JP2536429B2 - Mobile communication system - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention is used for mobile radio communication. In particular, a plurality of MCA systems (multi-channel access systems) are provided separately, and a centralized control station is connected by a wired line to build a communication system that enables communication between terminals existing in different MCA systems. , Then all Ms involved in the relevant communication for any call
The CA system relates to a system for controlling the connection and release of a wired line and a wireless line, and the centralized control station controls the connection of a wired line.

[0002]

2. Description of the Related Art Conventionally, mobile communication systems are often MCA systems, each of which is an isolated operation mode, and different M
Technical development of an inter-zone communication system capable of communicating between terminals existing in a CA system is in progress. Also, M
In a communication system other than the CA system, for example, a cellular car telephone system and a mobile telephone system, a dedicated control line or control channel is provided on the network side for call connection and release. Therefore, even in the configuration in which a plurality of MCA systems are connected by a wired line centering on the centralized control station, a method similar to the above-mentioned cell type car telephone system and mobile telephone system is adopted, and call connection release control is exclusively performed. It is also possible to realize it by providing a control line or a control channel (JP-A-56-98953).

[0003]

However, in such a conventional mobile communication system, a method of using a dedicated control line or control channel is conceivable for controlling the connection release of a call across a plurality of MCA systems. ing. However, in this method, at the relay station related to the corresponding call,
The control line or control channel is released only after receiving the control information sent from the centralized control station. Therefore, when a failure occurs in the wired line or the centralized station, the relay station cannot normally receive the control information for releasing the connection, which complicates the release of the wired line and the wireless line. Further, due to the increase in the number of MCA systems added to the inter-zone connection and the inter-zone communication traffic, the above-mentioned non-reception of the control signal and the time delay in releasing the wired line and the wireless line are likely to occur, and the wired line and the wireless line are wasted. There was a problem to hold.

Further, in this method, a dedicated wired line is provided or a separate control channel is provided on a given wired line. To cope with the above-mentioned failure, the equipment of the relay station and the central control station and There have been problems that a redundant configuration is required for the control line or the control channel and that the capacity of the control line or the control channel needs to be increased in order to cope with the increase in traffic.

The present invention solves the above problems,
Even if a failure occurs in the wired line or the central control station, the relay station can release the wired line and wireless line autonomously, the connection can be released quickly without time delay, and it is economical and the communication line usage efficiency is high. It is an object of the present invention to provide a mobile communication system capable of improving the above.

[0006]

According to the present invention, there are provided a plurality of relay stations to which a plurality of shared communication channels are assigned, and a mobile device connected to the plurality of relay stations via wireless lines of the communication channels. In a mobile communication system including a central control station connected to the plurality of relay stations via a wired line in which signals of the communication channel are time-division multiplexed, each time the mobile device transmits after completing the connection. The relay station includes means for adding communication information and communication status information indicating the presence or absence of the communication information to the slot, the relay station includes means for notifying the central control station of the communication status information, and the central control station is the relay station. Means for reporting communication status information from the central control station to the relay station involved in the connection of the call, and the relay station based on the communication status information from the central control station and the presence / absence status of reception from the mobile station. Characterized in that it comprises a means for releasing a wired line and a radio line which are involved in autonomous of the call connection when it detects a free state for a predetermined time continues to communicate come.

Further, according to the present invention, when the central control station continuously detects a communication non-status for a predetermined time based on the communication status information from the relay station, the central control station autonomously participates in the wired connection for connection of the call. Means may be included for releasing the line.

Further, in the present invention, the communication information may be voice or data.

Further, in the present invention, it is desirable that the prescribed time is longer than the prescribed time.

[0010]

After the connection is completed, the mobile station adds communication status information indicating the presence or absence of communication to each time slot and transmits it, and the relay station notifies the centralized control station of this communication status information. The communication status information is reported to all relay stations involved in the connection of the call. When the relay station detects a communication non-status continuously for a predetermined time based on the communication status information from the centralized control station and the presence / absence of reception from the mobile station, it automatically connects to the wired line and the line related to the connection of the call. The wireless line is released, and when the centralized control station continuously detects a non-communication state for a prescribed time based on the communication state information from the relay station, it releases the wired line related to the connection of the call. This allows the relay station to autonomously release the wired line and the wireless line even when a failure occurs in the wired line or the central control station, and can promptly release the connection without time delay, and it is economical and communication line. Can improve the usage efficiency of.

[0011]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a mobile communication system according to an embodiment of the present invention. FIG. 2 is a diagram showing a configuration of communication channels on a wired line of the mobile communication system of the present invention.
In FIGS. 1 and 2, a plurality of relay stations RS _{1 to} RS _{3 to} which a plurality of shared communication channels are assigned, and a mobile station connected to the plurality of relay stations RS _{1 to} RS ₃ via wireless channels of this communication channel. a machine ML ₁ ~ML _3, the centralized control station connected to a plurality of relay stations RS ₁ to RS ₃ signals via a wired line I ₁ ~I ₃ which are time division multiplexed communication channel C
S and.

A feature of the present invention is that the mobile unit ML includes means for adding communication information TIF and communication state information TST indicating the presence or absence of this communication information to each time slot to be transmitted after the connection is completed. The relay station RS includes means for notifying the central control station CS of the communication status information TST, and the central control station CS means for reporting the communication status information TST from the relay station RS to the relay station RS involved in the connection of the call. In the case where the relay station RS detects the communication non-status for a predetermined time continuously based on the communication status information from the centralized control station CS and the reception status from the mobile station ML, the relay station RS autonomously detects the call. It is to include means for releasing the wired line I and the wireless line related to the connection.

Further, when the central control station CS detects a communication non-state for a prescribed time continuously based on the communication state information from the relay station RS, it autonomously releases the wired line I involved in the connection of the call. Including means to do. Furthermore, communication information TIF
Consists of voice or data. Further, the prescribed time is longer than the prescribed time.

The operation of the mobile communication system having such a configuration will be described.

FIG. 3 is a sequence diagram of call connection when a mobile station of the mobile communication system of the present invention calls another mobile station. FIG. 4 is a flowchart showing the connection release of the relay station of the mobile communication system of the present invention. FIG. 5 is a flowchart showing the connection release operation of the centralized control station of the mobile communication system of the present invention. Figure 1 shows multiple MCs centered on a central control station.
1 shows an example of the configuration of a communication system in which the A system is connected by a wired line and communication between terminals existing in different MCA systems is possible. In this example, the central control station CS enables interconnection between the three MCA systems. The service areas of the relay stations RS ₁ , RS ₂ , RS ₃ of each MCA system are SA ₁ , SA ₂ , SA ₃ , and the wired lines I ₁ , I ₂ ,
I ₃ (including a micro circuit) connects the centralized control station CS and the relay stations RS ₁ , RS ₂ , RS ₃ and transfers communication channel information and control channels. Mobile devices ML ₁ and ML
_{2 and} ML ₃ are service areas SA ₁ , SA ₂ and S, respectively.
It is located in A ₃ and can be called with the same call identification code GID.

In FIGS. 1 and 2, the communication channels are time-division multiplexed, and the communication of data corresponding to one call appears at regular time intervals. The time slot is composed of communication information TIF consisting of voice or data and communication state information TST indicating the presence or absence of the voice or data. When the relay station RS receives from the mobile station ML, the communication state information TST is transmitted. When it is in the "on" state and there is no reception, it is sent to the central control station CS as the "off" state. Also,
The relay station RS looks at the communication channel received from the central control station CS and determines whether or not it should be transmitted to the corresponding mobile station ML in the target communication, and if the communication state information TST is in the "on" state, it is received from the central control station CS. The signal (voice or data) corresponding to the communication information TIF is transmitted to the mobile device ML.

The centralized control station CS looks at the communication channel received from the relay station RS, and the communication information T about the target communication.
The IF and the communication status information TST are sent to the corresponding relay station RS, and the communication status information TST received from all the relay stations RS is monitored to determine whether the communication is continued or stopped.

FIG. 3 shows an outline of call connection when the mobile station ML ₁ calls the mobile stations ML ₂ and ML ₃ . The mobile device ML ₁ sends to the relay station RS ₁ a connection request signal CR including the system identification information SID identifying the MCA system to be called and the call identification code GID. When the relay station RS ₁ determines that the request can be accepted, the system identification information SI
Connection request signal CR ′ including D and call identification code GID
To the central control station CS. When the central control station CS determines that the corresponding request can be accepted, it sends the call signal PG including the call identification code GID to the relay stations RS ₂ and RS ₃ . When the relay stations RS ₂ and RS ₃ determine that the corresponding request can be accepted, the call signal P is sent to the mobile device ML ₂ or the mobile device ML ₃ .
Send G '.

When the mobile stations ML ₂ and ML ₃ judge that they can respond, the incoming call response PAC is returned to the relay stations RS ₂ and RS ₃ . The relay stations RS ₂ and RS ₃ return the incoming call response signal PAC ′ to the centralized control station CS. Central control station C
S is a connection start signal CO to the relay stations RS ₁ , RS ₂ and RS _3.
While sending N, the communication channel is secured on the wired lines I ₁ , I ₂ , and I ₃ , and the non-communication time monitoring timer is enabled. The relay stations RS ₁ , RS ₂ and RS ₃ send a channel designation signal CAS to the mobile stations ML ₁ , ML ₂ and ML ₃ . In the relay stations RS ₁ , RS ₂ , RS ₃ , the mobile stations ML ₁ , ML ₂ , M are received at the stage of receiving the connection start signal CON.
Secure a wireless line with L ₃ (assign frequency and time slot), start reception monitoring on the same line, and activate idle time monitoring timers for mobile units ML ₁ , ML ₂ and ML ₃ . .

The mobile stations ML ₁ , ML ₂ and ML ₃ are in a call-enabled state after receiving the channel designation signal CAS, transmit with permission of transmission from the opposite relay stations, and are in the receive state at other times. Become.

1 and 4, the relay station RS cannot receive a signal from the mobile station ML continuously for 3 seconds or more by the no-communication time monitoring timer, or communication state information TST received from the central control station CS. Is in the "off" state, and if it is in the "off" state, one time slot of the communication channel is released in the wired line I for the call, and the assigned frequency and time slot are set in the wireless line. Release the combination of. In addition, the central control station CS
Then, the communication state information TST received from all the relay stations RS related to the connection of the call is monitored, and when the communication state information TST from all the relay stations RS is in the “off” state, the no-communication time monitoring timer is set. It is activated, and after 4 seconds, one time slot of the communication channel is released for the call.

[0023]

As described above, according to the present invention, when a failure occurs in the wired line or the central control station, the relay station can autonomously release the connection. In addition, since there is no control signal reception due to an increase in the number of MXCA systems or inter-zone communication traffic in zone-to-zone connections, and there is no time delay in releasing wired and wireless lines, it is possible to quickly release wired and wireless lines. It has the excellent effect of increasing the efficiency of line usage.

Furthermore, it is not necessary to separately provide a control channel on a dedicated wired line or a given wired line, and equipment for a relay station and a centralized control station for coping with a failure and a redundant configuration of the control line or control channel. Is unnecessary, and measures such as expanding the capacity of the control line or control channel against the increase in traffic are not required.
There is an advantage that an inter-zone communication system including a plurality of MCA systems centering on a centralized control station can be configured with high reliability and economically.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a mobile communication system according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of communication channels on a wired line of the mobile communication system of the present invention.

FIG. 3 is a sequence diagram of call connection when a mobile station of the mobile communication system of the present invention calls another mobile station.

FIG. 4 is a flowchart showing a connection release operation of a relay station of the mobile communication system of the present invention.

FIG. 5 is a flowchart showing a connection release operation of the centralized control station of the mobile communication system of the present invention.

[Explanation of symbols]

CAS channel designation signal (wireless section signal) CON connection start signal (wired section signal) CR connection request signal (wireless section signal) CR 'connection request signal (wired section signal) CS Central control station I ₁ , I ₂ , I ₃ Wired Line ML ₁ , ML ₂ , ML ₃ Mobile device PAC Incoming call response (wireless section signal) PAC 'Incoming response (wired section signal) PG Ringing signal (wireless section signal) PG' Ringing signal (wired section signal) RS ₁ , RS ₂ , RS ₃ relay station SA ₁ , SA ₂ , SA ₃ service area TIF communication information TST communication status information

Claims (4)

(57) [Claims] 1. A plurality of relay stations to which a plurality of shared communication channels are assigned, a mobile device connected to the plurality of relay stations via a wireless line of the communication channel, and signals of the communication channel are time-divisional. In a mobile communication system including a centralized control station connected to the plurality of relay stations via a multiplexed wired line, the mobile device transmits communication information and communication information in each time slot to be transmitted after the connection is completed. The relay station includes means for notifying the central control station of the communication state information, and the central control station receives the communication state information from the relay station for the call. Of the connection to the relay station, the relay station continuously for a predetermined time based on the communication status information from the central control station and the presence or absence of reception from the mobile device. Mobile communication system, characterized in that it comprises a means for releasing a wired line and a radio line which are involved in autonomous of the call connection when it detects a free state of the signal. 2. The centralized control station autonomously releases the wired line related to the connection of the call when detecting the communication non-state for a prescribed time continuously based on the communication state information from the relay station. The mobile communication system according to claim 1, further comprising means. 3. The mobile communication system according to claim 1, wherein the communication information includes voice or data. 4. The mobile communication system according to claim 1, wherein the specified time is longer than the predetermined time.