JP2002312814A - Automatic toll collection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a system from being down by detecting an antenna part being abnormal in such a case and independently switching the antenna to a standby antenna. SOLUTION: Abnormality of a 1st antenna part is monitored and then even if the 1st antenna part 4a becomes abnormal, the 1st antenna part can automatically be switched to a 2nd antenna part functioning as a standby antenna, thereby continuously communicating with on-vehicle equipment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic toll collection system for automatically transferring tolls by communication between a vehicle-mounted device mounted on a vehicle and a roadside device.
l Collection System).

[0002]

2. Description of the Related Art FIG. 8 is a diagram showing a configuration of devices installed on a road side of a tollgate in ETC. In the figure, reference numeral 1 denotes a case where the circuit breaker is opened when the passing vehicle does not need to stop at the toll gate without passing through the toll gate, and when the toll vehicle stops at the toll gate and needs to pay the toll by hand to the toll collector. A transmission controller for indicating whether or not the vehicle can pass through the tollgate by closing the circuit breaker, a vehicle detector for detecting the presence or absence of a passing vehicle traveling in the tollgate, Is a roadside controller for communicating with passing vehicles and controlling devices installed on the roadside, and 4 is an antenna unit set on a gate-shaped gantry provided on a road for performing wireless communication with passing vehicles. 5 is the E that runs inside the toll booth
It shows a TC-compliant passing vehicle.

FIG. 9 shows the configuration and connection of the roadside device 3 and the antenna unit 4, 6 is an antenna for wireless communication in the antenna unit 4, and 7 is an antenna for wireless communication signals in the antenna unit 4. Transmitting / receiving section for transmitting / receiving, 10
Is a communication control unit that controls the antenna unit 4, 11 is a roadside device control unit that controls each roadside device other than the antenna, and 12 is communication information from the passing vehicle provided by the communication control unit 10 and the roadside device control unit 11. And an ETC processing unit 15 for processing location information and determining charging operation and operation of each device. Reference numeral 15 denotes a signal line connecting the transmission / reception unit 7 and the communication control unit 10.

The conventional ETC is configured as described above. When a passing vehicle passes the side of the vehicle detector 2 and the vehicle is detected, the result of the detection is transmitted from the roadside device control unit 11 to the E side.
The information is transmitted to the TC processing unit 12, and the ETC processing unit 12 instructs the communication control unit 10 to start communication, so that bidirectional communication between the vehicle-mounted device mounted on the passing vehicle and the antenna unit 4 is started. For example, from the vehicle-mounted device to the antenna unit 4, unique information for identifying the vehicle-mounted device (the vehicle-mounted device ID) and the information indicating the traffic history recorded in the vehicle-mounted device (passing through the entrance tollgate that passed earlier and on the way) The information for specifying the position of the tollgate) is transmitted, and the antenna unit 4 and the transmission / reception unit 7 receive the transmission information. ETC processing unit 12
In this, the received vehicle-mounted device ID is compared with the information of the previously permitted vehicle-mounted device ID to determine whether communication with the vehicle-mounted device is possible,
If the on-vehicle device ID is an appropriate authorized one, it instructs the communication control unit 10 to start communication with the on-vehicle device. After the communication between the roadside device and the vehicle-mounted device starts, the ET
The C processing unit 12 is based on the information indicating the traffic history of the vehicle-mounted device received by the transmission / reception unit 7, and the toll (charging information) of the vehicle corresponding to the traveling distance from the entrance tollgate to the exit tollgate.
Is calculated, and this billing information is transmitted to the vehicle-mounted device via the antenna unit 4, and the billing information is also transmitted to the central processing center. The vehicle-mounted device displays the toll based on the transmitted billing information, and the central processing center performs a post-payment deduction and payment of the toll from the bank account of the user who owns the vehicle-mounted device based on the billing information. As a result, the vehicle can pass through the tollgate without stopping, and congestion at the tollgate such as an expressway or a toll road can be reduced. If the ETC processing unit 12 does not permit communication with the vehicle-mounted device, the circuit breaker 1 is closed to prevent the vehicle from passing, for example, to prevent a passing vehicle having an incorrect vehicle-mounted device ID from passing through. Can be.

[0005]

As described above, the ETC
In order to automatically collect the toll from the vehicle by passing the vehicle in the tollgate non-stop through the communication between the vehicle-mounted device and the roadside device, if the antenna unit 4 of the roadside device fails and an abnormality occurs, the vehicle Communication between the antenna and the antenna unit 4 is cut off, and it becomes impossible to collect a toll from the vehicle. For example, if an abnormality occurs in the antenna unit 4 of the roadside device at the entrance tollgate, the entrance tollgate of the ETC vehicle that has passed through the tollgate is unknown, and charging processing cannot be performed. In addition, if an abnormality occurs in the antenna unit 4 of the roadside device at the exit tollgate, the charging process of the ETC vehicle passing through the tollgate cannot be performed, or an erroneous billing is performed. Pass through a vehicle that is not equipped with a container). Such a situation may occur unexpectedly at an unexpected time, and it is not enough to repair the malfunction of the antenna by regular maintenance. It was necessary to identify and repair the generated antenna unit 4 and quickly restore it.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and when an abnormality has occurred in an antenna section, the abnormality is detected, and the system is prevented from going down by autonomously switching to a spare antenna. The purpose is to do.

[0007]

An automatic toll collection system according to a first aspect of the present invention collects tolls by wireless communication between a roadside device installed at a tollgate provided on a road and a vehicle-mounted device mounted on a vehicle. In the automatic toll collection system, a first antenna connected to the roadside device and communicating with the vehicle-mounted device, a second antenna for communicating with the vehicle-mounted device, and abnormality detection for detecting abnormality of the first antenna And a switch for switching the connection with the roadside device from the first antenna to the second antenna when an abnormality is detected by the abnormality detection unit.

An automatic toll collection system according to a second aspect of the present invention is an automatic toll collection system for collecting tolls by wireless communication between a roadside device installed at a tollgate provided on a road and an on-vehicle device mounted on a vehicle. A first antenna that is connected to the roadside device and communicates with the vehicle-mounted device, a second antenna that communicates with the vehicle-mounted device, and an abnormality detection that issues a signal when an abnormality of the first antenna is detected. Unit, when a signal is output from the abnormality detection unit, switching the connection with the roadside device from the first antenna to the second antenna, when the signal from the abnormality detection unit is not output And a switch for switching connection with the roadside device from the second antenna to the first antenna.

An automatic toll collection system according to a third aspect of the present invention is an automatic toll collection system for performing toll collection by wireless communication between a roadside device installed at a tollgate provided on a road and an on-vehicle device mounted on a vehicle. A first antenna connected to the roadside device and communicating with the vehicle-mounted device, a second antenna for communicating with the vehicle-mounted device, and a first abnormality detection unit that detects an abnormality of the first antenna. A second abnormality detection unit that detects abnormality of the second antenna,
A switching device that, when an abnormality is detected in at least one of the second abnormality detection units, switches a connection with the roadside device to the other antenna connected to the abnormality detection unit in which the abnormality is detected. It is.

[0010] In the automatic toll collection system according to a fourth aspect of the present invention, the switch is disposed on an antenna installation base on which the antenna is fixed.

In the automatic toll collection system according to a fifth aspect of the present invention, the abnormality detecting section detects an abnormality in a power supply voltage supplied to the antenna.

[0012] In the automatic toll collection system according to a sixth aspect of the present invention, the abnormality detector detects an abnormality in transmission power supplied to the antenna or an abnormality in reception gain.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 shows an automatic toll collection system according to Embodiment 1 of the present invention.
It is a figure which shows the apparatus structure installed in the roadside of a tollgate, In the figure, 30 is a roadside control apparatus which communicates with a passing vehicle and controls the apparatus installed in the roadside, 4a, 4b is a wireless communication with a passing vehicle. The first and second antenna units for performing communication are shown, and 1, 2, and 5 have the same configuration as the conventional one shown in FIG.

FIG. 2 shows the configuration and connection of the roadside control device 30 and the first and second antenna units 4a and 4b, wherein 6a and 6b denote the first and second antenna units. Antennas for wireless communication in 4a and 4b, 7a and 7
b is a transmission / reception unit for transmitting and receiving wireless communication signals at the first and second antenna units 4a and 4b, and 8a and 8b monitor an abnormality in the device at the first and second antenna units 4a and 4b. An abnormality detection unit that outputs a signal and notifies the occurrence of the abnormality, a device monitoring unit 9 that monitors an abnormality of the device in the roadside control device 3, and a communication 100 that controls the first and second antenna units 4a and 4b. A control unit 12 processes communication information and position information from the passing vehicle provided from the communication control unit 100 and the roadside device control unit 11 to determine an accounting process and an operation of each device. Signal lines for transmitting operation / non-operation signals from the monitoring unit 9 to the transmission / reception units 7a and 7b, and 14a and 14b are abnormality detection units 8a and
8b, a signal line for notifying the device monitoring unit 9 of the abnormality detection;
5a and 15b are transmission / reception units 7a and 7b and communication control unit 100
Are shown, and the roadside device control section 11 is equivalent to the conventional one.

Next, the operation of the communication control unit 100 will be described with reference to the flowchart of FIG. The device monitoring unit 9 includes a transmission / reception unit 7a
The operation of the transmitting / receiving unit 7b is stopped during the operation of, and the first antenna unit 4a is operated to communicate with the passing vehicle 5. At this time, the communication control unit 100 is connected to the signal line 15a, and signals are exchanged between the ETC processing unit 12 and the transmission / reception unit 7a (step S1). The device monitoring unit 9 monitors a signal from the abnormality detecting unit 8a (step S2). When an abnormality occurs in the first antenna unit 4a and a signal is output from the abnormality detecting unit 8a, the device monitoring unit 9 monitors the signal of the transmitting / receiving unit 7a. The operation is stopped, the operation of the transmission / reception unit 7b is started, and the second antenna unit 4b is operated to perform communication with the passing vehicle 5. At the same time, the device monitoring unit 9 switches the connection of the communication control unit 100 to connect to the signal line 15b, and signals are exchanged between the ETC processing unit 12 and the transmission / reception unit 7b (step S3). In this state, the device monitoring unit 9 monitors a signal from the abnormality detection unit 8b (Step S).
4) In particular, when no signal is detected, the current state is maintained. However, when an abnormality occurs in the second antenna unit 4b and a signal from the abnormality detection unit 8b is detected, the signal from the abnormality detection unit 8a is checked. (Step S5).

As described above, by performing the abnormality monitoring of the first antenna unit 4a (the second antenna unit 4b), it is possible to determine whether the abnormality occurs in the first antenna unit 4a (the second antenna unit 4b). Even if there is, the first antenna unit 4a (the second antenna unit 4b) can be automatically switched to the second antenna unit 4b (the first antenna unit 4a) functioning as another backup, and the vehicle-mounted device Can be communicated continuously. That is, the communication control unit 100 can communicate with the vehicle-mounted device with the antenna unit determined to be normal based on the notified monitoring signal.

Here, the abnormality detection unit 8a (the abnormality detection unit 8
The abnormality monitoring of the first antenna unit 4a (second antenna unit 4b) in b) will be described with reference to FIG. The signal received by the antenna 6 is split by the splitter 50 and input to the receiving unit 51. The received signal input to and amplified by the receiving unit 51 is demodulated by the modulation / demodulation unit 53 and is transmitted to the communication control unit 10.
0 is transmitted. The transmission signal transmitted from communication control section 100 is modulated by modulation / demodulation section 53 and transmitted
, A transmission wave is output, split by the splitter 50, and radiated from the antenna 6 to the outside. The power supply voltage monitoring circuit 55
Either the first or second antenna units 4a, 4b and the power supply for normal operation of the circuit of the transmitting / receiving unit 7 are supplied, or the first or second antenna unit 4a,
It monitors whether there is any abnormality in the power supply unit 54 of 4b. The transmission power monitoring circuit 56 includes a circuit that monitors the transmission power of the transmission / reception unit 7, and monitors transmission power abnormality in the transmission unit that transmits radio waves for communication from the roadside device to the vehicle-mounted device. The reception gain monitoring circuit includes a circuit that monitors whether there is no change in the reception gain in the transmission / reception unit 7, and monitors an abnormality in the reception unit that receives a radio wave from the vehicle-mounted device. By monitoring the first or second antenna unit 4 by these three circuits, power supply monitoring of the antenna unit 4 necessary for the entire operation,
Transmission / reception unit 7 required for bidirectional communication with the on-board unit
Can be monitored.

Embodiment 2 FIG. In the first embodiment, even if an abnormality occurs in an antenna unit for communicating with a passing vehicle,
By providing a spare antenna unit, it can be restored immediately, but the process of switching to the spare antenna unit due to the occurrence of an abnormality in the antenna unit has been performed by transmitting a control signal with the roadside control device. In addition, each antenna unit was separately connected to the roadside control device. However, when the switching process to the spare antenna unit is performed by the roadside control device,
It is necessary to transmit the signal that detected the abnormality of the antenna unit to the roadside control device that is located at a distant place.
It is necessary to take noise countermeasures for the wiring extending over several meters. In addition, since each antenna unit is connected to each roadside control device, wiring materials and wiring work increase thereby, and further, the roadside control device side has to prepare an interface with a spare antenna unit. There was a problem.

FIG. 5 is a view showing an antenna unit and a roadside control device of an automatic toll collection system according to a second embodiment of the present invention, which has been made to solve this problem. In the figure, 6a to 12 are equivalent to those in the first embodiment, and 16 is the transmitting / receiving units 7a and 7b and the communication control unit 101.
Is a signal for notifying the abnormal signal from the abnormality detecting unit 8a monitoring the abnormality of the first antenna unit 4a to the transmitting / receiving units 7a and 7b, the switching unit 16 and the device monitoring unit 9. Lines 18a and 18b are transmitting / receiving units 7a and 7
b is a signal line connecting switch 16 and switch 19 is switch 1
6 shows a signal line connecting the communication control unit 6 and the communication control unit 101.

Next, the operation will be described. First, when the first antenna 4a is normal, no abnormality signal is output from the abnormality detection unit 8a, and the transmission / reception unit 7a is operating and the transmission / reception unit 7b
Is stopped, and communication with the passing vehicle 5 is performed by the first antenna unit 4a. In the switch 16, the signal line 18a is used.
And the signal line 19 are connected, and the communication control section 10 exchanges signals with the transmission / reception section 7a.

When an abnormality occurs in the first antenna unit 4a, a signal is output from the abnormality detection unit 8a, the transmission / reception unit 7a stops operating, the transmission / reception unit 7b starts operation, and the passing vehicle 5
Is communicated with the second antenna unit 4b. The switching unit 16 switches the connection between the signal line 18b and the signal line 19, and the communication control unit 101 exchanges signals with the transmission / reception unit 7b.

The signal from the abnormality detecting section 8a is also transmitted to the equipment monitoring section 9, so that the roadside control device 3 can recognize that an abnormality has occurred in the first antenna section 4a.

This embodiment is configured as described above.
Even if an abnormality occurs in the normally used first antenna unit 4a (working system), the operation and connection of the antenna unit are independent of the roadside control device 3 and only when the first antenna unit 4a is abnormal. When the abnormality detection unit 8a is mounted only on the first antenna unit 4a side so as to switch to the normal second antenna unit 4b (standby system) to be used, and when the first antenna unit 4a side becomes abnormal, The system can be operated using the second antenna unit 4b only during the replacement work. At this time, even if an abnormality is detected on the second antenna unit 4b side, there is no antenna that can be switched, so that abnormality detection on the second antenna unit 4b side is not necessary. Providing an antenna switching mechanism for detecting an antenna abnormality on the antenna side (on the road) has the following advantage. Primarily,
This eliminates the need for an antenna switching process due to an interruption in the communication control unit, and shortens the antenna switching time. Second, the antenna is installed on the road and the communication control unit is installed on the roadside, eliminating the need to route the wiring for transmitting the abnormality detection signal over several meters, making it possible to perform false detection due to noise. Is reduced. In addition, it is possible to reduce cost increase due to wiring materials and wiring work, and to reduce malfunction due to wiring mistakes.

Embodiment 3 FIG. FIG. 6 is a diagram showing an antenna unit and a roadside control device of an automatic toll collection system according to a third embodiment of the present invention. In the figure, 6a to 12 are the same as those of the second embodiment, and 20a is a transmitting / receiving unit 7a. A switch that switches between the communication control unit 101 and the communication control unit 101 when a signal is not output from the abnormality detection unit 8a, and switches to a non-connection when a signal is output from the abnormality detection unit 8a. A switch that switches between the units 101 when the signal from the abnormality detection unit 8a is not output, and switches to a connection when the signal from the abnormality detection unit 8a is output. Reference numeral 21 denotes a first antenna unit 4a. A signal line for notifying the transmission / reception units 7a and 7b, the switches 20a and 20b, and the device monitoring unit 9 of an abnormality signal from the abnormality detection unit 8a monitoring the abnormality, and a connection 22 connects the switches 20a and 20b and the communication control unit 10. Faith Shows the line.

First, when the first antenna section 4a is normal, no abnormality signal is output from the abnormality detection section 8a, the transmission / reception section 7a is operating, the transmission / reception section 7b is stopped, and communication with the passing vehicle 5 is not performed. This is performed by the first antenna unit 4a. The switch 20a is in a connected state, and the switch 20a
Since b is in an unconnected state, the communication control unit 101 is connected only to the transmission / reception unit 7a, and signals are transmitted and received during this period.

When an abnormality occurs in the first antenna unit 4a, a signal is output from the abnormality detection unit 8a, the transmission / reception unit 7a stops operating, the transmission / reception unit 7b starts operation, and the passing vehicle 5
Is communicated with the second antenna unit 4b. Further, the switch 20a changes to the unconnected state and the switch 20b changes to the connected state.
b, and signals are exchanged between them.

The signal from the abnormality detecting section 8a is also transmitted to the equipment monitoring section 9, so that the roadside control device 3 can recognize that an abnormality has occurred in the first antenna section 4a.

As described above, even if an abnormality occurs in the first antenna unit 4a, the normal second antenna unit 4a is independent of the roadside control device 3 in both operation and connection of the antenna unit.
Since the switching to b is performed, the wiring work in the roadside control device can be simplified, the cost of wiring material and wiring work can be reduced, and malfunction due to wiring mistakes can be reduced. Also, by providing a simple switch function to turn on / off the interface line with the communication control unit inside the antenna,
When an abnormality is detected on the first antenna 4a side, the second antenna 4
Switching to the b side can be easily performed.

Embodiment 4 FIG. 7 is a diagram showing an antenna unit and a roadside control device of an automatic toll collection system according to a fourth embodiment of the present invention. In the figure, reference numerals 6a to 12 denote the same as those of the second embodiment. , 19
Is the same as in the first embodiment. 23 is a switching control unit that determines the normal one of the first antenna unit and the second antenna unit, controls the operation of the transmitting and receiving units 7a and 7b, and controls the connection to the communication control unit 101; 24b is a signal line connecting the abnormality detection units 8a and 8b and the switching control unit 23,
25a and 25b are transmission / reception units 7a and 7b and switching control unit 2
Reference numeral 26 denotes a signal line connecting the switching control unit 23 to the device monitoring unit 9.

Next, the switching process in the switching control unit 23 will be described with reference to FIG. 4 again. First, the switching control unit 23 operates the transmitting and receiving unit 7a while the transmitting and receiving unit 7a is operating.
b is stopped, and communication with the passing vehicle 5 is performed by the first antenna unit 4a. The switch 16 connects the signal line 18a and the signal line 19, and the communication control unit 101 exchanges signals with the transmission / reception unit 7a (step S1).

The switching control unit 23 monitors a signal from the abnormality detecting unit 8a (step S2). When the signal is detected, the transmitting / receiving unit 7a stops operating, the transmitting / receiving unit 7b starts operating, and the passing vehicle 5 stops. Communication with the second antenna unit 4
b. The switch 16 switches the signal line 18b to connect to the signal line 19, and the communication control unit 101 exchanges signals with the transmission / reception unit 7b (step S).
3).

When the switching control unit 23 is in the state of step S3, it monitors the signal from the abnormality detecting unit 8b (step S4). If no signal is detected, the current state is maintained. Confirms the signal from the abnormality detection unit 8a (step S5).

Here, if the repair of the first antenna unit 4a is completed, the signal from the abnormality detecting unit 8a is not detected, so that the operation of the transmitting / receiving unit 7a is started again, the operation of the transmitting / receiving unit 7b is stopped, and Communication with the vehicle 5 is performed by the first antenna unit 4a. The switch 16 includes a signal line 18a and a signal line 19.
And the communication control unit 10 exchanges signals with the transmission / reception unit 7a (step S1). Also, the first antenna section 4a
If the signal is also detected from the abnormality detection unit 8a because the repair of the device has not been completed, it is determined that a double failure has occurred and the current status is maintained.

In the switching control unit 23, the signals from the abnormality detecting units 8a and 8b are transmitted to the device monitoring unit 9 at the same time as the above operation, so that an abnormality has occurred in the first and second antenna units 4a and 4b. This can also be recognized by the roadside control device 3.

As described above, even if an abnormality occurs in the first antenna unit, the operation is switched to the normal second antenna unit independently of the roadside control device 3 in both the operation and the connection of the antenna unit. If only the replacement work of the first antenna unit is performed, even if an abnormality occurs in the second antenna unit next, it is possible to switch to the first antenna unit that has been similarly replaced,
The interface in the roadside control device can be simplified, and wiring materials and wiring work can be reduced. That is, both the first antenna unit 4a and the second antenna unit 4b are provided with an abnormality detection unit, monitor signals of both abnormality detection units, and perform switching control for constantly connecting a normal antenna to the communication control unit. By having the unit on the antenna side (on the road), the system side recognizes that communication with the on-vehicle device becomes impossible when an abnormality occurs in both the first and second antennas 4a and 4b. Becomes possible. In the second and third embodiments, once the operation is switched to the operation on the second antenna 4b side, even if the operation on the first antenna 4a side is restored, the operation on the first antenna 4a side is resumed. If you forget to put it back,
Even if the second antenna 4b becomes abnormal, the switching operation does not occur and the communication with the vehicle-mounted device becomes impossible, which causes a problem. Since the state can be monitored, occurrence of the problem can be prevented.

[0036]

According to the first to third, fifth, and sixth aspects of the present invention, by monitoring the abnormality of the first antenna that communicates with the vehicle, the abnormality in the first antenna can be reduced. Even if there is, it is possible to switch to another antenna, and it is possible to continuously communicate with the vehicle-mounted device.

Further, according to the fourth aspect of the present invention, it is possible to simplify the interface in the roadside control device, and reduce wiring materials and wiring work.

[Brief description of the drawings]

FIG. 1 is a diagram showing an installation state of roadside equipment at a tollgate in an ETC according to the present invention.

FIG. 2 is a diagram illustrating Embodiment 1 of an antenna unit and a roadside control device according to the present invention;

FIG. 3 is a diagram showing Embodiment 1 of the abnormality detection unit according to the present invention;

FIG. 4 is a diagram showing an operation of the antenna unit and the roadside control device according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating Embodiment 2 of an antenna unit and a roadside control device according to the present invention;

FIG. 6 is a diagram showing Embodiment 3 of an antenna unit and a roadside control device according to the present invention.

FIG. 7 is a diagram illustrating Embodiment 4 of an antenna unit and a roadside control device according to the present invention;

FIG. 8 is a diagram showing a conventional antenna unit and a roadside control device.

FIG. 9 shows a state of installation of roadside equipment at a tollgate in a conventional ETC.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Transmission controller 2 Vehicle detector 3 Roadside control device 4a 1st antenna part 4b 2nd antenna part 5 Passing vehicle corresponding to ETC 6a 1st antenna 6b 2nd antenna 7a 1st transmission / reception unit 7b 2nd Transmission / reception unit 8a First abnormality detection unit 8b Second abnormality detection unit 9 Device monitoring unit 10 Communication control unit 11 Roadside device control unit 12 ETC processing unit 13a Signal line connecting device monitoring unit 9 and transmission / reception unit 7a 13b Device monitoring Signal line 14a connecting the unit 9 and the transmission / reception unit 7b Signal line 14b connecting the abnormality detection unit 8a and the device monitoring unit 9 Signal line 15a connecting the abnormality detection unit 8b and the device monitoring unit 9 15a Transmission / reception unit 7a and communication control unit 10 15b a signal line connecting the transmitting / receiving unit 7b and the communication control unit 10 16 a switch 17 anomaly detecting unit 8a and transmitting / receiving units 7a and 7b, a switching unit 16, Signal line 18a connecting the transmitter / receiver 7 to the switch 16 signal line 18b connecting the transmitter / receiver 7a to the switch 16 signal line 19 connecting the switch 16 to the communication controller 20a Switch 20b Switch 21 Signal line connecting abnormality detection unit 8a with transmission / reception units 7a, 7b, switches 20a, 20b, device monitoring unit 22 Signal line connecting switch 20a, 20b with communication control unit 23 Switching control unit 24a Error detection Signal line 24b connecting the unit 8a and the switching control unit 23b Signal line connecting the abnormality detection unit 8b and the switching control unit 25a Signal line 25b connecting the transmission / reception unit 7a and the switching control unit 23b Transmission / reception unit 7b and the switching control unit 23 26 A signal line connecting the control unit 23 and the device monitoring unit 9

Claims (6)

[Claims] 1. An automatic toll collection system for collecting tolls by wireless communication between a roadside device installed at a tollgate provided on a road and an on-vehicle device mounted on a vehicle. A first antenna for performing communication, a second antenna for performing communication with the on-vehicle device, an abnormality detection unit for detecting an abnormality of the first antenna, and when an abnormality is detected by the abnormality detection unit, An automatic toll collection system, comprising: a switch for switching connection with the roadside device from the first antenna to the second antenna. 2. An automatic toll collection system for collecting tolls by wireless communication between a roadside device installed at a tollgate provided on a road and an on-vehicle device mounted on a vehicle. A first antenna for performing communication, a second antenna for performing communication with the vehicle-mounted device, an abnormality detection unit that emits a signal when an abnormality of the first antenna is detected, and a signal from the abnormality detection unit. When output, the connection with the roadside device is switched from the first antenna to the second antenna, and when the signal from the abnormality detection unit is not output, the connection with the roadside device is changed to the second antenna. An automatic toll collection system, comprising: a switch for switching from the second antenna to the first antenna. 3. An automatic toll collection system for collecting tolls by wireless communication between a roadside device installed at a tollgate provided on a road and an on-vehicle device mounted on a vehicle. A first antenna for performing communication, a second antenna for performing communication with the vehicle-mounted device, a first abnormality detecting unit for detecting an abnormality of the first antenna, and detecting an abnormality of the second antenna A second abnormality detection unit, and when an abnormality is detected in at least one of the first and second abnormality detection units, a connection with the roadside device is connected to the abnormality detection unit in which the abnormality is detected. And a switch for switching to the other antenna. 4. The automatic toll collection system according to claim 1, wherein the switch is arranged on an antenna installation base on which the antenna is installed and fixed. 5. The automatic toll collection system according to claim 1, wherein the abnormality detection unit detects an abnormality in a power supply voltage supplied to the antenna. 6. The automatic toll collection system according to claim 1, wherein the abnormality detection unit detects an abnormality in transmission power supplied to the antenna or an abnormality in reception gain.