JP4586676B2 - On-vehicle wireless communication device and wireless communication system - Google Patents

Description

  The present invention relates to an in-vehicle wireless communication apparatus and a wireless communication system that transmit transmission information by relaying with a wireless communication apparatus mounted on another vehicle.

  With the development of wireless communication technology, it is possible to communicate between traveling vehicles, and the development of inter-vehicle communication is being promoted. In vehicle-to-vehicle communication, in order to improve safety by recognizing the positional relationship with other vehicles, the vehicle information (current position, vehicle speed, etc.) is transmitted to other vehicles in the vicinity. The radio wave used for inter-vehicle communication is a high frequency in the gigahertz band, has high straightness, and has a large diffraction loss. For this reason, in vehicle-to-vehicle communication, an area where direct communication is possible is limited at intersections where roads intersect, and therefore, data relay that relays information by using a wireless communication device mounted on another vehicle is effective.

As a method of relaying data at an intersection, for example, select each other vehicle (vehicle equipped with a wireless communication device) that is the farthest within the reach of radio waves from the host vehicle on each branch road that connects to the intersection. Then, a relay request is made to other vehicles. And the own vehicle information relay-requested by the relay vehicle of each branch road is broadcast, and the own vehicle information is transmitted to other vehicles existing on each branch road outside the reach of radio waves from the own vehicle (Patent Document) 1). For example, in the case of an intersection where two roads are orthogonal to each other, there are three branch roads in addition to the road on which the host vehicle is traveling. Therefore, relay vehicles are selected on the three branch roads, respectively. Such data relay is performed in each vehicle capable of vehicle-to-vehicle communication, each vehicle selects a relay vehicle, and each relay vehicle broadcasts information requested to be relayed.
JP 2005-12522 A

  If there is no vehicle that can be relayed on each branch road, it must be relayed to a branch road that does not have a relayable vehicle by radio waves broadcast from the relay vehicle on the branch road where the relayable vehicle exists. Don't be. For example, when a branch road where a relayable vehicle exists and a branch road where there is no relayable vehicle are orthogonal to each other, the farther the position of the vehicle selected as the relay vehicle is from the center of the intersection, the more The diffraction loss of radio waves to the orthogonal branch road side increases, and the communicable distance (area) to the orthogonal branch road side decreases, making it impossible to transmit information. At this time, if the output of radio waves is increased in order to increase the communicable distance, power consumption increases.

  Further, in each vehicle capable of inter-vehicle communication, a relay request is always made to surrounding vehicles, so that communication traffic increases in accordance with an increase in traffic volume near an intersection. Furthermore, since each vehicle selects a relay vehicle according to the number of branch roads and broadcasts on each of the plurality of relay vehicles, communication traffic in the vicinity of the intersection increases.

  Then, this invention makes it a subject to provide the vehicle-mounted radio | wireless communication apparatus and radio | wireless communications system which can perform vehicle-to-vehicle communication efficiently.

An in-vehicle wireless communication apparatus according to the present invention is an in-vehicle wireless communication apparatus that relays transmission information through a wireless communication apparatus mounted on another vehicle, and determines that the own vehicle is approaching an intersection and a plurality of other When the position information transmitted from the wireless communication device of the vehicle is received, the radio wave transmitted from the wireless communication device of the own vehicle within the range including the intersection arrives based on the position information of the plurality of other vehicles If it is determined that there are a plurality of wireless communication devices installed in other vehicles near the intersection center that is the range to be selected, the wireless communication device installed in the other vehicle located closest to the center of the intersection is selected as the relay wireless communication device. The transmission information is transmitted to the specified relay wireless communication apparatus.

  In this in-vehicle wireless communication device, when a vehicle approaches an intersection, the wireless communication device of another vehicle existing near the intersection center is designated as a relay wireless communication device (that is, a vehicle capable of wireless communication near the intersection center is designated as a relay vehicle. specify). In the wireless communication device, in order to relay (transfer) information by the designated relay wireless communication device, transmission information (for example, the current position of the host vehicle, vehicle speed, brake information, Send turn signal information). As described above, since the relay wireless communication device relays from the vicinity of the intersection center, the radio wave (relayed signal) from the relay wireless communication device is not diffracted or diffraction loss is suppressed as much as possible on all roads connected to the intersection. The communication distance becomes longer (the communication area becomes wider). Therefore, information can be reliably transmitted to vehicles around the intersection with low power (without increasing the output of radio waves). Further, since relaying at the intersection is possible with one relay wireless communication device, communication traffic at the intersection can be suppressed. Therefore, with this in-vehicle wireless communication device, efficient vehicle-to-vehicle communication can be performed at the intersection, and information can be reliably transmitted to surrounding vehicles at the intersection. In addition, since information on surrounding vehicles at the intersection can be acquired, each vehicle can safely drive its own vehicle with respect to other vehicles, and safety within the intersection can be improved.

  In this in-vehicle wireless communication device, when there are a plurality of wireless communication devices mounted on other vehicles near the intersection center, the wireless communication device mounted on the other vehicle closest to the intersection center is selected as the relay wireless communication device (that is, When there are a plurality of vehicles capable of wireless communication near the intersection center, the vehicle closest to the intersection center is selected as a relay vehicle). As the relay position is closer to the intersection center, the diffraction loss can be reduced, and an equally efficient relay can be performed on all roads connected to the intersection.

  The on-vehicle wireless communication device of the present invention may be configured to stop transmission of transmission information when the transmitted transmission information is received from the relay wireless communication device.

  In this in-vehicle wireless communication device, when the transmission information transmitted to the relay wireless communication device for relaying is received, relaying (transfer) by the relay wireless communication device is normally performed. Stop sending transmission information. As described above, when it is confirmed that the relay wireless communication apparatus has normally relayed, the relay of the transmission information is stopped, and unnecessary communication is eliminated to reduce communication traffic.

The wireless communication system according to the present invention is a wireless communication system in which transmission information is relayed by a vehicle-mounted wireless communication device. In the first vehicle-mounted wireless communication device, the first vehicle-mounted wireless communication device is mounted. When it is determined that the host vehicle is approaching the intersection and the position information transmitted from the wireless communication devices of the plurality of other vehicles can be received, the intersection is included based on the position information of the plurality of other vehicles. If it is determined that there are multiple wireless communication devices installed in other vehicles in the vicinity of the intersection center where the radio waves transmitted from the wireless communication device of the own vehicle reach the range, it exists at the position closest to the center of the intersection specified by selecting a wireless communication device mounted in the other vehicle as a relay radio communication device transmits the transmission information to the relay radio communication apparatus such designation, the second vehicle radio communication device, the first vehicle If it is determined that specified in the relay radio communication devices by the line communication apparatus, and transmits and relays the information transmitted from the first vehicle wireless communication device.

  In this wireless communication system, the first in-vehicle wireless communication device designates the wireless communication device of another vehicle existing near the center of the intersection as the relay wireless communication device in the same manner as the above-described in-vehicle wireless communication device. Transmission information is transmitted to the relay wireless communication apparatus. In the second vehicle-mounted wireless communication device, when it is determined that the first vehicle-mounted wireless communication device is designated as the relay wireless communication device, the transmission information from the first vehicle-mounted wireless communication device is relayed and transmitted. Yes (forward). This wireless communication system also has the same effect as the above-described in-vehicle wireless communication device.

  The first in-vehicle wireless communication device of the wireless communication system of the present invention may be configured to stop transmission of transmission information when the transmitted transmission information is received from the relay wireless communication device. This wireless communication system has the same effects as the above-described on-vehicle wireless communication devices.

  According to the present invention, efficient vehicle-to-vehicle communication can be performed around an intersection.

  Embodiments of an in-vehicle wireless communication apparatus and a wireless communication system according to the present invention will be described below with reference to the drawings.

  In the present embodiment, the present invention is applied to a wireless communication system in which a similar wireless communication device is mounted on each vehicle and performs inter-vehicle communication. In the inter-vehicle communication according to the present embodiment, in order to improve safety by grasping the positional relationship with other vehicles, each vehicle transmits various information (data) of the own vehicle and Receive information. The vehicle information includes current position, vehicle speed, traveling direction, various vehicle information (for example, brake information, accelerator information, turn signal information, shift position information) and the like.

  The wireless communication system 1 will be described with reference to FIGS. FIG. 1 is a configuration diagram of a wireless communication apparatus according to the present embodiment. FIG. 2 is an example of the positional relationship between the host vehicle and the surrounding vehicles when requesting relaying in inter-vehicle communication at an intersection. FIG. 3 is an example of the positional relationship between the own vehicle that is relaying data and a new surrounding vehicle in inter-vehicle communication at an intersection.

  In the wireless communication system 1, vehicle-to-vehicle communication is performed between the vehicles 2, 3A, 3B,. In the wireless communication system 1, each wireless communication device 10 of each vehicle 2, 3A, 3B,... Performs the same processing and broadcasts the data of the own vehicle at regular intervals. In the wireless communication system 1, signals are usually transmitted and received directly between vehicles. When a vehicle enters an intersection (a place where two or more roads intersect), the signal closest to the intersection center is also relayed as a relay vehicle. Send and receive. Each vehicle 2, 3A, 3B,... That performs inter-vehicle communication in the wireless communication system 1 is assigned a vehicle identification ID in order to identify each vehicle. Note that the relay process may always be performed not only when entering the intersection.

  In the vicinity of the intersection, it is possible to visually confirm other vehicles on the running road, but other vehicles running on the road that intersects the running road may not be visible until entering the intersection. is there. Therefore, in order to travel safely at an intersection, the current position of the other vehicle traveling on the road intersecting the traveling road is obtained, and the current vehicle's current position is also obtained from the other vehicle traveling on the intersecting road. It is important to communicate the location. However, at the intersection, there is a predetermined angle (for example, 90 °) between the traveling road and the road that intersects, so that radio waves are attenuated by diffraction loss, and the communication distance is shortened. Therefore, at the intersection, the communication area between the vehicles existing on the intersecting roads is narrow, and data cannot be acquired between the vehicles existing at a position slightly away from the intersection. Therefore, in the wireless communication system 1, another vehicle closest to the center of the intersection is used, and data is transmitted to each road connected to the intersection by relay using the other vehicle as a relay vehicle. At this time, the closer the relay vehicle is to the intersection center, the more radio waves can be propagated without diffraction or the diffraction loss is suppressed as much as possible on all roads connected to the intersection, and the communication area becomes wider.

  The wireless communication device 10 will be described. The wireless communication device 10 is a wireless communication device capable of bidirectional communication using a gigahertz band, and performs wireless communication between vehicles by a CSMA [Carrier Sense Multiple Access] method. The CSMA method is a method in which a radio communication apparatus transmits a signal after confirming a vacancy (idle) for a predetermined time or more in a communication path. The wireless communication device 10 transmits data of the own vehicle and receives data of other vehicles around the own vehicle at regular time intervals. When the wireless communication device 10 approaches the intersection, the wireless communication device 10 selects another vehicle at a position closest to the center of the intersection, requests other vehicles to relay, and transmits data by relay. For this purpose, the wireless communication device 10 includes an antenna 11, a transmission / reception unit 12, a transmission control unit 13, a reception control unit 14, and a data processing unit 15, and is connected to the navigation device 20.

  The wireless communication device 10 is connected to a vehicle computer (not shown) that executes various applications (for example, an anti-collision application at an intersection). The wireless communication device 10 transmits the received other vehicle data (current position, etc.) to the vehicle computer at regular time intervals. Further, in the wireless communication device 10, brake information (brake pedal ON / OFF), accelerator information (accelerator pedal ON / OFF), turn signal information (left turn, right turn, right) acquired by the vehicle computer at regular intervals. Shift position information is received as vehicle data. Note that these vehicle data may be directly acquired by connecting to sensors or switches for detecting these vehicle data.

  The navigation device 20 is a device that displays a current position of the host vehicle on a map and guides a route to a destination. Therefore, the navigation device 20 holds a map database and extracts map information around the current position. The navigation device 20 detects the current position and traveling direction of the vehicle using a GPS [Global Positioning System], a direction sensor, a vehicle speed sensor, and the like. Therefore, the wireless communication device 10 receives map information around the current position and data such as the current position, traveling direction, and vehicle speed from the navigation device 20 at regular intervals. The traveling direction and the vehicle speed may be directly acquired by connecting to a sensor that detects these.

  The antenna 11 is a transmission / reception antenna and transmits / receives various signals. The antenna 11 is an omnidirectional antenna, and receives signals from all directions and transmits signals in all directions. When transmitting, a transmission signal is sent from the transmission control unit 13 to the antenna 11 via the transmission / reception unit 12. When receiving, a reception signal is sent from the antenna 11 to the reception control unit 14 via the transmission / reception unit 12. The transmission control unit 13 performs various conversion processes on the transmission data from the data processing unit 15 to generate a transmission signal, and outputs the transmission signal to the transmission / reception unit 12. The reception control unit 14 performs various conversion processes on the received signal received by the antenna 11 to extract data, and outputs the data to the data processing unit 15.

  The data processing unit 15 includes a CPU [Central Processing Unit], a ROM [Read Only Memory], a RAM [Random Access Memory], and performs various processes such as a transmission data process, a reception data process, and a data relay process. The data processing unit 15 transmits and receives various data through communication with the navigation device 20 (particularly, a navigation computer) and a vehicle computer. The data processing unit 15 is connected to the transmission control unit 13 and the reception control unit 14, outputs transmission data to the transmission control unit 13, and inputs reception data from the reception control unit 14.

  Transmission data processing will be described. The data processing unit 15 adds the vehicle identification ID of the host vehicle to the vehicle information such as the current position from the navigation device 20, the vehicle speed, the traveling direction, and the brake information, accelerator information, turn signal information, and shift position information from the vehicle computer. Generated transmission data. Then, the data processing unit 15 outputs the transmission data to the transmission control unit 13 according to the transmission timing by the CSMA method.

  Reception data processing will be described. Each time reception data is input from the reception control unit 14, the data processing unit 15 extracts the current position, vehicle speed, traveling direction, and various vehicle information of other vehicles from the reception data and transmits them to the vehicle computer. At this time, the data processing unit 15 may perform the following processing. The data processing unit 15 identifies a range (road) in which the host vehicle will travel based on the current position, traveling direction, turn signal information, and map information around the current position of the host vehicle, and the other vehicle indicated in the received data. From the current position, the traveling direction, and the turn signal information, it is determined whether or not the vehicle exists within the range where the vehicle travels or may fall within the range. Then, in the data processing unit 15, when the other vehicle exists or may enter the range, the current position of the other vehicle, the vehicle speed, the traveling direction, and various vehicle information indicated in the received data To the vehicle computer.

  Data relay processing will be described. The data processing unit 15 determines whether or not the vehicle is approaching an intersection based on the current position and the traveling direction from the navigation device 20 and the map information around the current position. When data relay processing is always performed, it is not determined whether or not the vehicle is approaching an intersection.

  When it is determined that the vehicle is approaching the intersection, the data processing unit 15 indicates the received data every time reception data is input from the reception control unit 14 in order to acquire position data of other vehicles existing in the vicinity. The current position of the other vehicle and the vehicle identification ID are temporarily stored. It can be inferred that other vehicles that can receive data exist in the vicinity of the host vehicle. Further, the data processing unit 15 extracts the intersection information that enters from the map information around the current position, and sets the assumed area AS based on the intersection information (see FIG. 2). The assumed area AS is a range including an intersection and a range where radio waves transmitted from the wireless communication device 10 reach. Then, the data processing unit 15 determines whether or not the other vehicle exists in the assumed area AS based on the current position of the other vehicle for each temporarily stored data of the other vehicle. In the example shown in FIG. 2, there are other vehicles 3A, 3B, 3C, 3D around the host vehicle 2, and there are the other vehicles 3A and 3B in the assumed area AS.

  When there are other vehicles in the assumed area AS, the data processing unit 15 selects the other vehicle closest to the intersection center from among the plurality of other vehicles as a relay vehicle, and there is only one vehicle. When doing so, select other vehicles as relay vehicles. In the example shown in FIG. 2, there are two other vehicles 3A and 3B in the assumed area AS. However, since the other vehicle 3A is located closer to the center of the intersection, the other vehicle 3A is selected as the relay vehicle. The On the other hand, when there is no other vehicle in the assumed area AS, the data processing unit 15 again collects position data of other vehicles existing in the vicinity, and determines whether the collected other vehicle exists in the assumed area AS. To do.

  When the relay vehicle is selected, the data processing unit 15 uses the own vehicle information (current position, vehicle speed, traveling direction, various vehicle information) as relay request information for requesting relay of the own vehicle information, and the other vehicle selected as the relay vehicle. Transmission data to which transmission destination information including the vehicle identification ID and transmission source information including the vehicle identification ID of the host vehicle is added is generated, and the transmission data of the relay request is output to the transmission control unit 13.

  By the way, if this transmission data is received by the relay vehicle, the relay vehicle recognizes that the relay vehicle has been selected as the relay vehicle because the vehicle identification ID of the destination information matches its own vehicle identification ID, and the relay request. Broadcasts information about the host vehicle. On the other hand, when a vehicle other than the relay vehicle receives this transmission data, the transmission data of this relay request is discarded because the vehicle identification ID of the transmission destination information is different from its own vehicle identification ID.

  The data processing unit 15 monitors the reception data every time reception data is input from the reception control unit 14 for a certain period of time. In this monitoring, the data processing unit 15 determines whether the transmission destination is another vehicle selected as the relay vehicle from the vehicle identification ID included in the received data. When it is determined that the transmission data is from the relay vehicle, the data processing unit 15 determines whether or not the received data includes the own vehicle information requested for relay. When the own vehicle information is included, the data processing unit 15 determines that the data relay has been performed normally. On the other hand, when it is not possible to confirm that the data relay has been normally performed by monitoring for a certain period of time, the data processing unit 15 requests the relay vehicle to be relayed again by the same process as described above.

  In the data processing unit 15, after confirming that the data relay is normally performed, when a new other vehicle is detected in the vicinity by the relayed received data input from the reception control unit 14, the same processing as described above is performed again. Request relay to the selected relay vehicle. At this time, in the data processing unit 15, in the case where the vehicle identification ID of the transmission source included in the relayed reception data is a vehicle identification ID other than the vehicle identification ID of the surrounding vehicle temporarily stored, another vehicle is newly added in the vicinity. Judge that it appeared. The data processing unit 15 stops the data relay request when it is not possible to detect a new other vehicle after confirming that the data relay is normally performed.

  For example, when the state shown in FIG. 3 is reached after a short time from the state shown in FIG. 2, another vehicle 3E is approaching the intersection. In this case, in the other vehicle 3E as well as the own vehicle 2, the other vehicle 3A is used as a relay vehicle to make a data relay request. Therefore, the other vehicle 3A also broadcasts the own vehicle information of the other vehicle 3E requested to be relayed. Here, the own vehicle 2 can detect the new other vehicle 3E by receiving the received data including the own vehicle information of the other vehicle 3E relayed by the other vehicle 3A and the vehicle identification ID of the other vehicle 3E. it can. Then, the own vehicle 2 makes a data relay request to the other vehicle 3A again in order to transmit the own vehicle information to the other vehicle 3E.

  When the data processing unit 15 receives a relay request as received data (that is, when the host vehicle is selected as a relay vehicle and a data relay request is made), the data processing unit 15 includes the vehicle information to be relayed indicated in the received data The transmission data to which the relay vehicle information including the vehicle identification ID and the transmission source information including the vehicle identification ID of the vehicle that requested the relay are added is generated, and the transmission data is output to the transmission control unit 13. In the wireless communication device 10, the transmission control unit 13 converts the transmission data into a transmission signal, and broadcasts information on other vehicles from the antenna 11 via the transmission / reception unit 12.

  With reference to FIGS. 1-3, the operation | movement when the radio | wireless communication apparatus 10 mounted in the own vehicle 2 relays data by the other vehicle 3A is demonstrated. In particular, the processing in the data processing unit 15 will be described with reference to the flowchart of FIG. FIG. 4 is a flowchart of data relay processing in the data processing unit of the wireless communication apparatus of FIG.

  The antenna 11 receives various signals flying from all directions. This received signal is sent to the reception control unit 14 via the transmission / reception unit 12. The reception control unit 14 performs various conversion processes on the received signal to extract the received data, and outputs the received data to the data processing unit 15.

  The data processing unit 15 acquires brake information, accelerator information, turn signal information, shift position information, and the like from the vehicle computer at regular intervals. In addition, the data processing unit 15 acquires the current position, the traveling direction, the vehicle speed, and map information around the current position from the navigation device 20 at regular time intervals. Then, the data processing unit 15 determines whether or not the vehicle is approaching the intersection based on the current position, the traveling direction, and the map information.

  When it is determined that the vehicle is approaching the intersection, the data processing unit 15 acquires the current position and vehicle identification ID of other vehicles in the vicinity from the received data every time the received data is input, and temporarily stores them (S1). ). Then, the data processing unit 15 sets the assumed area AS from approaching intersection information, and determines whether or not a surrounding vehicle exists in the assumed area AS based on the temporarily stored current position (S2). . If it is determined in S2 that there is no surrounding vehicle, the data processing unit 15 returns to S1, acquires the current position of the surrounding vehicle again, and determines whether it exists in the assumed area AS.

  If it is determined in S2 that there is a surrounding vehicle, the data processing unit 15 selects the other vehicle 3A closest to the intersection center from among the surrounding vehicles 3A and 3B existing in the assumed area AS (S3). .

  When the relay vehicle 3A is selected, the data processing unit 15 causes the host vehicle information (current position, traveling direction, vehicle speed, various vehicle information), relay request information for requesting relay of the host vehicle information, and transmission destination information (relay vehicle information on the relay vehicle 3A). Transmission data including vehicle identification ID), transmission source information (vehicle identification ID of the host vehicle 2), and the like are generated, and this transmission data is output to the transmission control unit 13 (S4). The transmission control unit 13 converts this transmission data into a transmission signal. The transmission signal is transmitted from the antenna 11 via the transmission / reception unit 12.

  When the wireless communication device 10 of the other vehicle 3A selected as the relay vehicle receives this transmission signal, the wireless communication device 10 of the other vehicle converts the transmission signal into transmission data, and based on the information indicated in the transmission data Recognize that the relay is requested. And in this radio | wireless communication apparatus 10, the transmission data which consist of the own vehicle information shown by transmission data, relay vehicle information (vehicle identification ID of the other vehicle 3A), transmission origin information (vehicle identification ID of the own vehicle 2), etc. are produced | generated. Then, the transmission data is converted into a transmission signal and broadcast. The broadcast transmission signal propagates to all roads connected to the intersection from the vicinity of the intersection center with no diffraction or as much as possible. Therefore, this transmission signal reaches a vehicle some distance away from the intersection on each road.

  The data processing unit 15 monitors received data for a certain time (S5). Then, the data processing unit 15 determines whether or not data including the own vehicle information requested for relay from the other vehicle 3A requested for relay in this monitoring is received (S6). If it is determined that the data requested for relay in S6 has not been received, the data processing unit 15 returns to S4, requests the relay again, and performs monitoring.

  When it is determined that the data requested to be relayed is received in S6, the data processing unit 15 determines whether there is a new other vehicle in the vicinity based on the data relayed from the other vehicle (S7). When it is determined in S7 that there is a new other vehicle 3E, the data processing unit 15 returns to S4 and requests data relay again to transmit the own vehicle information to the other vehicle 3E. On the other hand, when it is determined in S7 that there is no new other vehicle, the data processing unit 15 stops the data relay request (S8).

  According to this wireless communication system 1 (wireless communication apparatus 10), in vehicle-to-vehicle communication at an intersection, another vehicle closest to the center of the intersection is selected as a relay vehicle to relay data, so that diffraction is performed on all roads connected to the intersection. Relaying with no loss or as much suppression as possible is possible, and the communication area can be expanded and the power consumption can be suppressed. Moreover, since relay is performed by one relay vehicle, communication traffic can be suppressed.

  Further, according to the wireless communication system 1, since the relay is stopped when it is confirmed that the relay is normally performed, unnecessary broadcast from the relay vehicle is eliminated, and the communication traffic can be suppressed as much as possible. Further, according to the wireless communication system 1, when a new other vehicle approaching the intersection is detected, data relay is performed again, so that the information on the own vehicle is surely transmitted to the other vehicle entering the intersection. Can communicate.

  Thus, in the wireless communication system 1, highly efficient vehicle-to-vehicle communication is possible, and each piece of information on surrounding vehicles can be reliably shared at an intersection. By mutually acquiring information on surrounding vehicles at the intersection, each vehicle can safely drive its own vehicle relative to other vehicles, and safety within the intersection can be improved.

  As mentioned above, although embodiment which concerns on this invention was described, this invention is implemented in various forms, without being limited to the said embodiment.

  For example, in this embodiment, the present invention is applied to a wireless communication system that performs vehicle-to-vehicle communication, but may be applied to a wireless communication system that performs other communication such as road-to-vehicle communication in addition to vehicle-to-vehicle communication.

  In the present embodiment, various types of information such as map information and the current position are acquired from the navigation device. However, in the case of a device that does not include the navigation device, a current position detection such as a map database or GPS is detected in the wireless communication device. It is good also as a structure provided with a means.

  Further, in the present embodiment, the current position of the host vehicle, the vehicle speed, the traveling direction, various vehicle information, etc. are used as data to be transmitted / received in the inter-vehicle communication, but the data to be transmitted / received is not limited to these, Data may be used.

  In the present embodiment, the other vehicle closest to the center of the intersection is used as the relay vehicle. However, other vehicles near the center of the intersection such as other vehicles existing in the intersection may be relayed even if they are not closest to the center. It may be a vehicle.

  In the present embodiment, an assumed area is set and a relay vehicle is selected from the vehicles existing in the assumed area. However, a vehicle that is closest to the intersection center is directly selected without setting the assumed area. It is good.

  In the present embodiment, the data relay is stopped when the relay request data is received from the relay vehicle. However, the data relay may be continued until the vehicle enters the intersection or passes through the intersection.

  Further, in the present embodiment, the configuration is such that a new other vehicle approaching the intersection is detected, but this detection may not be performed.

It is a block diagram of the radio | wireless communication apparatus which concerns on this Embodiment. It is an example of the positional relationship of the own vehicle and the surrounding vehicle at the time of requesting a relay in inter-vehicle communication at an intersection. It is an example of the positional relationship between the own vehicle which is relaying data and a new surrounding vehicle in inter-vehicle communication at an intersection. 3 is a flowchart of data relay processing in a data processing unit of the wireless communication apparatus in FIG. 1.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Wireless communication system, 2 ... Own vehicle, 3A, 3B, 3C, 3D, 3E ... Other vehicle, 10 ... Wireless communication apparatus, 11 ... Antenna, 12 ... Transmission / reception part, 13 ... Transmission control part, 14 ... Reception control part 15 Data processing unit 20 Navigation device

Claims (4)

In an in-vehicle wireless communication device that transmits transmission information by relaying with a wireless communication device mounted on another vehicle,
A range including an intersection based on each position information of the plurality of other vehicles when it is determined that the host vehicle is approaching the intersection and the position information transmitted from the wireless communication devices of the plurality of other vehicles can be received. And if it is determined that there are multiple wireless communication devices installed in other vehicles near the intersection center, which is the range where radio waves transmitted from the vehicle's wireless communication device reach, the other closest to the center of the intersection A vehicle-mounted wireless communication device, wherein a wireless communication device mounted on a vehicle is selected and designated as a relay wireless communication device, and transmission information is transmitted to the designated relay wireless communication device. The in-vehicle wireless communication device according to claim 1 , wherein transmission of the transmission information is stopped when the transmitted transmission information is received from the relay wireless communication device. In a wireless communication system that relays transmission information through an in-vehicle wireless communication device,
In the first in-vehicle wireless communication device, it is determined that the host vehicle on which the first in-vehicle wireless communication device is mounted is approaching an intersection, and the position information transmitted from the wireless communication devices of a plurality of other vehicles is used. When received, based on the position information of the plurality of other vehicles, mounted on the other vehicle in the vicinity of the intersection center where the radio wave transmitted from the wireless communication device of the host vehicle reaches the range including the intersection If it is determined that there are a plurality of wireless communication devices, the wireless communication device mounted on the other vehicle located closest to the center of the intersection is selected and designated as the relay wireless communication device, and the designated relay wireless communication device Send information,
The second in-vehicle wireless communication device relays transmission information from the first in-vehicle wireless communication device when it is determined that the first in-vehicle wireless communication device is designated as a relay wireless communication device. A wireless communication system, characterized by: The wireless communication system according to claim 3 , wherein the first in-vehicle wireless communication device stops transmitting the transmission information when the transmitted transmission information is received from the relay wireless communication device.

Images