JP2002109591A - Radiocommunication system, mobile unit, and stationary radio equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve an exclusive narrow area communication system capable of securely communicating only within a desired communication area regardless of an installed location of a vehicle-mounted unit dependent on a surrounding radio waves environment and a type of a car. SOLUTION: An indication marker for transmitting ON signal of the vehicle- mounted unit to a vehicle is installed nearly this side part of a communication area. The signal is transmitted to the vehicle-mounted unit through a vehicle- mounted marker mounted on the vehicle to start operation of the vehicle- mounted unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dedicated wireless communication device for securely communicating between a moving object and a fixed wireless device (fixed wireless device) in a predetermined limited area such as a road or a parking lot. The present invention relates to a wireless communication system, a mobile unit, and a fixed wireless communication device with respect to short-range communication.

[0002]

2. Description of the Related Art Nonstop automatic toll collection (hereinafter referred to as ETC)
) Systems and parking fee collection systems. For example, in an ETC system, an antenna (fixed wireless communication device) installed above a lane at a tollgate
Necessary information is wirelessly communicated between the vehicle and an ETC-compatible vehicle-mounted device (mobile body) mounted on the vehicle, and a toll charging process is automatically performed. Therefore, the vehicle can pass through the tollgate without stopping, and congestion at the tollgate on the toll road can be eliminated. Further, in the parking fee collection system, similarly, necessary information is wirelessly communicated between an antenna (fixed wireless communication device) provided above the entrance of the parking lot and the vehicle-mounted device (mobile body), and the parking fee is collected. The billing process is performed automatically. However, vehicles running on toll roads are not equipped with non-E
Since TC vehicles are also included, at tollgates, ETC vehicles and non-ETC vehicles are identified.
The vehicle is allowed to pass through the C-lane and bills automatically. In addition, for non-ETC vehicles, the gate is closed and the passage through the ETC lane is prohibited. carry out. FIG. 11 is an external view showing an example applied to an ETC system as an example of a conventional dedicated narrow-area communication system. This is disclosed in JP-A-10-11625.
This is an example described in Japanese Patent Publication No.

In the drawing, reference numerals 1a and 1b denote lanes and 2a to 2a.
c is the lane separation zone, 3a is the traveling direction of the lane 1a, 4 is a vehicle entering the tollgate area of the lane 1a, 5 is an onboard device mounted on the vehicle 4, 6a and 6b are the vehicles 4
Are provided at predetermined intervals in the traveling direction 3a of the vehicle, and the gate-shaped supports 7c and 7d provided so as to straddle the lane 1a are roadside antennas 8a and 8b attached to the upper portions of the supports 6a and 6b, respectively. Is the above roadside antenna 7
Beams 9c and 9d radiated from lanes c and 7d toward the lower lane 1a are the roadside antennas 7c and 7d, respectively.
Communication areas 10a and 10b correspond to the communication areas 9 respectively.
c, gray zones around 9d, 14c and 14
d, 14e and 14f are vehicle detection sensors provided in pairs on the lane divider 2a, respectively, and defining the communication areas 9c and 9d.

Next, the operation will be described. When the vehicle 4 reaches the communication area 9c and the front end of the vehicle 4 is detected by the vehicle detection sensor 14c, the roadside antenna 7c starts communication for toll collection with the vehicle-mounted device 5, and then the vehicle at the subsequent stage. When the detection sensor 14d detects the leading end of the vehicle 4, the communication is stopped. That is, if the traveling vehicle 4 is an ETC vehicle equipped with the vehicle-mounted device 5, the roadside antenna 7
Information necessary for non-stop toll collection between the toll booth and the ETC vehicle is transmitted and received via c. Thereafter, when the vehicle 4 advances and reaches the next communication area 9d, information is exchanged between the tollgate and the vehicle 4 via the roadside antenna 7d. The information exchanged in each of the two communication areas 9c and 9d is different. For example, in the first communication area 9c, confirmation of the vehicle type is performed, and in the latter communication area 9d, exchange of information is different, such as deduction of a fee. Is performed.

Here, in FIG. 11, communication areas 9c, 9
The highlighted part of the white part d is the roadside antenna 7
Communication may be made in the area irradiated with the beams 8a and 8b of c and 7d depending on the condition of the vehicle-mounted device 5 (reception sensitivity and the like) around the communication areas 9c and 9d and the surrounding radio wave environment such as the toll booth roof. Gray zones of uncertainty 10a, 10
This is because b exists. Accordingly, the vehicle-side sensors 7c and 7d detect the front-end portions of the vehicle 4 by the vehicle detection sensors 14c to 14f so that the information is transmitted and received in the communication areas 9c and 9d where the information can be transmitted and received most accurately. The start and end of the communication are controlled between.

[0006]

Since the conventional dedicated short-range communication system is configured as described above, the on-vehicle device is not operated due to a partial increase in the electric field intensity level due to the surrounding radio wave environment such as a tollgate roof. There is a problem that it is not possible to send and receive normal information in the legitimate communication area,
There was a problem that the vehicle-mounted device would react in the adjacent lane. For example, when the vehicle detection sensor 14c detects the leading end of the vehicle 4 and transmits information of starting communication from the roadside antenna 7c to the vehicle 4, the vehicle 4 is a non-ETC vehicle and the following vehicle is It is assumed that the vehicle will be an ETC vehicle. In this case, if a non-regular communicable area is formed in front of the detection sensor 14c due to a partial increase in the electric field strength level of the beam 8a of the roadside antenna 7c outside the communication area 9c, the non-regular communicable area is formed. When a subsequent ETC vehicle enters the communicable area, communication is established between the subsequent ETC vehicle and the roadside antenna 7c, and information is exchanged in an irregular communication area. At the same time, the leading non-ETC vehicle may be erroneously recognized as an ETC vehicle, and may pass without being charged for the toll of the non-ETC vehicle.

Further, in order to avoid such a partial increase in the electric field intensity level, a radio wave absorber must be provided on the surrounding reflecting structure. There were also problems such as enormous costs for reduction.

Further, in actuality, the positional relationship (distance) between the front end of the vehicle and the vehicle-mounted device may differ depending on the type of vehicle, or the vehicle may run at low speed (or congestion). Even if a time delay is applied (even if the OBE is pulled sufficiently into the communication area before attempting to communicate with the OBE), the OBE still has uncertainty depending on the type and speed of the vehicle with the OBE. Since it may occur in a certain gray zone, there is also a problem that reliable communication cannot be established depending on the situation.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and ensures normal communication regardless of the surrounding radio wave environment (no need to completely take measures to reduce reflected waves). It is intended to realize a dedicated narrow-area communication system that can be performed. It is another object of the present invention to realize a dedicated narrow-area communication system capable of reliably performing communication only within a desired communication area regardless of the installation position of the vehicle-mounted device depending on a vehicle type.

[0010]

A wireless communication system according to a first aspect of the present invention is provided at a predetermined position in a communication area of an antenna in a wireless communication system for performing wireless communication between an antenna and a mobile body. An instruction marker for sending an ON signal to a moving object passing in the vicinity, and a moving object-side marker provided on the moving object and instructing the start of communication between the wireless device and the antenna of the moving object in response to receiving the ON signal It is provided with.

[0011] In a wireless communication system according to a second aspect of the present invention, in the first aspect, the moving object is a vehicle, the antenna is a roadside antenna installed on a road, and the indication marker is a roadside antenna of the roadside antenna. The vehicle-side marker installed on the vehicle approach side in the communication area operates the vehicle-mounted device that communicates with the roadside antenna in response to receiving an ON signal from the instruction marker.

[0012] In a wireless communication system according to a third invention, in the second invention, the indication marker transmits a frequency selection signal together with the ON signal, and the moving object-side marker responds to the frequency selection signal from the indication marker. To set the communication frequency of the vehicle-mounted device.

A wireless communication system according to a fourth aspect of the present invention is the radio communication system according to the second or third aspect, wherein a second indication marker for issuing an on-vehicle device OFF signal is provided near an end near the roadside antenna in a communication area of the antenna. It was installed.

According to a fifth aspect of the present invention, there is provided the radio communication system according to the second to fourth aspects, wherein one or both of the pointing markers are installed near an end of the communication area on a vehicle approach side or a roadside antenna side. A vehicle detection sensor is provided immediately before the operation, and the operation of the pointing marker is controlled based on a detection signal of the vehicle detection sensor.

A sixth aspect of the present invention is the radio communication system according to the second to fifth aspects, wherein after the onboard unit receives the control signal issued from the instruction marker, the onboard unit transmits the status signal for notifying reception completion or the like to the onboard unit. The indicator emits the indication marker via the in-vehicle marker and controls the operation of the indication marker based on the status signal.

A mobile unit according to a seventh aspect of the present invention is a mobile unit that performs wireless communication with an antenna. The mobile unit is turned on by a pointing marker provided at a predetermined position in a communication area of the antenna.
It is provided with a moving object side marker that starts a communication operation with an antenna in response to signal reception.

An eighth aspect of the present invention is the mobile object according to the seventh aspect, wherein the mobile object is a vehicle equipped with an on-vehicle device,
The moving body-side marker is installed below the vehicle-mounted device mounting position on the lower surface of the vehicle.

A fixed wireless device according to a ninth aspect of the present invention is a fixed wireless device for performing wireless communication with a mobile object in a predetermined communication area, provided at a predetermined position in the communication area.
An instruction marker for sending an ON signal for instructing the start of communication operation to a moving object passing near the predetermined position is provided.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a perspective view showing a dedicated narrow-area communication system according to the first embodiment. FIG. 1A shows a case of one lane, and FIG. 1B shows a case of two lanes. FIG. 2 is an electric field strength characteristic diagram for explaining the operation, FIG. 3 is an operation conceptual diagram for explaining the control contents,
FIG. 4 is a diagram illustrating a positional relationship between the directivity of the pointing marker 11 and the on-vehicle marker 12.

In the figure, reference numeral 11 denotes an indication marker which is installed on the lanes 1 and 1a near the end of the communication area 9 on the near side (vehicle entry side) and which transmits a radio wave or a magnetic signal.
(12a to 12d) are in-vehicle markers mounted on the vehicle 4 (4a to 4d) so as to substantially face the indicating markers 11, respectively, and 13 is a reflecting structure such as a toll booth placed near the roadside antenna 7. And 1 to 10 are exactly the same as those of the conventional dedicated narrow-area communication system. In the figure, the pointing marker 11 is installed near the end on the vehicle approach side in the communication area 9 of the roadside antenna 7 and substantially at the center thereof.

Next, the operation of the dedicated narrow area communication system will be described. As shown in FIG. 3, the vehicle 4 is equipped with a vehicle-mounted device 5 for communicating with the roadside antenna 7, and the vehicle-mounted device 5 is also connected to a vehicle-mounted marker 12. The in-vehicle marker 12 is disposed substantially on the vertical line of the installation position of the in-vehicle device 5 in the vehicle 4, but is preferably mounted on the lower surface of the vehicle 4 directly below the in-vehicle device 5. The on-vehicle marker 12 receives a signal (on-vehicle device ON signal) transmitted from the instruction marker 11 installed on the lane 1 and transmits this signal to the on-vehicle device 5. Next, the vehicle-mounted device 5 that has received this signal operates so as to be in a standby state in which communication with the roadside antenna 7 is possible. First, a series of operations will be described with reference to FIG. The vehicle 4a enters the lane 1a in the traveling direction 3a. At this time, the operation of the vehicle-mounted device 5a is always
OFF state. A radio signal for calling the vehicle-mounted device 5 is transmitted from the roadside antenna 7. Pointer marker 1
The on-board unit ON signal is always transmitted from 1 and the vehicle 4a
When the vehicle approaches the indication marker 11, the vehicle-mounted marker 1
2a receives the vehicle-mounted device ON signal issued from the instruction marker 11. At this time, the in-vehicle marker 12 is moved in the vehicle width direction due to a difference in vehicle width / height for each vehicle type, a variation in the mounting position of the in-vehicle marker 12 in the vehicle 4, or a variation in the vehicle passing position in the lane direction in the vehicle width direction. It passes with a certain range (pass range).

As shown in FIG. 4, the pointing marker 11 must have a directivity that covers a passing range in the vehicle width direction of the vehicle-mounted marker 12 mounted on the vehicle 4. The directivity is provided so as to cover the expected angle θ corresponding to this passing range with a half power width. Further, it is desirable to determine the beam pattern of the transmission wave of the indication marker 11 so that the leakage of the transmission wave into the adjacent lane is reduced.

Next, the vehicle-mounted device 5a receives the received vehicle-mounted device O
Based on the N signal (for example, when the electric field strength of the on-vehicle device ON signal is equal to or more than a predetermined value), a standby state is established to start communication with the roadside antenna 7. At this time, since the on-vehicle device 5a exists in the communication area 9 where the electric field strength level is stable, it operates to normally communicate with the roadside antenna 7. That is, the traveling vehicle 4a is an ETC equipped with the vehicle-mounted device 5a.
In the case of a car, the vehicle-mounted device 5a that has received the call from the roadside antenna 7 outputs a vehicle-mounted device ID for identifying the vehicle-mounted device, and a computer at a tollgate (not shown) connected to the roadside antenna 7 ), The legitimacy of this vehicle-mounted device ID (communication for toll collection may be performed) is confirmed, and communication between the vehicle-mounted device 5a and the toll booth is established (linked), and the toll booth and the ETC vehicle are established. Information necessary for collecting tolls in a non-stop state is transmitted and received between them.

Further, as shown in FIG. 1B, a case will be described in which a radio wave radiated from the roadside antenna 7 is multiply propagated between the reflecting structure 13 such as a tollgate roof and the road surface. In this case, the gray zone 10 extends not only to the lane 1a, which is the own lane, but also to the lane 1b, which is an adjacent lane. As shown in FIG. Inconveniences such as a rise above the minimum reception level of However, according to this embodiment, when the lane 1b is not the ETC lane, the vehicle-mounted device 5b of the vehicle 4b traveling in the lane 1b is in the OFF state, and the vehicle-mounted device 5b may erroneously communicate with the roadside antenna 7 on the lane 1a. There is nothing. Further, even when the electric field strength level partially increases before the communication area 9 in the lane 1a, the vehicle-mounted device 5a temporarily reacts, and the communication is interrupted due to a subsequent drop in the electric field strength and a timeout occurs. (Communication error) and when the vehicle-mounted device 5a returns again, it is possible to avoid a situation in which normal communication cannot be performed due to the vehicle 4a having passed through the communication area 9. Even if the ETC vehicle is approaching from behind a non-ETC vehicle passing through the communication area 9, the vehicle is not mounted until the vehicle-mounted device 5 b of the subsequent ETC vehicle passes over the indication marker 11. It does not receive the device ON signal and therefore does not erroneously communicate with the following vehicle. Further, the in-vehicle marker 12
Is provided on the vertical line of the vehicle-mounted device 5, so that the communication start position does not deviate due to the variation of the vehicle length of the vehicle 4 and the installation position of the vehicle-mounted device 5 in the vehicle 4. Communication can be started at a stable position according to the approach.

Although the operation example in the case where one roadside antenna 7 is placed in the lane 1a has been described above, the same operation is performed even when the second roadside antenna 7 is placed at a certain distance. I do. That is, it is possible to exchange different information such as confirmation of a vehicle type in the first communication area 9 and deduction of a fee in the latter communication area 9. The invention is not limited to this, and a plurality of roadside antennas 7 may be cascaded. Further, in response to the reception of the vehicle-mounted device ON signal at the vehicle-mounted marker 12, the vehicle-mounted device 5 sends an interrogation signal to the roadside antenna 7, and in response to this, the roadside antenna 7 starts outputting a transmission wave. Thus, communication between the on-vehicle device 5 and the roadside antenna 7 may be started. In this case, it is not necessary to always transmit a transmission wave from the roadside antenna 7, and it is sufficient to transmit a transmission wave for communicating with the vehicle-mounted device 5 only when the vehicle-mounted device 5 approaches. Even less.

As described above, in this embodiment, the vehicle-mounted device
Since the ON signal is transmitted from the indicator marker to the vehicle-mounted device via the vehicle-mounted marker to start the operation of the vehicle-mounted device, the vehicle-mounted device is activated by a partial increase in the electric field strength level due to the surrounding radio wave environment. An effect is obtained that normal information can be transmitted and received in the regular communication area without temporarily reacting in the own lane and the adjacent lane. In addition, since it is not necessary to install an expensive radio wave absorber on the surrounding reflection structure in order to avoid a partial increase in the electric field strength level, there is no need to spend enormous costs on reducing reflected waves, The effect that cost can be suppressed is obtained. Furthermore, the distance difference between the tip of the vehicle and the vehicle-mounted device depending on the vehicle type, the time difference between the detection time of the vehicle detection sensor depending on the running state of the vehicle and the time until the vehicle-mounted device actually reaches the communication area, etc. are considered. There is no need to perform this operation (in other words, regardless of the presence or absence of the gray zone), and an effect of realizing a dedicated narrow-area communication system capable of exchanging information with the roadside antenna only in a desired communication area is obtained.

Embodiment 2 FIG. FIG. 5 is an operation conceptual diagram of the dedicated narrow-area communication system according to the second embodiment of the present invention.
FIG. 6 is a perspective view for explaining the operation. In the second embodiment, a control signal composed of a frequency number is issued from the indication marker 11 in addition to the vehicle-mounted device ON signal.
The vehicle-mounted device 5 communicates with the roadside antenna 7 at a frequency corresponding to the frequency number. For example, two frequencies (f
1, 2 in the case of a control signal having a frequency number of f2)
A repetitive signal with a data length of bits (bit interval w seconds,
(Signal repetition period T seconds) is transmitted and the first bit is ON
/ OFF signal, the second bit is assigned to the frequency number, if the first bit is 0, it is OFF, if it is 1, and it is ON,
If the first signal of the first bit is 1 and the signal of the second bit received after w seconds is 0, the frequency is f1, and the first signal of the first bit is 1 and the second bit received after w seconds. If the signal is 1, a control signal defined as the frequency f2 is transmitted from the pointing marker 11. The perspective view showing the dedicated narrow-area communication system according to the second embodiment is the same as FIG. 1, and the electric field strength characteristic diagram for explaining the operation is the same as FIG.

As described above, according to the dedicated narrow-area communication system according to the second embodiment, in addition to the vehicle-mounted device ON signal, a control signal having a frequency number is mounted on the vehicle 4 from the instruction marker 11. Onboard equipment 5 via 12
And the vehicle-mounted device 5 is placed in a standby state in which the vehicle-mounted device 5 can communicate with the vehicle-mounted device ON signal, and communicates with the roadside antenna 7 at a frequency corresponding to the frequency number. ET similar to lane 1a of own lane
Even in the case of the C lane, the on-vehicle devices 5a and 5b existing in the different lanes 1a and 1b can be set in the standby state at the different frequencies f1 and f2 assigned to the communication areas 9a and 9b, respectively. Even in the case of being adjacent, erroneous communication with the adjacent roadside antenna 7 can be avoided. Communication with the roadside antenna 7 in the own lane can be realized by the same principle as in the first embodiment.

In this embodiment, the vehicle-mounted device communicates with the roadside antenna at a predetermined frequency corresponding to the frequency number by transmitting the vehicle-mounted device ON signal and the frequency number from the indication marker to the vehicle-mounted device via the vehicle-mounted marker. Therefore, even when the adjacent lane is the same ETC lane as the own lane, each on-vehicle device existing in a different lane can be in a standby state at a different frequency assigned to each communication area, and The effect of avoiding erroneous communication with the roadside antenna in the adjacent lane can be obtained.

Embodiment 3 FIG. 7 is an external view of a dedicated narrow-area communication system according to Embodiment 3 of the present invention.
FIG. 4 is an operation conceptual diagram for explaining control contents. In the third embodiment, an in-vehicle device ON signal or an instruction marker 11d that emits a frequency number in addition to this signal is installed on the lane 1 near the end near the near side (vehicle approach side) of the communication area 9, and Indication marker 11c for issuing OBE OFF signal
Is installed substantially near the end of the communication area 9 on the roadside antenna 7 side. The electric field strength characteristic diagram for explaining the operation of the dedicated narrow-area communication system according to the third embodiment is the same as that in FIG. An operation conceptual diagram for explaining the control contents of the instruction marker 11d is the same as that in FIG. 3 or FIG.

As described above, according to the dedicated narrow-area communication system according to the third embodiment, the indication marker 11c for issuing the on-vehicle device OFF signal is installed substantially near the end of the communication area 9 on the roadside antenna 7 side. However, since the vehicle-mounted device OFF signal is received by the vehicle-mounted marker 12 mounted on the vehicle 4 and transmitted to the vehicle-mounted device 5, after the vehicle 4 passes through the communication area 9, the operation of the vehicle-mounted device 5 must be surely turned off. Can be. Therefore, even if there is a gray zone 10 after passing through the communication area 9 or an area where the electric field strength level partially exceeds the minimum reception level of the vehicle-mounted device 5, the vehicle-mounted device 5 reacts to the roadside antenna 7. Can be reliably avoided. The communication with the roadside antenna 7 in the own lane is described in the first or second embodiment.
Can be realized by the same principle as any of the above.

According to this embodiment, since the indication marker for issuing the on-vehicle device OFF signal is installed substantially near the end on the roadside antenna side of the communication region, the operation of the on-vehicle device immediately after the vehicle passes through the communication region. Even if there is a gray zone after passing through the communication area or an area where the electric field strength level partially exceeds the minimum reception level of the OBE, the OBE does not respond to the roadside antenna outside the communication area The effect of realizing a narrow area communication system is obtained.

Embodiment 4 FIG. 9 is an external view of a dedicated narrow-area communication system according to Embodiment 4 of the present invention. In the fourth embodiment, the pointing marker 1 installed near the communication area 9 (on the vehicle approach side) and near the end on the roadside antenna 7 side
Immediately before 1a, 11b, vehicle detection sensors 14a, 14b
The indication markers 11a, 1b, 1b, and 1b are provided based on detection signals 15a, 15b of the vehicle detection sensors 14a, 14b.
1b is controlled. The electric field strength characteristic diagram for explaining the operation of the dedicated narrow area communication system in the fourth embodiment is the same as that of FIG. 2, and the operation conceptual diagram for explaining the control contents is shown in FIG. 3 or FIG.
And FIG.

As described above, according to the dedicated narrow-area communication system according to the fourth embodiment, the indicator marker 11a installed near the communication area 9 (on the vehicle approach side) and near the end on the roadside antenna 7 side. , 11b, the vehicle detection sensors 14a, 14b are provided.
Are detected by the vehicle detection sensors 14a, 14b, the detection signals 15a, 15b are indicated by the indication markers 11a, 11b.
b. For this reason, the instruction markers 11a and 11b are turned off until the following vehicles 4a and 4b approach.
Although not shown, the detection signals 15a, 1
The operation is turned off by a timer or the like when a certain time has elapsed after the indication markers 11a and 11b are triggered in 5b, so that only when the target vehicle 4 is in the vicinity of the indication marker 11, the indication marker 11 is replaced with the on-vehicle marker. 12 can transmit a control signal. Therefore, the communication time between the pointing marker 11 and the on-vehicle marker 12 can be limited, and unexpected transmission of information from the pointing marker 11 to other than the target vehicle 4 due to the constantly changing surrounding radio wave environment on the road can be avoided. Also, by mounting the indicating marker 11 near the road surface of the lane 1 and mounting the in-vehicle marker 12 on the lower surface of the vehicle 4, a leakage signal of a signal transmitted from the indicating marker 11 is blocked by the vehicle 4. It is possible to further prevent unexpected transmission of information from the instruction marker 11 to other locations. Communication with the roadside antenna 7 in the own lane can be realized by the same principle as in any one of the first to third embodiments.

Here, in the fourth embodiment, the vehicle detection sensor is used for the case where the pointing marker 11 is installed both on the near side (vehicle approach side) of the communication area 9 and near the end on the roadside antenna 7 side. 14, the communication area 9
In the case where the indicator marker 11 is installed either on the near side of the vehicle (on the vehicle approach side) or near the end on the roadside antenna 7 side, the vehicle is detected at one of the vicinity of the front and rear ends in combination with the indicator marker 11. Sensor 14 may be provided.

According to this embodiment, a vehicle detection sensor is provided immediately before one or both of the indication markers installed on the near side (vehicle entry side) of the communication area or near the end on the roadside antenna side. However, since the operation of the pointing marker is controlled based on this detection signal, the communication time between the pointing marker and the on-vehicle marker can be limited, and unexpected changes to the vehicle other than the target vehicle due to the constantly changing surrounding radio wave environment on the road. An effect is obtained that information transmission from the pointing marker can be avoided.

Embodiment 5 FIG. 10 is an operation conceptual diagram of the dedicated narrow-area communication system according to the fifth embodiment of the present invention. In the fifth embodiment, after the vehicle-mounted device 5 receives the control signal issued from the instruction marker 11, the vehicle-mounted device 5 transmits a status signal notifying the completion of reception and the like from the vehicle-mounted device 12.
And sends the control signal to the indication marker 11 based on the status signal, thereby turning off the operation of the indication marker 11 and retransmitting the control signal. The perspective view showing the dedicated narrow-area communication system in the fifth embodiment is the same as FIG. 1 or FIG. 6, and the external view is the same as FIG. 7 or FIG. An electric field strength characteristic diagram for explaining the operation is the same as that in FIG.

As described above, according to the dedicated narrow-area communication system according to the fifth embodiment, the status signal is transmitted from the vehicle-mounted device 5 via the vehicle-mounted marker 12 to the indication marker 11.
To turn off the operation of the indicator marker 11 or resend the control signal, so that reliable information transmission between the vehicle-mounted device 5, the indicator marker 11, and the vehicle-mounted marker 12 can be realized. The operation of the marker 11 can be controlled.
Therefore, the operation of the instruction marker 11 is determined by the timer or the like.
Since there is no need to perform the F, it is possible to avoid untransmitted information and unexpected information transmission from the indication marker 11 to other than the target vehicle 4 in any traffic condition (congestion, low-speed running, surrounding radio wave environment, etc.) Narrow area communication can be realized. FIG.
The operation of the pointing marker 11b in the vehicle detection sensor 14b can be turned off by a command from the vehicle-mounted device 5 so that the pointing marker 11b is turned on in response to a detection signal 15a from the vehicle detecting sensor 14a.
Becomes unnecessary. Communication with the roadside antenna 7 in the own lane can be realized by the same principle as in any one of the first to fourth embodiments.

According to this embodiment, after the vehicle-mounted device receives the control signal transmitted from the instruction marker, the vehicle-mounted device issues a status signal notifying the completion of reception and the like to the instruction marker via the vehicle-mounted marker. In order to control the operation of the marker (OFF or resend the control signal), information is not transmitted in any traffic condition (congestion, low-speed driving, surrounding radio wave environment, etc.) and information from unexpected indication markers other than the target vehicle The effect of realizing a dedicated narrow-area communication system capable of avoiding transmission is obtained. Further, since the operation of the pointing marker can be turned off by a command from the vehicle-mounted device, a vehicle detection sensor is not required, and the effects of reducing cost and improving reliability can be obtained.

Here, the communication area 9 in the first to fifth embodiments is the lane 1a (own lane) or the lane 1b.
Although they are arranged in (adjacent lanes), a plurality of communication areas 9 may be arranged on one lane 1 or on each lane 1 arranged in parallel.

The pointing marker 11 in the first to fifth embodiments is installed on the road surface on the lane 1, but is not limited to this and may be installed at any place where the vehicle 4 such as the lane separation zone 2 can be seen. Is also good.

The pointing marker 11 and the on-vehicle marker 12 in the above-described first to fifth embodiments may use any medium such as radio waves or infrared rays as signal transmission means.

[0043]

According to the first, seventh to ninth aspects of the present invention, an ON signal is transmitted from an instruction marker to a marker on a moving object side to start operation of a radio device of the moving object, thereby enabling communication in a predetermined communication area. The effect that normal information can be transmitted and received is obtained.

According to the second aspect of the present invention, the vehicle-mounted device does not temporarily react in the own lane and the adjacent lane due to a partial increase in the electric field intensity level due to the surrounding radio wave environment, and the vehicle-mounted device is connected to the roadside. It is possible to exchange information with the roadside antenna only in a desired communication area with the antenna.

According to the third invention, the vehicle-mounted device transmits the frequency selection signal from the indication marker to the vehicle-mounted device via the vehicle-mounted marker, so that the vehicle-mounted device can communicate with the roadside antenna at a predetermined frequency corresponding to the frequency selection signal. It is possible to communicate, even if the adjacent lane is the same ETC lane as the own lane, each on-board unit existing in a different lane can be in a standby state at a different frequency assigned to each communication area, It is possible to prevent the vehicle-mounted device from erroneously communicating with the roadside antenna in the adjacent lane.

According to the fourth aspect of the present invention, since the indication marker for issuing the on-vehicle device OFF signal is provided substantially near the end on the roadside antenna side of the communication area, the on-vehicle device is activated immediately after the vehicle passes through the communication area. Operation can be reliably turned off.

According to the fifth aspect of the present invention, the vehicle detection sensor is provided immediately before one or both of the indication markers installed on the near side (vehicle approach side) of the communication area or near the end on the roadside antenna side. Since the operation of the pointing marker is controlled based on the detection signal, the communication time between the pointing marker and the on-vehicle marker can be limited.

According to the sixth invention, after the vehicle-mounted device receives the control signal transmitted from the pointing marker, the vehicle-mounted device issues a status signal notifying the completion of reception to the pointing marker via the vehicle-mounted marker. Thus, the operation of the pointing marker can be controlled.

[Brief description of the drawings]

FIG. 1 is a perspective view showing Embodiment 1 of a dedicated narrow-area communication system according to the present invention.

FIG. 2 is an electric field strength characteristic diagram for explaining an operation.

FIG. 3 is an operation conceptual diagram for describing control contents of an instruction marker and a vehicle-mounted marker according to the first embodiment.

FIG. 4 is a diagram showing directivity of a pointing marker according to the first embodiment.

FIG. 5 is an operation conceptual diagram showing Embodiment 2 of the dedicated narrow-area communication system according to the present invention.

FIG. 6 is a perspective view for explaining the operation.

FIG. 7 is an external view of a dedicated narrow-area communication system according to a third embodiment of the present invention.

FIG. 8 is an operation conceptual diagram for explaining control contents.

FIG. 9 is an external view of a dedicated narrow-area communication system according to a fourth embodiment of the present invention.

FIG. 10 is an operation conceptual diagram showing Embodiment 5 of the dedicated narrow area communication system according to the present invention.

FIG. 11 is a perspective view showing a conventional dedicated narrow-area communication system.

[Explanation of symbols]

1 lane, 2 lane divider, 3 heading, 4 vehicles,
5 on-board unit, 6 support, 7 roadside antenna, 8 beam, 9 communication area, 10 gray zone, 11 indication marker, 12 on-board marker, 13 reflective structure, 14 vehicle detection sensor, 15 detection signal.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Satoshi Hamano 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term in Mitsubishi Electric Corporation (reference) 3E027 EA01 EA03 EB02 EC03 EC06 EC07 5H180 AA01 BB04 CC12 CC24 EE07 EE10 5K067 AA33 BB02 BB43 DD17 DD29 EE02 EE12 GG11 KK01

Claims (9)

[Claims] In a wireless communication system for performing wireless communication between an antenna and a moving object, an indication marker provided at a predetermined position in a communication area of the antenna and transmitting an ON signal to the moving object passing near the predetermined position. And a mobile-side marker provided on the mobile body and instructing the start of communication between the wireless device and the antenna of the mobile body in response to receiving the ON signal. 2. The vehicle according to claim 1, wherein the moving object is a vehicle, the antenna is a roadside antenna installed on a road, and the pointing marker is installed on the vehicle approach side in a communication area of the roadside antenna. The marker operates an on-vehicle device that communicates with the roadside antenna in response to reception of an ON signal from the instruction marker.
A wireless communication system as described. 3. The pointing marker transmits a frequency selection signal together with the ON signal, and the moving object-side marker sets a communication frequency of the vehicle-mounted device according to a frequency selection signal from the pointing marker. The wireless communication system according to claim 2. 4. The antenna according to claim 2, wherein a second indication marker for issuing an on-vehicle device OFF signal is disposed substantially near an end on the roadside antenna side in a communication area of the antenna.
Or the wireless communication system according to 3. 5. A vehicle detection sensor is provided immediately before one or both of the indicating markers installed near the vehicle approach side or the roadside antenna side of the communication area. 3. The operation of the pointing marker is controlled based on a detection signal.
5. The wireless communication system according to any one of claims 1 to 4. 6. The vehicle-mounted device transmits a status signal for notifying reception completion or the like to the indication marker via the vehicle-mounted marker from the vehicle-mounted device after receiving the control signal issued from the instruction marker, and The wireless communication system according to any one of claims 2 to 5, wherein the operation of the indication marker is controlled based on a status signal. 7. A mobile unit that performs wireless communication with an antenna performs a communication operation with the antenna in response to receiving an ON signal from an instruction marker provided at a predetermined position in a communication area of the antenna. A moving object comprising a moving object-side marker to be started. 8. The vehicle according to claim 7, wherein the moving body is a vehicle having a vehicle-mounted device mounted thereon, and the moving body-side marker is installed below a vehicle-mounted device mounting position on a lower surface of the vehicle. body. 9. A fixed wireless device for performing wireless communication with a moving body in a predetermined communication area, wherein the fixed wireless apparatus is provided at a predetermined position in the communication area and performs a communication operation with respect to a moving body passing near the predetermined position. A fixed wireless device comprising an instruction marker for sending an ON signal for instructing start.