JP7315751B2 - Server, communication system, communication method and program - Google Patents

Description

The present invention relates to a server, a communication system, a communication device, a communication method, and a program that can be used for distributing information to mobile objects such as a plurality of vehicles.

2. Description of the Related Art Conventionally, a system is known in which direct wireless communication is performed between mobile bodies such as a plurality of vehicles. For example, Patent Literature 1 describes an inter-vehicle communication system that includes a plurality of mobile station communication devices each having a wide area communication terminal and an inter-vehicle communication device, and a base station communication device capable of wide area communication with the wide area communication terminal.

JP 2013-118522 A

However, in the conventional system described above, if information is to be transmitted from the base station communication device to each of a plurality of mobile station communication devices in a short period of time, the downlink traffic from the base station communication device (wireless communication relay device) may increase rapidly in a short period of time. Further, when a plurality of vehicles attempt to relay information through inter-vehicle communication, there is a risk that the relay of the information will be interrupted depending on the inter-vehicle distance.

The server according to the constitution of the present invention is a server that distributes information to multiple mobile enthusiasts, and the distribution area determination department that determines the distribution area located by the multiple mobilizers to be distributed, and the unicast transmission vs. transmission via the base station of mobile communication based on the location information of the multiple mobile enthusiasts in the distribution area. It is equipped with a transmission target unit that selects an elephant's mobile body and determines, and an information transmission unit that unicasted the information is sent to the moving body to the unicast transmission target via the base station of the mobile communication.

A server according to another aspect of the present invention is a server for distributing information to a plurality of mobile bodies, and comprises a distribution area determination unit that determines a distribution area in which a plurality of mobile bodies to which information is to be distributed are located, and based on at least one of the content of information to be distributed and location information of the plurality of mobile bodies positioned within the distribution area, selects a distribution system to be used when distributing the information to each of the plurality of mobile bodies located within the distribution area, from a plurality of types of distribution systems including at least wireless communication via a mobile communication base station. a selection unit; and an information distribution unit that distributes the information to the plurality of mobile units via the base station using the selected wireless distribution method.
The multiple types of distribution methods may include a first distribution method and a second distribution method. A first distribution method is a distribution method that selects and determines a mobile object for unicast transmission via a mobile communication base station based on the position information of the plurality of mobile objects located within the distribution area, and unicast-transmits the information to the mobile object for unicast transmission via the mobile communication base station. A second distribution method is a distribution method in which the information is unicast-transmitted to each of the plurality of mobile units located within the distribution area via the base station.

In the server, the information received by the mobile object for unicast transmission may be broadcast by direct wireless communication to other mobile objects located in the vicinity of the mobile object for unicast transmission.
In the server, the information to be transmitted to the mobile object subject to unicast transmission may include transfer necessity information indicating whether or not to transfer the information to the surrounding mobile object by broadcast transmission.
In the server, the mobiles targeted for unicast transmission may include at least one of mobiles in which other mobiles that are capable of direct wireless communication are not located nearby and mobiles that do not have a direct wireless communication function between mobiles.
In the server, the targets of unicast transmission from the server via the base station may include roadside communication relay devices provided around the moving route of the distribution area, and the mobile bodies to be the targets of unicast transmission may be selected and determined based on the position information of the plurality of mobile bodies located within the distribution area and the position information of the roadside communication relay devices.
In the server, at least one of a communicable distance and communication power of direct wireless communication between mobiles, a spatial density of the plurality of mobiles, and a time zone may be used to determine the mobiles to be the targets of unicast transmission.
In the server, the information distributed to the plurality of mobile units may include at least one of time stamp information and information enabling identification of necessity of output of distribution information.
The server may include an information acquisition unit that receives and acquires the position and speed of the mobile units and information on the presence or absence of a direct wireless communication function between the mobile units from the plurality of mobile units via the base station, and an information storage unit that stores the position information of each of the plurality of mobile units.
In the server, the mobile object may be a vehicle traveling on a road.
The server may include a dangerous event information receiving unit that receives information about the dangerous event from a moving object that has detected a dangerous event occurring in an area in which the plurality of moving objects are moving, the information to be distributed may be information about the dangerous event, and the distribution area may be an area on the upstream side in the moving direction of the moving object from the position where the dangerous event has occurred.

A communication system according to still another aspect of the present invention includes any of the servers described above and a base station for mobile communication.
The communication system may further include a roadside communication relay device that is provided in the vicinity of the moving route of the mobile body and that is capable of unicast transmission of information from the server via the base station, and the information received by the roadside communication relay device may be broadcast directly to mobile bodies located in the vicinity of the roadside communication relay device by wireless communication.

A communication apparatus according to still another aspect of the present invention is a communication apparatus provided in a mobile body, which receives a first wireless communication unit that communicates with a server via a mobile communication base station, a second wireless communication unit that directly wirelessly communicates with a surrounding mobile unit, receives distribution information from the server, and transfer necessity information that instructs whether or not to perform transfer by broadcasting the distribution information to the surrounding mobile units via the direct wireless communication, and if the transfer necessity information indicates transfer necessity, the distribution information via the direct wireless communication. to surrounding mobile bodies, and controls not to perform broadcast transmission of the distribution information by the direct wireless communication when the transfer necessity information indicates that the transfer is unnecessary.

A communication device according to still another aspect of the present invention is a communication device provided in a mobile body, comprising: a first wireless communication unit that communicates with a server via a mobile communication base station; a second wireless communication unit that performs direct wireless communication with a nearby mobile unit; the first wireless communication unit that receives first distribution information transmitted from the server; the second wireless communication unit that receives second distribution information transferred from the surrounding mobile unit; and an information processing control unit that controls to store the first distribution information and the second distribution information when the result is a mismatch, and to discard one of the first distribution information and the second distribution information and store the other when the comparison result is a match.

A communication device according to still another aspect of the present invention is a communication device provided in a mobile body, comprising: a first wireless communication unit that communicates with a server via a mobile communication base station; a second wireless communication unit that performs direct wireless communication with a roadside communication relay device provided around a moving route; the first wireless communication unit receives first distribution information transmitted from the server; an information processing control unit that compares information with distribution information received from the roadside communication relay device, stores the two distribution information when the two distribution information do not match, and controls to discard one of the two distribution information and store the other when the two distribution information matches.

A communication method according to still another aspect of the present invention is a communication method for distributing information to a plurality of mobiles, comprising: determining a distribution area in which a plurality of mobiles targeted for information distribution are located; selecting and determining mobiles targeted for unicast transmission via a mobile communication base station based on location information of the plurality of mobiles located within the distribution area; and unicast-transmitting the information to the mobiles targeted for unicast transmission via the base station for mobile communication.

A communication method according to still another aspect of the present invention is a communication method for distributing information to a plurality of mobile units, wherein a distribution area in which a plurality of mobile units to which information is to be distributed is located is determined, and based on at least one of the content of information to be distributed and location information of the plurality of mobile units located within the distribution area, a distribution method to be used when distributing the information to each of the plurality of mobile units located within the distribution area is selected from a plurality of types of distribution methods including at least wireless communication via a mobile communication base station. and delivering the information to the plurality of mobiles via the base station using the selected wireless delivery scheme.

A program according to still another aspect of the present invention is a program to be executed by a computer or processor provided in an apparatus for distributing information to a plurality of mobiles, comprising: program code for determining a distribution area in which a plurality of mobiles targeted for information distribution are located; program code for selecting and determining mobiles targeted for unicast transmission via a mobile communication base station based on location information of the plurality of mobiles positioned within the distribution area; and unicast transmission of the information to the mobiles targeted for unicast transmission via the mobile communication base station. including program code;

A program according to still another aspect of the present invention is a program executed by a computer or processor provided in an apparatus for distributing information to a plurality of mobile bodies, wherein the program code determines a distribution area in which a plurality of mobile bodies to which information is to be distributed are located, and distributes the information to each of the plurality of mobile bodies positioned within the distribution area from a plurality of types of distribution methods including at least wireless communication via a mobile communication base station based on at least one of the content of the information to be distributed and position information of the plurality of mobile bodies positioned within the distribution area. and program code for distributing the information to the plurality of mobile units via the base station using the selected wireless distribution method.

According to the present invention, information can be distributed via a base station to a plurality of moving bodies moving in a target distribution area while suppressing a rapid increase in downlink traffic from a base station for mobile communication.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing an example of the overall configuration of an information distribution system for distributing dangerous event information according to this embodiment; FIG. 2 is a block diagram showing an example of main functions of the server according to the embodiment; FIG. 2 is a block diagram showing an example of main functions of the vehicle communication device according to the present embodiment; FIG. 4 is a sequence diagram showing an example of dangerous event information distribution processing according to the embodiment; FIG. 2 is an explanatory diagram showing another example of the overall configuration of the information distribution system according to the embodiment; FIG. 11 is a sequence diagram showing another example of delivery processing of dangerous event information according to the present embodiment; FIG. FIG. 4 is a block diagram showing another example of main functions of the server according to the embodiment; FIG. 5 is an explanatory diagram showing still another example of the overall configuration of the information distribution system according to the present embodiment; FIG. 11 is a sequence diagram showing still another example of the dangerous event information delivery process according to the present embodiment;

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is an explanatory diagram showing an example of the overall configuration of an information distribution system for distributing dangerous event information according to this embodiment. In the information distribution system of the present embodiment, when one vehicle 31 among a plurality of vehicles 31 to 38 and 41 to 49 running in lanes 91 and 92 of a road 90 as a moving route detects a dangerous event, the dangerous event information can be distributed to a plurality of following vehicles 32 to 38 traveling in a predetermined distribution area A behind the vehicle 31 that has detected the dangerous event, so that the occurrence of the dangerous event can be promptly notified. In particular, the information distribution system of this embodiment is suitable for the case where, when a large number of vehicles are traveling on an expressway, it is necessary to quickly distribute and notify the rear vehicles of information on a dangerous event that has occurred in front.

Here, a dangerous event is an event that may affect a vehicle traveling in the position of occurrence, such as a traffic accident on the road 90, a vehicle fire, falling objects, sudden congestion, an abnormally stopped vehicle, a vehicle running in the wrong direction, a landslide, a flood, or a localized torrential rain.

Vehicles in the present embodiment are automobiles such as passenger cars, trucks, and buses, and the present invention is not limited to the type and number of vehicles. The present invention can also be applied to a case in which the mobile object to which information is to be distributed is a mobile object other than a vehicle, such as an aircraft or a ship that moves along a set movement route in the sky or on water.

In FIG. 1, the information distribution system of this embodiment includes a server 10 that distributes dangerous event information to a plurality of vehicles traveling on a road 90 . The server 10 of the present embodiment is, for example, provided in the base station 16 of the mobile communication network 15, and is an MEC (Multi-access Edge Computing) device capable of processing various data transmitted and received between the communication devices of the vehicles 31 to 38 and 41 to 49 via the base station 16. The server 10, which is an MEC device, may be provided at a node between the base station 16 and the core network of the mobile communication network 15 or outside the core network.

A base station 16 forms one or more cells (sectors, also called sector cells). The cells may be two-dimensionally formed on the ground or the sea, or three-dimensionally formed from the sky toward the ground or the sea. A cell may be a macrocell, a small cell, a femtocell, a picocell, a large cell, and so on. A plurality of cells may constitute a cellular structure distributed so as to be adjacent to each other two-dimensionally or three-dimensionally, or may constitute a hierarchical cell structure in which some or all of them are hierarchically overlapped. The base station 16 may be a macrocell base station, a small cell base station, a femtocell base station, a picocell base station, a large cell base station, a fixed base station fixedly installed on the ground or the like, or a mobile base station capable of moving on the ground, on the sea, in the sky, or the like. The base station 16 may be a wireless communication device called eNodeB (evolved Node B: eNB), gNodeB (gNB), en-NodeB (en-gNB), access point, or the like.

The communication devices of the vehicles 31-38 and 41-49 are equipped with user equipment (hereinafter referred to as "UE") that constitutes a network communication unit that can be used as a subscriber of mobile communication services. The UE may be a wireless communication device, also called a user terminal, terminal, terminal device, mobile station, mobile device, or the like. Each of the UEs of the vehicles 31 to 38 and 41 to 49 may be a device that is carried by the user in each vehicle, or a device that is installed in each vehicle (for example, a device that is incorporated as part of the navigation device).

UEs of vehicles 31 to 38 and 41 to 49 can communicate with the server 10 via the base station 16, and transmit vehicle information to the server 10 periodically or irregularly. The vehicle information includes, for example, position information indicating the current positions of the vehicles 31 to 38 and 41 to 49 (UE), speed V of the vehicles 31 to 38 and 41 to 49 (UE), vehicle identification information (vehicle ID), and presence/absence information of inter-vehicle communication functions. The velocities V of the vehicles 31-38, 41-49 can be obtained from, for example, the drive control device of the vehicle. The velocities V of the vehicles 31 to 38 and 41 to 49 (UE) may be calculated based on the time change (movement distance and movement time) of the position information in the movement history information recorded in each UE of the vehicle.

The frequency of transmission of vehicle information from the UEs of the vehicles 31-38 and 41-49 to the server 10 may be changed according to the occurrence of dangerous events on the road 90 (for example, past occurrence probability, time zone, area). For example, the transmission frequency of vehicle information may be set lower on roads where the probability of occurrence of dangerous events is low, and the frequency of transmission of vehicle information may be set higher than normal on roads where the probability of occurrence of dangerous events is high. In addition, the frequency of transmission of vehicle information may be set lower in time zones or areas in which the frequency of occurrence of dangerous events is low, and the frequency of transmission of vehicle information may be set higher than in normal times in time zones or areas in which the frequency of occurrence of dangerous events is high.

Further, some of the communication devices of the vehicles 31-38 and 41-49 have a function of direct communication (inter-vehicle communication) with other vehicles in the vicinity. For example, among the plurality of vehicles 31 to 38 traveling on the lane 91 in FIG. 1, vehicles 31 and 33 to 38 have direct communication (vehicle-to-vehicle communication) functions, and vehicle 32 does not have direct communication (vehicle-to-vehicle communication) functions.

Vehicle-to-vehicle communication uses radio waves such as microwaves and millimeter waves, for example. The frequency of inter-vehicle communication may be, for example, several hundred MHz lower than 1 GHz or a high frequency band of 1 GHz or higher. In addition, the frequency of inter-vehicle communication is 700 MHz band (715 MHz to 725 MHz), 5.8 GHz band (5770 MHz to 5850 MHz) and LTE-V2X Sidel used in ITS (Intelligent Transport Systems) and CACC (Cooperative Adaptive Cruise Control). It may be the 5.9 GHz band (5850 MHz to 5925 MHz) used in ink (PC-5). A plurality of antennas having predetermined beam widths may also be provided for vehicle-to-vehicle communication. For example, the vehicles 31, 33-38 may include a directional antenna for vehicle-to-vehicle communication with a vehicle in front, a directional antenna for vehicle-to-vehicle communication with a rear vehicle, a directional antenna for vehicle-to-vehicle communication with a vehicle on the right side, and a directional antenna for vehicle-to-vehicle communication with a vehicle on the left side.

The information distribution system also includes a map server 11 that manages map information including road-related information such as the position, shape, width W of the road 90, lanes 91 and 92, signal installation position, crosswalk position, presence/absence of a median strip, and presence/absence of roadside guardrails. Although the map server 11 is provided in the mobile communication network 15 in the example of FIG. Also, the map server 11 may be integrated with the server 10 .

In FIG. 1, for example, when a plurality of vehicles 31 to 38 are traveling on one lane 91 of a road 90 to the right in the figure, and the leading vehicle 31 detects a dangerous event, there is a case where it is desired to promptly distribute and notify the following vehicles 32 to 38 of the information on the dangerous event. As a method for notifying dangerous event information, an information distribution method in which direct communication (vehicle-to-vehicle communication) is used to relay dangerous event information from the leading vehicle 31 to the following vehicles 32 to 38, and an information distribution method in which the dangerous event information uploaded from the leading vehicle 31 is transmitted to the following vehicles 32 to 38 using a cellular network.

However, in the information distribution method using direct communication (vehicle-to-vehicle communication), all vehicles in the information relay range must have a direct communication (vehicle-to-vehicle communication) function, and if there is no relay destination vehicle within the range where direct communication (vehicle-to-vehicle communication) is possible, information relay will be interrupted.

Information distribution methods using the cellular network include a broadcast communication method and a unicast communication method. The broadcast communication method is a method of simultaneously transmitting and distributing information to all UEs existing in a cell of a certain base station. With this method, it is necessary to secure a radio band in advance regardless of whether broadcasting is performed or not, and as a result, the radio band that can be assigned to unicast communication is reduced. On the other hand, the unicast communication scheme is a scheme in which a radio band is secured only when necessary and individual communication is performed with each of a plurality of UEs. In this method, the number of UEs that can communicate per unit time is limited, and if information is to be distributed to UEs of many vehicles in a short time (for example, 1 to 2 seconds) by unicast communication, the downlink traffic from the base station 16 may increase rapidly in a short time and affect other general user UEs.

Therefore, in this embodiment, dangerous event information is distributed using a hybrid information distribution method that combines unicast communication and broadcast communication so that the dangerous event information can be quickly distributed to a plurality of vehicles 32 moving in the distribution area A behind the leading vehicle 31 that has detected the dangerous event, while suppressing the rapid increase in downlink traffic from the base station 16.

FIG. 2 is a block diagram showing an example of main functions of the server 10 according to this embodiment. In FIG. 2 , the server 10 includes an information transmission section 100 , a storage section 110 and an information distribution control section 120 . The information transmitting unit 100 is controlled by the control unit 125 to be described later, and can unicast transmit dangerous event information to vehicles targeted for unicast transmission via the base station 16 .

The storage unit 110 stores map information including road information such as the position, shape, width W of the road 90, lanes 91 and 92, intersections, signal installation positions, crosswalk positions, and other data necessary for dangerous event information distribution control. The map information stored in the storage unit 110 can be obtained from the map server 11 .

Information distribution control unit 120 includes dangerous event information reception unit 121 , vehicle information acquisition unit 122 as a mobile object information acquisition unit, distribution area determination unit 123 , transmission target determination unit 124 , and control unit 125 . The vehicle information may include information on the output of at least one of a gyroscope, an acceleration sensor, a speed sensor, and a magnetic sensor provided in the vehicle.

The dangerous event information receiving unit 121 receives dangerous event information via the base station 16 from the vehicle 31 that has detected a dangerous event occurring in an area where a plurality of vehicles are moving.

The vehicle information acquisition unit 122 receives and acquires vehicle information including the current position and moving speed of one or more vehicles traveling on the road 90 via the base station 16 . The vehicle information may include information regarding the presence or absence of a direct wireless communication (inter-vehicle communication) function between vehicles.

The distribution area determining unit 123 determines a distribution area A in which a plurality of vehicles 32 to 38 to which the dangerous event information received from the vehicle 31 is to be distributed are located. The distribution area A is, for example, an area on the upstream side in the vehicle movement direction (for example, an area up to a predetermined distance behind the vehicle 31) from the position where the dangerous event occurred.

A transmission target determination unit 124 selects and determines vehicles 32, 34, and 38 for unicast transmission via a mobile communication base station 16 based on position information of a plurality of vehicles 32 to 38 located within the distribution area A. Vehicles targeted for unicast transmission include, for example, at least one of a vehicle 32 in which no other vehicle capable of direct wireless communication (vehicle-to-vehicle communication) is located nearby, and a vehicle that does not have a direct wireless communication (vehicle-to-vehicle communication) function. At least one of the communicable distance and communication power of direct wireless communication (vehicle-to-vehicle communication), the spatial density of a plurality of vehicles, and the time zone may be used to determine the vehicle for unicast transmission.

The control unit 125 controls the information transmitting unit 100 so as to unicast the dangerous event information to the vehicles 32 , 34 , 38 that are the targets of unicast transmission via the base station 16 . The information to be transmitted to the vehicles 32, 34, 38 subject to unicast transmission may include forwarding necessity information indicating whether or not to perform forwarding by broadcast transmission of dangerous event information to vehicles in the surrounding area of the vehicle. Moreover, the dangerous event information may include at least one of time stamp information, which is information on the time when the dangerous event occurred, and information capable of identifying whether or not to output the dangerous event distribution information.

FIG. 3 is a block diagram showing an example of main functions of the communication device 300 of the vehicles 31-38, 41-49 according to this embodiment. In FIG. 3 , the communication device 300 includes a first wireless communication unit 310 , a second wireless communication unit 320 , an information processing control unit 330 and a dangerous event detection unit 350 .

The first wireless communication unit 310 can perform cellular network communication to communicate with the server 10 via the mobile communication base station 16 .
The second wireless communication unit 320 is capable of performing at least one of direct wireless communication with nearby vehicles and direct wireless communication with a roadside communication relay device (hereinafter referred to as “RSU (Road Side Unit)”) provided around the road 90.

The information processing control unit 330 receives, from the server 10, dangerous event information, which is distributed information, and forwarding necessity information indicating whether or not to perform broadcast transmission of the dangerous event information to nearby vehicles by direct wireless communication (vehicle-to-vehicle communication). can be controlled to prevent

Further, the information processing control unit 330 receives the first distribution information (dangerous event information) transmitted from the server 10 by the first wireless communication unit 310, receives the second distribution information (dangerous event information) transferred from the surrounding vehicle by the second wireless communication unit 320, compares the first distribution information and the second distribution information, and stores the first distribution information and the second distribution information in the storage unit 340 when the comparison result is inconsistent, and when the comparison result is in agreement, the first distribution information and the second distribution information are stored in the storage unit 340. Control may be performed such that one of the second distribution information is discarded and the other is stored in the storage unit 340 .

Further, the information processing control unit 330 receives distribution information (dangerous event information) transmitted from the server 10 by the first wireless communication unit 310, receives distribution information (dangerous event information) transferred from the RSU by the second wireless communication unit 320, compares the distribution information (dangerous event information) received from the server 10 and the distribution information (dangerous event information) received from the RSU, stores the two pieces of distribution information in the storage unit when the two pieces of distribution information do not match, and stores the two pieces of distribution information in the storage unit. If there is a match, one of the two pieces of distribution information may be discarded and the other may be stored.

The dangerous event detection unit 350 is configured using, for example, a camera as imaging means and an image processing unit that determines the occurrence of a dangerous event based on the image captured by the camera, and detects a dangerous event that has occurred around the vehicle. The dangerous event detection unit 350 may be configured by an operation input unit that is operated by the driver who has noticed the occurrence of a dangerous event to input information on the occurrence of the dangerous event.

FIG. 4 is a sequence diagram showing an example of dangerous event information delivery processing according to the present embodiment. FIG. 4 shows an example in which the leading vehicle 31 traveling in one lane 91 of the road 90 in FIG. 1 detects a dangerous event.
In FIG. 4, the server 10 receives from the map server 11 map information including road information such as the position, shape and width W of the road 90, lanes 91 and 92, intersections, signal installation positions, crosswalk positions, presence/absence of median strips, and presence/absence of roadside guardrails for the area to be managed (S101). Further, the server 10 regularly or irregularly receives vehicle information at a predetermined frequency for a plurality of vehicles including the vehicles 31 to 38 and 41 to 49 traveling on the road 90 to be managed (S102).

Next, when the vehicle 31 detects a dangerous event, it transmits information on the dangerous event to the server 10 via the base station 16 (S103, S104).

Next, when receiving the dangerous event information from the vehicle 31, the server 10 determines a distribution area A for distributing the dangerous event information based on the contents of the dangerous event and the position information of the vehicle traveling on the road 90 (S105). Further, the server 10 selects and determines the vehicles 32, 34, 38 for unicast transmission via the mobile communication base station 16 based on the position information of the plurality of vehicles 32 to 38 located within the distribution area A (S106).

Next, the server 10 unicasts the dangerous event information to the vehicles 32, 34, 38 that are the targets of unicast transmission via the base station 16 (S107).
The vehicle 32 does not transfer dangerous event information because there are no other vehicles in the vehicle-to-vehicle communication range. The server 10 may add transfer necessity information in unicast communication to the vehicle 32, and the vehicle 32 may not transfer dangerous event information based on the information.
Since there are other vehicles 33 and 35 in the vehicle-to-vehicle communication range B, the vehicle 34 transfers the dangerous event information to the vehicles 33 and 35 by broadcasting the vehicle-to-vehicle communication (S108). The server 10 may add transfer necessity information during unicast communication to the vehicles 33 and 35, and the vehicles 33 and 35 may transfer the dangerous event information by broadcasting inter-vehicle communication based on the information.
The dangerous event information from the vehicle 34 is also received by the vehicles 43 and 45 running on the next lane 92, but the vehicles 43 and 45 may discard the dangerous event information without outputting it because the information is not distributed to their own vehicles.
Since there are other vehicles 36 and 37 in the vehicle-to-vehicle communication range B, the vehicle 38 transfers the dangerous event information to the vehicles 36 and 37 by broadcasting the vehicle-to-vehicle communication (S109). The server 10 may add transfer necessity information during unicast communication to the vehicles 36 and 37, and the vehicles 36 and 37 may transfer the dangerous event information by broadcasting inter-vehicle communication based on the information.

The dangerous event information received by each of the vehicles 32 to 38 is displayed as image information on the display section, or output as sound information from an audio output section such as a speaker to notify the driver. Dangerous event information may be input to the drive control unit of each vehicle and used for vehicle control.

FIG. 5 is an explanatory diagram showing another example of the overall configuration of the information distribution system according to this embodiment. In addition, in FIG. 5, the same reference numerals are given to the same parts as those in FIG. 1, and the description thereof will be omitted. In the information distribution system of FIG. 5, when there is an RSU 17 capable of direct wireless communication in the distribution area A, the RSU 17 broadcasts dangerous event information to some vehicles in the distribution area A. In the example of FIG. 5, since four vehicles 35 to 38 are present within the direct wireless communication range C of the RSU 17, the RSU 17 broadcasts dangerous event information to the vehicles 35 to 38. FIG.

Since the vehicle 35 receives the dangerous event information transferred from the RSU 17 and the dangerous event information transferred from the vehicle 34, when both pieces of dangerous event information overlap, one of the pieces of dangerous event information may be discarded and the other piece of dangerous event information may be stored and output.

FIG. 6 is a sequence diagram showing another example of dangerous event information delivery processing according to the present embodiment. FIG. 6 is an example of using the RSU 17 of FIG. In FIG. 6, the description of the parts common to FIG. 4 is omitted.
In FIG. 6, after determining the distribution area A (S205), the server 10 selects and determines the vehicles 32, 34 and the RSU 17 for unicast transmission via the mobile communication base station 16 based on the position information of the plurality of vehicles 32 to 38 located in the distribution area A and the information of the surrounding RSUs 17 (S206).

Next, the server 10 unicasts the dangerous event information to the vehicles 32, 34 and the RSU 17, which are the targets of unicast transmission, via the base station 16 (S207, S208).
The vehicle 32 does not transfer dangerous event information because there are no other vehicles in the vehicle-to-vehicle communication range.
Since there are other vehicles 33 and 35 in the vehicle-to-vehicle communication range B, the vehicle 34 transfers the dangerous event information to the vehicles 33 and 35 by broadcasting the vehicle-to-vehicle communication (S209). The server 10 may add transfer necessity information during unicast communication to the vehicles 33 and 35, and the vehicles 33 and 35 may transfer the dangerous event information by broadcasting inter-vehicle communication based on the information.
Since the vehicles 36, 37, 38 are present in the surrounding range C where direct wireless communication is possible, the RSU 17 transfers the dangerous event information to the vehicles 36, 37, 38 by direct wireless communication broadcast transmission (S210).

5 and 6, since the dangerous event information transmitted from the RSU 17 also reaches the vehicle 35, the vehicle 35 compares the dangerous event information received from the RSU 17 and the dangerous event information received from the vehicle 34 to check whether or not they overlap (S211). If both pieces of dangerous event information overlap, one piece of dangerous event information is discarded (S212), and the other piece of dangerous event information is stored and output.

FIG. 7 is a block diagram showing another example of main functions of the server 10 according to this embodiment. FIG. 7 shows an example further provided with a distribution method selection unit 126 for selecting a distribution method for distributing dangerous event information. In addition, in FIG. 7, the same reference numerals are given to the same parts as in FIG. 2 described above, and the description thereof is omitted.

In FIG. 7, a distribution method selection unit 126 selects a distribution method to be used when distributing dangerous event information to each of the plurality of vehicles 32 to 38 located within the distribution area A from among a plurality of types of distribution methods including at least wireless communication via a mobile communication base station 16, based on at least one of the content of the dangerous event information to be distributed and the positional information of the plurality of vehicles located within the distribution area A. For example, the multiple types of distribution methods to be selected by the distribution method selection unit 126 include a first distribution method for distributing information by hybrid transmission combining unicast transmission from the base station 16 and broadcast transmission from the vehicle or RSU shown in FIGS. The distribution method selection unit 126, for example, selects a distribution method from the first distribution method and the second distribution method according to the urgency of the dangerous event detected by the vehicle 31, and distributes the dangerous event information to the vehicles 32 to 38 existing in the distribution area A.

FIG. 9 is a sequence diagram showing still another example of dangerous event information distribution processing according to the present embodiment. FIG. 9 shows an example in which dangerous event information is distributed by selecting the first distribution method or the second distribution method according to the content of the dangerous event detected by the leading vehicle 31 traveling in one lane 91 of the road 90 in FIG. In FIG. 9, the description of the parts common to FIG. 4 is omitted.
In FIG. 9, after determining the distribution area A (S305), the server 10 selects the first distribution method (hybrid transmission method) or the second distribution method (unicast transmission method) based on the details of the dangerous event detected by the vehicle 31 (S308).

For example, if the dangerous event detected by the vehicle 31 is a highly urgent dangerous event, the server 10 selects the second distribution method (unicast transmission method) described above, determines all the vehicles 32 to 38 existing in the distribution area A as unicast transmission targets (S307), and unicasts the dangerous event information to all the vehicles 32 to 38 via the base station 16 as shown in FIG. 8 (S308).

On the other hand, if the dangerous event detected by the vehicle 31 is a less urgent dangerous event, the server 10 selects the first distribution method (hybrid transmission method) described above, determines the vehicles 32, 34, and 38 among the vehicles 32 to 38 existing in the distribution area A as targets of unicast transmission (S309), and unicasts the dangerous event information to the vehicles 32, 34, and 38 via the base station 16 as shown in FIG. 1 (S310). ).

As described above, according to the present embodiment, as shown in FIGS. 1 to 4, dangerous event information is unicast only to some vehicles 32, 34, and 38 selected from a plurality of vehicles (moving bodies) 32 to 38 existing in the distribution area A to which the dangerous event information is to be distributed. This makes it possible to suppress a sharp increase in downlink traffic from the base station 16 compared to the case of unicast transmission to all of the vehicles 32 to 38. Moreover, the remaining vehicles 33, 35 to 37 within the distribution area A can transfer and distribute the dangerous event information from the vehicles 34, 38 by broadcasting through inter-vehicle communication (direct wireless communication). Therefore, the dangerous event information detected by the vehicle 31 can be distributed to all of the plurality of vehicles 32 moving in the distribution area A to be distributed via the base station 16 while suppressing the rapid increase of downlink traffic from the base station 16 of mobile communication.

Further, according to the present embodiment, by unicasting dangerous event information through the base station 16 only to some vehicles 32 and 34 selected from a plurality of vehicles (mobile bodies) 32 to 38 existing in the distribution area A to which the dangerous event information is to be distributed and to the RSU (roadside communication relay unit) 17, it is possible to suppress a sharp increase in downlink traffic from the base station 16 compared to the case of unicast transmission to all the vehicles 32 to 38. Moreover, the remaining vehicles 33, 35 to 38 in the distribution area A can transfer and distribute the dangerous event information from the vehicle 34 and the RSU 17 by direct radio communication broadcast transmission. Therefore, the dangerous event information detected by the vehicle 31 can be distributed to all of the plurality of vehicles 32 moving in the distribution area A to be distributed via the base station 16 while suppressing the rapid increase of downlink traffic from the base station 16 of mobile communication.

Further, according to this embodiment, as shown in FIGS. 7 to 9, it is possible to select an appropriate distribution method according to the urgency of the dangerous event detected by the vehicle 31, and distribute the dangerous event information via the base station 16 to all of the plurality of vehicles 32 moving in the distribution area A to be distributed.

Further, according to the present embodiment, dangerous event information to be transmitted to a vehicle (moving body) targeted for unicast transmission includes forwarding necessity information indicating whether or not to perform forwarding by broadcast transmission of information to surrounding vehicles. This makes it possible to avoid forwarding processing by unnecessary broadcast transmission based on the forwarding necessity information, thereby reducing the load of communication, control, etc. on the vehicle.

In addition, according to the present embodiment, the vehicles (moving bodies) targeted for unicast transmission include at least one of a vehicle in which other vehicles capable of direct wireless communication are not located nearby and a vehicle that does not have a direct wireless communication (vehicle-to-vehicle communication) function.

Further, according to the present embodiment, at least one of the communicable distance and communication power of direct wireless communication (vehicle-to-vehicle communication), the spatial density of vehicles, and the time zone is used to determine the vehicle (mobile body) to be unicast-transmitted. By doing so, it is possible to reduce the number of vehicles that have failed to deliver dangerous event information by broadcast transmission from vehicles after unicast transmission.

Further, according to the present embodiment, dangerous event information distributed to a plurality of vehicles (moving bodies) 32 to 38 has at least one of time stamp information and information capable of identifying whether or not to output distribution information, so that control using time stamp information and output control of distribution information can be specified from the server 10 in a vehicle that receives dangerous event information.

It should be noted that the processing steps as well as the components of the mobile communication system described herein may be implemented by various means. For example, these processes and components may be implemented in hardware, firmware, software, or any combination thereof.

For hardware implementation, means such as processing units used to implement the above steps and components in an entity (e.g., various wireless communication devices, Node Bs, terminals, hard disk drives, or optical disk drives) may be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processors (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, electronic devices, etc. It may be implemented in a device, other electronic unit designed to perform the functions described herein, a computer, or a combination thereof.

Also, for firmware and/or software implementations, means such as processing units used to implement the above components may be implemented in programs (e.g., code such as procedures, functions, modules, instructions, etc.) that perform the functions described herein. In general, any computer/processor readable medium tangibly embodying firmware and/or software code may be used to implement means, such as a processing unit, used to implement the steps and components described herein. For example, firmware and/or software code may be stored in memory and executed by a computer or processor, such as in a controller. The memory may be implemented within the computer or processor, or external to the processor. The firmware and/or software code may also be stored in computer or processor readable media such as, for example, random access memory (RAM), read only memory (ROM), nonvolatile random access memory (NVRAM), programmable read only memory (PROM), electrically erasable PROM (EEPROM), FLASH memory, floppy disk, compact disk (CD), digital versatile disk (DVD), magnetic or optical data storage devices, and the like. The code may be executed by one or more computers or processors and may cause the computers or processors to perform certain aspects of the functionality described herein.

Also, the medium may be a non-temporary recording medium. Also, the code of the program may be readable and executable by a computer, processor, or other device or apparatus machine, and its format is not limited to a particular format. For example, the program code may be source code, object code or binary code, or may be a mixture of two or more of these codes.

Moreover, the description of the embodiments disclosed herein is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein are applicable to other variations without departing from the spirit or scope of this disclosure. This disclosure, therefore, is not to be limited to the examples and designs described herein, but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

10: Server 16: Base stations 31-38: Vehicles 41-49: Vehicle 90: Roads 91, 92: Lane 100: Information transmitting unit 110: Storage unit 120: Information distribution control unit 121: Danger event information reception unit 122: Vehicle information acquisition unit 123: Distribution area determination unit 124: Transmission target determination unit 125: Control unit 126: Distribution method selection unit 300 : communication device 310 : first wireless communication unit 320 : second wireless communication unit 330 : information processing control unit 340 : storage unit 350 : dangerous event detection unit

Claims (12)

A server that distributes information to a plurality of moving bodies,
a distribution area determination unit that determines a distribution area in which a plurality of mobile objects to which information is to be distributed are located;
a selection unit for selecting, based on the content of information to be distributed, a distribution method to be used when distributing the information to each of the plurality of mobile units located within the distribution area, from a plurality of types of distribution methods including at least wireless communication via a mobile communication base station;
an information distribution unit that distributes the information to the plurality of mobile units via the base station using the selected wireless distribution method;
A server characterized by comprising: A server that distributes information to a plurality of moving bodies,
a distribution area determination unit that determines a distribution area in which a plurality of mobile objects to which information is to be distributed are located;
a selection unit for selecting a distribution method to be used when distributing the information to each of the plurality of mobile units located within the distribution area from among a plurality of types of distribution methods including at least wireless communication via a mobile communication base station, based on at least one of the content of the information to be distributed and the location information of the plurality of mobile units located within the distribution area;
an information distribution unit that distributes the information to the plurality of mobile units via the base station using the selected wireless distribution method;
The plurality of types of delivery methods are
a first distribution method for selecting and determining a mobile object for unicast transmission via a mobile communication base station based on position information of the plurality of mobile objects located within the distribution area, and unicast transmitting the information to the mobile object for unicast transmission via the mobile communication base station;
and a second distribution method for unicasting the information to each of the plurality of mobile units located within the distribution area via the base station. In the server of claim 2,
The server, wherein the information received by the mobile object of unicast transmission is broadcast-transmitted by direct wireless communication to other mobile objects located in the vicinity of the mobile object of unicast transmission. In the server of claim 3,
The server, wherein the information to be transmitted to the unicast transmission target mobile includes transfer necessity information indicating whether or not to transfer the information by broadcast transmission to the surrounding mobiles. In the server according to any one of claims 2 to 4,
A server characterized in that the mobiles targeted for unicast transmission include at least one of mobiles in which other mobiles capable of direct wireless communication are not located in the vicinity, and mobiles that do not have a direct wireless communication function between mobiles. In the server according to any one of claims 2 to 5,
Unicast transmission targets from the server via the base station include roadside communication relay devices provided around a moving route of the distribution area,
A server that selects and determines the mobile units to be subjected to unicast transmission based on the location information of the plurality of mobile units located within the distribution area and the location information of the roadside communication relay device. In the server according to any one of claims 2 to 6,
A server using at least one of a communicable distance and communication power of direct wireless communication between mobiles, a spatial density of the plurality of mobiles, and a time zone to determine the mobiles to be unicast-transmitted. In the server according to any one of claims 1 to 7,
The server, wherein the information distributed to the plurality of mobile units has at least one of time stamp information and information capable of identifying necessity of outputting the distribution information. In the server according to any one of claims 1 to 8,
an information acquisition unit that receives and acquires information on the position and speed of the mobile object and whether there is a direct wireless communication function between the mobile objects from the plurality of mobile objects via the base station;
an information storage unit that stores position information of each of the plurality of moving bodies;
A server characterized by comprising : In the server according to any one of claims 1 to 9 ,
a dangerous event information receiving unit that receives information on the dangerous event from the moving object that has detected a dangerous event that has occurred in an area in which the plurality of moving objects are moving;
the information to be distributed is information on the dangerous event;
The server, wherein the distribution area is an area on the upstream side in the moving direction of the moving body from the position where the dangerous event occurs. A communication system comprising the server according to any one of claims 1 to 10 and a base station for mobile communication,
The communication system is
further comprising a roadside communication relay device provided around the moving route of the mobile body and capable of unicast transmission of information from the server via the base station;
A communication system, wherein the information received by the roadside communication relay device is broadcast-transmitted by direct wireless communication to mobile units located around the roadside communication relay device . A communication method for distributing information to a plurality of mobile bodies,
Determining a distribution area in which a plurality of mobiles to which information is to be distributed are located;
selecting a distribution method used when distributing the information to each of the plurality of mobile units located within the distribution area from a plurality of types of distribution methods including at least wireless communication via a mobile communication base station, based on the content of the information to be distributed;
distributing the information to the plurality of mobiles via the base station using the selected wireless distribution method;
A communication method comprising :

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