JP5691972B2 - Road-to-vehicle communication system, road-side communication control device, and road-side communication control program - Google Patents

Description

  The present invention relates to a road-vehicle communication system, a roadside communication control device, and a roadside communication control program. For example, the present invention can be applied to a road-to-vehicle communication system, a road-side communication control device, and a road-side communication control program for managing a vehicle passing through a gate provided with a road-side antenna.

  For example, in cement factories, mines, etc., dedicated vehicles such as dump trucks are used to transport crushed stones such as limestone mined at mining sites. There is a gate at the site entrance where crushed stones are loaded and unloaded, and a dedicated vehicle passes through the gate and enters or exits the site.

  In recent years, in the transportation work such as loading and unloading of loads, for example, a gate management system for specifying an approaching vehicle, managing the types of loads to be loaded, or managing the types of loads to be unloaded is required. Yes.

  In order to meet such demands, for example, on-board equipment for dedicated vehicles is installed near the gate using the DSRC (Dedicated Short Range Communications) technology applied in ITS (Intelligent Transport System). It has been proposed that a DSRC radio communicates with a DSRC antenna and performs gate management by specifying vehicle identification information.

  However, for example, since the gate equipment and the vehicle body are made of metal, the radio wave from the vehicle-mounted device may be reflected and the DSRC antenna may receive the reflected wave. In addition, when there is an adjacent gate, a radio wave from the vehicle-mounted device passing through the adjacent gate may enter and be received by the DSRC antenna.

  In such a case, the DSRC radio will erroneously detect the vehicle identification information, which may lead to mismanagement of the load, misdelivery, etc. False positives should be avoided.

  Conventionally, in a DSRC technique used in, for example, an expressway or a parking lot, there is a technique described in Patent Document 1 as a technique for avoiding erroneous detection due to a reflected wave.

  The technology described in Patent Document 1 is that a DSRC antenna emits radio waves when a loop coil is installed in a service area and the loop coil detects a vehicle in advance. As a result, radio waves can be emitted only when the vehicle passes through the gate. Therefore, even if a reflected wave enters the adjacent gate, the occurrence of erroneous detection is reduced.

JP 2006-270619 A

  However, the technique described in Patent Document 1 described above requires a loop coil to be installed in the service area. That is, in order to install the loop coil, a large-scale construction is required on the road.

  It is not practical to perform such a large-scale construction in a private company's factory or site because it requires repairing existing facilities and entails large repair costs. In particular, in a cement factory or mining site, since the construction is performed on the flow line of the vehicle, it is inevitable that the loading and unloading transportation work is stopped, and it is difficult to apply the technology described in Patent Document 1 as it is. It is.

  Further, as another method for detecting a vehicle passing through a gate, it is conceivable to use a sensor (for example, an ultrasonic sensor) instead of the loop coil. However, in mines, etc., the sensor itself may be damaged due to dust, etc. Even if there is no problem such as failure in the DSRC radio, if the sensor itself fails, radio waves are emitted to the DSRC radio. It is impossible to notify the operation timing of the system, and the original role cannot be realized.

  Furthermore, even if the sensor detects the vehicle in advance, if the vehicle enters the adjacent gate at the same timing, there is a possibility that it is affected by the reflected wave between the adjacent gate.

  Therefore, there is a need for a road-to-vehicle communication system, a roadside communication control device, and a roadside communication control program that can avoid erroneous detection of reflected waves and radio waves from adjacent gates without providing a large-scale facility. .

  In order to solve such a problem, the first aspect of the present invention includes (1) an antenna unit and (2) a vehicle which is provided in a vehicle and receives at least radio waves from the antenna unit. A plurality of in-vehicle devices that transmit radio waves including the radio wave, and (3) received radio wave intensity measuring means that detects the in-vehicle device identification information included in the radio wave signal captured by the antenna unit and measures the received radio wave intensity of the radio waves. (4) Based on the measured value of the received radio wave intensity of each OBE identification information measured by the received radio wave intensity measuring means, a temporal variation pattern of the received radio wave intensity of each OBE identification information is obtained, and each of the OBE A road-to-vehicle communication system comprising: a radio wave specifying unit that specifies a target radio wave based on a temporal variation pattern of received radio wave intensity of identification information.

  A second aspect of the present invention is a reflected wave detection device that detects a reflected wave based on radio waves from a plurality of vehicle-mounted devices provided in a vehicle, and is (1) antenna means and (2) captured by the antenna means. Received radio field intensity measuring means for detecting the in-vehicle device identification information contained in the received radio signal and measuring the received radio wave intensity of the radio wave, and (3) receiving each on-board device identification information measured by the received radio wave intensity measuring means. Based on the measurement value of the radio field strength, obtain the temporal variation pattern of the received radio field strength of each OBE identification information, and identify the target radio wave based on the temporal variation pattern of the received radio field strength of each OBE identification information A roadside communication control device comprising radio wave specifying means.

  A third aspect of the present invention is a reflected wave detection program for detecting a reflected wave based on radio waves from a plurality of vehicle-mounted devices provided in a vehicle, wherein (1) the radio wave signal captured by the antenna means is converted into a radio wave signal. Received radio wave intensity measuring means for detecting the received OBE identification information and measuring the received radio wave intensity of the radio wave, (2) Measured value of the received radio wave intensity of each OBE identification information measured by the received radio wave intensity measuring means Function as a radio wave identification means to determine the time variation pattern of the received radio wave intensity of each OBE identification information and identify the target radio wave based on the time fluctuation pattern of the received radio wave intensity of each OBE identification information It is a roadside communication control program characterized by making it carry out.

  According to the present invention, erroneous detection of reflected waves and radio waves from adjacent gates can be avoided without providing a large-scale facility.

It is a block diagram which shows the whole structure of the road-to-vehicle communication system of 1st Embodiment, and the internal structure of each component. It is a block diagram explaining the structure image of the gate management system of 1st Embodiment. It is explanatory drawing explaining the example of installation of the onboard equipment mounted in the vehicle of embodiment. It is explanatory drawing explaining the electromagnetic wave characteristic of the communication area of the antenna part of embodiment. It is a figure which shows the fluctuation pattern of the received radio wave intensity | strength of the electromagnetic wave from the onboard equipment of 1st Embodiment. It is a figure which shows the fluctuation pattern of the received radio wave intensity | strength of the electromagnetic wave of the three onboard equipment of 1st Embodiment. It is a figure which shows the fluctuation pattern also including the received radio wave intensity | strength of the reflected wave of 1st Embodiment. It is a flowchart explaining the detection method of the passing vehicle in the control apparatus of 1st Embodiment. It is a block diagram explaining the structure image of the gate management system of 2nd Embodiment.

(A) 1st Embodiment Below, it demonstrates, referring drawings for 1st Embodiment of the road-vehicle communication system of this invention, a roadside communication control apparatus, and a roadside communication control program.

  The first embodiment is a gate management system that employs, for example, DSRC technology, in which the present invention is applied to a system that erroneously detects a reflected wave reflected by a vehicle body, a gate, or the like when a radio wave emitted by the vehicle-mounted device is reflected. Illustrate.

(A-1) Configuration of the First Embodiment FIG. 1 is a configuration diagram showing the overall configuration of the road-to-vehicle communication system of the first embodiment and the internal configuration of each component.

  In FIG. 1, a road-vehicle communication system 1 according to the first embodiment includes an antenna unit 11, a radio device 12, a control device 13, a network switch 14, and a plurality of vehicles (three in FIG. 1) mounted on a vehicle 51. The container 21 (21-1 to 21-3) is included. In the following description, when a common configuration of the vehicle-mounted device is described, the vehicle-mounted device is described as the vehicle-mounted device 21.

  The vehicle 51 is a vehicle on which crushed stones can be loaded, for example. The vehicle 51 is equipped with a plurality of vehicle-mounted devices 21-1 to 21-3.

  Here, the installation method of the vehicle-mounted devices 21-1 to 21-3 will be described with reference to FIG. FIG. 3 is an explanatory diagram illustrating an installation example of the vehicle-mounted devices 21-1 to 21-3 in the vehicle 51.

  As illustrated in FIG. 3, the plurality of vehicle-mounted devices 21-1 to 21-3 are installed at intervals along the traveling direction of the vehicle 51. That is, it arrange | positions at intervals so that the antenna part 11 can receive the electromagnetic wave which each onboard equipment 21-1 to 21-3 emits with a time difference. The installation interval is not particularly limited, and may be determined according to the operation or may be an arbitrary interval.

  The vehicle-mounted devices 21-1 to 21-3 communicate with the antenna unit 11 provided near the gate, and hold unique vehicle-mounted device identification information.

  For example, an existing ETC on-vehicle device or a DSRC technology-compatible on-vehicle device can be applied to the on-vehicle devices 21-1 to 21-3, and includes an antenna unit and an on-vehicle device body.

  Moreover, the onboard equipment 21-1 to 21-3 has the transmission / reception part 211 and the vehicle information storage part 212, as shown in FIG. In addition, all the onboard equipment 21-1 to 21-3 may have the same configuration.

  The vehicle information storage unit 212 stores, for example, vehicle identification information (for example, a license plate), vehicle classification information indicating a vehicle classification (for example, a general vehicle, a dedicated vehicle, etc.), and the like. The vehicle information storage unit 212 may be a memory built in the vehicle-mounted device 21 or an IC card that stores vehicle information such as a so-called ETC card.

  When receiving the radio wave emitted by the antenna unit 11, the transmission / reception unit 211 transmits a radio wave signal including unique vehicle-mounted device identification information, vehicle identification information stored in the vehicle information storage unit 212, and the like.

  The antenna unit 11 is a roadside antenna unit that performs communication with the vehicle-mounted device 21. For example, the antenna unit 11 can apply the antenna technology based on the standardization technology according to the ARIB STD-T75DSRC system standardization standard.

  The antenna unit 11 is connected to the wireless device 12 via a cable 15 (for example, a coaxial cable), and emits radio waves constantly or at a predetermined cycle under the control of the wireless device 12.

  The antenna unit 11 has very high directivity, and emits radio waves toward the road in order to detect the vehicle-mounted device 11. For example, the antenna unit 11 emits radio waves having a predetermined frequency at intervals of several milliseconds. The antenna unit 11 receives the radio wave transmitted by the vehicle-mounted device 21 that has received the emitted radio wave, and gives the received signal to the wireless device 12.

  The antenna unit 11 is installed in the vicinity of the gate in order to detect the vehicle 51 passing through the gate.

  FIG. 2 is an explanatory diagram illustrating an overall configuration image of the road-vehicle communication system 1. In the example of FIG. 2, the road 53 leads to a site such as a cement factory, and the vehicle 51 can enter the site by traveling on the road 53. Further, the gate 52 is provided on the road 53 near the site entrance.

  In FIG. 2, the antenna unit 11 is provided above the gate 52 in order to detect the vehicle 51 passing through the gate 52, and is installed so as to emit radio waves toward the road 53.

  In addition, in order to detect the vehicle 51, the installation position of the antenna part 11 should just be a position which can communicate with the vehicle equipment 21 of the vehicle 51, for example, the pillar part of the gate 52 and the antenna part 11 are installed. It may be provided on a dedicated arm or column portion.

  The wireless device 12 controls the antenna unit 11 via the cable 15 and performs modulation / demodulation processing, signal processing, and the like. The wireless device 12 can apply communication processing standardized by, for example, the ARIB STD-T75DSRC system standardization standard.

  The wireless device 12 analyzes the vehicle-mounted device identification information based on the radio wave signal received by the antenna unit 11 and measures the received radio wave intensity of the radio wave for each vehicle-mounted device identification information. Further, the wireless device 12 gives the measured value of the received radio wave intensity of each vehicle-mounted device identification information to the control device 13 via the network switch 14.

  The wireless device 12 obtains the number of radio waves received per predetermined time interval for each vehicle-mounted device identification information, and gives the number of radio waves received for each vehicle-mounted device identification information to the control device 13.

  As illustrated in FIG. 1, the wireless device 12 includes a transmission / reception unit 121, a reception intensity measurement unit 122, an information detection unit 123, and a detection information transmission unit 124. The wireless device 12 is a device having, for example, a communication circuit, a CPU, a storage unit (for example, ROM, RAM, etc.) and an input / output interface, as in the case of an existing wireless device, and the CPU 121 is stored in the ROM. The various functions of the wireless device 12 are realized by executing the processing program.

  The transmission / reception unit 121 gives a transmission signal to be transmitted to the vehicle-mounted device 21 to the antenna unit 11 or receives a reception signal from the vehicle-mounted device 21 from the antenna unit 11. The transmission / reception processing by the transmission / reception unit 121 performs processing standardized by the ARIB STD-T75DSRC system standardization standard.

  The reception intensity measuring unit 122 detects the in-vehicle device identification information included in the reception signal from the transmission / reception unit 121 and measures the received radio wave intensity of the received radio wave for each on-vehicle device identification information.

  Here, the reception intensity measurement unit 122 measures the reception radio wave intensity of the radio wave received by the antenna unit 11. That is, the reception intensity measurement unit 122 receives not only the reception radio wave intensity of the radio wave from the vehicle-mounted device 21 of the vehicle 51 that passes through the gate, but also the reflected wave that is reflected by the gate and the vehicle body and received by the antenna unit 11. The radio wave intensity will also be measured. Even in this case, the reception intensity measuring unit 122 analyzes the in-vehicle device identification information of the reflected wave and gives the measured value of the received radio wave intensity for each on-vehicle device identification information to the control device 13 as detection information.

  The information detection unit 123 detects the vehicle identification information included in the reception signal received by the transmission / reception unit 121, and gives the detected vehicle identification information to the detection information transmission unit 124.

  The detection information transmission unit 124 gives the control device 13 the measured value of the received radio wave intensity for each vehicle-mounted device identification information measured by the reception intensity measurement unit 122 and the vehicle identification information detected by the information detection unit 123. .

  The control device 13 is a terminal device such as a personal computer, for example, and performs gate management control based on detection information from the wireless device 12.

  As shown in FIG. 1, the control device 13 includes a detection information acquisition unit 131, a reception intensity fluctuation analysis unit 132, a vehicle identification information specification unit 133, and a gate management control unit 134 as its main functions. The control device 13 includes, for example, a CPU, a storage unit (for example, ROM, RAM, etc.), an input / output interface, and the like. Various functions of the control device 13 are realized by executing an application. For example, the CPU is realized by executing a processing program stored in the ROM.

  The detection information acquisition unit 131 acquires detection information detected by the wireless device 12 via the network switch 14.

  The received intensity fluctuation analysis unit 132 is based on the temporal fluctuation pattern of the received radio field intensity measurement value of each in-vehicle identification information acquired from the wireless device 12, and whether or not the received intensity fluctuation analysis unit 132 is of the in-vehicle device 21 of the vehicle 51 that passes therethrough. Is to analyze.

  Here, a plurality of vehicle-mounted devices 21 are arranged in the vehicle 51 at a distance from each other. Therefore, when the vehicle 51 passes through the gate, the vehicle-mounted device 21 arranged in the front portion of the vehicle 51 starts communication with the antenna unit 11 earlier than the other vehicle-mounted devices 21, and then the vehicle 51 travels. Thus, the other vehicle-mounted device 21 sequentially starts communication with the antenna unit 11.

  At this time, the measured value of the received radio wave intensity gradually increases as the vehicle-mounted device 21 approaches the antenna unit 11, and the measured value of the received radio wave intensity becomes maximum when the vehicle-mounted device 21 approaches the antenna unit 11 most closely. The measured value attenuates as the vehicle-mounted device 21 moves away from the antenna unit 11.

  Therefore, when the vehicle 51 passes through the gate, the temporal variation pattern of the measurement value of the received radio wave intensity of each onboard equipment identification information shows the same or similar characteristics.

  In addition, since a plurality of vehicle-mounted devices 21 are provided, the variation pattern of the measured value is continuously and quantitatively performed every predetermined time. Further, since there is no obstacle between the vehicle-mounted device 21 and the antenna unit 11 and the antenna unit 11 receives a straight wave, the fluctuation pattern of the measured value of the received radio wave intensity from the vehicle-mounted device 21 is a distortion or the like. There is no increase or decrease.

  On the other hand, the reception intensity fluctuation analysis unit 132 also obtains a fluctuation pattern of a measured value of the received radio wave intensity of a reflected wave reflected on, for example, a vehicle hood. The fluctuation pattern of the measured value of the received radio wave intensity of the reflected wave depends on the external environment, but a delay or distortion occurs until the antenna unit 11 receives the wave. Different from 21.

  Therefore, the reception intensity fluctuation analysis unit 132 distinguishes between a fluctuation pattern having regularity and a regularity in measurement values of received radio wave intensity of a plurality of vehicle-mounted device identification information and a fluctuation pattern of measurement values that are not so. Then, it is determined whether or not the vehicle-mounted device 21 of the passing vehicle 51 is used.

  When vehicle reception information fluctuation analyzing section 132 determines that vehicle identification information specifying section 133 has a fluctuation pattern of the measured value of the received radio wave intensity of vehicle-mounted device 21 of passing vehicle 51 (that is, the passage of vehicle 51 is detected). And) identifying the vehicle identification information included in the received signal.

  The gate management control unit 134 performs predetermined gate management control based on the vehicle identification information specified by the vehicle identification information specifying unit 133. The gate management control performed by the gate management control unit 134 is not particularly limited, and various management controls can be performed. For example, the gate management control unit 134 can determine whether to classify a general vehicle and a dedicated vehicle, perform a gate opening / closing process associated with the passage of the vehicle 51, or manage the type of load.

(A-2) Operation of the First Embodiment Next, an operation of processing for avoiding erroneous detection of reflected waves by the road-to-vehicle communication system 1 of the first embodiment will be described with reference to the drawings.

  In FIG. 2, a vehicle 51 on which a plurality of vehicle-mounted devices 21-1 to 21-3 are mounted travels on a road 53 and approaches a gate 52 provided near the site entrance.

  At this time, in order to detect that the vehicle 51 has entered the communication area, the wireless device 12 gives a transmission signal to the antenna unit 11 so as to transmit radio waves at all times.

  Here, FIG. 4 is an explanatory diagram illustrating the radio wave characteristics of the communication area of the antenna unit 11. FIG. 4 shows the radio zone of the antenna unit 11 and the reception level in the radio zone. As shown in FIG. 4, the radio wave from the antenna unit 11 is emitted toward the road 53, and the radio wave intensity at which the antenna unit 11 receives the radio wave from the vehicle-mounted device 21 increases as it approaches the antenna unit 11. It is set to be strong.

  When the vehicle 51 enters the communication area of the antenna unit 11, the vehicle-mounted devices 21-1 to 21-3 sequentially receive radio waves from the antenna unit 11. When the on-vehicle devices 21-1 to 21-3 receive the radio wave from the antenna unit 11, the on-vehicle devices 21-1 to 21-3 transmit radio waves including the on-vehicle device identification information and the vehicle identification information.

  At this time, since the vehicle-mounted devices 21-1 to 21-3 mounted on the vehicle 51 are arranged at intervals along the traveling direction, the vehicle-mounted device 21-1 disposed in front of the vehicle 51. However, a stronger radio wave is received before the other vehicle-mounted devices 21-2 and 21-3, and the radio wave is transmitted.

  Thereafter, the vehicle-mounted devices 21-2 and 21-3 sequentially receive the radio waves from the antenna unit 11 and send out the radio waves.

  Note that when the wireless device 12 starts communication with the vehicle-mounted devices 21-1 to 21-3, the wireless device 12 controls the antenna unit 11 to transmit radio waves at a predetermined timing (for example, timing of several ms). Thereby, the response timing of onboard equipment 21-1 to 21-3 can also be made constant.

  The antenna unit 11 receives all incoming radio waves and gives all radio signals received to the radio unit 12.

  At this time, the radio wave received by the antenna unit 11 is reflected not only by the radio waves emitted by the vehicle-mounted devices 21-1 to 21-3 but also by, for example, the gate surface or the vehicle body of the vehicle 51, and the antenna unit 11 also receives the reflected wave. The radio wave signal of the reflected wave is also given to the wireless device 12.

  When the wireless device 12 receives the reception signal from the antenna unit 11, the wireless device 12 analyzes the in-vehicle device identification information included in the reception signal, measures the reception radio wave intensity of the radio wave from each on-vehicle device, and A measured value of the received radio wave intensity is given to the control device 13.

  FIG. 8 is a flowchart illustrating a method for detecting a passing vehicle in the control device 13.

  When the control device 13 obtains the measurement value of the received radio wave intensity of each on-vehicle device identification information from the wireless device 12 (S101), the control device 13 sets the measurement value of the received radio wave strength for each on-vehicle device identification information in time series. (S102), the fluctuation pattern of the measured value of the received radio wave intensity is obtained for each vehicle-mounted device identification information (S103).

When the control device 13 detects that the received radio wave intensity changes at the same interval at predetermined intervals based on the fluctuation pattern of the measured value of the received radio wave intensity of each in-vehicle identification information, the vehicle 51 It is determined that it has passed through the gate (S104, S105). Otherwise, it is determined that the waveform is a reflected wave (S104, S105).
FIG. 5 is a diagram showing a fluctuation pattern of the received radio wave intensity of radio waves from a certain vehicle-mounted device 21. As illustrated in FIG. 5, the control device 13 can set the detection start time of the measurement value of the received radio wave intensity as the time when the communication area is entered and the time point when the measurement value is detected as the time when the communication area exits.

  In FIG. 5, the measured value of the received radio wave intensity increases as the vehicle-mounted device 21 approaches the antenna unit 11 after entering the communication area. Then, the measured value of the received radio wave intensity becomes the maximum when the vehicle-mounted device 21 comes closest to the antenna unit 11, and then the measured value of the received radio wave intensity from the directivity of the antenna unit 11 when the vehicle 51 passes through the antenna unit 11. Decreases sharply.

  FIG. 6 is a diagram showing fluctuation patterns of the received radio wave intensity of the radio waves of the three on-vehicle devices 21-1 to 21-3. The vehicle-mounted devices 21-1 to 21-3 are assumed to have the same radio wave transmission conditions such as radio wave transmission intensity.

  In FIG. 6, the control device 13 sets the detection start time of the measurement value of the received radio wave intensity of the radio wave from the vehicle-mounted device 21-1 provided in the forefront in the traveling direction of the vehicle 51 as the time of entering the communication area vehicle. The end point of detection of the measured value of the received radio wave intensity of the radio wave from the vehicle-mounted device 21-3 provided at the end of the traveling direction of the vehicle can be set as the time of leaving the communication area vehicle.

  As shown in FIG. 6, the fluctuation patterns of the measured values of the received radio wave intensity of the radio waves from the vehicle-mounted devices 21-1 to 21-3 are the same fluctuation patterns at regular intervals.

  As described above, when the control device 13 can confirm the variation pattern of the measured values of the received radio wave intensity at the same level in the installation order in the traveling direction of the vehicle-mounted devices 21-1 to 21-3, the reception transition of the radio wave intensity is It is determined that the vehicle 51 has passed the gate.

  On the other hand, when the reflected wave is captured by the antenna unit 11, as illustrated in FIG. 7, a fluctuation waveform different from the fluctuation pattern of the received radio wave intensity of the plurality of vehicle-mounted devices 21-1 to 21-3 is observed. .

  Here, the waveform of the received radio wave intensity of the reflected wave varies greatly depending on the external environment. Therefore, the control device 13 determines that the radio wave in the traveling direction of the vehicle is the radio wave from the vehicle-mounted device 21 based on the received radio wave intensity of the fluctuation pattern, the measurement time of the fluctuation pattern, and the continuity of the same fluctuation pattern. The other radio waves are determined to be reflected waves.

  For example, in FIG. 7, it is assumed that the reflected wave (A) of the vehicle-mounted device 21-1 is a waveform of the received radio wave intensity of the reflected wave of the radio wave of the vehicle-mounted device 21-1.

  Unlike the radio wave from the vehicle-mounted device 21, the reflected wave is not captured by the antenna unit 11 as a straight wave. The reflected wave is reflected by some reflector and then received by the antenna unit 11. Therefore, because of the distance attenuation, the measured value of the received radio wave intensity of the reflected wave is smaller than the measured value of the vehicle-mounted devices 21-1 to 21-3, and the measurement period of the received radio wave intensity is also shortened. .

  In addition, there are irregularities such as a reflector that reflects radio waves (for example, the surface of a gate, the hood of a vehicle, etc.). Therefore, the pattern of the received radio wave intensity of the reflected wave has a waveform disturbance such as distortion with respect to the fluctuation pattern of the received radio wave intensity of the vehicle-mounted device 21.

  Therefore, the waveform of the received radio wave intensity of the reflected wave is greatly different from the fluctuation pattern of the received radio wave intensity of the radio wave of the vehicle-mounted device 21, and the control device 13 determines this greatly different waveform as the reflected wave.

  Moreover, in FIG. 7, the onboard equipment 21-3 reflected wave (B) is a reflected wave of the onboard equipment 21-3. For example, when the oncoming vehicle passes through the adjacent gate at the same time, the radio wave emitted by the vehicle-mounted device 21-3 may be reflected by the bonnet or the like of the oncoming vehicle, and the reflected wave may be captured by the antenna unit 11. In this case, for example, as illustrated in the reflected wave (B) of the vehicle-mounted device 21-3 in FIG. 7, the reflected wave is captured by the antenna unit 11 as a sudden reflected wave, and the received radio wave has a significantly short measurement period. Observed as intensity. Therefore, the control device 13 determines that the waveforms having greatly different measurement times are reflected waves.

  In addition, the control device 13 makes a determination in consideration of the continuity of a plurality of received radio wave intensity fluctuation patterns.

  For example, FIG. 7 illustrates a case where the received radio wave intensity of the reflected wave of the radio wave of the vehicle-mounted device 21-2 is not measured. The case where the received radio wave intensity of the reflected wave is not measured is, for example, when there is no reflecting object at that time and the radio wave is not reflected, or when the reflection angle is not toward the antenna unit 11, but the reflected radio wave is reflected. There are cases where the strength is weak. In such a case, a measurement value of the received radio wave intensity of the reflected wave cannot be obtained, and a continuous fluctuation pattern is obtained at regular intervals like the original fluctuation pattern of the received radio wave intensity of the plurality of in-vehicle devices 21. I can't. In this way, the control device 13 determines the reflected wave in consideration of the continuity of a plurality of fluctuation patterns of the received radio wave intensity.

  As described above, the control device 13 obtains the variation pattern of the measured value of the received radio wave intensity of each onboard equipment identification information based on the measured value of the received radio wave intensity from the wireless device 12. And the thing which the fluctuation pattern of the same reception radio wave intensity appears in a fixed time interval is specified as the thing of the onboard equipment 21-1 to 21-3 of the vehicle 51 which passes a gate.

  On the other hand, the control device 13 determines that the other fluctuation waveform of the received radio wave intensity is that of the reflected wave.

  Thereafter, the control device 13 acquires vehicle identification information included in the received radio signal, and performs predetermined gate management control using the vehicle identification information.

(A-3) Effect of the First Embodiment As described above, according to the first embodiment, when receiving radio waves from the radio device of the adjacent gate, the reflected wave is out of directivity. By performing detection detection using a radio wave reception method that considers approach from the traveling direction, erroneous detection due to reflected waves can be eliminated.

  Also, according to the first embodiment, unlike the conventional method, it is not necessary to separately provide a loop coil, a sensor, or the like, so that operation and accuracy do not depend on the sensor.

  Furthermore, according to the first embodiment, it is not necessary to perform installation work, and the construction period is shortened / the operation during construction is not affected. For example, cement mills and mines have extra large sizes, unlike trucks that run on ordinary roads, and often use dedicated vehicles on the premises. Therefore, it is possible to secure a space for installing a plurality of on-vehicle devices, and since the on-vehicle devices are very inexpensive, there is little resistance to installing a plurality of on-vehicle devices.

(B) Second Embodiment Next, a second embodiment of the road-vehicle communication system, the roadside communication control device, and the roadside communication control program of the present invention will be described with reference to the drawings.

  The second embodiment is different in the field to which the present invention is applied, and can be realized with the same configuration and operation as the first embodiment.

  FIG. 9 is an explanatory diagram illustrating a configuration image of the road-to-vehicle communication system according to the second embodiment.

  For example, a factory of a large-scale manufacturing industry is very large, and when performing control of a traffic light, location management, etc. even on a premises, DSRC technology may be used to acquire information from an on-vehicle device.

  Conventionally, a road on a campus is about the same size as a general road, and a reflected wave of a radio wave of DSRC technology installed in one side lane may enter the opposite lane. Even if it is not a reflected wave, if the road is narrow, radio waves in the opposite lane may enter. In this case, it is possible to avoid the invasion of radio waves into the opposite lane by reducing the radio field intensity, but the main line detection rate may be deteriorated by reducing the radio field intensity too much.

  On the other hand, for example, in order to prevent radio waves from entering the opposite lane, it may be possible to install a shielding plate or a sensor as in the conventional technology, but in that case the installation cost increases. And the impact of operations are issues.

  Accordingly, in the second embodiment, as illustrated in FIG. 8, since detection is determined in consideration of the traveling direction of the vehicle, it is possible to avoid erroneous detection due to intrusion of radio waves in the opposite lane.

(C) Other Embodiments In the above-described first and second embodiments, the case where the present invention is applied to the gate management system is illustrated. However, the present invention is not limited to the gate management system. The present invention can be widely applied to systems that need to detect a target radio wave without detecting a reflected wave or a radio wave used in other communications. For example, the present invention can be applied to a vehicle entrance / exit system in a parking lot, a vehicle entrance detection system on a highway, and the like.

DESCRIPTION OF SYMBOLS 1 ... Road-to-vehicle communication system, 11 ... Antenna part,
12 ... Radio,
121: Transmission / reception unit, 122 ... Reception strength measurement unit, 123 ... Information detection unit,
124: Detection information transmission unit,
13 ... Control device,
131 ... Detection information acquisition unit, 132 ... Received intensity fluctuation analysis unit,
133 ... Vehicle identification information specifying unit, 134 ... Gate management control unit,
51 ... Vehicle, 21-1 to 21-3 ... On-vehicle device.

Claims (4)

Antenna means;
A plurality of in-vehicle devices that are provided in a vehicle and that transmit radio waves including at least on-vehicle device identification information when receiving radio waves from the antenna means;
A received radio wave intensity measuring means for detecting the in-vehicle device identification information included in the radio wave signal captured by the antenna means and measuring the received radio wave intensity of the radio wave;
Based on the measurement value of the received radio wave intensity of each OBE identification information measured by the received radio wave intensity measuring means, a temporal variation pattern of the received radio wave intensity of each OBE identification information is obtained, and each of the OBE identification information A road-to-vehicle communication system comprising: a radio wave identification unit that identifies a target radio wave based on a temporal fluctuation pattern of received radio wave intensity. The plurality of vehicle-mounted devices are arranged along the traveling direction of the vehicle,
When the radio wave specifying means indicates that the time variation pattern of the received radio wave intensity of the plurality of in-vehicle device identification information shows a similar change with a predetermined time difference as the vehicle progresses, the plurality of on-vehicle devices mounted on the vehicle. 2. The road-to-vehicle communication system according to claim 1, wherein: the road-to-vehicle communication system according to claim 1 is determined to be a radio wave from the vehicle and a fluctuation pattern other than that is determined to be a reflected wave. A roadside communication control device that detects a target radio wave based on radio waves from a plurality of vehicle-mounted devices provided in a vehicle,
Antenna means;
A received radio wave intensity measuring unit that detects the vehicle-mounted device identification information included in the radio wave signal captured by the antenna unit and measures the received radio wave intensity of the radio wave;
Based on the measurement value of the received radio wave intensity of each OBE identification information measured by the received radio wave intensity measuring means, a temporal variation pattern of the received radio wave intensity of each OBE identification information is obtained, and each of the OBE identification information A roadside communication control device comprising: radio wave specifying means for specifying a target radio wave based on a temporal fluctuation pattern of received radio wave intensity. A roadside communication control program for detecting a target radio wave based on radio waves from a plurality of on-vehicle devices provided in a vehicle,
Computer
Received radio wave intensity measuring means for detecting the vehicle-mounted device identification information included in the radio wave signal captured by the antenna means and measuring the received radio wave intensity of the radio wave,
Based on the measurement value of the received radio wave intensity of each OBE identification information measured by the received radio wave intensity measuring means, a temporal variation pattern of the received radio wave intensity of each OBE identification information is obtained, and each of the OBE identification information A roadside communication control program that functions as a radio wave identification unit that identifies a target radio wave based on a temporal fluctuation pattern of received radio wave intensity.

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