JPH01311632A - Incoming control system for mobile body communication system - Google Patents

Abstract

PURPOSE:To perform communication with a targeted mobile station appropriately by reducing the probability of invalid incoming connection to the mobile station by paying special attention on a base station at the end of exit of each exchange station in its area at the time of recognizing the present location of the mobile station. CONSTITUTION:When a road station (base station) D7 being brought into contact with an adjacent section station A0B1C2 at the end of a section station A0B1C1 detects the mobile station 16, the section station A0B1C1 transmits the data of the mobile station setting a boundary display bit at (1), and a section station A1B1 that is a registration station stores position data in a traveling vehicle table 80. And when the boundary display bit shows (1) at the time of indexing the traveling vehicle table 80 about the mobile station 16 by the registration station A1B1, the station A1B1 holds the transmission of the message until the position data showing (0) by boundary display bit about the mobile station 16 is received afterwards. Thus, by paying the special attention on the station at the exit of the section station 30 in its area, it is possible to reduce the probability of the invalid incoming connection to the mobile station 16.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a mobile communication system, more specifically, a mobile communication system suitable for communication to a vehicle such as a car, in which incoming calls to a mobile body are controlled. Regarding the control method.

(Prior Art) As a conventional mobile communication system to which the present invention is particularly related, there is, for example, a car telephone system.As is well known, a conventional car phone system includes a base station that covers a predetermined service purpose. Some base stations employ a cellular system that is arranged two-dimensionally so that the zones of adjacent base stations partially overlap with each other to ensure continuity of communication to mobile units.

When terminating a call to a mobile station, it is necessary to identify the current location of the mobile body. In conventional cellular car phone systems, each time a mobile station receives a call, the network makes a simultaneous call in multiple zones, and by detecting the response from the mobile station, the current location is determined and one incoming call is connected. I was doing it.

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

Conventional cellular car phone systems are designed primarily for voice communications, so they are not necessarily suitable for services that transmit large amounts of data at high speeds. In order to efficiently manage the operation of a large number of vehicles and navigation systems that guide users to appropriate routes depending on congestion and weather conditions,
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.

Furthermore, each time a call arrives, each base station calls the destination all at once, and after the mobile station responds, the incoming call is connected, making incoming call connection control complicated and requiring a relatively long connection setup time. Ta. Furthermore, since the current location of a mobile object cannot be known unless the mobile station 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. .

Therefore, if multiple base stations that are linked to a mobile station by a focal line are placed apart from each other with a no-radio wave area interposed between adjacent base stations, these base stations can transmit a single radio wave as a radio link. In such a mobile communication system, which may be able to use frequencies of For this purpose, the system must always know the current location of the mobile station. However, even knowing the current location of a mobile station may not guarantee that it will actually be at that location when an incoming call to it occurs, especially for systems applied to public roads. The movement of a mobile object is two-dimensional, and it would be difficult to accurately predict the movement and perform efficient call termination control.

In view of such demands for mobile communications, the present invention is a new mobile communications system that enables high-speed communications without occupying many frequencies, and is capable of efficiently controlling incoming calls to mobile stations. The purpose is to provide an incoming call control method for mobile communication systems.

(Means and Effects for Solving the Problems) According to the present invention, there are a plurality of base stations that each communicate with a mobile station via a wireless link, and a communication line that accommodates the plurality of base stations and exchanges communications with them. In a call termination control method for a mobile communication system that includes multiple exchanges forming a network, adjacent base stations among multiple base stations are placed in an area where mobile stations do not substantially respond to wireless link radio waves. A mobile station is registered with one of a plurality of exchanges, and regionally related base stations among the plurality of base stations form a group and are separated from each other by intervening in one of the plurality of exchanges. When one of the plurality of base stations located in forwarding second location information indicating whether the station is at the outer edge of the area to the registered switching center of the mobile station; the registered switching center of the detected mobile station; When storing the first and second location information and initiating a call to the mobile station, the switching center with which the mobile station is registered refers to the first and second location information stored therein, and If the location information indicates that the mobile station is not at the edge of the area, an incoming connection is made to the mobile station based on the first location information.

For example, when communicating with a certain mobile station, the base station in which the mobile station related to the communication is registered obtains the position from the first position information stored for the mobile station. Therefore, if the second location information indicates that the mobile station is not at the edge of the area, the mobile station communicates with the mobile station based on the location of the mobile station indicated by the first location information. In this way, as long as the target mobile station is active, calls can be efficiently received.

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. An example of the method will be described in detail.

FIG. 2 shows an example 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. A plurality of roadside stations 10 are usually arranged at predetermined intervals, for example, at intervals of several hundred meters to several kilometers, along general roads and expressways. This interval may be set to an appropriate value depending on, for example, the vehicle speed allowed on the road. The roadside station 10 is a ground station that functions as a base station that communicates wirelessly with the subscriber vehicle 12 on the road. .

The roadside station IO has a transceiver 14, which is connected to the participating vehicle 1.
The mobile station installed in 2, that is, the in-vehicle device IEI (Figure 3)
0 transmits and receives radio waves 18 to and from the vehicle 12, and communicates with vehicles 12 existing within the service area, that is, the zone 20.
One of the characteristics of this embodiment is that the size of the zone 20 is much smaller than the interval at which the roadside stations 10 are arranged, and the roadside stations 10 are arranged intermittently. The 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 1B does not substantially respond to the radio waves transmitted by the roadside station 1O, that is, a "no radio wave" zone. zone 20, and the vehicle 12 is within the road station 10 only while it is included in the zone 20.
You can communicate with. This communication takes place at high speed.

As we will see, in this method, adjacent on-the-road stations 1
The same frequency can be effectively used repeatedly for 0 as well. Therefore, basically, the road station 10 and the mobile station 16
It is sufficient to use a single frequency for the entire system for the radio link between In the case of a system that enables full-duplex communication, a pair of different frequencies are used for upper and lower frequencies.

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

The road station 10 constitutes a part of a road-vehicle individual communication line network 22, and in this embodiment, a general telephone line network 24, a data exchange network 25 such as a general packet switching network, and a system center 26 are connected via the line network 22. 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.
and a communication line network that performs switching or exchange between the center 26, 28 and the mobile station 16. This will be explained in detail later.

With such an intermittent minimum zone method, it is possible to increase the speed of communication between the mobile station 16 and the road station 10, and a variety of services including high-speed data communication can be provided. For example, the road-to-vehicle individual communication network 22 is used for navigation purposes that guide member vehicles 12 such as cars to appropriate routes depending on road congestion and weather conditions, and for the purpose of efficiently managing the operation of a large number of vehicles 12. Data communication can be performed between the centers 26 and 28 and the mobile station 1B via the mobile station 1B.

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 earth stations 32 and a general office 34 that houses several of these earth 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 earth stations 32, and the general station 34 form a tree-like line network consisting of trunk lines and trunk lines 3B such as diagonal lines. It constitutes a type line network.

It goes without saying that the present invention is not limited to this network configuration, and may take other configurations such as a local hierarchy structure depending on the road configuration 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 2 is an information processing system that independently manages the operation of the subscribed vehicles 12 belonging to a specific user, and is housed in the general office 34 via a relay line 40. Of course, these are earth station 32 and district station 30.
may be connected to.

The central station 34, the earth station 32, and the district stations 30 each have a unique station code. 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 16 mounted on the participating vehicle 12 is registered with, for example, an earth station 32, and is assigned a unique mobile station code 54 at the earth station 32. Therefore, nationwide, the on-vehicle device or mobile station 16 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 16, that is, the vehicle-specific code, is composed of a static code 50 and a dynamic code 6o in this embodiment, as shown in FIG. The static code 50 is a code that identifies the mobile station 16 registered with the earth station 32, and includes a ground station code 52, a mobile station code 54,
The system code 56, which includes a system code 58 for identifying this system, is a code that specifies this system to distinguish it from other systems, and may be omitted inside this system. In addition to functioning as an identification number for each mobile station 1B within this system, it also functions closely with the numbering system used when calls are received from the general telephone line network 24, data switching network 25, or center 26.28 to the mobile station 1B. There is a relationship.

The mobile station 16 of the participating vehicle 12 has a vehicle code generator 130 (
3), which is a machine section that generates a 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 18. 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 16 in one regional area Bl accommodated in the central office AI is registered. Ground station code 52 that identifies the area 32
is rA+Bth, and if the mobile station code 54 of mobile station 1B in that area is rhos J, the mobile station is identified by the static vehicle code ``^IBINO3J.''

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,
The center 2B plays an important role in searching the vehicle location for individual communication from the 2nd day, providing route guidance information to the travel destination of the subscriber vehicle 12, etc. Therefore, in this embodiment, the center 2B The driving area code 64, which includes a destination code 82 indicating the driving destination and a driving area code 64 indicating the current driving area, is provided by the general office 34 and the regional department 32.
and the station code of district station 30 and the boundary display pin) t3
4a. In addition, the 0 station code may include a link code specifying the set communication link, and the 0 station code may include an on-road station code.The boundary display bit 84a is
As will be described in detail later, this bit indicates whether or not the roadside station lO that detected the mobile station 16 is the roadside station at the end of the area covered by the district station 30.

In this embodiment, as shown in FIG.
0 is prepared in the region section 32. Running vehicle table 8
0 stores data indicating the current driving areas of the own station's member vehicles 12 registered as belonging to the regional division 32, by station area, and data indicating the current driving areas of the own station's participating vehicles 12 registered as belonging to the local area unit 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.

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 16 is stored.
It holds data regarding participating vehicles 12 passing through the minimum zone 20 of . These data are vehicle specific code 50
and 60, and is constantly updated as the participating vehicle 12 passes.

In this embodiment, the mobile station 16 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. The mobile station 16 may also have an automatic operation control function for the control mechanism of the participating vehicle 12. An available free channel among the plurality of channels on the link 18 is selected by the road station IO.

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 bits/second, 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 wireless link 18. 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 zone 20 of the roadside station 10 the subscriber 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 code for the road station 10, and the like.

Using this, the on-road station IO can be set up as shown in FIG.

The mobile station 16, which polls the mobile station 16 in the zone 20 at a predetermined period, is in a receiving mode in an idle state, and becomes a transmitting mode when it finishes receiving the introduction part 102.

The introduction section 102 is followed by a vehicle recognition section 104, which includes:
Mobile station IB 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 18 selects one of the plurality of channels from a random number table in response to polling. In response to the polling, the vehicle code generator 130 of the mobile station 18 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 Figure 1, one district station AoB+ accommodated in the regional station AOB+ (8 street stations 10
It is assumed that the station code Do"Dy is assigned to each of them. The sixth roadside station 10 from the left in the figure is designated by the station code r AOBICI D5J. In this example, the static vehicle rAI as code 50
Mobile station 16 with B+Mo3J is road station Ao B+
When polled from now on while passing through zone 20 of CIUs, mobile station 18 returns identification code rAIBIMO3J as ground station code 52 and mobile station code 54.

Returning to FIG. 5, in this embodiment, a relay communication unit 10B 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 16 . If the channel selected by the mobile station 16 does not conflict with any other channel, it is registered with the road station 10 and an ACK signal is transmitted to the mobile station 16.

This is followed by the vehicle communication section 108, which performs full-duplex communication between the roadside station 10 and the mobile station 16 in this embodiment. The frequencies are different for the upper and lower channels, and the channel designated by the road station 10 is used. However, even if the subscribing vehicle 12 moves to the zone 20 of the adjacent roadside station 10, the same frequency is used. Of course, half-duplex or unidirectional communication may be used, and the vehicle communication unit 108 exchanges data such as navigation information and operation management information, messages, and image signals between the mobile station 16 and the system center 26 or user center 28. is transmitted and received, and the information is displayed to the passenger of the participating vehicle 12 in the form of images and sounds. Furthermore, communication with the general telephone line network 24, data exchange network 25, or other mobile stations 1B in this system is performed in the same manner.

The on-road station 10 may store data on the joining vehicle 12 obtained from the mobile station 1B in the zone 20 in the passing vehicle table 82 at each polling cycle.

The roadside station 10 transfers these f~-ri to the district station 30, the regional station 32, or the general station 34 through the line 36. These stations store the data thus sent in, for example, a running vehicle table 80. In this way, for example, the running vehicle table 80 of the regional station 32 is constantly updated with new data.To explain in more detail, as shown in FIG. The station code generator 132 is provided with a station code generating section 132 that generates a station code of 52.

For example, in the district station AQBICI of FIG. 1, rAoB+(+J is set as the ground station code 52 in the station code generation unit 132. (7) Once stored in the passing vehicle table 82,
It is transferred to the upper district station AoB+G+. As shown in Figure 6, the district office AoB+C+ uses this vehicle code rA+B.
+Mo3J identifies that the registered station is regional station AIB+ belonging to general station A1, and the vehicle code rAIBIM
Transfer BJ to regional station AIB+. At this time, the district station AOBICI transmits its own location information as information indicating the current location of the mobile station 1B. This location information is provided in the form of driving area need 64 of dynamic vehicle code 60 with its ground station code rAoB+c+J and boundary indication bit 6.
4a.

Boundary display (beep) e4a is a bit that indicates whether the road station 10 that detected the mobile station 16 is a station at the end of the area covered by the district station 30. For example, as shown in the 8th cause, on one road 136 such as an expressway, the district office AoB+C
The roadside stations DO"D7 belonging to + are arranged linearly, and the adjacent district station Ao B+ 0 is on the edge of the area under the jurisdiction of the same district station.
When the road station D7 adjacent to the mobile station D7 detects the mobile station 16,
The district station AOBICI displays a significant bit, for example "1", in the boundary display bit θ4a. For this purpose,
The district station 30 is equipped with a street station table 134 (FIG. 3),
In addition, any road station 10 within the jurisdiction is connected to the adjacent district station 30.
In other words, the "edge station" of your own management area.
In this example, the road station AoB+(
+Dy is stored in the road station table 134 of the district station AoB+C+ as the "outgoing end station" in the traveling direction of the vehicle 12. In this example, there is only one station at the outgoing end, but in the case of a general road, the number of stations is generally not limited to one because it is developed two-dimensionally.

Therefore, as shown in FIG. 9, district station Ao B+ (+ means, for example, road station Ao B+
When IMO3 is detected (150), the road station table 13
4 and learns that +Ds is not the outgoing end station of that road station AoB+ (151). Then the boundary display beep)
64a remains "O" (152) and transmits the driving area code 84 and dynamic vehicle specific code 50 to the local station AOB+ (154). station table 1
34, it learns that the on-road station AoBl (+07) is the outgoing end station, so it sets the boundary indication bit 84a to "1" (153) and transmits the mobile station data 50 and 60 (154).

The exchanges located above the district station AgB+ (+, such as the regional station AOB+, and the general offices aO and AI, use the vehicle code rA4B+Mo3J of the mobile station location data to be transferred.
It identifies its destination and relays it to its registration station, in this example regional station AIB+. Registration Authority AI
B is the mobile station location data, i.e. static vehicle code 5
0 and the dynamic vehicle code 60, the target mobile station 1B, that is, the station MID in this example, is identified from the mobile station code 54, and the moving vehicle table 80
These position data are stored in storage locations corresponding to those of the . Of course, these position data are marked with boundary display pins)
64a is also included.

The current location data of the mobile station 1B is constantly updated.

Focusing on a specific mobile station, for example NO3, its location data is transmitted to the district station 30 as described above each time any roadside station 1o detects the mobile station MO3.
is reported to the registration authority AIB, and the running vehicle table 80
The stored contents for mobile station No. 3 are updated. Or, when any of the district stations 3o detects the mobile station MO3 for the first time via the road station 1O within its jurisdiction, the registered station AI
It may be configured to report this to B+.

Information addressed to the mobile station 1θ from the center 26, 28, the general telephone line network 24, and the data exchange network 25 is temporarily stored in the memory 42 of one of the ground stations, for example, the roadside station 10. The road station IO compares the static vehicle-specific code 50 obtained from the mobile station 1B within its jurisdiction with the destination code of the transmission information, and determines whether there is any information to be transmitted to the mobile station 1B that it serves. When a match is detected, the memory 42
The information stored in the mobile station 1B is transmitted to the mobile station 1B using the downlink channel of the vehicle communication unit 108. The information transmitted from the mobile station 1B through the uplink channel is stored in the memory 42.
is temporarily accumulated. This upstream transmission information is later transferred to the center 26, 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 completes the communication, the communication completion unit 110 sends an upper and lower response signal to the vehicle communication unit 108. This signal confirms the completion of the transmission, and does not confirm the content of the information.

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 the radio-free area between two adjacent zones 20, the mobile station 1B cannot communicate with the road-to-vehicle individual communication network 22 and uses a single frequency. One might think of the traditional leaky coaxial cable broadcasting system. However, this embodiment is not a broadcasting system but an individual communication system, and is fundamentally different from a leaky coaxial cable broadcasting system in that there is no radio wave area.

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 traveling of the roadside stations 10. In other words, due to such a remote arrangement of the roadside stations 1O, the mobile station 1 with a large amount of communication traffic
2, it is possible to sufficiently achieve the required communication.

By the way, the sequence in which a call arrives from the center 2B or 28 to the mobile station AIBIMO3 using the mobile station position data constantly updated at the registered station AIB+ will be schematically explained with reference to FIG. Messages addressed to the mobile station AIBIMO3 from the center 28 or 28 are sent via the central station 34 to the registration station AI with a header in the form of a static vehicle-specific code 50 containing its destination code rAIB+Mo3J.
Sent to B+. This message transfer is performed by identifying the destination code rA+B+Mo3J of the message at each relay station. When registration station A+B receives this message along with the header, it checks the registration qualification of the mobile station AIBIMO3 to receive the call based on its destination code, and if it satisfies this, it stores the message in memory (not shown). Although not shown in the figure, at this time, the registration station AlB1 returns a reception confirmation response to the center 2B or 28 (140).

Therefore, the registration authority AI Bl refers to the traveling vehicle table 80 and sends a message 180. (Fig. 1θ), the current position of the receiving mobile station AIBIMO3 is checked from the mobile station position data. As a result, if the significant bit "1" is not displayed in the boundary display bit 84a of the mobile station AIBIMO3 (181), from its current position, for example rAoB+c+J, to the registered station A,
B creates a dynamic vehicle-specific code 60 that includes the address rAoB+c+J of the district station 30 as the driving area code 64 (1B2). The registration station AI 81 reads the transmitted message from memory and inserts the dynamic code 60 into its header. and send it to the district station AoBIC1 (18
3).

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 A, B, at. District station AOBt C
When + receives this message along with the header, it broadcasts the message to all the road stations 10 accommodated therein. This circular includes a delivery request, a message, and the message's destination code rAIBIMO3J. Upon receiving this, each roadside station 10 temporarily stores the message in its memory 42 and includes it within its service zone 20. Poll mobile station 1B. 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 60 in the vehicle code generator 130 in response to this polling;
This is sent back to the roadside station 10. This is the vehicle recognition unit 104
is used. The roadside station 10 temporarily stores the vehicle code returned from the mobile station 16 in the passing vehicle table 82, and compares the static vehicle-specific code 50 with the destination code rAIBIMox J of the message (142). When the two match at the station 10, the station 10 reads the transmitted message from the memory 42 and uses the vehicle communication section 108 to transmit it on the channel of the mobile station AIBIMO3. Mobile station AIBIMO that received the message
3 uses the communication completion unit 110 to return a reception confirmation response, which is ultimately transferred to the registration station 34 via the ground station. If the reception acknowledgment includes an acknowledgment ACK, the district station Ao B+ C+ 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 AOBICI, and the 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.

Returning to FIG. 10, registration station AIBI is connected to mobile station AIBIM.
When the traveling vehicle table 80 is indexed for O3, if the boundary display pin 84a is "1" in step 161, in this embodiment, for example, the mobile station AIBIM
The transmission of the message is deferred (184) until it receives position data indicating that the boundary indicator bit 84a is '0' for O3, which in this case attempts an incoming connection to its mobile station AIBIMO3 via the district station AoB+C+. In this embodiment, by paying special attention to the outgoing end station within the service area of the district station 30, invalid incoming calls to the mobile station 18 can be detected. The probability of connection is reduced.

Note that during the waiting period in step 184, time-limited monitoring may be performed to see if new position data arrives within a predetermined period. Broadcast communication is performed from the local station, ie, AOBICI, to the mobile station AIBIMO3.

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.

Note that the embodiments described here are for explaining 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) The mobile station position detection system for mobile communication according to the present invention has the following features:
In this type of intermittent minimum zone method, when recognizing the current location of a mobile station, the probability of an invalid incoming connection to the mobile station is reduced by paying particular attention to the base station at the outgoing end within the service area of each exchange. It is decreasing. This also ensures proper communication with the intended mobile station as long as it is active. A variety of services including high-speed communication can be provided without occupying a large number of frequencies.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram conceptually showing a mobile communication system according to the present invention, and FIG. 2 is a conceptual diagram showing an embodiment in which the mobile communication system according to the present invention is applied to road traffic for vehicles as a road-to-vehicle individual communication system. 3 is a relay system showing an example of the station hierarchy configuration of the road-to-vehicle individual communication network in the embodiment shown in FIG. 2. FIG. 4 is an example of the format of the 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. 8 is an explanatory diagram conceptually showing the detection of the outgoing road station in the same embodiment. FIG. Fig. 1θ is a flow diagram showing an example of the flow of reporting the location of the mobile station to the registration station, and Fig. 1θ is a flow diagram showing an example of the flow of creating a message address when making an incoming call connection to the mobile station at the registration station of the same embodiment. . Explanation of codes for essential parts io Road station 12, Joining vehicle 14, Transmitter/receiver 20, Minimum zone 22, Road-to-vehicle individual communication network 30.32,
34, switching center, ground station 42, . . . memory f34. , , Driving area code 134a, , , Boundary display bit 80, , Traveling vehicle table 82, , Passing vehicle table 130, , , Vehicle code generation section 132, , , Station code generation section 134. ．． ．． ．． ．． On-road station table patent applicant: Oki Electric Industry Co., Ltd. Agent Number: Takao Volcano Takao's drawing of A (no change in content) Solid state (formerly reached and refrigerated) Fig. 3 Middle white square code Example 4 Rule q +02 104 106 108
110 Fushi - Muftmanototsu, 廿jJ Figure 5 Example of mobile station location reporting flow Figure 9 Example of mobile station incoming call flow Procedure amendment (method) 7 % formula % Mobile communication system incoming call control method 3, amendment Relationship with the case of a person who does
029) Oki Electric Industry Co., Ltd. 4, Agent address: 105 ・ 3rd floor, Moriyama Building, 2-4-1 Nishi-Shinbashi, Minato-ku, Tokyo August 3, 1988 (Delivery date: August 30, 1988)
6. ``Drawings'' to be amended 1. Contents of the amendment The drawing submitted at the time of filing (Figure 3) will be replaced with the official drawing (no changes to the engraving content) as shown in the attached sheet. , list of attached documents

Claims (1)

[Claims] A plurality of base stations each communicating with a mobile station via a wireless link, and a plurality of base stations forming a communication line network accommodating the plurality of base stations and exchanging communications for the plurality of base stations. In a call termination control method for a mobile communication system including a switching center, adjacent base stations among the plurality of base stations are arranged such that an area in which the mobile station does not substantially respond to the radio waves of the wireless link is inserted between them. The mobile station is located at a distance from one another, 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 to be connected to one of the plurality of switching centers. and when any of the plurality of base stations detects the mobile station,
The switching center that houses the base station that detected the mobile station is
forwarding first location information indicating the location of the mobile station and second location information indicating whether the mobile station is at the outer edge of the area to an exchange with which the mobile station is registered; , The switching center where the detected mobile station is registered stores the first and second location information, and when the mobile station receives the call, the switching center where the mobile station is registered stores the first and second location information. , and if the second location information indicates that the mobile station is not at the outer edge of the area, the mobile station is located on the basis of the first location information; An incoming call control method for a mobile communication system characterized by making an incoming call connection to a mobile station.