JP2670085B2 - Mobile communication system - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a mobile communication system, and more particularly to a mobile communication system suitable for communication with a vehicle such as an automobile.

(Prior Art) As a conventional mobile communication system to which the present invention is particularly relevant, there is, for example, a car telephone system. As is well known, in a conventional car telephone system, base stations covering a predetermined service zone are two-dimensionally arranged, and the zones of adjacent base stations partially overlap with each other.
Some mobile phones adopt a cellular system that guarantees continuity of communication with a mobile body.

When terminating a mobile station, it is necessary to identify the current location of the mobile. In the conventional cellular car telephone system, each time a call is received by a mobile station, a simultaneous call is made from the network side to a plurality of zones, and a response from the mobile station to the call is detected to grasp the current position and establish a call connection. I was doing.

(Problems to be Solved by the Invention) In the cellular system, different frequencies are used between a plurality of adjacent zones, that is, cells, in order to avoid radio wave interference. In order to effectively use the limited frequency band, it is preferable to subdivide the zone structure and repeatedly use the same frequency. However, the subdivision of the zone structure increases the frequency of frequency switching accompanying movement across the zones, and imposes a frequency switching control burden on both the base station and the mobile station. This tendency becomes more remarkable as the moving speed of the moving body increases. In order to solve this problem, it has been necessary in the conventional cellular system to widen each zone or increase the allocated frequency. However, as is well known, increasing the frequency allocation is very difficult.

The conventional cellular car telephone system is designed mainly for voice communication, and is not necessarily suitable for the service purpose of transmitting a large amount of data at high speed. For example, in the case of land transportation such as automobiles, in order to efficiently manage the navigation that guides the route to an appropriate route according to the road congestion and weather conditions, and the efficient management of the operation of many vehicles, It is necessary to transmit a large amount of data at high speed. The conventional car telephone system is not necessarily suitable for various services including such high-speed data communication because the frequency of the transmission signal is limited to the voice band.

In addition, each time a call is received, a paging call is made from each base station, and the mobile station responds to the incoming call before making a call connection. Therefore, connection control of the call is complicated, and a relatively long connection setup time is required. It was Further, since the current position of the mobile unit cannot be known unless the mobile station individually receives a call, a user having a large number of vehicles such as a carrier is not suitable for efficiently managing the operation of those vehicles. .

Therefore, multiple base stations wirelessly linked to the mobile station
If base stations are spaced apart from each other with a no-radiation area interposed between them, these base stations will be able to use a single frequency as the radio wave of the radio link. In such a mobile communication system, the base station that can communicate with the mobile station changes with the movement of the mobile station. Therefore, in order to properly communicate with the target mobile station, the system must be the current mobile station. It is necessary to keep track of the position.

In view of the demand for such mobile communication, the present invention has
An object of the present invention is to provide a mobile communication system capable of appropriately managing the state of a mobile station including communication with the mobile station.

(Means and Actions for Solving the Problems) According to the present invention, in a mobile communication system including a mobile station and a plurality of ground stations forming a communication circuit network for communicating with the mobile station, the mobile station Is registered with any of a plurality of ground stations, and when any of the plurality of ground stations detects a mobile station, the mobile station notifies the location of the mobile station among the plurality of ground stations to which the mobile station is registered. The earth station with which the mobile station is registered stores the notified position of the mobile station. By detecting and notifying the position of the mobile station, the stored contents of the earth station with which the mobile station is registered are constantly stored. Will be updated.

For example, when communicating with a mobile station, the location stored for the mobile station is obtained at the ground station to which the mobile station associated with the communication is registered. Then, it communicates with the mobile station through a ground station near this location. Thus, as long as the target mobile station is active, appropriate management of the mobile station including communication with the mobile station is always possible.

(Example) Next, an example of a mobile communication system according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 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 an individual road-vehicle communication system. In this embodiment, a plurality of roadside stations 10 are normally arranged along a general road or a highway at a predetermined interval, for example, several hundred meters to several kilometers. This interval may be set to an appropriate value according to the vehicle speed allowed on the road, for example. The roadside station 10 is a ground station that functions as a base station that wirelessly communicates with a subscribing vehicle 12 on the road.

The roadside station 10 has a transmitter / receiver 14, which transmits and receives radio waves 18 to and from a mobile station mounted on the subscribing vehicle 12, that is, a vehicle-mounted device 16 (FIG. 3), and its service area or zone.
It communicates with the vehicle 12 present in 20. One of the characteristics of this embodiment is that the size of the zone 20 is much smaller than the arrangement interval of the roadside stations 10 and the roadside stations 10 are intermittently arranged. Its diameter may be, for example, on the order of tens of meters to 100 meters. Therefore, between two adjacent zones 20, there is a region where the mobile station 16 does not substantially respond to the radio waves transmitted by the roadside station 10, that is, a "no radio wave region", and the vehicle 12 is included in the zone 20. It is possible to communicate with the roadside station 10 only while it is present. This communication is performed at high speed.

As can be seen, in this system, the neighboring road station
The same frequency can be used repeatedly and effectively for 10. Therefore, it is basically sufficient for the radio link between the roadside station 10 and the mobile station 16 to use a single frequency throughout the system. In the case of a system that enables full-duplex communication, a pair of frequencies that are different from each other above and below are used. This eliminates the need for frequency zone switching as in the conventional cellular system. Due to these characteristics, this method is called "intermittent minimum zone method", and the zone 20 is called "minimum zone".

The road station 10 constitutes a part of the road-to-vehicle individual communication network 22,
In this embodiment, the general telephone line network 24,
It is possible to access other communication facilities such as a data switching network 25 such as a general packet switching network, a system center 26 and a user center 28. In the present embodiment, the road-to-vehicle individual communication network 22 has a station-level structure as illustrated in FIG.
General telephone line network 24, data exchange network 25 and centers 26, 28
A communication network for performing switching, that is, switching between the mobile station 16 and the mobile station 16. This will be described later in detail.

In such an intermittent minimum zone system, communication between the mobile station 16 and the roadside station 10 can be speeded up, and various services including high speed data communication can be provided. For example,
Via a road-to-vehicle individual communication network 22, for the purpose of navigation for guiding the participating vehicles 12 such as automobiles to an appropriate route according to road congestion and weather conditions, and to efficiently manage the operation of a large number of vehicles 12. Data communication can be performed between the centers 26 and 28 and the mobile station 16.

Referring to FIG. 3, the road-to-vehicle individual communication line network 22 in this embodiment is composed of a plurality of road stations arranged in a certain area.
It has a hierarchical structure composed of a district station 30 in which 10 are accommodated, a regional station 32 in which a plurality of district stations 30 are accommodated over an area, and a general station 34 in which several of these regional stations 32 are accommodated. These exchanges 30, 32, 34 including the roadside station 10 are referred to as ground stations. In the present embodiment, the line between the district station 30, the regional station 32, and the general control station 34 forms a tree-like network composed of trunk lines 36 such as trunk lines and diagonal lines. Type network. The present invention is not limited to this network form, and it goes without saying that, for example, 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 may be taken. Yes.

The trunk line 38 for the general public telephone line network 24 and the data exchange network 25 is accommodated in the general bureau 34, for example. The system center 26 is, for example, an information processing system that processes the navigation of the joining vehicle 12. User Center 28
Is an information processing system for independently managing the operation of the belonging vehicles 12 belonging to a specific user. 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 general bureau 34 and the regional station 32 among them in the station level structure, the registered ground station code 52 (FIG. 4) for identifying the regional station 32 is formed. For a large user's subscribed vehicle 12 having a large number of subscribed vehicles 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, for example, the regional station 32, and a unique mobile station code 54 is assigned to the regional station 32. Therefore, nationwide, the on-vehicle device, that is, the mobile station 16 is specified by the ground station code 52 and the mobile station code 54.
The joining vehicle 12 may be registered in the general bureau 34 or the district bureau 30.

The identification code for identifying the mobile station 16, that is, the vehicle-specific code is composed of a static code 50 and a dynamic code 60 in this embodiment as shown in FIG. The static code 50 is the local station 32
The code is a code that identifies the mobile station 16 registered in, and includes a ground station code 52 and a mobile station code 54, and a system code 56 for identifying this 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.
Therefore, in addition to the function as the identification number of each mobile station 16 inside the system, the static code 50 is added to the mobile station 16 from the general telephone line network 24, the data exchange network 25 or the centers 26 and 28. Has a close relationship with the numbering system.

The mobile station 16 of the joining vehicle 12 has a vehicle code generator 130 (third station).
), Which is the functional part that generates the vehicle code assigned to that mobile station 16. This vehicle code contains
It includes a ground station code 52 that identifies the registration station with which the mobile station 16 was originally registered, and a mobile station code 54 of the mobile station 16. These codes are set in the vehicle code generator 130, and are read and transmitted in response to polling from the roadside station 10 described later.

For example, as shown in FIG. ₁ , it is assumed that the mobile station 16 in _one regional station B ₁ accommodated in the general bureau A ₁ is registered. The ground station code 52 that identifies the regional station 32 is "A
₁ B ₁ ”, and the mobile station code 54 of the mobile station 16 in the regional station is“ M ₀₃ ”, the mobile station is identified by the static vehicle code“ A ₁ B ₁ M ₀₃ ”. It

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
It is a vehicle-specific code related to the driving place area and movement situation of the general telephone line network 24, data exchange network 25, center 26,
Search for vehicle location for individual communication from 28, joined vehicle 12
Plays an important role in providing route guidance information to other travel destinations. 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. Driving area code 64
In this embodiment, is composed of station codes of the general bureau 34, the regional office 32, the district office 30 and the roadside office 10. In addition, a link code for specifying the set communication link may be included.

In this 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. Similar vehicle tables may be provided in, for example, the district office 30 and the general bureau 34.

As conceptually shown in FIG. 2, the roadside station 10 is provided with a memory 42, which includes a passing vehicle table 82 (FIG. 3),
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 vehicle specific codes 50 and 60,
It is constantly updated with the passage of the subscribing vehicle 12.

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, it is provided with a video display, a facsimile transmitting / receiving device, a voice synthesizing device, and the like that interface with the passengers by images and voice. 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 in response to polling from the roadside station 10, an available free channel is selected by the roadside station 10 out of a plurality of channels in the link 18 with the roadside station 10. It

Communication between the mobile station 16 of the subscribing vehicle 12 and the base station 10 is carried out by polling with a frame 100 having a format as shown in FIG. 5 in this embodiment. In this embodiment,
Frame 100 has a period of 683 milliseconds (ms) and a transmission speed of 512K
At bits per second, multiple channels are multiplexed into the multiple timeslots they contain. In principle, required bidirectional communication is completed within this one frame period. A single frequency is used for wireless link 18. 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, those frequencies may be fixed, and the same frequency is used regardless of which on-road station 10 zone 20 the joining vehicle 12 moves to.

At the beginning of the frame 100 is an introductory part 102, which is
It includes a preamble, a synchronization signal, a polling identification signal, a code of the roadside station 10, and the like. Road station 10 using this
Polls the mobile station 16 in the zone 20 at a predetermined cycle, as shown in FIG. The mobile station 16 is in the reception mode in the idle state, and is in the transmission mode after the reception of the introduction unit 102 is completed.

The introduction 102 is followed by the vehicle recognizer 104, which includes the vehicle-specific codes 50 and 60 in response to the mobile station 16 polling.
Is transmitted, 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 one of the plurality of channels from the random number table in response to the polling. In response to the polling, the vehicle code generator 130 of the mobile station 16 generates the registered ground station code 52 and mobile station code 54 of the mobile station 16 set therein, and statically uses this channel. It is transmitted to the road station 10 as a vehicle specific code 50 or a service function code (see FIG. 6).

For example in the example of Figure 1, housed local station A ₀ B ₁ housed in which one of the eight paths station 10 to the district station C ₁ to is the station in which the code D ₀ to D ₇ are assigned respectively And The sixth road station 10 from the left in the figure is designated by the station code “A ₀ B ₁ C ₁ D ₅ ”. In this example, the mobile station 16 having "A ₁ B ₁ M ₀₃ " as the static vehicle code 50 is a roadside station A ₀ B ₁ C.
_When being polled while passing through the ₁ D ₅ zone 20, the mobile station 16 returns the identification code "A ₁ B ₁ M ₀₃ " as the ground station code 52 and the mobile station code 54.

The mobile station 16 travels in the direction of the arrow, and the next road station A ₀ B ₁ C ₁ D ₆
When the mobile station 16 enters the zone 20 of the road station A ₀ B ₁ C ₁
Polling is performed from D _{6 in the} same manner as above, and the vehicle code “A ₁ B ₁ M ₀₃ ” is returned. In this way, with the movement of the mobile station A ₁ B ₁ M ₀₃ , the sequential road stations 10 on the course receive the vehicle code “A ₁ B ₁ M ₀₃ ” from the mobile station A ₁ B ₁ M ₀₃ one after another. .

Returning to FIG. 5, in the present embodiment, the broadcast communication unit 106 is arranged following the vehicle recognition unit 104, and using this, the beacon type dynamic navigation information such as traffic information from the roadside station 10,
And a registration response signal (ACK or NACK) is transmitted to the mobile station 16. If the channel selected by the mobile station 16 does not collide with others, it is registered in the roadside station 10 and an ACK signal is transmitted to the mobile station 16.

After that, the vehicle communication unit 108 follows, and in this embodiment, full-duplex communication is performed between the roadside station 10 and the mobile station 16. The frequencies are different from each other in the upper and lower sides, and the channel designated by the roadside 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, the mobile station 16 and the system center 26
Data such as navigation information and operation management information, messages and image signals are transmitted and received to and from the user center 28, and the information is displayed to passengers of the subscribing vehicle 12 as images and voice. Further, communication with the general telephone line network 24, the data exchange network 25, or another mobile station 16 in the present system is similarly performed.

In the road station 10, the zone is thus set for each polling cycle.
The data of the joining vehicle 12 obtained from the mobile station 16 in 20 may be held in the passing 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, the data thus transferred is stored, for example, in the traveling vehicle table 80.
Thus, for example, the traveling vehicle table 80 of the regional station 32
It is constantly updated with new data.

More specifically, as shown in FIG.
Includes a ground station code 52 that identifies the regional station 30 and a station code generator 132 that generates a road station code that identifies the on-road station 10 in the area. For example, the district office A ₀ B in FIG.
₁ C ₁ is sent to the station code generation unit 132 as the ground station code 52, and "A ₀
B ₁ C ₁ "is set. The vehicle code “A ₁ B ₁ M ₀₃ ” of the mobile station 16 received by the road station A ₀ B ₁ C ₁ D ₅ is temporarily stored in the passing vehicle table 82 of the road station 10, and the higher-order regional station A ₀ B ₁
Transferred to C ₁ . As shown in FIG. 6, the district bureau A ₀ B ₁ C ₁
From this vehicle code “A ₁ B ₁ M ₀₃ ”, the registration bureau becomes the general bureau A ₁
It identifies the local station A ₁ B ₁ belonging to the local station A ₁ B ₁ and transfers the vehicle code “A ₁ B ₁ M ₀₃ ” to the regional station A ₁ B ₁ . On this occasion,
The district station A ₀ B ₁ C ₁ transmits its own station and the location information of the on-road station 10 that has detected the mobile station 10 as information indicating the current location of the mobile station 16. This location information includes its ground station code "A ₀ B ₁ C ₁ " and roadside station code "D ₅ " in the form of a driving area code 64 of the dynamic vehicle code 60.

An exchange higher than the district office A ₀ B ₁ C ₁ , for example, the regional office A ₀
B ₁ and the general bureaus A ₀ and A ₁ identify their destinations based on the vehicle code “A ₁ B ₁ M ₀₃ ” of the mobile station position data to be transferred, and their registration stations, that is, regional stations A _{1 in} this example. to relay it towards the B _1. Registration station A ₁ B ₁ is mobile station position data,
That is, when the static vehicle code 50 and the dynamic vehicle code 60 are received, the target mobile station 16, that is, the station M ₀₃ in this example, is identified from the mobile station code 54, and corresponding to that of the traveling vehicle table 80. These location data are stored in the storage location to be used.

The current position data of the mobile station 16 is constantly updated. Focusing on a specific mobile station, for example, M ₀₃ , its position data is, for example, from the regional station 30 to the registration station A ₁ as described above every time one of the roadside stations 10 detects the mobile station M _03.
Reported to B ₁ , the memory content of mobile station M ₀₃ in traveling vehicle table 80 is updated.

In this embodiment, each time the mobile station 16 moves over the two roadside stations 10, the location is reported to the registration station. In that case,
The traveling area code 64 as the current position data to be reported to the registration station may include a roadside station code, “D ₅ ” in this example. For example, when mobile station A ₁ B ₁ M ₀₃ moves from zone 20 of road station A ₀ B ₁ C ₁ D ₅ to zone 20 of adjacent station A ₀ B ₁ C ₁ D ₆ , the latter road station A ₀ B ₁ C ₁ D ₆ detects this by polling, stores the mobile station code “A ₁ B ₁ M ₀₃ ” in the passing vehicle table 82, and reports this to the regional station A ₀ B ₁ C ₁ . District Office A ₀
B ₁ C ₁ is the traveling area code “A ₀ B ₁ C ₁ including the road station code“ D ₆ ”as new position information of this mobile station A ₁ B ₁ M _03.
D ₆ ”to Registration Authority A ₁ B ₁ . This method has a relatively large processing load on the communication traffic for reporting the current position of the mobile station 16 and its updating and holding at the registration station.
It has the advantage that the current position of is always measured accurately.

Instead, if any district station 30 detects a specific mobile station M ₀₃ for the first time via the on-road station 10 in its jurisdiction, it is configured to report this to the registration station A ₁ B _1. Good. In that case, the traveling area code 64 does not include the road station code and may be up to the district station code. For example, the mobile station A ₁ B ₁ M ₀₃ continues to run, passes through the roadside station A ₀ B ₁ C ₁ D ₇ at the end of the regional station A ₀ B ₁ C ₁ , and then moves to another adjacent regional station A ₀ B ₁ C ₂ 's first road station A ₀ B ₁ C ₂
And it went into the zone 20 of the D _0. This road station A ₀ B ₁ C ₂ D
₀ indicates the vehicle code 50 of the mobile station A ₁ B ₁ M ₀₃ as the upper district station.
Report to A ₀ B ₁ C ₂ and the district office will pass this.
Register with. At that time, the regional office will use this vehicle code "A ₁
B ₁ M ₀₃ ”is stored in the passing vehicle table 82 so far. If it is determined that it has not been stored, the current position data is transferred to the registration station A ₁ B ₁ through the higher-level regional station A ₀ B ₁ . In this case, the station code "A ₀ B ₁ C ₂ " up to the district station 30 is sufficient as the current position data. In this method, communication traffic for reporting the current position of the mobile station 16 can be reduced, and the process of managing the traveling position in the registration station can be simplified.

Information addressed to the mobile station 16 from the centers 26, 28, the general telephone network 24, and the data exchange network 25 is temporarily stored in the memory 42 of any ground station, for example, the roadside station 10. In the roadside station 10, the static vehicle specific code 50 obtained from the mobile station 16 in the service area
And the destination code of the transmission information are compared, and the corresponding mobile station
Check if there is any information to send to 16. When a match is detected, the information stored in the memory 42 is transmitted to the mobile station 1 using the downlink channel of the vehicle communication unit 108.
Send to 6. The information transmitted from the mobile station 16 through the uplink channel is temporarily stored in the memory 42. This upstream transmission information is later transmitted to the center via the road-to-vehicle individual communication network 22.
26, 28, data exchange network 25 or general telephone network 24.

When the vehicle communication unit 108 ends, the communication completion unit 110 that transmits upper and lower response signals follows. 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 a general road or an expressway, as long as the vehicle is traveling normally on the road, the joining vehicle 12 travels in some minimal zones 20 across the above-mentioned anechoic region, and thus is considerably cohesive. Road stations 10 are arranged along the road at intervals such that communication can be performed. In other words, such a spaced arrangement of the on-road station 10 can sufficiently achieve the required communication even for the mobile station 12 having a large amount of communication traffic.

By the way, using the mobile station position data that is constantly updated by the registration station A ₁ B _1, the mobile station A ₁ B ₁ M
_The sequence for arriving at ₀₃ will be schematically described with reference to FIG. A message addressed to the mobile station A ₁ B ₁ M ₀₃ from the center 26 or 28 is routed through the general station 34 with a header in the form of a static vehicle specific code 50 containing its destination code "A ₁ B ₁ M ₀₃ ". To the registration bureau A ₁ B ₁ . This message transfer is performed at each relay station with the destination code "A ₁ B
₁ M ₀₃ ”by identifying. Registration Authority A ₁ B ₁
Receives this message together with the header, checks the registration qualification of the mobile station A ₁ B ₁ M ₀₃ to be received from the destination code, and temporarily stores the message in a memory (not shown) if satisfied. Accumulate (140). Although not shown in the figure, the registration station A ₁ B ₁ returns a reception confirmation response to the center 26 or 28 at this time.

Therefore, the registration station A ₁ B ₁ refers to the traveling vehicle table 80,
The current position of the called mobile station A ₁ B ₁ M ₀₃ is checked from the mobile station position data. As a result, the current position of mobile station A ₁ B ₁ M ₀₃ is
For example, if it turns out to be "A ₀ B ₁ C ₁ D ₅ ", the registration authority A ₁ B ₁
From this, the dynamic vehicle specific code 60 including the address “A ₀ B ₁ C ₁ ” of the district station 30 as the traveling area code 64 is created. Registration station A ₁ B ₁ reads the transmitted message from memory and adds the dynamic code 60 to its header to add to district station A ₀ B ₁ C ₁
Send to.

Relay stations, such as general bureau 34 and regional office 32, identify the dynamic vehicle-specific code 60 in a message and
Transferred to the A ₀ B ₁ C _1. When the district station A ₀ B ₁ C ₁ receives this message together with the header, it broadcasts to all the roadside stations 10 accommodated in it. This broadcast includes the delivery request, the message, and the destination code “A ₁ B ₁ M ₀₃ ” of the message. Upon receiving this, each roadside station 10 temporarily stores the message in the memory 42, and at the same time, stores it in the service zone.
Poll mobile stations 16 contained within 20. This polling is performed by the introduction unit 102 of the frame 100 as described above.

In response to this polling, the active mobile station 16 included in the service zone 20 of the roadside station 10 generates the vehicle codes 50 and 60 in the vehicle code generation unit 130 and returns the vehicle codes 50 and 60 to the roadside station 10. The vehicle recognition unit 104 is used for this.
Street station 10 temporarily stores the passing vehicle table 82 the vehicle code sent back from the mobile station 16, it compares the static vehicle specific code 50 of them destined code of the message "A ₁ B ₁ M _03" (142 ). When the two match at any of the roadside stations 10, the station 10 reads the transmission message from the memory 42 and transmits it using the vehicle communication unit 108 on the channel of the mobile station A ₁ B ₁ M ₀₃ . Mobile station A ₁ B ₁ M ₀₃ that received the message
Returns a reception confirmation response using the communication completion unit 110, and this is finally transferred to the registration station 34 via the ground station. If the acknowledgment includes an acknowledgment ACK, the local station A ₀ B
₁ C ₁ cancels the delivery request to another road station 10.

Under the control of the district station A ₀ B ₁ C ₁ , the remaining road station 10 for which the vehicle code does not match in step 142 discards the message stored in the memory 42 and ends this processing. Although each station returns an acknowledgment at each stage of the mobile station incoming sequence, this is not shown in FIG. 7 in order to avoid complication of the figure.

In summary, in this embodiment, each mobile station 16 is registered in advance with a specific ground station. The registration station is notified of its current position by the ground station that has detected the mobile station 16 registered therein, and holds the current position data. This current position data is constantly updated in real time. When receiving an incoming call to the mobile station 16, the registered station of the mobile station 16 is accessed to obtain its current position, and the roadside station 10 in the vicinity thereof is accessed.
Makes an incoming connection to the mobile station 16.

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.

(Effect of the Invention) In the mobile communication system according to the present invention, a mobile station is registered in a specific ground station, and the current position of the mobile station, which changes moment by moment, is managed by the registration station. As a result, as long as the target mobile station is active, appropriate management of the mobile station including communication with the mobile station is always possible.

For example, compared with the conventional car telephone system, since there is no simultaneous call from each base station, the connection control of incoming calls is simple and the connection setup time is short. In addition, since the current position of the moving object is constantly grasped, for example, a large user or the like, in response to a request to know the traveling position of many vehicles in real time for the purpose of efficient operation management, a network service is required. Can handle.

[Brief description of the drawings]

FIG. 1 is an explanatory view conceptually showing a mobile communication system according to the present invention, and FIG. 2 is a concept showing an embodiment in which the mobile communication system according to the present invention is applied to road traffic of a vehicle as an individual road-vehicle communication system. FIG. 3 is a relay block diagram showing an example of the station level structure of the road-to-vehicle individual communication line network in the embodiment shown in FIG. 2, and FIG. FIG. 5 is an explanatory diagram showing an example of a frame format in the same embodiment, FIG. 6 is a sequence diagram showing an example of a sequence for detecting the position of a mobile station in the same embodiment, and FIG. FIG. 9 is a sequence diagram showing an example of an incoming sequence to a mobile station. Explanation of symbols of main parts 10 …… Road station 12 …… Joined vehicle 14 …… Transceiver 20 …… Minimum zone 22 …… Road-to-vehicle individual communication network 30,32,34 …… Exchange station, ground station 42 …… Memory 80 …… Traveling vehicle table 82 …… Passing vehicle table 130 …… Vehicle code generator 132 …… Station code generator

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-59-133742 (JP, A) JP-A-62-7230 (JP, A) JP-A-61-293033 (JP, A) JP-A-59- 182649 (JP, A) Japanese Patent Laid-Open No. 58-60841 (JP, A) Sadao Ito, Hata Matsuzaka "Outline of Car Telephone System" pp. 1826-1829, Research Practical Report Vol. 26, No. 7, July 22, 1977, Nippon Telegraph and Telephone Public Corporation Musashino Electro-Communications Research Laboratories

Claims (1)

(57) [Claims] A communication line for exchanging communications with a plurality of base stations, each of which communicates with a mobile station via a radio link, and a local station accommodating each of the plurality of base stations in a plurality of units. A plurality of regional stations that form a network; and a plurality of exchange stations that form the communication line network that accommodates the plurality of regional stations and exchanges communications with the plurality of regional stations; Among them, those that are close to each other are spaced apart from each other by interposing a region where the mobile station does not substantially respond to the radio wave of the wireless link, and the mobile station is located at any of the plurality of exchanges, In a mobile communication system registered in association with an identification code that identifies the mobile station, the mobile station responds to polling from the base station, and the identification code includes a mobile station code assigned to itself. The When the local station transmits the identification code from the mobile station via the base station, the district station detects the registered exchange of the mobile station from the identification code, and the mobile station uses the identification code. The district exchange code of the district station and the base station code of the base station are added as information indicating the location of the information, and the information is transferred to the registration exchange. The registration exchange to which the identification code is transferred is A mobile communication system wherein a base station code is stored in correspondence with an identification code of the mobile station, and the storage contents of the registered exchange are constantly updated by detection and notification of the position of the mobile station.