JP2009239458A - Vehicle communication relay device, and vehicle communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle communication relay device and a vehicle communication system that improve communication quality by suppressing communication traffic even in a state wherein a plurality of transmission antennas are installed nearby. <P>SOLUTION: The vehicle communication relay device relays communication between in-vehicle communication devices mounted on vehicles or communication between an in-vehicle communication device and a road-side communication device provided on a road side. Then the vehicle communication relay device includes a relay transmission necessity determination means of determining whether reception information needs to be relayed, a transmission source determination means of acquiring information associated with an arrangement of transmission sources of reception information, and a transmission antenna selection means of selecting a transmission antenna to be used to relay and transmit information received from a plurality of transmission antennas based upon the information on the arrangement of the transmission sources. The vehicle communication system uses the vehicle communication relay device. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle communication relay device and a vehicle communication system, and can be applied to, for example, an inter-vehicle communication system or a road-to-vehicle communication system.

  Conventionally, the inter-vehicle communication system and the road-to-vehicle communication system are based on wireless communication technology using autonomous distributed control, and the in-vehicle communication devices or the in-vehicle communication device and the roadside communication device directly communicate with each other, Its purpose is to provide safety support and entertainment information.

However, there is a problem that communication becomes difficult in an environment where there is no direct view between communication devices. As a countermeasure to this problem, a method is generally known in which a relay device is installed at a place where two communication devices are visible from each other, and the relay device relays communication information (see Patent Documents 1 and 2). . At this time, generally, one antenna is attached to one relay device. In addition, it is supposed that more stable relay communication can be performed by installing a plurality of relay devices instead of one at one intersection.
JP 2005-227978 A JP 2005-191691 A

  However, in the conventional method, in consideration of the influence of the surrounding environment, etc., when installing a plurality of relay devices, all the relay devices relay the same information, and communication traffic becomes larger than necessary, resulting in communication. The capacity will be compressed and the communication quality will be greatly affected.

  Therefore, a vehicle communication relay device and a vehicle communication system that can suppress communication traffic and improve communication quality even in the situation where a plurality of transmission antennas are installed in the vicinity are desired.

  A first aspect of the present invention is a vehicle communication relay device that relays communication between in-vehicle communication devices mounted on a vehicle or communication between the in-vehicle communication device and a roadside communication device provided on the road side. Relay transmission necessity determining means for determining whether or not it is necessary to perform relaying, (2) transmission source determining means for acquiring information relating to the arrangement of the transmission source of received information, and (3) transmission source Transmission antenna selection means for selecting a transmission antenna to be used for relay transmission of information received from a plurality of transmission antennas based on the information relating to the arrangement of the transmission antennas.

  The second aspect of the present invention includes one or a plurality of vehicle communication relay devices that relay communication between in-vehicle communication devices mounted on a vehicle or communication between the in-vehicle communication device and a roadside communication device provided on the road side. In the vehicle communication system, the vehicle communication relay device according to the first aspect of the present invention is applied as at least a part of the vehicle communication relay device.

  According to the present invention, it is possible to suppress communication traffic and improve communication quality even in a situation where a plurality of transmission antennas are installed in the vicinity.

(A) First Embodiment Hereinafter, a first embodiment of a vehicle communication relay device and a vehicle communication system according to the present invention will be described in detail with reference to the drawings. The vehicle communication system according to the first embodiment is a vehicle-to-vehicle communication system, and the vehicle communication relay device according to the first embodiment (hereinafter simply referred to as a relay device) functions to relay vehicle-to-vehicle communication. The vehicle communication system according to the first embodiment, for example, exchanges information such as the position and speed of the own vehicle at regular intervals between in-vehicle communication devices via a relay device, and avoids a vehicle collision based on the information. System.

(A-1) Configuration of First Embodiment FIG. 2 is an explanatory diagram showing an arrangement of components of the vehicle communication system 10 according to the first embodiment.

  In FIG. 2, a plurality (four examples in FIG. 2) of relay apparatuses 1-1 to 1-4 are installed in the area of the intersection 5, and each relay apparatus 1-1 to 1-4 has 1. Two transmission / reception antennas 2-1 to 2-4 are provided. In-vehicle communication devices 4-1 to 4-6 are mounted on one or a plurality of vehicles 3-1 to 3-6 (six examples in FIG. 2) heading toward or away from the intersection 5, respectively. Has been.

  Each of the relay devices 1-1 to 1-4 is installed at a position that is well-viewed from the in-vehicle communication devices 4-1 to 4-6 of the vehicles 3-1 to 3-6 traveling in any direction. . In addition, the transmission / reception power capable of communicating with the in-vehicle communication devices 4-1 to 4-6 of the vehicles 3-1 to 3-6 within a distance that may cause a collision of the vehicle at the intersection 5 is set as the relay devices 1-1 to 1. -4. In other words, the in-vehicle communication devices 4-1 to 4-6 (accordingly, the vehicles 3-1 to 3-6) and the relay devices 1-1 to 1-4 are within a line-of-sight distance.

  FIG. 2 shows the in-vehicle communication devices 4-1 to 4-3 of the vehicles 3-1 to 3-3 traveling in the east direction on the west side road of the intersection 5 and the north side of the roadway on the south side of the intersection 5. It shows a case in which the in-vehicle communication devices 4-4 to 4-6 of the vehicles 3-4 to 3-6 are inferior and cannot communicate directly. In this case, any of the in-vehicle communication devices 4-1 to 4-3 and any of the in-vehicle communication devices 4-4 to 4-6 are connected via the relay device 1 (any one of 1-1 to 1-4). , Exchange information such as the position and speed of the vehicle.

  In the case of the first embodiment, the relay devices 1-1 to 1-4 can communicate with each other through a relay device channel different from the communication channel between the in-vehicle communication device and the relay device. The relay device channel may be a wireless channel or a wired channel. FIG. 2 shows a case where the relay apparatuses 1-1 to 1-4 are connected by the communication line 6.

  Each of the in-vehicle communication devices 4-1 to 4-6 is similar to the existing in-vehicle communication device, and the direct communication method between the in-vehicle communication devices is the same as the existing one.

  FIG. 1 is a block diagram illustrating a functional configuration of a relay device 1 (corresponding to 1-1 to 1-4) according to the first embodiment. The relay device 1 includes, for example, a transmission / reception configuration with a vehicle-mounted communication device by hardware, a transmission / reception configuration with another relay device by hardware, a CPU and a program executed by the CPU (for example, encounter collision prevention support Application), but can be functionally represented in FIG.

  The relay device 1 includes a reception unit 111, a relay transmission necessity determination unit 112, a transmission source determination unit 113, a relay device selection unit 114, a transmission unit 115, a transfer content transmission unit 121, a transfer content reception unit 122, and a control unit 131. Yes.

  The reception unit 111 receives information from the in-vehicle communication device 4 (4-1 to 4-6) or another relay device, and provides necessary information to the relay transmission necessity determination unit 112 and the transmission source determination unit 113. To do. For example, in the case of a safe driving support application, the information to be provided can include unique information such as the position and speed of each vehicle, and information such as how many vehicles are around.

  The relay transmission necessity determination unit 112 determines whether or not the information received from the reception unit 111 needs to be relayed, and provides the result to the transmission source determination unit 113. As a criterion for determination, for example, it is determined that relaying is necessary when information is sent from a vehicle (an in-vehicle communication device) whose distance from itself is equal to or less than a threshold distance. In addition, information sent as emergency information (information from police cars, fire engines, etc., traffic rule violation information; a flag to that effect may be included in emergency information) is relayed Judge that it is necessary.

  Based on the information provided from the reception unit 111 and the relay transmission necessity determination unit 112, the transmission source determination unit 113 extracts information (for example, position and / or direction) related to the arrangement of the transmission source (the in-vehicle communication device). In the above, the provided information and the arrangement information of the transmission source are provided to the relay device selection unit 114. Specifically, the location information of the transmission source is determined by looking at the contents of the received information. For example, in the case of transmission / reception by packet communication, the position information of the transmission source inserted in a predetermined part of the header part or the data part is extracted. Alternatively, the position information of the transmission source is extracted by correcting the extracted position information in consideration of the speed, the traveling direction, and the elapsed time from the transmission time. The transmission source determination unit 113 further captures the direction of the transmission source from the position information of the transmission source (the in-vehicle communication device).

  Note that the transmission source determination unit 113 may discard the received information when another relay device is the transmission source.

  The relay device selection unit 114 is based on information such as transmission source position information in the information received from the transmission source determination unit 113 and radio wave propagation characteristics (reception power, bit error rate, packet error rate, etc.) related to each relay device. This selects a relay device that is optimal for relay transmission. For example, based on the location information of the transmission source and the location information of each relay device, the relay device having the best radio wave propagation characteristics for transmitting from the relay device in a direction not including the transmission source is selected. In the arrangement of components as shown in FIG. 2, when any relay device 1 receives information transmitted by the vehicle 3-1, the vehicle 3 out of a plurality of roads extending from the center of the intersection 5 and having different directions. The relay device most suitable for transmission to roads in three directions other than the road including -1 is selected.

  Here, the most suitable means that the parameter indicating the communication quality such as the received power, the bit error rate, and the packet error rate is the best in the service area around the target intersection 5 by the safe driving support application. One or more parameters may be applied. In the latter case, an optimal relay device may be determined using a quality evaluation value obtained by weighted addition or the like. The quality evaluation value indicating the communication quality may be obtained each time, but considering the processing load of the relay device, etc., each position of the transmission source (for example, the service area is divided into a plurality of sections, and the same section has the same position) It is preferable to obtain a quality evaluation value indicating communication quality according to the communication device) at the time of installing the relay device, store it in the relay device, and apply it. The quality evaluation values corresponding to the positions of the transmission sources stored in all the relay apparatuses 1-1 to 1-4 are the same.

  The reason why the relay device to be used is selected from the position of the transmission source (and the traveling direction) is that the direction with the best communication quality differs depending on the location of the relay device.

  The transmission means 115 transmits relay information when the relay device 1 is selected as a relay device that transmits relay information. When the relay device 1 is selected as a relay device that transmits relay information, the relay device 1 is selected not only by the relay device selection unit 114 of the relay device 1, but also by the relay device selection unit 114 of another relay device. Including the case. In the latter case, as will be described later, relay information is transferred from another relay apparatus. Further, the transmission unit 115 may transmit the relay information to be transmitted by including information indicating that the relay has been performed or information indicating the relay device.

  The transfer content transmission unit 121 transfers the relay information to the selected other relay device when it is determined by the relay device selection unit 114 that the relay device other than the relay device 1 transmits the relay information. is there.

  The transfer content receiving unit 122 receives the relay information to be transmitted from the relay device 1 transferred from the transfer content transmitting unit 121 of another relay device. The transfer content receiving unit 122 gives the received relay information to the transmitting unit 115 for transmission. The transfer content receiving unit 122 stores the relay information or the header information given to the transmission unit 115 for a predetermined period, and even when the same relay information arrives from a plurality of other relay devices, Only the relay information may be given to the transmission means 115.

  The control unit 131 is the entire relay device 1, in other words, the reception unit 111, the relay transmission necessity determination unit 112, the transmission source determination unit 113, the relay device selection unit 114, the transmission unit 115, the transfer content transmission unit 121, and the transfer content. The receiving means 122 is controlled so that each means exhibits the above-described functions.

(A-2) Operation of First Embodiment Next, the operation of the vehicle communication system 10 according to the first embodiment will be described in detail with reference to the flowchart of FIG. Here, FIG. 3 is a flowchart showing the operation of the relay apparatus 1 (1-1 to 1-4). In the following description, each of the in-vehicle communication devices 4-1 to 4-6 exchanges information such as the position and speed of the vehicles 3-1 to 3-6 on which the in-vehicle communication devices 4-1 to 4-6 are mounted with each other. Suppose that

  When the relay device 1 starts a service (relay service) related to the safe driving support application (step S101), processing (step S111) for acquiring (receiving) information that may be relayed by the receiving unit 111, and other processing The process proceeds to a process of receiving relay information to be transmitted by the relay apparatus from the relay apparatus (step S121).

  When the information that may be relayed by the receiving unit 111 is acquired, the relay transmission necessity determining unit 112 determines whether relay transmission is necessary (steps S112 and S113).

  In the case of information that needs to be relayed (relay information), the position and direction of the transmission source are determined by the transmission source determination unit 113 (step S114), and then the relay device selection unit 114 transmits the relay information. It is determined which relay device to perform and whether the selected relay device is the relay device (steps S115 and S116). When the relay device performs relay, the transmission unit 115 transmits relay information (step S117). On the other hand, when the relay device 1 does not perform relay, other relays to be relayed are performed. The relay information is transferred to the device (step S118).

  When relay information to be relayed by the relay device 1 is transferred from another relay device and acquired (step S121), the transmission unit 115 transmits the transferred relay information (step S117).

  When it is determined that relay transmission is not necessary (step S113), when relay information is transmitted (step S117), or when relay information is transferred to another relay device (step S118), the service is terminated. Whether or not (step S102). If it is determined that the service is not terminated, the process proceeds to the above-described steps S111 and S121, and the above-described processing is repeated. If it is determined that the service has ended, the service is ended (step S103).

(A-3) Effects of the first embodiment According to the first embodiment, the received information is relayed and transmitted using only the relay device with the best communication quality, so that unnecessary traffic is generated. Relay transmission without any problem.

(B) Second Embodiment Next, a vehicle communication relay device and a vehicle communication system according to a second embodiment of the present invention will be described in detail with reference to the drawings. The vehicle communication system according to the second embodiment is a vehicle-to-vehicle communication system, and the vehicle communication relay device according to the second embodiment (hereinafter simply referred to as a relay device) functions to relay vehicle-to-vehicle communication.

(B-1) Configuration of Second Embodiment FIG. 4 is an explanatory diagram showing the arrangement of components of the vehicle communication system 10A according to the second embodiment, and is the same as FIG. 2 according to the first embodiment. The same and corresponding parts are denoted by the same reference numerals.

  In FIG. 4, in the vehicle communication system 10 </ b> A according to the second embodiment, a plurality of (four examples in FIG. 2) locations in the intersection 5 with good line-of-sight for the vehicles 3-1 to 3-6 heading for the intersection 5. Each is provided with transmission / reception antennas 2-1 to 2-4 connected to the relay apparatus 1A according to the second embodiment only via feeders 7-1 to 7-4. In addition, it may replace with the transmitting / receiving antennas 2-1 to 2-4, and you may make it install the pair of the transmitting antenna and receiving antenna which are approaching.

  FIG. 4 also shows the in-vehicle communication devices 4-1 to 4-3 of the vehicles 3-1 to 3-3 traveling in the east direction on the west side road of the intersection 5 and the north side of the roadway on the south side of the intersection 5. It shows a case in which the in-vehicle communication devices 4-4 to 4-6 of the vehicles 3-4 to 3-6 are inferior and cannot communicate directly. In the case of the second embodiment, any one of the in-vehicle communication devices 4-1 to 4-3 and any one of the in-vehicle communication devices 4-4 to 4-6 are located via the relay device 1A. Exchange information such as. The transmission / reception antenna that receives the relay information and the transmission / reception antenna that transmits the relay information do not have to be the same when the relay apparatus 1A is used. In the second embodiment, at least the transmission / reception that transmits the relay information. The antenna is selected in consideration of communication quality and the like.

  Also in 2nd Embodiment, each vehicle-mounted communication apparatus 4-1 to 4-6 is the same as the existing vehicle-mounted communication apparatus, and the direct communication method between vehicle-mounted communication apparatuses is the same as the existing one. .

  FIG. 5 is a block diagram illustrating a functional configuration of the relay device 1A according to the second embodiment. The same reference numerals are given to the same or corresponding parts as those in FIG. 1 according to the first embodiment. Yes. The relay device 1A is realized, for example, by a hardware transmission and reception configuration with an in-vehicle communication device, and a program executed by the CPU and the CPU (for example, an encounter collision prevention support application). This can be represented in FIG.

  The relay apparatus 1A according to the second embodiment includes a reception unit 111A, a relay transmission necessity determination unit 112, a transmission source determination unit 113, a transmission unit 115A, a relay antenna selection unit 116A, and a control unit 131A.

  The relay transmission necessity determination unit 112 and the transmission source determination unit 113 are the same as those in the first embodiment, and the description of the functions thereof is omitted.

  The transmission / reception antennas 2-1 to 2-4 are connected to the reception unit 111A. The reception unit 111A acquires the reception information from the transmission / reception antennas 2-1 to 2-4, and determines the relay transmission necessity determination unit 112 and the transmission source. This is given to the judging means 113. When a plurality of transmission / reception antennas receive the same information, the reception unit 111A may perform selectivity diversity processing or synthesis diversity processing and output the reception information after processing.

  In the case of the second embodiment, the transmission source determination unit 113 provides the relay antenna selection unit 116 with information on the position and direction of the transmission source obtained by extraction.

  The relay antenna selection unit 116 selects an optimal transmission / reception antenna for relay transmission from information received from the transmission source determination unit 113 and information such as radio wave propagation characteristics. The selection method is the same as the selection method of the relay device selection unit 114 in the first embodiment.

  The transmitting / receiving antennas 2-1 to 2-4 are connected to the transmitting unit 115A, and the transmitting unit 115A receives the relay information from the transmitting / receiving antenna (any one of 2-1 to 2-4) selected by the relay antenna selecting unit 116. Send it.

(B-2) Operation | movement of 2nd Embodiment Next, operation | movement of 10 A of vehicle communication systems which concern on 2nd Embodiment is explained in full detail, referring the flowchart of FIG. Here, FIG. 6 is a flowchart showing the operation of the relay apparatus 1A, and the same and corresponding steps as those in FIG. 3 according to the first embodiment are denoted by the same reference numerals. In the following description, each of the in-vehicle communication devices 4-1 to 4-6 exchanges information such as the position and speed of the vehicles 3-1 to 3-6 on which the in-vehicle communication devices 4-1 to 4-6 are mounted with each other. Suppose that

  When the relay device 1A starts a service (relay service) (step S101), the relay information is acquired by the receiving unit 111A (step S131).

  Subsequently, the relay transmission necessity determination unit 112 determines whether or not relay transmission is necessary (steps S132 and S133). If the information needs to be relayed, the transmission source determination unit 113 determines the position and direction of the transmission source (step S134). Subsequently, the transmission / reception antenna for transmitting the relay information is selected by the relay antenna selection unit 116 (step S135), and the relay information is transmitted from the transmission / reception antenna selected by the transmission unit 115A (step S136).

  When it is determined that relay transmission is not necessary (step S133) or when relay information is transmitted (step S136), it is determined whether or not the service is completed (step S102). If it is determined that the service is not terminated, the process proceeds to step S131 described above, and the above-described processing is repeated. If it is determined that the service has ended, the service is ended (step S103).

(B-3) Effect of the Second Embodiment According to the second embodiment, the relay apparatus transmits the received relay information from the transmission / reception antenna with the best communication quality. It is possible to perform relay transmission without generating. In addition, since relay information is transmitted from a transmission / reception antenna that provides the best communication quality, it is possible to eliminate the influence of interference due to multiple waves.

(C) Other Embodiments In the description of each of the above embodiments, various modified embodiments have been referred to. However, modified embodiments as exemplified below can be cited.

  In each of the above-described embodiments, the vehicle communication system according to the present invention is applied to the inter-vehicle communication system in which the relay device is interposed in the communication between the in-vehicle communication devices, but the relay is performed for the communication between the in-vehicle communication device and the roadside communication device. The vehicle communication system according to the present invention can be applied to a road-to-vehicle communication system in which a device is interposed, and further includes a communication between an in-vehicle communication device and a communication between the in-vehicle communication device and the roadside communication device. The vehicle communication system according to the present invention can be applied.

  In the first embodiment, all the relay devices have both the relay information reception function and the transmission function. However, all or some of the relay devices have the relay information reception function or transmission function. It may correspond to only one side. Also in the second embodiment, it is possible to divide a device that is responsible for the relay information reception function and a device that is responsible for the relay information transmission function, and to transfer information between both devices.

  In each of the above-described embodiments, one relay device or transmission / reception antenna that performs transmission of relay information is shown as one, but a plurality of selections may be printed. For example, when a transmission / reception antenna having directivity (for example, loose directivity) is applied and there are a plurality of transmission directions different from the direction of the transmission source, a plurality of relay devices or transmission / reception antennas are selected. May be. In addition, for example, when the number of roads radiated from the intersection center is a predetermined number or more (for example, five or more) (a more complex intersection than a crossroad intersection), a plurality of relay apparatuses or transmission / reception antennas may be selected. .

  Moreover, you may make it apply combining the technical idea of 1st Embodiment, and the technical idea of 2nd Embodiment. For example, each of a plurality (m) of relay apparatuses includes a plurality (n) of transmission / reception antennas, and selects one to be used for transmission from a total of m × n transmission / reception antennas. May be. Also, a relay device having a plurality of transmission / reception antennas and a relay device having one transmission / reception antenna may be mixed.

  In each of the above-described embodiments, the information from the vehicle moving away from the intersection is also relayed. However, the information from the vehicle moving away from the intersection is not relayed or transmitted from the vehicle moving away from the intersection. The relay transmission priority may be set lower than the relay transmission priority of information from a vehicle approaching the intersection. Thereby, the relay traffic can be significantly reduced. Whether or not to move away from the intersection can be grasped by storing the past position (source position) of the vehicle and tracking the position.

It is a block diagram which shows the functional structure of the relay apparatus which concerns on 1st Embodiment. It is explanatory drawing which shows arrangement | positioning of the component of the vehicle communication system which concerns on 1st Embodiment. It is a flowchart which shows operation | movement of the relay apparatus in 1st Embodiment. It is explanatory drawing which shows arrangement | positioning of the component of the vehicle communication system which concerns on 2nd Embodiment. It is a block diagram which shows the functional structure of the relay apparatus which concerns on 2nd Embodiment. It is a flowchart which shows operation | movement of the relay apparatus in 2nd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 1-1-1-4, 1A ... Relay apparatus, 2-1-2-4 ... Transmission / reception antenna, 4-1-4-6 ... In-vehicle communication apparatus, 6 ... Communication line 10, 10A ... Vehicle communication system 111, 111A ... receiving means, 112 ... relay transmission necessity determining means, 113 ... transmission source determining means, 114 ... relay device selecting means, 115, 115A ... transmitting means, 116 ... relay antenna selecting means, 121 ... transfer content transmitting means 122, transfer content receiving means, 131, 131A, control means.

Claims (6)

In a vehicle communication relay device that relays communication between in-vehicle communication devices mounted on a vehicle, or communication between the in-vehicle communication device and a roadside communication device provided on the road side,
Relay transmission necessity determining means for determining whether or not the received information needs to be relayed;
Transmission source determination means for acquiring information related to the arrangement of the transmission source of the received information;
A vehicle communication relay device, comprising: a transmission antenna selection unit that selects a transmission antenna to be used for relay transmission of information received from a plurality of transmission antennas based on information relating to an arrangement of transmission sources.   All of the plurality of transmitting antennas are directly connected to the vehicle communication relay device, and further include transmitting means for transmitting information received from the transmitting antenna selected by the transmitting antenna selecting means. The vehicle communication relay device according to claim 1.   A plurality of transmission antennas to be selected by the transmission antenna selection means are respectively connected to different vehicle communication relay apparatuses, and the transmission antenna selected by the transmission antenna selection means is another vehicle communication relay apparatus. The vehicle communication relay device according to claim 1, further comprising transfer content transmission means for transferring the received information to the other vehicle communication relay device when connected to the vehicle.   When the transmitting antenna selected by the transmitting antenna selecting means is connected to the vehicle communication relay device, the transmitting antenna selecting means further includes transmitting means for transmitting information received from the transmitting antenna selected by the transmitting antenna selecting means. The vehicle communication relay device according to claim 3.   And further comprising transfer content receiving means for receiving information transferred and transmitted by another vehicle communication relay device, wherein the transmission means causes the information received by the transfer content receiving means to be transmitted from the transmitting / receiving antenna. Item 5. The vehicle communication relay device according to Item 4. In a vehicle communication system having one or more vehicle communication relay devices that relay communication between in-vehicle communication devices mounted on a vehicle, or communication between an in-vehicle communication device and a roadside communication device provided on the road side,
A vehicle communication system characterized by applying the vehicle communication relay device according to any one of claims 1 to 5 as at least a part of the vehicle communication relay device.

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