JPH01311631A - System for detecting position of mobile station in mobile body communication - Google Patents

Abstract

PURPOSE:To reduce communication traffic for the notice of a present location and to prevent the communication traffic for regular information from being blocked by limiting the notice of the present location only to a time when a mobile station is detected first in a prescribed area. CONSTITUTION:An individual mobile station 16 is registered on a specific ground station (a section station 30, an area station 32, or a general station 34) in advance. The ground station 30, when detecting the mobile station 18 for the first via a road station 10 under control, informs the present location of the mobile station to a registration station. The registration station holds the data of the present location, and always updates it in real time. Therefore, the notice of the present location of the mobile station 16 to the registration station is limited only when the ground station 30 detects the mobile station 15 for the first via the road station 10 under control. In such a way, the communication traffic for the notice of the present location can be reduced, and it is possible to prevent the communication traffic for the regular information from being blocked.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a mobile communication system, more specifically, a system for detecting the position of a mobile station in a mobile communication suitable for communication with a vehicle such as a car. Regarding.

(Prior Art) As a conventional mobile communication system to which the present invention is particularly related, there is a car telephone system, for example.As is well known, a conventional car phone system has two base stations covering a predetermined service zone. Some base stations employ a cellular system in which the zones of adjacent base stations partially overlap each other to ensure continuity of communication to mobile units.

When receiving a call to a mobile station, it is necessary to identify the current status of the mobile unit. In conventional cellular car phone systems, each time a mobile station receives a call, a single network makes a simultaneous call to multiple zones, and the current location is determined by detecting the response from the mobile station. , was making an incoming connection.

(Problem to be Solved by the Invention) In the cellular system, different frequencies are used between a plurality of adjacent cells, that is, cells, to avoid radio wave interference. In order to effectively use the limited frequency band,
It is preferable to subdivide the zone configuration and use it once again for the same frequency p, ``<''. This imposes the burden of frequency switching control on both mobile stations. This tendency becomes more pronounced as the moving speed of the moving object increases. In order to solve this problem, in the conventional cellular system, it was necessary to widen each zone or increase the allocated frequencies. However, as is well known, increasing frequency allocation is extremely difficult.

Conventional cellular car phone systems are designed primarily for voice communication, and are therefore not necessarily suitable for services that transmit large amounts of data at high speeds. For example, in land transportation such as automobiles, in order to perform navigation to guide appropriate routes depending on road congestion and weather conditions, and to efficiently manage the operation of a large number of vehicles,
It is necessary to transmit large amounts of data at high speed between in-vehicle devices and ground base stations. Conventional car phone systems are not necessarily suitable for a wide variety of services, including high-speed data communications, because the frequency of transmission signals is limited to the voice band.

In addition, each time a call arrives, each base station makes a simultaneous call, and the mobile station responds before connecting the call, making connection control for incoming calls complicated and requiring a relatively long time to set up the connection. Ta. Furthermore, since the current location of a mobile object cannot be known unless the mobile station 4 receives a call individually, it is not suitable for a user such as a transportation company that owns a large number of vehicles to efficiently manage the operation of those vehicles. There wasn't.

Therefore, multiple base stations that wirelessly link with a mobile station can be connected without intervening radio wave areas between adjacent base stations. If spaced apart in J1, these base stations would be able to use a single frequency for the radio link. In such a mobile communication system, the number of base stations that can communicate with a mobile station changes from 1 to 4 as the mobile station moves. To do this, the system must always know the current location of the mobile station ;d. However, even if the current location of a mobile station is known, it does not guarantee that this will actually be the location number when an incoming call is received.
In the case of a system applied to general roads, the movement of a moving object is two-dimensional, and its movement can be accurately predicted.1. It would be difficult to efficiently control incoming calls, and it is undesirable for traffic to concentrate on communication for determining the location of a mobile station, which would impede communication traffic for the entire system.

In view of such demands for mobile communication, it is an object of the present invention to provide a mobile station position-dependent detection system that enables appropriate communication with mobile stations.

(Means and effects for solving the problems) According to the present invention, a plurality of base stations each perform wireless communication with a mobile station, and a communication line network that accommodates the plurality of base stations and exchanges communications with them. In a mobile station location detection system for mobile communications that includes a plurality of switching centers forming a When a mobile station is detected for the first time in the area by one of the base stations forming the group, the switching center housing the base stations forming the group is , report the detected location of the mobile station to the switching center where the mobile station is registered,
The exchange with which the mobile station is registered records the reported location of the mobile station.

The mobile station's registered switching center maintains the mobile station's current location data and constantly updates it in real time. Since the current location is reported only when the mobile station is detected for the first time in the area, the communication traffic for reporting the current location is small, and the communication traffic of the original information is not obstructed by this.

For example, when communicating with a mobile station, the location stored for the mobile station is obtained at the switching center where the mobile station associated with the communication is registered.

Therefore, a base station near this location communicates with the mobile station. In this way, as long as the target mobile station is active, it is possible to efficiently (terminate) the target mobile station.

The present invention is applied to a new mobile communication network system in which the current location of a mobile station is managed by a registration station.
Detailed explanation of an embodiment of a mobile station position detection system for mobile communications 41
do.

FIG. 2 shows an embodiment in which the mobile communication system to which the present invention is applied is applied to land transportation, particularly road traffic for vehicles including automobiles, as a road-to-vehicle individual communication system. Generally, a plurality of roadside stations 1O are arranged at predetermined intervals, for example, at intervals of several hundred meters to several kilometers, along local roads and expressways. This interval may be set to an appropriate value depending on, for example, the vehicle speed allowed on the road. It is a station.

The road j and three circuits 1O have a transmitter/receiver a14, which transmits and receives radio waves 18 to and from a mobile station mounted on the additional supercar 12, that is, an on-vehicle device 18 (Fig. One of the characteristics of this embodiment is that the size of the zone 20 is much smaller compared to the arrangement interval of the roadside stations 10. are arranged intermittently. Its diameter may be, for example, on the order of several tens of meters to 100 meters. Therefore, between two adjacent zones 20, there is an area where the mobile station 16 does not substantially respond to the radio waves transmitted by the Route E station 10, that is, a "Tsubame radio wave area".
The vehicle 12 is only allowed to use the roadside station while it is included in the zone 20.
Can communicate with O. This communication takes place at high speed.

As will be seen from now on, in this method, the same frequency can be repeatedly and effectively used for the three adjacent roads 10. Therefore, basically, the road station 10 and the mobile station 1
6, it is sufficient to use a single frequency for the entire system. For systems that allow full-duplex communication.

A pair of frequencies that are different from each other are used at the top and bottom.

This eliminates the need for frequency zone switching as in conventional cellular systems. ζ- Because of these characteristics, this method is called the "intermittent minimum zone method", and the zone 20 is called the "minimum zone".

The roadside station IO constitutes a part of the road-to-vehicle individual communication line network 22, and in this embodiment, via the line network 22, a general telephone line network 24, a general packet switching network, etc.
25, a system center 26, and other communication facilities such as a user center 28. In this embodiment, the road-to-vehicle individual communication line network 22 has a station hierarchy configuration as illustrated in FIG. A communications network that performs switching or exchange between networks.

This will be explained in detail later.

In such an intermittent minimum zone method, it is possible to increase the speed of communication between the mobile station IC and the road station IO, and a variety of services including high-speed data communication are provided. For example, navigation that guides participating vehicles 12 such as cars to appropriate routes depending on road congestion and weather conditions;
In order to efficiently manage the transportation of a large number of vehicles 12, the center 2G and 28
Data communication can be performed between the mobile station 16 and the mobile station 16.

Referring to FIG. 3, the road-to-vehicle individual communication line network 22 in this embodiment includes a district station 30 that accommodates a plurality of roadside stations 1O located in a certain area, and a district station 30 that connects a plurality of district stations 30 over a certain area. It has a hierarchical structure consisting of regional stations 32 and a general office 34 that accommodates several of these regional stations 32. These exchanges 3 including the roadside station 10
0.32.34 is called the ground station. In this embodiment, the lines between the district stations 30, the regional stations 32, and the general office 34 form a tree-like line network consisting of trunk lines and trunk lines 36 such as diagonal lines. It constitutes a type line network.

It goes without saying that the present invention is not limited to this alternative form, and may take other forms such as a local hierarchy structure depending on the type of road such as a general road or an expressway, or a linear network. stomach.

A trunk line 38 for the general public telephone network 24 and the data exchange network 25 is accommodated, for example, in the central office 34.

The system center 26 is, for example, an information processing system that processes navigation for the participating vehicle 12. Further, the user center 28 is an information processing system that independently manages the operation of the subscribed vehicles 12 belonging to a specific user. Of course, these are regional stations 32 and district stations 30.
may be connected to.

The general office 34, the regional office a2, and the district office 30 each have a unique office code. Among them, by representing the codes of the general station 34 and the regional station 32 in a station hierarchy structure, the registered ground station code 52 (fourth
) is formed. For a subscriber vehicle 12 of a large user who owns a large number of subscriber vehicles 12, a user code unique to that user may be used instead of the local station code.
The mobile station 1B mounted on the participating vehicle 12 is registered, for example, in a regional station 32, and is given a unique mobile station coat 54 by the local station 32. Therefore, nationwide, the on-vehicle device, ie, the mobile station 18, is identified by the ground station code 52 and the mobile station code 54. In addition, participating vehicles 12
may be registered at the general office 34 or the district office 30.

The identification code for identifying the mobile station 1G, 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 a code that identifies the mobile station 16 registered in the regional station a2, and includes a ground station code 52, a mobile station code 54,
The system code 58, which includes the system code 5B for identifying this system, is a code that specifies this system to distinguish it from other systems, and may be omitted inside this system. Therefore, the static code 58 In addition to functioning as an identification number for each mobile station 16 within this system, it also functions closely with the numbering system used when a call is received from the general telephone line network 24, data exchange network 25, or center 28, 28 to the mobile station 16. There is a relationship.

The mobile station 1B of the joining vehicle 12 has a vehicle code generator 130 (
3), which is the functional unit that generates the vehicle code assigned to the mobile station 16. This vehicle code includes a ground station code 52 that identifies the registration station where the mobile station 16 is originally registered, and a mobile station code 54 of the mobile station 16. These codes are sent to the vehicle code generator 130. The information is set, read out, and transmitted in response to polling from the roadside station 10, which will be described later.

For example, as shown in FIG. 1, it is assumed that a mobile station 1B is registered in one regional station B1 accommodated in a central station A1. Ground station code 52 that identifies the area station 32
is rAIB+J, and if the mobile station code 54 of the mobile station 1B in the area station is rMo3J, the mobile station is identified by the static vehicle code rA+B+Mo3J.

The dynamic code 80 is a code corresponding to the movement state of the participating vehicle 12, and is effectively used to grasp the current situation of the participating vehicle 12 and navigate. Therefore, it is a vehicle-specific code related to the driving area and movement status of the subscriber vehicle 12, and is a code unique to the general telephone line network 24, data exchange network 25,
It plays an important role in searching the vehicle location for individual communication from the center 26, 28, providing route guidance information to the travel destination of the subscriber vehicle 12, etc. Therefore, in this embodiment, the operation of the subscriber vehicle 12 is The driving area code 84, which includes a destination code 62 indicating the destination and a driving area code 64 indicating the current driving area, is transmitted to the general station 34 and the earth station 32.
and the station code of the district station 30. In addition to this,
A link code identifying the established communication link may also be included.

In this embodiment, as shown in FIG.
0 is prepared at the earth station 32. Running vehicle table 8
0 stores data indicating the current driving area of the local station's member vehicles 12 registered as belonging to the earth station 32, by station area, and data indicating the current driving area of the local station's participating vehicles 12 registered as belonging to the earth station 32. Data on participating vehicles 12 is stored for each registration station. These data in the running vehicle table 80 are constantly updated. Similar vehicle tables may be provided at the district office 30 and the general office 34, for example.

In this embodiment, a passing vehicle table 170 is also provided in the memory of the district office 30.
is a table that stores the data of the mobile station 1B detected in the service zone 20 of all road stations accommodated in the district station 30. Only when detected, the mobile station 1 communicates with the registered station to report its current location.
The communication traffic for reporting the current location of B can be reduced, and the process of managing the running location at the registration station is simplified. This passing vehicle table 170 is referred to in order to determine whether the mobile station 18 whose detection has been reported from the roadside station 1O is a station that has newly entered the area under the jurisdiction of the district station 30. In addition, when a relay group configuration of roadside stations 10 is not adopted for incoming calls, it is also used to search for roadside stations 10 that can receive calls to the mobile station 16.

As conceptually shown in FIG.
is arranged, which is a passing vehicle table 82 (FIG. 3).
The zero passing vehicle table 82 includes a storage area in which information to be transmitted and received with the mobile station 18 is stored.
It holds data regarding participating vehicles 12 passing through the minimum zone 20 of . These data are vehicle specific code 50
and 80, and is constantly updated as the joining vehicle 12 passes.

In this embodiment, the mobile station 1B is a member vehicle 12 such as a car.
This is an in-vehicle device that is mounted on a vehicle and transmits and receives data such as navigation information and operation management information, messages, and image signals to and from the roadside station 10, and displays these signals visually and/or audibly to passengers. Preferably, the vehicle is equipped with a video display, a facsimile transmitting/receiving device, a voice synthesizing device, etc., which provide an image and audio interface to the passenger. Furthermore, the mobile station 1B, which may have an automatic operation control function for the control mechanism of the participating vehicle 12, has a random number table function, and according to this function, in response to polling from the road station 10, the mobile station 1B communicates with the road station IO. An available free channel is selected by the road station 10 from among a plurality of channels on the link 18 .

Communication between the mobile station 16 of the subscribing vehicle 12 and the base station 10 is carried out by polling using a frame 100 having a format as illustrated in FIG. is 883 milliseconds (intestinal S),
The transmission rate is 512 Kbit/s, and multiple channels are multiplexed into a number of time slots.

In principle, the required bidirectional communication is completed within this 1 frame period. A single frequency is used for the radio link per day. In the case of full-duplex communication, a pair of different frequencies are used for upper and lower frequencies. However, these frequencies may be fixed, and the same frequencies are used no matter which roadside station 10's zone 20 the subscribing vehicle 12 moves to.

An introduction section 102 is located at the beginning of the frame 100, and includes a preamble, a synchronization signal, a polling identification signal, a road station IO code, and the like.

Using this, the roadside station 10 polls the mobile station 18 within the zone 20 at a predetermined period, as shown in FIG.

The mobile station 1B is in the receiving mode in the idle state, and becomes the transmitting mode when it finishes receiving the introduction section 102.

The introduction section 102 is followed by a vehicle recognition section 104, which includes:
Mobile station 18 responds to polling with vehicle specific code 50.
and 60 are transmitted, and the roadside station 10 recognizes this. Advantageously, by performing two-block repeated transmissions, the recognition rate of participating vehicles 12 is significantly improved. Mobile station 16 selects one of the plurality of channels from the random number table in response to polling. In response to the polling, the vehicle code generator 130 of the mobile station 16 generates the ground station code 52 and mobile station code 54 that are set and registered for the mobile station 18, and uses this channel to generate static It is transmitted to the roadside station IO as a vehicle-specific code 50 or a service function code (see FIG. 6).

For example, in the example shown in FIG. 1, it is assumed that eight street stations 10 are housed in one district station C1 housed in the area tube AOB+, and station codes no. -07 are assigned to each of them. The sixth roadside station 10 from the left in the figure is designated by the station code rAoB+C+DsJ. In this example, the static vehicle code 50 is rAIB+No.
If the mobile station 1B with 3J is now polled while passing within the zone 20 of the roadside station AoB+C+D5, the mobile station 18 will return the identification code rAIB+Mox J as the ground station code 52 and the mobile station code 54.

Returning to FIG. 5, in this embodiment, a relay communication unit 106 is arranged following the vehicle recognition unit 104, and this is used to communicate with the roadside station.
Beacon-type dynamic navigation information such as traffic information and a registration response signal (ACK or NACK) are transmitted from mobile station 0 to mobile station 18 . If the channel selected by the mobile station 16 does not conflict with any other channel, it is registered with the road-L station 10 and an ACK signal is transmitted to the mobile station 16.

This is followed by the vehicle communication section 108, which in this embodiment performs full-duplex communication between the roadside station IO and the mobile station IB. The frequency differs by η under −L, and the channel specified by the road station 10 is used. but,
The same frequency is used even when the subscribing vehicle 12 moves to the zone 20 of the adjacent roadside station 10. Of course, half-duplex or unidirectional communication may be used. In the vehicle communication unit 108, the mobile station 16
Data such as navigation information and operation management information, messages, and image signals are transmitted and received between the system center 26 and the user center 28, and the information is displayed to the passenger of the subscriber vehicle 12 in the form of images and sounds. Also, −
Communication with the general telephone line network 24, data exchange network 25, or other mobile stations 16 within the system is performed in the same manner.

The roadside station 10 may hold data on the participating vehicles 12 obtained from the mobile stations 16 within the zone 20 in the passing vehicle table 82 at each polling cycle.

The roadside station 10 transfers these data to the district station 30 through the line 36. In this embodiment, the district station 30 transmits the data to a specific mobile station, for example, A!
It is configured to report this to the registration authority AIB+ when it detects BIMO3.

As shown in FIG. 8, for example, the mobile station AIBIMO3 continues traveling on the road 138, passes the roadside station AoB+011]7 at the end of the district station AoB+C+, and reaches the first roadside station of the adjacent other district station AOBIC2. Assume that you have entered zone 20 of AOBIC2DO. This street station A6BIC2
The DO reports the vehicle code 50 of the mobile station AIBIMO3 to its −L-ranked district station AoB+C2.
+02 stores this in the passing vehicle table 170. At that time, the same district office As B + C2 stated that this vehicle code rA+B+Mo3J had not been registered in the passing vehicle table 17 until now.
Check whether it is stored in 0 (172.Figure 6)
, if it is determined that it has not been memorized, the L-ranked region tube A
It transfers its current location data to registration station AIB+ via OB+. In this case, the station code rAoB+C:2J up to the district station 30 is sufficient as the current location data.

To explain in more detail, as shown in Figure 3, the district office 30
is equipped with a station code generation section 132 that generates a ground station code 52 that specifies the district station 30.

In the district station AOBI02, rAoB+C:2J is set as the ground station code 52 in the station code generation unit 132. The vehicle code rAIBIM63J of the mobile station 16 received by the roadside station AoB+G2Do is temporarily stored in the passing vehicle table 82 of the roadside station IO, and then sent to the L-ranked district station AO.
Transferred to BI02.

District station AOB l c2 has this vehicle code “4181
When it is determined that MO3J has not been stored in the passing vehicle table 170 (1"r2), as shown in FIG. There is something
1ift ffl and transfers this to the regional station AIB+ by 1". At this time, the district station AOBIC2 transmits its own location information as information indicating the current location of the mobile station 1B. This location information is , its ground station code rAoB+ in the form of driving area code 64 of dynamic vehicle code 80
Contains c2J.

Exchanges above district station AQBI02, such as regional stations ao Bl, and general stations AO and A! is the vehicle code rAIBIMO3 of the mobile station position data to be transferred.
It identifies its destination from J and relays it to its registration station, ie, regional station AI B+ in this example. Upon receiving the mobile station position data, that is, the static vehicle code 50 and the dynamic vehicle code 60, the registration station AI B+ identifies the target mobile station 1θ, based on the mobile station code 54.
That is, in this example, station MO3 is identified and these position data are stored in the corresponding storage location of the traveling vehicle table 80. In this way, the traveling vehicle table 80 of the registration station AIB+ is constantly updated with new data. In this method, communication for reporting the current position occurs only when the mobile station 1B is newly detected within the jurisdiction of the district station 30, so the communication traffic can be reduced, and the processing of running position management at the registration station is is simplified.

The current location data of the mobile station 16 is constantly updated.

Focusing on a specific mobile station, for example MO3K, its position data is transmitted from the district station 30 as described above, for example, when any of the district stations 30 detects the mobile station Ml+3 for the first time via the road station 10 within its jurisdiction. The information is reported to the registration station AIB+, and the stored contents of the mobile station 803 in the traveling vehicle table 80 are updated.

Note that the first time a certain district station 30 detects a specific mobile station 1B is not necessarily through the on-the-road station 10 located at the end of the coverage area of that district station 30; For some reason, I turned off the power to the onboard device 1B of the vehicle 12 and moved it to the area of another district station 30.
When the mobile station 16 is turned on, the mobile station
may also be detected.

centers 2B, 28 and general telephone line network 24. Information addressed to the mobile station 18 from the data exchange network 25 is temporarily stored in the memory 42 of any ground station, for example, the road station 10. The roadside station 10 compares the static vehicle-specific code 50 obtained from the mobile station IB within its jurisdiction with the destination code of the transmission information, and determines whether there is information to be transmitted to the corresponding mobile station 1B. When a match is detected between the two, the memory 42
The information stored in the mobile station 16 is transmitted to the mobile station 16 using the downlink channel of the vehicle communication section 108. Information transmitted from the mobile station 16 via the uplink channel is stored in the memory 42.
is temporarily accumulated. This upstream transmission information is later transferred to the center 26.2 or the general telephone line network 24 via the road-to-vehicle individual communication line network 22.

When the vehicle communication unit 10B completes, it is followed by a communication completion unit 110 that transmits upper and lower response signals. This is a signal confirming the completion of the transmission, but not confirmation of the information content.

In this way, the communication of the l frame 100 takes place while the participating vehicle 12 is traveling within the service zone 20 of the roadside station 10. While the subscribing vehicle 12 is traveling in a radio-free area between two adjacent zones 20, the mobile station 16 cannot communicate with the road-to-vehicle individual communication network 22, using a single frequency. This may make one think of a conventional leaky coaxial cable broadcasting system, but this embodiment is not a broadcasting system, but an individual communication system, and moreover, it is different from a leaky coaxial cable broadcasting system in that there is no radio wave area. It is fundamentally different from that.

In principle, this embodiment is configured such that one communication is completed while the joining vehicle 12 is included in a certain minimal zone 20. Regardless of whether it is a general road or an expressway, as long as the vehicle is driving normally on that road, the vehicle 1 that has joined several minimal zones 20 across the above-mentioned no radio wave area.
Roadside stations 10 are arranged along the road at such intervals that a considerable amount of communication can be carried out by the traveling of the roadside stations 10. In other words, by arranging the roadside stations 10 at such a distance, the mobile station 1 with a large amount of communication traffic can
2, it is possible to sufficiently achieve the required communication.

In this embodiment, in order to efficiently control incoming calls to the mobile station 18, a plurality of roadside stations 1O are arranged in a broadcast group according to the area in which they are located. When a call arrives at the mobile station 16, the group structure is such that the group is used as a unit to perform the relay communication.For example, one district station 30 may be used as a unit, and all the road stations IO accommodated therein may be set as one relay group. Alternatively, out of the street stations 10 housed in the district station 30, a number of regionally grouped stations may be used as a unit to create a circular group. In the latter case, as shown in FIG. 3, the district station 30
A road station table 134 is provided in , which stores which nine road stations 10 within the service area are included in which broadcast group. This table 134 is referred to when a call is connected and a relay message is issued. In this case, as described above, it is preferable that the area managed by the passing vehicle table 170 be the same as this notification group configuration.
It is advantageous that the area managed by 0 is the same as the area of the broadcast group managed by the route 1 station table 134.

In the example of FIG. 8, roadside stations DO"D7, which are regionally grouped around road 138, are accommodated in one district station AOBICI, and these roadside stations form a circular group as one unit. District stations AoB+C ;+ also accommodates a related area, such as the street station O, which is separate from this area.

The mobile station AIBIM is sent from the center 26 or 28 using mobile station location data that is constantly updated at the registered station AIB.
The sequence in which a call arrives at O3 will be schematically explained with reference to FIG. Mobile station AIBIM from center 26 or 28
Messages addressed to O3 have their destination code rAIB+
It is sent via the central office 34 to the registration station AIBI together with a header in the form of a static vehicle-specific code 50 containing the Mo3J. This message transfer is performed by identifying the destination code rAIB+Mo3J of the message at each relay station. Registration Authority AIB.

When receiving this message together with the header, it checks the registration qualification of the mobile station AIBIMO3 to receive the call based on the destination code, and if the qualification is satisfied, stores the message in a memory (not shown) for an hour (140). ), although it is not shown in the figure, at this time the registration authority AIB,
returns a reception confirmation response to the center 26 or 28.

Therefore, the registration station AIB+ refers to the running vehicle table 80 and uses the mobile station position data to identify the destination mobile station AIBIMO.
Check the current position of 3. As a result, the mobile station AIBIMO
3 is found to be, for example, rAoB+c2J, the registration authority AIB+ creates from this a dynamic vehicle-specific code 60 containing the address rAoB+czJ of the district office 30 as the driving area code 64. Registration station A, B
, reads the transmitted message from memory, adds a dynamic code 80 to its header, and transmits it to the district station AOBIC2.

Relay stations such as the central station 34 and the regional stations 32 identify the message's dynamic vehicle-specific code 60 and forward it to the destination station AoB+C2. District station AoB+Cz is
When this message is received, it is relayed to all the over-the-air stations Do etc. accommodated in the local station.

Note that when the roadside station 10 housed in the district station, for example AOBIG2, forms a plurality of circular groups, the district station AOBIC2 uses the static vehicle-specific code 50 received along with the message from the registration station AIBI to With reference to the vehicle table 170, the roadside station 10 indicated by the travel area code 64 of the mobile station AIBIMO3 is identified.

According to this identification result, the district station AoB+Gz refers to the road station table 134, classifies the broadcast group to be accessed by f1, and broadcasts the broadcast to all the road stations 16 forming this broadcast group.

This circular includes a delivery request, a message, and the message's destination code rA+B+Mo3J.
Upon receiving this, 0 stores the message in the -H memory 42 and polls the mobile stations 16 included within its service zone 20. This polling is performed at the introduction section 102 of the frame 100 as described above.

The active mobile station 16 included within the service zone 20 of the roadside station 10 generates vehicle codes 50 and 80 in the vehicle code generator 130 in response to this polling;
This is sent back to the roadside station IO. This is the vehicle recognition unit 104
is used. The roadside station IO temporarily stores the vehicle code returned from the mobile station 1B in the passing vehicle table 82, and compares the static vehicle-specific code 50 with the destination code rA+B+Mo3J of the message (142). When the two match at the station IO, the station IO reads the transmitted message from the memory 42 and sends it to the vehicle communication unit 1.
08 on the channel of the mobile station AIBIMO3. Mobile station AIB+Mox that received the message
returns a reception confirmation response using the communication completion unit 110,
This is finally transferred to the registration station 34 via the ground station. If the reception acknowledgment includes an acknowledgment ACK, the district station AoB+l:+ cancels the delivery request to the other road station 10.

The remaining roadside stations 10 whose vehicle codes do not match in step 142 discard the messages stored in the memory 42 under the control of the district station AoB+C+, and this process ends. It should be noted that each station returns an acknowledgment response at each stage of this mobile station incoming sequence, but this is not shown in FIG. 7 to avoid complication of the diagram.

Note that the mobile station 16 may be configured to receive a call from a specific roadside station 10 selected according to a predetermined procedure without making a call in the mobile station arrival sequence. In that case, the district station, for example, AoBI02, is a registered station The passing vehicle table 170 is referred to based on the static vehicle specific code 50 received with the message from A, B, and the roadside station 10 indicated by the driving area code 84 of the mobile station A+B+Moz is identified. For example, by accessing an adjacent road station related to this identified road station IO in a predetermined relationship, the mobile station AIBIM
Attempt an incoming connection to O3.

To summarize, in this embodiment, each mobile station 18 is registered in advance with a specific ground station. When the district station 30 detects a specific mobile station 16 for the first time via the roadside station IO under its control, it notifies the registration station of its current location. The registration station maintains this current location data and constantly updates it in real time. The current location of the mobile station IB is reported to the registration station only by the district station 30 through the roadside station IO within its jurisdiction.
This is limited to when the current location is detected, so there is not much communication traffic for reporting the current location, and therefore the communication traffic for the original information is not obstructed by this.

When incoming a call to a mobile station 16, access the registration station where the mobile station 18 is registered to find its current location,
Establishing an incoming connection from a roadside station 10 related to or estimated from its current location to a target mobile station 16;
This avoids the problem of positional uncertainty when a call arrives at the mobile station 16, and performs efficient call termination control.

An embodiment in which the present invention is applied to a road-to-vehicle individual communication system has been described. However, the present invention is not limited thereto, and can be effectively applied to individual communication with any moving object other than a vehicle, such as an individual, ie, a pedestrian in a broad sense.

The embodiments described here are for illustrating the present invention, and the present invention is not necessarily limited thereto, and modifications and variations that can be made by those skilled in the art without departing from the spirit of the present invention. Modifications are within the scope of this invention.

(Effects of the Invention) In the mobile communication system according to the present invention, a mobile station is registered with a specific exchange, and the current location of the mobile station is managed by the registration station. When a switching center inspecting a base station detects a specific mobile station for the first time via a base station within its management area, it notifies the registration station of its current location, and the registration station retains this information. Therefore, the communication traffic for reporting the current location does not increase, and the original information communication can be properly ensured.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram conceptually showing a mobile station position detection system for mobile communication according to the present invention. FIG. 2 is a conceptual block diagram showing an embodiment in which the mobile communication system to which the present invention is applied is applied to road traffic for vehicles as a road-to-vehicle individual communication system; FIG. 3 is a conceptual block diagram showing the implementation shown in FIG. FIG. 4 is an explanatory diagram showing an example of the format of a vehicle-specific code in the embodiment. 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, Fig. 7 is a sequence diagram showing an example of an incoming call sequence to a mobile station, and Fig. 8 is a sequence diagram showing an example of a sequence for detecting the position of a mobile station in the same embodiment. FIG. 2 is an explanatory diagram conceptually showing initial detection of a station. Explanation of the symbols of the main parts 10,... Roadside station 12130. Joining vehicle ia, Transmitter/receiver 20, Minimum zone 22, Road-to-vehicle individual communication network 30, 32, 34, Switching station, Ground station 42, Memory 80, Traveling Vehicle table 82.170. , passing vehicle table 130, , , vehicle code generation section 132, , , station code generation section +34. ．． , , On-road station table patent applicant Oki Electric Industry Co., Ltd. Representative Takao Katori Volcano Takao Road car space Ikegobetsu time! Zuki Kaifu, = 1q Middle mortar solid waste cord and former,) Example 4-Fig.

Claims (1)

[Scope of Claims] A plurality of base stations, each of which communicates wirelessly with a mobile station, and a plurality of exchanges forming a communication line network in which the plurality of base stations are accommodated and exchanges communications for the plurality of base stations. A mobile station location detection system for mobile communications including a base station, wherein the mobile station is registered with one of the plurality of switching centers, and regionally related stations among the plurality of base stations form a group. When the mobile station is detected for the first time in the area by any of the base stations forming the group, , notifying a switching center to which the mobile station is registered the location of the detected mobile station, and the switching center to which the mobile station is registered stores the notified location of the mobile station. A mobile station position detection system for mobile communications.