connection destination in order of the highest predicted received radio wave strength, and transmits data to the extracted multiple connection destination candidates via multiplex transmission.

4. The communication system described in claim 2, wherein, when the predicted received radio wave strength is below the switching threshold, the communication control unit transmits data by multiplex transmission to the connection destination candidate with the highest predicted received radio wave strength among multiple connection destination candidates that are candidates for the new connection destination, and transmits the same data via a single wireless line to the connection destination candidates other than the connection destination candidate with the highest predicted received radio wave strength.

5. The communication system according to claim 1, wherein the communication control unit transmits data to the new connection destination by multiplex transmission when the mobile unit is located within a predetermined distance from the handover prediction area or when the current time is within a predetermined time range of the arrival time.

6. The communication system described in claim 1, wherein the communication control unit outputs forecast information to the driver of the mobile body predicting a wireless communication failure when the predicted received radio wave strength is less than a communication limit value that is smaller than the switching threshold.

7. The communication system according to claim 1, wherein the communication control unit outputs prediction information to the driver of the mobile body that forecasts a communication failure in wireless communication when the predicted received radio wave strength is less than a communication limit value that is smaller than the switching threshold, and outputs selection information that allows the driver to choose whether to continue or stop the communication function of the wireless communication unit.

8. an information processing device including the location information acquisition unit, 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 communication control 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.

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 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; 9. The communication system according to claim 8, 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.

10. The communication system according to claim 9 , wherein the input / output device receives an input operation 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.

11. The communication system according to claim 10 , wherein the plurality of pieces of location information include a departure point and a destination point of the mobile object.

12. The communication system according to claim 10 , 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.

13. The communication system described in claim 10, 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.

14. A program to be executed by a computer of 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 location information acquisition step of acquiring self-location information indicating the location of the moving body; 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 threshold value acquisition step of acquiring a switching threshold value for received radio wave intensity that causes the wireless communication unit to switch to a new wireless communication connection; 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 the 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 a communication control process for determining whether to send data to a new destination by multiplex transmission, in which the same packet is transmitted via each of a plurality of different wireless lines, or to send data to a currently connected base station via a single wireless line, based on the result of comparing the received radio wave strength predicted in the received radio wave strength prediction process with the switching threshold, the result of comparing the handover prediction area with the current location information of the mobile body, or the result of comparing the arrival time predicted in the arrival time prediction process with the current time, and transmitting the data based on the result of the determination.

15. 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 location information acquisition step of acquiring self-location information indicating the location of the moving body; 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 threshold acquisition step of acquiring a threshold for switching the received radio wave intensity for causing the wireless communication unit to switch to a base station that will be a new connection destination of wireless communication; 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 the 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 a communication control step of determining whether to transmit data to a new connection destination by multiplex transmission, in which the same packet is transmitted via each of a plurality of different wireless links, or to transmit data to a currently connected base station via a single wireless link, based on a comparison result between the received radio wave strength predicted in the received radio wave strength prediction step and the switching threshold, a comparison result between the handover prediction area and current location information of the mobile body, or a comparison result between the arrival time predicted in the arrival time prediction step and the current time, and transmitting the data based on the determination result.

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