JP2000339587A - Bi-directional communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bi-directional communication system efficiently continuing data transfer until the exchange of communication data is ended even when plural road equipment are set at intervals of several km on a general road. SOLUTION: This system is provided with on-vehicle communication equipment 5 and 6 loaded on a traveling object 4, road communication equipment 2 and 3 set on a road for communicating with the on-vehicle communication equipment 5 and 6 by radio, and a central data processor 9 set within a fixed distance from the road communication equipment 2 and 3 for communicating with a road communication equipment group constituted of at least one road communication equipment. Thus, a large volume of data can be transferred through bi-directional communication between road and vehicle on a general road.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-way communication system between a road and a mobile object, and more particularly to a road communication device installed on a road, a vehicle-mounted communication device mounted on a mobile object such as an automobile, and the road communication device. The present invention relates to a system for performing bidirectional communication between the on-road communication device and the on-vehicle communication device in a system including a central data processing device connected to the device via a communication line.

[0002]

2. Description of the Related Art In recent years, a variety of integrated vehicle management systems have been developed with the aim of enhancing road traffic management and operation management of buses and the like. Digital communication is performed between a vehicle and the ground to improve efficiency and reliability. Various road-vehicle communication systems with high efficiency and economy have been proposed.

An example of such a two-way communication system between a mobile unit and a road machine is described in Japanese Patent Application Laid-Open No. 61-112442. In this conventional two-way communication system, when communication is not completed while the mobile object passes through the communicable area of the first roadside device, the remaining communication is performed by the adjacent second communication device.
The data is taken over by the on-road devices, and is successively taken over by a group of adjacent on-road devices until the communication is completed.

[0004]

In the conventional two-way communication system as described above, when road units are installed at intervals of several km on a general road, most road units are connected to other road units. Being adjacent, the central data processing unit needs to communicate with a very large number of road machines,
There is a problem that communication efficiency is significantly reduced.

The present invention has been made in order to solve the above-mentioned problems. Even in the case where road machines are installed at intervals of several kilometers on a general road, efficient exchange of communication data is completed until the exchange of communication data is completed. It is an object of the present invention to obtain a continuous two-way communication system.

[0006]

According to a first aspect of the present invention, there is provided a two-way communication system mounted on a mobile object, and a road communication device installed on a road and communicating with the on-vehicle communication device wirelessly. And a central data processing device for communicating with the group of at least one on-road communication device under predetermined conditions from the on-road communication device.

In a two-way communication system according to a second aspect of the present invention, the central data processing device communicates with a group of at least one road communication device within a certain distance from the road communication device.

[0008] In a two-way communication system according to a third aspect of the present invention, the on-road communication device has a communication data holding area corresponding to the number of mobile units smaller than the actual traffic amount.

In a two-way communication system according to a fourth aspect of the present invention, the central data processing device communicates with a group of at least one on-road communication device having a distance equal to or less than a predetermined length from the on-road communication device. .

According to a fifth aspect of the present invention, in the two-way communication system, the central data processing device comprises at least one on-road device having a value obtained by dividing a distance from the on-road communication device by a road speed limit is equal to or less than a predetermined value. It communicates with the communication device group.

[0011] In the bidirectional communication system according to a sixth aspect of the present invention, the central data processing device communicates with a group of at least one high-frequency communication device on the road based on the communication history. .

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 A two-way communication system according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a configuration of a two-way communication system according to Embodiment 1 of the present invention. In the drawings, the same reference numerals indicate the same or corresponding parts.

In FIG. 1, an on-road communication device comprising an on-road device 2 and an on-road transceiver 3 is provided on the road 1 near the communication area. On the other hand, the vehicle 4 also has
And an on-vehicle communication device including an on-vehicle transceiver 6. The vehicle 4 provided with the on-vehicle device 5 and the on-vehicle transceiver 6 is connected to a communicable area 7 provided on the traveling road 1.
, Data is exchanged between the road device 2 and the on-vehicle device 5 via the road transceiver 3 and the on-vehicle transmitter 6.
The data includes a unique number of the vehicle 4, the position information of the vehicle, the contents of the information request, and the like. These are received and demodulated by the roadside device 2 and transmitted to the central data processing device 9 via the communication circuit 8. .

Next, the configuration of the peripheral road machine group will be described with reference to FIG. 2 and FIG.

In FIG. 2, reference numeral 11 denotes a route network through which a moving body such as a vehicle travels. A roadside device is installed on the route 11 to perform road-vehicle communication. It is assumed that the communicable area 7 of the roadside device 2 is sufficiently narrower than the interval between the routes.

Now, the vehicle 4 is within the communicable area of the road unit 10 (hereinafter referred to as the first road unit) and the vehicle unit 5 of the vehicle 4
Is communicating with the first roadside machine 10, and after communicating with the first roadside machine 10, it communicates with the vehicle 4 among the roadside machines that can communicate with the next roadside machine on the route on which the vehicle 4 can move. When the road machines 10 and 101 to 108 are arranged at the positions shown in FIG.
4, 105, 107, and 10 constitute a group of roadside aircraft around the first roadside aircraft. In the first embodiment, the determination of the peripheral on-road aircraft group is performed under conditions within a certain distance from the first on-road aircraft.

Next, after communicating with the first road unit 10, it is assumed that the communication with the road unit 102 in the peripheral road unit group has been completed. If the data exchange has not been completed even after the update here, this road unit A group of road devices adjacent to the device 102 (hereinafter referred to as a second road device) is obtained.

When the road units are arranged as shown in FIG. 3, the road units 10, 101, 103, 110 and 102 are determined as a group of road units around the second road unit 102. The third,
The peripheral road machine group is determined until the data exchange with the fourth road machine is completed.

That is, the central data processing device 9 searches for a road device within a certain distance from a certain road device among the road devices registered in the database in advance, and registers it in the database as a group of peripheral road devices in advance.

Next, the operation of the two-way communication system according to the first embodiment will be described with reference to the drawings. 4 to 6 are flowcharts illustrating the operation (road-vehicle communication procedure) of the two-way communication system according to Embodiment 1 of the present invention.

FIG. 4 is an extract flow in the central data processing device 9. First, in step 401, data is received from the roadside device 2 via the communication line 8. This data is
It is composed of a roadside machine number, a vehicle number, request information from the vehicle-mounted device 5, arbitrary data from the vehicle-mounted device 5, a data exchange end state, and the like. With the reception of the data, response data is created from a database or the like of the central data processing device 9.

Next, in step 402, it is determined whether or not the previous data transmitted to the group of on-road peripheral devices addressed to the vehicle of the source of the received data has been successfully transmitted to the vehicle-mounted device 5 of the destination vehicle from the state of completion of the exchange of the received data. If the transmission has not been completed, the previous data is transmitted to the group of peripheral road devices corresponding to the road device that received the current data in step 405.

Next, in step 403, it is checked whether or not the data not transmitted to the vehicle which has transmitted the received data is stored in the central data processing device. The data is transmitted to the group of peripheral road devices corresponding to the received road device, and this flow is repeated again.

As described above, it is assumed that the peripheral road machine group corresponding to each road machine has already been constructed in the database of the central data processing device 9. When transmitting data to the peripheral road machine group in step 404, it is assumed that the vehicle-mounted device 5 adds information for preventing double processing of the same data to the data and transmits the data. In step 405, the same as in the previous transmission It is assumed that information is added and transmitted. It is also assumed that the data transmitted in steps 404 and 405 are divided in advance into a size equal to or less than the maximum amount of information transmission that can be performed by the roadside device 2 to communicate with the vehicle-mounted device 5.

FIG. 5 is an extract flow of the vehicle-mounted device 5. First, in step 501, polling data transmitted from the roadside device 2 via the roadside transceiver 3 is taken into the vehicle-mounted device 5 via the vehicle-mounted transceiver 6. This polling data
It consists of a roadside machine number and a polling identifier.

Next, in step 502, the on-vehicle device 5 transmits its own vehicle number, a request for required information, and arbitrary data to the on-road device 2. If there is no request for required information to be transmitted and no data, only the vehicle number shall be transmitted.

In step 503, the data requested in the previous step 502 is received, and the remaining data of the data transfer that has not been completed in the previous communication is received.

Next, in step 504, it is checked from the information added to the data whether the received data has already been received.
If the data has not been received, a process corresponding to the received data is performed in the next step 505.

FIG. 6 is an extract flow of the on-road unit 2. First, in step 601, data (corresponding to steps 404 and 405 in FIG. 4) is received from the central data processing device 9, and in the next step 602 it is checked whether data has been received. The received data is stored in the communication data holding area of the roadside device 2. The communication data holding areas are prepared for the number of on-vehicle devices 5 based on, for example, the actual traffic amount, and can store one data each. When new data is received, it is overwritten.

Next, in step 604, polling data is issued to the vehicle-mounted device. This polling data is composed of a roadside machine number and a polling identifier as described above.

Then, in step 605, response data (corresponding to step 502 in FIG. 5) from the vehicle-mounted device 5 is received.

Next, it is checked in step 606 whether response data has been received from the vehicle-mounted device 5.

If the response data has been received, step 6
In step 07, it is checked whether or not the data for the vehicle communicating with the communication data holding area in the on-road device is held. If the data is held, the held data is transmitted to the in-vehicle device 5 in the next step 608. Deletes the data held in the communication data holding area.

Thereafter, in step 610, the response data is transmitted to the central data processing device 9.

As described above, according to the first embodiment, even when road devices are installed at intervals of several km on a general road, a plurality of on-vehicle devices 5 provided on the moving vehicle 4 are provided. Since a series of data exchange with the road machine 2 can be efficiently performed, an arbitrary amount of information can be transmitted to the central data processing device 9 via a plurality of road machines.

That is, the two-way communication system according to the first embodiment includes the on-road communication devices 2, 3 installed on the road.
The mobile unit communicates with the roadside communication device by a communication system including a vehicle-mounted communication device 5 and 6 mounted on the mobile unit 4 and a central data processing device 9 connected to the roadside communication device via a communication line 8. In the two-way communication system between the road and the mobile unit, which communicates with the road communication device while passing through the available area 7, the communication is completed while the mobile unit passes through the communicable area of the first road communication device. If not, the remaining communication is performed within a communicable area of one second roadside communication device of a group of at least one roadside communication device within a certain distance from the first roadside communication device, and If the communication is not completed after passing through the respective communicable areas of the first road communication device and the second road communication device, the communication is sequentially performed until communication is completed with one of the peripheral road communication devices. Take over It is characterized in.

As described above, according to the first embodiment, even when the on-road units 2 are installed at intervals of several kilometers on a general road, the on-board units 5 provided on the moving body are installed on the road. Data exchange with the roadside device 2 that has passed through the communicable range of the roadside device so as to be efficiently carried over to another roadside device in the vicinity, so that both road-to-vehicle traffic on a general road can be performed. Bidirectional communication can perform large-capacity data transfer.

Embodiment 2 In the first embodiment,
The communication data holding areas are prepared in the roadside unit 2 for the number of on-board units. In the second embodiment, the communication data holding regions are prepared in a number equal to or less than the number of on-board units, and new data is stored with priority.

The second embodiment is different from the above embodiment in that the communication time and the vehicle number are added to the communication data holding area, and the number is smaller than the number of onboard units according to the actual traffic volume. Same as 1.

Further, in the second embodiment, the detailed operation when the roadside device 2 stores the data received from the central data processing device 9 in the communication data holding area in the step 603 of FIG. 6 in the first embodiment. However, except that the flow is as shown in FIG.

Next, the operation for storing received data in the communication data holding area will be described with reference to FIG. First, an unused area is searched for in step 701, and if no unused area is found, then in step 703 an area with the oldest communication time is searched.

Thereafter, the time, destination vehicle number, and communication data are stored in the area found by the search in step 704.

According to the second embodiment, it is possible to efficiently communicate with a large number of vehicle-mounted devices using a small amount of resources.

Embodiment 3 FIG. In the first embodiment,
Although a condition within a certain distance from the first on-road machine was used to determine a peripheral on-road machine group corresponding to the first on-road machine, in the third embodiment, the distance from the first on-road machine is within a certain length. Use conditions.

The configuration and operation in the third embodiment are the same as those in the first embodiment except for the method of obtaining the configuration of the peripheral roadside aircraft group.

Next, the configuration of a group of peripheral road machines according to the third embodiment will be described with reference to FIG. In FIG. 8, reference numeral 811 denotes a route network in which a moving body such as a vehicle travels, and it is assumed that routes intersect, for example, every 1 km vertically and horizontally.

Now, it is assumed that the on-road units 801 to 809 are arranged at the positions shown in FIG. 8, and the on-vehicle units 5 of the vehicle 4 are updated in the communicable area of the on-road units 805 and the on-road units 805. In the third embodiment, for example, when the conditions are set to be within 3 km of the road, the road devices adjacent to the first road device are road devices 802, 804, 805, 806, and 808 within the range indicated by 810. According to the third embodiment, road-vehicle communication can be performed more efficiently than in the first embodiment.

Embodiment 4 In the first embodiment,
The conditions within a certain distance from the first on-road aircraft were used to determine the peripheral on-road aircraft group corresponding to the first on-road aircraft. In the fourth embodiment, the length of the route from the first on-road aircraft and the definition of each route are defined. The time required for the movement is obtained based on the set speed limit, and a condition that the movement time is equal to or less than a predetermined value is used.

The configuration and operation of the fourth embodiment are the same as those of the first embodiment except for the method of obtaining the configuration of the peripheral roadside aircraft group.

Next, the configuration of a group of peripheral on-road units according to the fourth embodiment will be described with reference to FIG. In FIG. 9, reference numeral 930 denotes a route network in which a moving object such as a vehicle travels.

In FIG. 9, one vertical route 931 in the route network 930 has a speed limit of 60 km / km.
Hour, other routes are 30 km / hour.

Now, it is assumed that the road units 901 to 915 are arranged at the positions shown in FIG. 9 and the vehicle-mounted unit 5 of the vehicle 4 is communicating with the road units 908 within the communicable area of the road unit 908. In the fourth embodiment, for example, when the traveling time is set to 5 minutes or less, the roadside machines 902, 905, 907, 908, and 90 in the range (dotted line) indicated by 920 are located around the first roadside aircraft.
9, 911 and 914. According to the fourth embodiment, road-vehicle communication can be performed more efficiently than in the first and second embodiments.

Embodiment 5 In the first embodiment,
Although the conditions within a certain distance from the first on-road aircraft are used for determining the peripheral on-road aircraft group corresponding to the first on-road aircraft, in the fifth embodiment, the initial state is used for determining the peripheral on-road aircraft group in the first embodiment. Then, statistics are taken on which road machine to communicate with after the first road machine, and a peripheral road machine group corresponding to each road machine is dynamically determined based on the statistical value.

The configuration and the operation in the fifth embodiment are such that a communication history table is provided on the central data processing unit 9 for holding a fixed number of the numbers of the road machines which have communicated with each of the road devices after the road device. 4 except that the central data processing device 9 dynamically receives the data from the vehicle 4 in step 401 of FIG. The same shall apply.

Next, a method of dynamically determining a group of peripheral aircraft on the road will be described with reference to FIG. First, in step 1001, the oldest history is deleted from the communication history table of the road machine with which the transmission source vehicle communicated last time.

Next, in step 1002, the number of the on-road unit that has received the data this time is added to the communication history table.

Subsequently, in step 1003, communication is performed a predetermined number of times or more from the communication history table, the number of higher-ranking road units is determined by comparing the numbers, and in step 1004, a group of peripheral road units corresponding to the previously updated road units. And register it in the database. According to the fifth embodiment, the first embodiment
And 2, it is possible to more efficiently perform road-vehicle communication.

[0058]

As described above, the two-way communication system according to the first aspect of the present invention includes a vehicle-mounted communication device mounted on a mobile body and a road-based communication that is installed on the road and wirelessly communicates with the vehicle-mounted communication device. Device and a central data processing device for communicating with at least one on-road communication device group of predetermined conditions from the on-road communication device, so that large-capacity data transfer can be performed by road-to-vehicle bidirectional communication on a general road. This has the effect that it can be performed.

In the two-way communication system according to the second aspect of the present invention, as described above, the central data processing device communicates with at least one road communication device group within a certain distance from the road communication device. Therefore, there is an effect that large-capacity data transfer can be performed by road-to-vehicle bidirectional communication on a general road.

As described above, in the two-way communication system according to the third aspect of the present invention, since the on-road communication device has a communication data holding area for the number of mobile units smaller than the actual traffic volume, a large number of There is an effect that communication can be efficiently performed with a small amount of resources to the vehicle-mounted device.

As described above, in the two-way communication system according to a fourth aspect of the present invention, the central data processing device includes a group of at least one road communication device having a distance of a predetermined length or less from the road communication device. Since communication is performed, there is an effect that large-capacity data transfer can be performed by road-to-vehicle bidirectional communication on a general road.

[0062] In the two-way communication system according to claim 5 of the present invention, as described above, the central data processing device determines that at least a value obtained by dividing the distance from the on-road communication device by the speed limit of the road is equal to or less than a predetermined value. Since communication is performed with a single road communication device group, there is an effect that large-capacity data transfer can be performed by road-to-vehicle bidirectional communication on a general road.

As described above, in the bidirectional communication system according to the sixth aspect of the present invention, the central data processing device is connected to a group of at least one high-frequency communication device on the road based on the communication history. Since communication is performed, there is an effect that large-capacity data transfer can be performed by road-to-vehicle bidirectional communication on a general road.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a bidirectional communication system according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a method of determining a group of peripheral road machines in the two-way communication system according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating a method for determining a group of peripheral road devices in the two-way communication system according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing an operation of the central data processing device of the two-way communication system according to Embodiment 1 of the present invention.

FIG. 5 is a flowchart showing an operation of the vehicle-mounted device of the two-way communication system according to the first embodiment of the present invention.

FIG. 6 is a flowchart showing an operation of a roadside device of the two-way communication system according to the first embodiment of the present invention.

FIG. 7 is a flowchart showing a communication data holding area updating operation of a roadside device of the two-way communication system according to Embodiment 2 of the present invention;

FIG. 8 is a diagram illustrating a method for determining a group of peripheral road devices in a two-way communication system according to Embodiment 3 of the present invention;

FIG. 9 is a diagram showing a method for determining a group of peripheral road devices in the two-way communication system according to Embodiment 4 of the present invention.

FIG. 10 is a flowchart showing an operation of determining a peripheral road machine group of the central data processing device of the two-way communication system according to Embodiment 5 of the present invention;

[Explanation of symbols]

1 road, 2 road machines, 3 road transceivers, 4 vehicles,
5 On-board unit, 6 On-board transceiver, 7 Communication area, 8
Communication circuit, 9 central data processing unit.

Claims (6)

[Claims] 1. An on-vehicle communication device mounted on a mobile object, a on-road communication device installed on a road and communicating with the on-vehicle communication device wirelessly, and a on-road communication device comprising at least one of predetermined conditions from the on-road communication device A two-way communication system comprising: a central data processing device that communicates with a group. 2. The two-way communication system according to claim 1, wherein the central data processing device communicates with a group of at least one road communication device within a certain distance from the road communication device. 3. The two-way communication system according to claim 1, wherein the on-road communication device has a communication data holding area corresponding to the number of mobile units smaller than the actual traffic amount. 4. The apparatus according to claim 1, wherein the central data processing device communicates with a group of at least one on-road communication device having a predetermined length or less from the on-road communication device.
A two-way communication system as described. 5. The central data processing device communicates with a group of at least one road communication device having a value obtained by dividing a distance from the road communication device by a speed limit of a road to a certain value or less. Item 2. The two-way communication system according to Item 1. 6. The two-way communication system according to claim 1, wherein the central data processing device communicates with a group of at least one roadside communication device having the highest frequency of communication based on the communication history.