JP2573732B2 - Mobile communication system and on-board radio in mobile station - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a mobile communication system and an on-board radio in the mobile station, and more particularly to a mobile communication system that performs communication while recognizing the location of the mobile station. Further, the present invention relates to an on-board radio in a mobile station applied to the mobile communication system.

(Prior Art) Conventionally, as a mobile communication system applied to a vehicle such as an automobile, for example, a plurality of fixed stations (road equipment) are arranged at predetermined intervals along a road to provide an intermittent communication area. A mobile communication system called "intermittent minimum zone system" has been proposed in which communication is performed via fixed stations when vehicles pass through these communication areas (Japanese Patent Application No. 63-38407). No.).

In recent years, as a communication system based on such a mobile communication system, the on-road unit receives a radio signal transmitted from the on-board unit of each vehicle when the vehicle passes through those communication areas. By recognizing the position of each vehicle and measuring the traffic flow, the traffic flow grasping system (AVI) and the vehicles recognized by this traffic flow grasping system are instructed from related organizations via roadside machines. Giving,
Automatic vehicle operation management system (AVM) that manages the operation
A mobile communication system combining the above is considered. In this mobile communication system, a specific mobile station code is assigned to each in-vehicle device by an on-board device contract when a mobile station is subscribed, and this mobile station code is used by a traffic flow grasp system and an automatic vehicle operation management system. Use commonly.

The traffic flow grasping system detects the position information of the vehicle by receiving the mobile station code transmitted from the mobile station in the communication area of each on-road unit, and calls the vehicle position information as a road-to-vehicle information center. The traffic flow is recorded in the information system center database. Also,
This system is provided with a service for transmitting road information such as weather, regulations, and traffic jams to each mobile station to provide a route guidance service for vehicles.

The automatic vehicle operation management system detects the corresponding mobile station based on the position information of the mobile station detected by the traffic flow grasping system by each mobile station code, and, for example, the operation manager of the contracted company operates the road-to-vehicle information center. From the company and the detailed road traffic information, and provides the operation management and instructions of the company's aged car to the corresponding mobile station via the roadside machine. In this case, communication with the mobile station is performed bidirectionally by voice message, facsimile or image.

(Problems to be Solved by the Invention) However, in the conventional technology, the traffic flow grasping system receives the mobile station code unique to the subscribed vehicle assigned to each mobile station and can grasp all the subscribed vehicles. If the traffic flow grasping system is connected to another system, in this case, if it is connected not only to an automatic vehicle operation system, but also to a traffic enforcement system, for example, the position information of the vehicles that you do not want to know may be arbitrarily detected. , There was a fear that the privacy of the vehicle owner would be compromised.

In order to prevent this, if the mobile station code is registered in the traffic flow grasp system only when the vehicle communicates with the automatic vehicle management system, the number of vehicles measured by the traffic flow grasp system decreases. Therefore, there is a problem that the accuracy of the traffic flow measurement is reduced.

The present invention solves such disadvantages of the prior art,
Even when the traffic flow grasping system is connected to another system, the privacy of the vehicle owner can be protected without lowering the accuracy of the traffic flow measurement, and the communication efficiency of each system decreases. It is an object of the present invention to provide a mobile communication system that does not have any problem and an on-board radio device in the mobile station.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention forms intermittent communication areas by arranging fixed stations at predetermined intervals along a path of a moving body. A traffic flow grasping system in which each fixed station in a communication area receives a radio signal transmitted from the mobile station to detect position information of each mobile station and measure the traffic flow; Based on the location information of the mobile station detected by the grasping system,
In a mobile communication system applied to the mobile station and a system other than the traffic flow grasping system that performs communication via the fixed station, when the mobile station is turned on when the power of the on-board radio is turned on, When a pseudo code different from the assigned unique code is generated and communication with a system other than the traffic flow grasp system is performed, the unique code assigned to the radio is transmitted from the transmitting unit in the communication area of the fixed station. When transmitting as a radio signal and performing communication only with the traffic flow grasping system, a pseudo code generated at power-on is transmitted as a radio signal from a transmission unit in a communication area of a fixed station.

Further, in the mobile communication system of the present invention, the traffic flow grasping system is configured such that the fixed station receives either a unique code assigned to each mobile station or a pseudo code generated by the mobile station when the power is turned on. It is characterized by detecting position information of each mobile station and grasping their traffic flow.

In addition, other systems besides the traffic flow grasp system,
Based on the detection of the unique code assigned to the mobile station by the traffic flow grasping system, the mobile station communicates with the mobile station via each fixed station.

The on-board radio in the mobile station of the present invention generates a pseudo-code by generating a random number when the power is turned on, and generating a pseudo-code based on the random number, the power-on time, and the unique code assigned to the radio. Generating means, storing means for respectively storing the pseudo code and unique code generated by the pseudo code generating means, a communication mode for communicating with a system other than the traffic flow grasp system, and communication with only the traffic flow grasp system. Switch means having a non-communication mode to perform, and storage means for judging the state of the switch means and, when the mobile station passes through the communication area of the fixed station, when the switch means is in the communication mode. When the switch is in the non-communication mode, it reads the unique code stored in the It reads the pseudo code stored in the storage means, characterized by comprising a control means for transmitting as radio signals the pseudo code from the transmitting unit.

(Operation) According to the mobile communication system of the present invention and the on-board radio in the mobile station, the mobile station communicating with a system other than the traffic flow grasping system selects the switch means of the on-board radio in the communication mode. Thus, in each communication area where the fixed station is located, the unique code assigned to the wireless device is transmitted from the mounted wireless device to the fixed station to notify the traffic flow grasping system of its location. As a result, the traffic flow grasping system can detect the position information of the mobile station and its affiliation, and other systems can communicate with the mobile station based on the detection result of the mobile station by the traffic flow grasping system.

In addition, when the mobile station communicates only with the traffic flow grasping system, by selecting the non-communication mode of the switch means of the on-board radio, the mobile station receives a random number in each communication area where the fixed station is located. The masked pseudo code is transmitted from the on-board radio to the fixed station to notify the traffic flow grasping system of its location. As a result, the traffic flow grasp system
By detecting only the position information of the mobile station, detection of the own station by another system or the like is prevented.

(Embodiment) Next, an embodiment of a mobile communication system according to the present invention and an on-board radio in a mobile station thereof will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment in which the mobile communication system according to the present invention is applied to land traffic, particularly road traffic of vehicles including automobiles, as a road-to-vehicle individual communication system. The road-to-vehicle individual communication system has a traffic flow grasping system for measuring a traffic flow of a vehicle in road traffic, and allows a user of a specific user, for example, to manage the traffic of a specific user grasped by the traffic flow grasping system. And an automatic vehicle operation system.

In this embodiment, in order to configure these systems, a plurality of road stations 10 are arranged at predetermined intervals along a general road or an expressway, for example, at intervals of several hundred meters to several kilometers depending on the vehicle speed allowed on the road. Are located. The road station 10 is a fixed station that functions as a base station that wirelessly communicates with a subscribing vehicle 12 passing on the road.

The road station 10 has a transceiver 14, which
The vehicle transmits and receives radio waves 18 to and from a wireless device (vehicle device) 160 shown in FIG.

The zone 20 has a service area much smaller than the arrangement interval of the road stations 10, and intermittent communication as a whole is performed by a plurality of road stations 10 intermittently arranged at predetermined intervals. A so-called “intermittent minimum zone method” for forming an area is adopted. Zone 20 is referred to as a “minimal zone”.

The diameter of this zone 20 is, for example, several tens of meters to 10
It is on the order of 0 meters, and between the two adjacent zones 20, there is an area where the on-vehicle device 160 does not substantially respond to the radio wave transmitted by the road station 10, that is, a "radio wave area". ing. The vehicle 12 can communicate with the road station 10 only while being included in the zone 20. This communication is performed at high speed.

The same frequency is repeatedly used for the adjacent road station 10. Basically, for a wireless link between the road station 10 and the on-vehicle device 160 of the vehicle 12, it is sufficient to use a single frequency for the entire system. In this case, a pair of frequencies that are different from each other at the top and bottom are used.

The road station 10 constitutes a part of the road-vehicle individual communication network 22, and accesses communication facilities such as a road-vehicle information center 26 (system center) and a user center 28 via the network 22.

The road-vehicle individual communication network 22 is a communication network for performing switching, that is, switching, between the vehicle 12 and the road-vehicle information center 26 and the user center 28.

In the present system using such an intermittent minimum zone system, the speed of communication between the vehicle 12 and the road station 10 can be increased, and various services including high-speed data communication are provided.

For example, in this embodiment, the traffic flow grasping system provides a navigation service for guiding the subscribing vehicle 12 such as an automobile to an appropriate route according to road congestion and weather conditions.

In the automatic vehicle operation system, various information and instructions are transmitted to the vehicle 12 by performing two-way communication in order to efficiently manage the operation of many vehicles 12.

For the purpose of providing these services, road-to-vehicle individual communication network
Communication is performed between the centers 26 and 28 and the vehicle 12 (mobile station 16) via 22.

FIG. 2 is a diagram showing a relay system of the road-to-vehicle individual communication line network. 30, a regional station 32 accommodating a plurality of district offices 30 over a certain area, and a general bureau 34 accommodating some of these regional offices 32.

In this embodiment, the lines between the regional stations 30, the regional stations 32 and the general office 34 are trunk lines 36 such as trunk lines and oblique lines.
And a general network is formed between the general control stations 34. In the present invention, the present invention is not limited to this network form. For example, it is possible to adopt a station hierarchy configuration corresponding to a road form such as a general road or an expressway, or another form such as a linear network. Needless to say. As shown in FIG. 1, the general office 34, the regional office 32 or the regional office 30 may house a trunk line 38 for the general telephone line network 24 and the data exchange network 25 provided to the general public.

The road-to-vehicle information center 26 has a database for accumulating the position information of the mobile station 16 (vehicle) captured by the road station 10, as well as road conditions such as weather or road regulation and traffic congestion in each region. An information processing system center that includes a database having information and processes navigation of the subscribed vehicle 12.

The user center 28 is an information processing system center that independently manages the operation of those belonging to a specific user or the like among the subscribed vehicles 12. This user center 28
It obtains various kinds of information together with the position information of the vehicle 12 from the database of the road-to-vehicle information center 26 and gives an instruction for operation to its own vehicle or the like.

Both are housed in a general bureau 34 by a trunk line 40.
Of course, these may be connected to the regional office 32 or the regional office 30.

The general bureau 34, the regional bureau 32 and the district bureau 30 each have a unique bureau code. By representing the codes of the supervising station 34 and the regional station 32 in the station hierarchy, a registered ground station code 52 (see FIG. 3) for specifying the regional station 32 is determined.

Subscription vehicles for large users with a large number of subscription vehicles 12
For 12, a user code unique to the user may be used instead of the regional office code.

The mobile station 16 mounted on the joining vehicle 12 is registered in the local station 32 in this embodiment, and the local station 32 assigns a mobile station code 540 (see FIG. 3) to each of the mobile stations 16. . Therefore, nationwide, the mobile station 16, that is, the on-board unit 160, has the registered ground station code 52 and the mobile station code 5.
Specified at 40. The joining vehicle 12 may be registered in the general bureau 34 or the district bureau 30.

FIG. 3 shows an example of the format of the vehicle-specific code assigned to each subscribing vehicle mobile station 16, including the registered ground station code 52 and the mobile station code 540 assigned as described above. In this embodiment, the assigned mobile station-specific code is used when receiving the service of the vehicle operating system. When only the traffic flow grasp system is used, a pseudo code 542 having the same digit as the mobile station code 540 is used as described later.

Regardless of whether the mobile station code 540 or the pseudo code 542 is used, the code specifying the vehicle 12 is composed of the static code 50 and the dynamic code 60 in the present embodiment. You.

The static code 50 is a code for identifying the mobile station 16 captured by the road station 10, and includes a ground station code 52 and a mobile station code.
540 or a vehicle specific code 54 consisting of a pseudo code 542,
And a system code 56 for identifying the present system. The system code 56 is a code for designating the present system distinguished from other systems, and may be omitted inside the present system.

The static code 50 has a function as an identification number of each mobile station 16 in the present system, and has a close relationship with a number system when receiving a call from the centers 26 and 28 to the mobile station 16. In particular, when the user center 28 recognizes the vehicle, the mobile station code 540 assigned to each mobile station 16 is used as the vehicle unique code 54. In the road-to-vehicle information center 26, any one of the mobile station code 540 and the pseudo code 542 may be used as the vehicle-specific code 54.

When the mobile station code 540 is used as the vehicle-specific code 54, the static code 50 specifies the affiliation of the vehicle 12 and the like, and receives the vehicle-specific information, that is, receives the service of the automatic vehicle operation system. It is advantageous in the case.

The use of the pseudo code 542 as the vehicle-specific code 54 is advantageous in a case where the vehicle is not specified and only the service common to all the vehicles, that is, the service of the traffic flow grasp system is received.

The dynamic code 60 is a code corresponding to the moving state of the joining vehicle 12, and is effectively used for grasping the current situation of the joining vehicle 12 and navigating. Therefore, the joining vehicle 12
This is a vehicle-specific code related to the travel area and travel status of the vehicle, and is used to search for vehicle locations for individual communication from the centers 26 and 28, and to provide route guidance information for the participating vehicles 12 to travel destinations, etc. Play an important role. Therefore, in the present embodiment, a destination code 62 indicating the operation destination of the joining vehicle 12 and a travel destination area code 64 indicating the current travel destination area are included. The running district code 64 corresponds to the general bureau 34, the regional bureau 32 and the district bureau 30.
Station code. In addition, a link code for specifying the set communication link may be included.

In the present embodiment, as shown in FIG.
80 are provided in the regional office 32. In the traveling vehicle table 80, data indicating the current traveling area of each of the participating vehicles 12 of the own station registered as belonging to the local station 32 is stored for each station area. Data on the subscribed vehicles 12 traveling in the area is stored for each registration authority. These data in the traveling vehicle table 80 are constantly updated and transferred to the road-to-vehicle information center 26. A similar vehicle table may be provided in, for example, the district office 30 or the general bureau 34 as illustrated by a dotted line 84 in the case of the district office 30 in FIG.

As conceptually shown in FIG. 1, a memory 42 is provided in the road station 10 and includes a passing vehicle table 82 (FIG. 2),
It includes a storage area in which information to be transmitted to and received from the mobile station 16 is stored. The passing vehicle table 82 holds data on the joining vehicles 12 passing through the minimum zone 20 of the road station 10.
These data include codes 50 and 60,
It is constantly updated with the passage of 12, and is transferred to the database of the road-to-vehicle information center 26.

In this embodiment, the mobile station 16 is mounted on a subscribing vehicle 12 such as an automobile, transmits and receives data such as navigation information and operation management information, messages and image signals to and from the road station 10, and transmits these signals to the passenger. Visible and / or
It is an in-vehicle device that performs audible display. Preferably, a video display, a facsimile transmitting / receiving device, a voice synthesizing device, and the like for interfacing with a boarding vehicle with images and voices are provided. Further, an automatic operation control function for the control mechanism of the joining vehicle 12 may be provided. The mobile station 16 has a random number table function, and according to the bowling from the road station 10, among the plurality of channels in the link 18 with the road station 10, an available free channel is selected by the road station 10. You.

The in-vehicle device 160 of the mobile station 16 will be described in more detail with reference to FIG. 4 and FIG. FIG. 4 is a block diagram showing the configuration of the vehicle-mounted device, and FIG. 5 is a diagram showing a pseudo code generation process.

As shown in FIG. 4, the in-vehicle device 160 includes a wireless transmission / reception unit 162, a storage unit 164, a mode changeover switch 166,
A pseudo code generation unit 168, a clock unit 170, and a control unit 172 are provided.

The wireless transmission / reception unit 162 communicates with the road station 10 in a time-division transmission system (TDM
A wireless transmission / reception unit that transmits / receives a radio signal according to A), and transmits / receives data including the vehicle-specific code 54 shown in FIG.

The storage unit 164 includes an area B for constantly storing the mobile station code 540 allocated at the time of the subscription contract, and a pseudo code generation unit 168.
The area C for storing the pseudo code 542 generated at the time until the power is turned off, and either the area B or the code stored in the area C are read and transferred under the control of the control unit 172, and the wireless transmission / reception unit 162 is read. And an area A for storing the vehicle-specific code 54 transmitted by

The mode changeover switch 166 is a switch that selects a communication mode when receiving the service of the automatic vehicle operation system and a non-communication mode when not receiving the automatic vehicle operation system.

The pseudo code generation unit 168 is a circuit that generates a random number when the power is turned on, and generates a pseudo code 542 based on the time and the mobile station code 54. For example, as shown in FIG.
Is 10 digits, this mobile station code 540 has time (4 digits) 500
And a process of adding a random number 72 generated when the power is turned on to the 14-digit code 70. The pseudo code generation unit 168 extracts an arbitrary six-digit number from the processing result to form a processing code 74. Further, the pseudo code generation unit 168 adds a four-digit code, such as "9999", which is not used for the mobile station code 540, to the head of the six-digit processing code 74, and adds In this configuration, a pseudo-code 542 of the same digit as the station code 540 is generated.

Referring again to FIG. 4, the clock unit 170 incorporates a backup battery and keeps time even when the power is off.

The control unit 172 is a circuit that controls each unit.In particular, when the power is turned on, the time of the clock unit 170 is read and sent to the pseudo code generation unit 168, and the pseudo code 542 generated by the pseudo code generation unit 168 is transmitted. The control for generating the pseudo code to be written into the area C of the storage unit 164 and the state of the mode changeover switch 166 are read, the state is determined, and the mobile station code 540 stored in the area B is stored in the area A of the storage unit 164. Alternatively, control is performed to transfer the pseudo code 542 stored in the area C, and control is performed to transfer the vehicle-specific code 54 stored in the storage area A of the storage unit 168 when the wireless transmission / reception unit 162 is activated.

Next, with reference to FIGS. 6 to 8, the mobile communication system in this embodiment and the operation and operation of the on-board radio in the mobile station will be described. FIG. 6 is a diagram showing an example of a frame format, FIG. 7 is a flowchart for explaining the operation of the vehicle-mounted device 160, and FIG. 8 is a diagram showing an example of a communication sequence.

Communication between the mobile station 16 and the base station 10 is performed by boring in a frame 100 having a format as exemplified in FIG. In this embodiment, the frame 100 has a period of 683 milliseconds (ms) and a transmission speed of 512 Kbit / sec, and a plurality of channels are multiplexed in a number of time slots included in the frame. In principle, required bidirectional communication is completed within this one frame period. A single frequency is used for the radio wave 18 of the wireless link. In the case of full-duplex communication, a pair of frequencies that are different from each other at the top and bottom are used. However, their frequency may be fixed, and the
The same frequency is used even if moves.

At the beginning of the frame 100 is an introductory part 102, which is
A preamble, a synchronization signal, a boring identification signal, a code of the road station 10, and the like are included. Road station 10 using this
Boring at a predetermined period to the mobile station 16 in the zone 20, as shown in FIG.

In this case, the mobile station 16 performs the operation shown in FIG. 7 in advance when the power of the vehicle-mounted device 160 is turned on. When the power is turned on (step ST1), the controller 172
Reads the time at that time from the clock unit 170, reads the mobile station code 540 from the area B of the storage unit 164, and compares the mobile station code 540 and the time with the pseudo code generation unit 170.
(Step ST2). The pseudo code generation unit 170
When the power is turned on, a random number is generated, and a pseudo code 5 is generated based on the random number, the transferred time and the mobile station code 540.
42 is generated (step ST3). When the pseudo code 542 is generated by the pseudo code generation unit 170, the control unit 172 stores the code in the area C of the storage unit (step ST4). In this state, when the mobile station 16 enters the transmission mode, the control unit 172 reads the state of the mode changeover switch 166 (step ST5) and makes the determination (step ST6). When the communication mode is set to be performed, the mobile station code 540 in the area B is changed to the area A.
(Step ST7). When the mode changeover switch 166 is in the non-communication mode in which communication with the automatic vehicle operation system is not performed, the pseudo code
Is read and written in the area A (step ST8).

The mobile station 16 is in the reception mode in the idle state, and
When the reception of 102 is completed, the mode is set to the transmission mode.

Referring again to FIG. 6, the introduction unit 102 is followed by the vehicle recognition unit 104.
This is a period during which the mobile station 16 transmits the static code 50 and the dynamic code 60 including the vehicle-specific code 54 in response to the bowling, and the road station 10 recognizes this. Advantageously, by performing the two-block repetitive transmission, the recognition rate of the joining vehicle 12 is significantly improved.

The mobile station 16 selects an available free channel from the plurality of channels from the random number table in response to the bowling. This channel is used to transmit the static code 50 or the service function code to the road station 10.

The road station 10 receiving these codes transfers the data to the road-to-vehicle information center 26 via the network 22.

The road-to-vehicle information center 26 grasps the position of the vehicle from these codes and records the position information in a database.

In this embodiment, following the vehicle recognition unit 104, the broadcast communication unit 106
, And beacon-type dynamic navigation information such as traffic information and a registration response signal (ACK or NACK) are transmitted from the road station 10 to the mobile station 16.
Therefore, at the time of communication of the isotropic communication unit 106, even when the mobile station code 540 unique to the on-vehicle device 160 is used,
It can be used even when the pseudo code 542 is used.

If the channel selected by the mobile station 16 does not collide with another,
This is registered in the road station 10 and an ACK signal is transmitted to the mobile station 16.

This is followed by the vehicle communication unit 108, whereby, in the present embodiment, full-duplex communication is performed between the road station 10 and the mobile station 16 as shown in FIG. The frequency differs between the upper and lower sides, and the channel selected by the road station 10 is used.
However, even if the joining vehicle 12 moves to the zone 20 of the adjacent road station 10, the same frequency is used. Of course, half-duplex or one-way communication may be used.

In the vehicle communication unit 108, data such as navigation information and operation management information between the mobile station 16 and the user center 28,
Messages and image signals are transmitted and received, and the information is displayed to the passengers of the subscribing vehicle 12 by images and sounds. In this case, the user center 28 obtains, from the road-to-vehicle information center 26, position information on the mobile station code 540 of the specific vehicle such as its own vehicle and other traffic information, and the like.
Use 8 to communicate.

Communication with the general telephone line network 24, the data exchange network 25, or another mobile station 16 in the present system may be performed in the same manner.

In the road station 10, the zone is thus set for each boring cycle.
The data of the subscribing vehicle 12 obtained from the mobile station 16 in 20 may be stored in the communication vehicle table 82. The road station 10 transfers these data to the regional station 30, the regional station 32, or the general office 34 via the line 36.

In these stations, such transferred data is stored, for example, in the traveling vehicle table 80. Thus, for example, the traveling vehicle table 80 of the regional station 32 is constantly updated with new data.

Information addressed to the mobile station 16 from the centers 26 and 28, the general telephone line network 24, and the data exchange network 25 is temporarily stored in one of these stations, for example, the memory 42 of the road station 10. Road station
At 10, the static code 50 obtained from the mobile station 16 in the service area is compared with the destination code of the transmission information to check whether there is information to be transmitted to the corresponding mobile station 16 or not. When a match is detected, the information stored in the memory 42 is transmitted to the mobile station 16 using the downlink channel of the vehicle communication unit 108.

Information transmitted from the mobile station 16 by the uplink channel,
It is temporarily stored in the memory 42. This upstream transmission information is later transferred to the centers 26 and 28, the data exchange network 25 or the general telephone network 24 via the road-to-vehicle individual communication network 22.

When the vehicle communication unit 108 ends, the upper and lower response signals (eighth
This is followed by a communication completion unit 110 for transmitting (FIG.). This is a signal for confirming the completion of the transmission, not for confirming the information content.

Thus, communication of one frame 100 is performed while the subscribing vehicle 12 is traveling in the service zone 20 of the road station 10. The mobile station 16 cannot communicate with the road-to-vehicle individual communication network 22 while the joining vehicle 12 is traveling in the non-radio wave area between two adjacent zones 20. By using a single frequency, a conventional leaky coaxial cable broadcasting system may be envisioned. However, this embodiment is not a broadcasting system but an individual communication system to the last, and is fundamentally different from a leaky coaxial cable broadcasting system in that there is no radio wave area.

In this embodiment, in principle, the minimum zone in which the
It is configured such that one communication is completed while being included in 20. Regardless of whether it is an ordinary road or an expressway, as long as the vehicle is traveling normally on the road, the joining vehicle 12 envisions several minimal zones 20 across the above-mentioned anechoic region, so that it can be considerably organized. The road station 10 is disposed on the road at intervals such that communication can be performed. In other words, such a separated arrangement of the on-road stations 10 can sufficiently achieve required communication even with the mobile station 16 having a lot of communication traffic.

The embodiment in which the present invention is applied to the road-to-vehicle individual communication system has been described. However, the present invention is not limited to this, and is effectively applied to individual communication with any mobile object other than a vehicle, for example, an individual, that is, a pedestrian in a broad sense.

It should be noted that the embodiments described here are for describing the present invention, and the present invention is not necessarily limited thereto. Modifications and variations that can be made by those skilled in the art without departing from the spirit of the present invention. Modifications are included in the scope of the present invention.

(Effects of the Invention) As described above, the mobile station that communicates with the mobile communication system of the present invention and a system other than the on-board radio and the traffic flow grasping system in the mobile station uses the switch means of the on-board radio In the communication mode, the unique code assigned to the radio is transmitted to the fixed station in each communication area where the fixed station is located, and the location is notified to the traffic flow grasp system, and the detection result The individual communication with the operation management system or the like can be efficiently performed based on the information.

Also, a mobile station that communicates only with the traffic flow grasping system, if the switch means of the onboard radio is set to the non-communication mode, a pseudo code masked with a random number in each communication area where the fixed station is located. Is transmitted to the traffic flow grasping system to notify its location, so that only the position information is detected, so that the detection of the own station by other systems or the like can be prevented, and privacy protection can be secured.

[Brief description of the drawings]

FIG. 1 is a conceptual block diagram showing an embodiment in which a mobile communication system according to the present invention is applied to road traffic of vehicles as a road-vehicle individual communication system, and FIG. 2 is a road-vehicle communication system in the embodiment shown in FIG. FIG. 3 is a diagram showing an example of a station hierarchy configuration of an individual communication network, FIG. 3 is an explanatory diagram showing an example of a format of a vehicle-specific code in the embodiment, and FIG. FIG. 5 is a conceptual diagram showing a pseudo code generation process in the embodiment, FIG. 6 is an explanatory diagram showing an example of a frame format in the embodiment, and FIG. FIG. 8 is a flowchart showing the operation of the apparatus, and FIG. 8 is a sequence diagram showing a communication sequence between the mobile station and the fixed station in the embodiment. Description of Signs of Main Parts 10 Road Station 12 Subscribing Vehicle 14 Transceiver 16 Mobile Station 20 Minimal Zone 22 Road-to-Vehicle Individual Communication Network 42 Memory 80 Vehicle Table 82: Passing vehicle table 160: On-vehicle device 162: Wireless transmission / reception unit 164: Storage unit 166: Mode switch 168: Pseudo code generation unit 170: Clock unit 172: Control unit 540: Mobile station Code 542 …… Pseudo code

Claims (4)

(57) [Claims] 1. A fixed station is arranged at a predetermined interval along a path of a mobile unit to form an intermittent communication area, and the fixed station transmits a radio signal transmitted from the mobile station in the communication area. A traffic flow grasping system for detecting position information of each mobile station by receiving a signal and measuring the traffic flow thereof, based on the position information of the mobile station detected by the traffic flow grasping system, In a mobile communication system applied to a mobile station and another system other than the traffic flow grasping system that performs communication via the fixed station, the mobile station transmits to the radio when the power of the radio mounted on the radio is turned on. When a pseudo code different from the assigned unique code is generated and communication is performed with a system other than the traffic flow grasping system, the unique code assigned to the on-board radio is transmitted in the communication area of the fixed station. Transmitting a pseudo code generated at power-on in the communication area of the fixed station as a radio signal from the transmitting unit when transmitting only the traffic flow grasping system. Mobile communication system. 2. The mobile communication system according to claim 1, wherein the traffic flow grasping system includes a unique code assigned to each of the mobile stations or a pseudo code generated by each of the on-board radios when power is turned on. A mobile communication system characterized by detecting position information of each mobile station by receiving one of them by each fixed station and grasping a traffic flow. 3. The mobile communication system according to claim 2, wherein a system other than the traffic flow grasping system detects a unique code assigned to the mobile station by the traffic flow grasping system. A mobile communication system characterized by communicating with a corresponding mobile station via each fixed station. 4. A fixed station is arranged at a predetermined interval along a path of a mobile unit to form an intermittent communication area, and the fixed station is transmitted from each mobile station in these communication areas. Receiving a wireless signal to detect the position information of each mobile station, and measuring the traffic flow of the mobile station, based on the position information of the mobile station detected by the traffic flow detection system. An on-board radio of a mobile station in a mobile communication system applied to the mobile station and another system other than the traffic flow grasping system for performing communication via the fixed station; A pseudo-code generating means for generating a pseudo-code based on the random number, the power-on time, and the unique code assigned to the wireless device. Storage means for respectively storing a pseudo code and the unique code; a communication mode for communicating with a system other than the traffic flow grasping system; and a switch means having a non-communication mode for communicating only with the traffic flow grasping system. Judging the state of the switch means, when the mobile station passes through the communication area of the fixed station, if the switch means is in the communication mode, the unique code stored in the storage means Read out and transmit the unique code as a wireless signal from the transmitting unit, and when the switch unit is in the non-communication mode, read the pseudo code stored in the storage unit and use the pseudo code as a wireless signal from the transmitting unit. An on-board radio in a mobile station, comprising: a control unit for transmitting.