JP7359681B2 - Line control device and wireless communication system - Google Patents

Description

The present invention relates to a line control device and a wireless communication system, and more particularly to a line control device and a wireless communication system that can ensure communication between a command center and a mobile station during degraded operation due to a failure.

[Description of prior art]
Commercial radio systems (hereinafter referred to as "wireless communication systems") are used in a wide range of industries, from public services to private services, such as transportation, police, fire departments, disaster prevention administration, and railways. It is mainly used for wireless voice and data communications. Wireless systems can be roughly divided into analog and digital systems, but the transition to digital systems, which have excellent frequency efficiency and facilitate data transmission, is progressing.

Furthermore, with the spread of mobile phones, smartphones, and IP wireless, it has become possible to construct a commercial wireless system using a system that does not require a wireless station license. However, systems that do not require radio station licenses also have the disadvantage of being susceptible to external factors such as communication restrictions due to congestion and communication service outages.
Therefore, in highly public industries that require high quality (firefighting, disaster prevention administration, railways, etc.), privately operated wireless communication infrastructure that requires a radio station license is used.

[Configuration of conventional wireless communication system and line control device: Figure 8]
A configuration example of a conventional wireless communication system and line control device will be explained using FIG. 8. FIG. 8 is an explanatory diagram showing a configuration example of a conventional wireless communication system and line control device.
As shown in FIG. 8, a conventional wireless communication system used as a business wireless system includes a line control device 1, command consoles 2a and 2b (sometimes referred to as command console 2), base stations 3a and 3b, 3c (sometimes referred to as a base station 3), and a plurality of mobile stations 4.
Further, various devices such as a FAX (facsimile) and a PBX (Private Branch Exchange) may be included in the equipment configuration, but they are omitted in this example.

Each part of a conventional wireless communication system will be explained.
The command console 2 has a function to smoothly carry out command tasks that are particularly important in business operations, such as simultaneous commands for all mobile stations 4 and interruptions in calls between mobile stations 4 in a commercial radio system. has. It also has functions to manage communications on the wireless communication system, such as monitoring and forcibly disconnecting calls occurring on the system.

The base station 3 is connected by wire to the line control device 1 and has a relay function for wireless communication between the mobile stations 4 and between the mobile station 4 and a wired desk (not shown).
The mobile station 4 mainly moves on land and performs wireless communication with other mobile stations 4 and the command desk 2 via the base station 3 .

The line control device 1 is the core device of the commercial radio system, and has a line control function to establish a communication path for voice/data transfer in response to requests from the command center 2, base station 3, and mobile station 4. .
Furthermore, the line control device 1 includes a call control section 11 , a line switching section 12 , a physical IF conversion section 13 , and a management monitoring control section 14 .

The management monitoring control unit 14 monitors the call control unit 11, line switching unit 12, and physical IF conversion unit 13 for failures.
The call control unit 11 performs call control such as origination, reception, response, and disconnection. Specifically, it mediates control data (communication requests, etc.) from the command console 2, mobile station 4, etc., and sends a line switching unit to the line switching unit 12 to connect the lines of the communication request source and the communication request destination. Outputs control instructions.

The line switching unit 12 controls the connection and disconnection of communication lines, and switches the route for transferring voice data in response to a line switching control command from the call control unit 11.
The physical IF conversion unit 13 connects the line control unit 1 and peripheral devices such as the command console 2 and the base station 3, and performs termination of various physical IFs. Specifically, analog lines, digital lines, and LAN lines corresponding to each command console 2 and base station 3 are connected to the line control device 1. Depending on the system configuration, it may be connected to various peripheral devices such as a FAX, a PBX (private branch exchange), and a dedicated telephone with a unique interface.

In conventional line control devices, connections are made using a dedicated physical IF conversion board depending on the physical interface.
In the example of FIG. 8, the physical IF conversion unit 13 includes physical IF conversion boards 13a to 13e.
Physical IF conversion boards 13a and 13d are for analog lines, physical IF conversion boards 13b are for digital lines, and physical IF conversion boards 13c and 13e are for LAN lines.

[Example of configuration of physical IF conversion board: Figure 9]
An example of the configuration of a physical IF conversion board in a conventional line control device will be described with reference to FIG. FIG. 9 is an explanatory diagram showing a configuration example of a conventional physical IF conversion board, in which (a) shows the configuration of the physical IF conversion board 13a shown in FIG. 8, and (b) shows the configuration of the physical IF conversion board 13b. The composition is as follows.
As shown in FIGS. 9(a) and 9(b), the physical IF conversion board (physical IF conversion board A) 13a includes a control section 31 and an analog IF conversion section 32. The IF conversion board B) 13b includes a control section 31 and a digital IF conversion section 33.
In other words, a board was provided for each type of IF converter.

The analog IF converter 32 connects to an analog line to perform physical IF conversion, and the digital IF converter 33 connects to a digital line to perform physical IF conversion.
The control unit 31 has a common configuration in the physical IF conversion boards 13a, 13b and other physical IF conversion boards 13c to 13e, and exchanges control data with the call control unit 11 and exchanges voice data with the line switching unit 12. I do.
In this manner, the physical IF conversion unit 13 uses a common interface for internal device communication such as control data and audio data, thereby making it possible to easily rearrange the physical IF conversion board.

[Operation when a failure occurs]
The operation when a failure occurs in a conventional line control device will be explained.
The operation when a failure occurs differs depending on the location where the failure occurs.
For example, if a failure occurs in any physical IF conversion board (sometimes simply referred to as a board) of the physical IF conversion unit 13, the range of influence on the system is limited to the connection destination of the failure board.

If the base station 3 is connected to the board in which the fault has occurred, the base station 3 performs return communication between the mobile stations 4 . In other words, communication between mobile stations 4 existing within the radio range of the base station 3 is realized by looping back at the base station 3 without going through the line control device 12 .
On the other hand, the command console 2, the base station 3 connected to other boards, and the line control unit 12 continue to operate.

If the command console 2 is connected to the faulty board, the command console 2 is disconnected from the system, and the command console 2, base station 3, and line control unit 12 connected to the normal board continue to operate.

In addition, if a failure occurs in the call control unit 11 or switching control unit 12, it will be difficult to continue operating the line control function, so all base stations 3 and line control equipment 12 are logically disconnected from each other. Station 3 performs degenerate operation using return communications.
As a result, if a failure occurs in the call control unit 11 or exchange control unit 12, the command console 2 will be unable to communicate with the mobile station 4.

[Related technology]
In addition, as conventional technologies related to line control devices and wireless communication systems, Japanese Patent Application Laid-Open No. 2014-82730 "Wireless Communication System" (Patent Document 1) and Japanese Patent Application Publication No. 2006-340165 "Communication Route Switching Control System and Router Device" (Patent Document 2).

Patent Document 1 discloses that when a communication failure occurs between a base station and a line control device, relay stations under the base station are wirelessly connected to each other, and mobile stations are connected to each other via a base station with no communication failure. It is stated that communication is possible.
Patent Document 2 describes that when a line failure is detected in a communication route currently in use, a communication route that bypasses the line failure is searched for, and switching to the searched communication route is performed.

Japanese Patent Application Publication No. 2014-82730 Japanese Patent Application Publication No. 2006-340165

As mentioned above, in conventional line control equipment, if a failure occurs in the call control unit or line switching unit, communication between the command center and the mobile station becomes impossible. There was a problem in that instructions could not be communicated to the bureau, which seriously affected business operations.

Furthermore, Patent Document 1 and Patent Document 2 disclose that when a failure occurs in the call control unit or the line switching unit, a simultaneous voice notification is sent from the command center to the mobile stations without going through the call control unit or the line switching unit. There is no description of what to do.

The present invention has been developed in view of the above-mentioned circumstances, and even when a failure occurs in the call control unit or line switching unit, resulting in degraded operation, it is possible to transmit instructions from the command center to the mobile station, and to continue operations. It is an object of the present invention to provide a line control device and a wireless communication system that can suppress the influence of noise and improve system reliability.

The present invention to solve the problems of the conventional example described above provides a line control device that performs line control in communication between a base station that performs wireless communication with a mobile station and a command station that outputs commands to the mobile station. There is a line switching unit that connects the line, a call control unit that controls the line switching unit based on input control data, and a function that instructs degenerate operation if a failure is detected in the line switching unit or the call control unit. A management monitoring control unit that outputs a degenerate mode signal to perform degeneracy, and a physical interface conversion unit that converts the physical interface between the base station and the command station. A first bus control unit that performs bus control of data; a second bus control unit that is connected to the call control unit and performs bus control of control data; and stores bus control information for voice data and control data in degenerate mode. The first bus control unit switches to the degeneracy mode when the degenerate mode signal is input, and stores the destination of the audio data transmitted from the command station on the bus stored in the storage unit. It is characterized in that it is rewritten based on control information, output to the base station without going through the circuit switching unit, and transmitted all at once.

Further, in the above-mentioned line control device, the present invention provides that the second bus control unit shifts to the degenerate mode when the degenerate mode signal is input, and stores the destination of the control data transmitted from the command station in the storage unit. Based on the stored bus control information, the data is rewritten to be output to the base station without going through the call control unit, and the destination of control data sent from the mobile station is changed based on the bus control information without going through the call control unit. The feature is that it can be rewritten to output to the command station.

The present invention also provides a wireless communication system comprising any of the above line control devices, a base station that performs wireless communication with a mobile station, and a command station that outputs commands to the mobile station. It is characterized by

According to the present invention, there is provided a line control device that performs line control in communication between a base station that performs wireless communication with a mobile station and a command station that outputs commands to the mobile station, the line switching device that performs line connection. a call control unit that controls the line switching unit based on input control data; and a management monitoring unit that outputs a degeneration mode signal instructing degenerate operation when a failure in the line switching unit or call control unit is detected. The physical interface converter includes a controller and a physical interface converter that converts the physical interface between the base station and the command station, and the physical interface converter is connected to the line switching unit and controls the voice data bus. It has a bus control unit, a second bus control unit that is connected to the call control unit and performs bus control of control data, and a storage unit that stores bus control information of voice data and control data in a degenerate mode. When the degenerate mode signal is input, the bus control unit of No. 1 shifts to the degenerate mode, rewrites the destination of the audio data sent from the command station based on the bus control information stored in the storage unit, and connects the line. Since the line control device outputs the output to the base station and transmits all at once without going through the switching section, even if a failure occurs in the call control section or the line switching section, instructions from the command center to the mobile stations can be sent simultaneously by voice. This can be communicated through reporting, which has the effect of reducing the impact on business operations and improving system reliability.

Further, according to the present invention, the second bus control unit shifts to the degenerate mode when the degenerate mode signal is input, and sets the destination of the control data transmitted from the command station to the bus stored in the storage unit. Based on the control information, rewrite to output to the base station without going through the call control unit, and output the destination of control data sent from the mobile station to the command station without going through the call control unit, based on the bus control information. Even if a failure occurs in the call control unit, it is possible to exchange information between the control center and mobile stations using short messages, which are control data, and improve business operations. This has the effect of suppressing the impact and improving system reliability.

Further, according to the present invention, the wireless communication system includes any one of the line control devices described above, a base station that performs wireless communication with a mobile station, and a command station that outputs commands to the mobile station. Even if a failure occurs in the call control unit or line switching unit, instructions can be transmitted from the command center to the mobile stations via voice broadcast, reducing the impact on business operations and improving system reliability. There is an effect that can be used.

FIG. 2 is a configuration block diagram of the present wireless communication system and the present line control device. FIG. 2 is an explanatory diagram showing a configuration example of a physical IF conversion section of the present line control device. FIG. 2 is an explanatory diagram showing the configuration of an IF control section of the present line control device. FIG. 2 is an explanatory diagram showing a communication establishment sequence from a command console to a mobile station during normal times. FIG. 3 is an explanatory diagram showing the route of audio data and control data during normal times. FIG. 2 is an explanatory diagram showing a communication establishment sequence in degenerate mode. FIG. 3 is an explanatory diagram showing a route of audio data and control data in a degenerate mode. FIG. 2 is an explanatory diagram showing a configuration example of a conventional wireless communication system and a line control device. FIG. 2 is an explanatory diagram showing a configuration example of a conventional physical IF conversion board.

Embodiments of the present invention will be described with reference to the drawings.
[Overview of embodiment]
A line control device (this line control device) and a wireless communication system (this wireless communication system) according to an embodiment of the present invention includes a bus control section provided in a physical IF conversion section that performs physical interface conversion with peripheral devices. , as route information in degenerate operation, it stores route information for outputting voice data from the command console to the base station without going through the call control unit and line switching unit, and the degenerate mode is set by the management monitoring and control unit. In this state, when a request for a voice call is made from the command center, the bus control unit rewrites the destination of the voice data from the command center according to the stored route information, and sends the voice data to the base without going through the call control unit or line switching unit. It outputs to the station and sends a simultaneous notification to the mobile stations (broadcast communication), so even if a failure occurs in the call control unit or line switching unit, instructions can be transmitted from the command center to the mobile stations. This can reduce the impact on business operations and improve system reliability.

In addition, this line control device and this wireless communication system allow the physical IF conversion unit to send control data sent from the control console to the base station as route information in degenerate operation without going through the call control unit or line switching unit. The control data output and sent from the base station stores the route information to be output to the command console, and the control data is input to the bus control unit with the degenerate mode set from the management monitoring control unit. This method rewrites the destination of the control data and sends and receives control data between the command center and the base station without going through the call control unit and line switching unit, and if a failure occurs in the call control unit. However, it enables the exchange of information between the command center and mobile stations via short messages, which reduces the impact on business operations and improves system reliability.

[Configuration of this wireless communication system and this line control device: Figure 1]
The configuration of this wireless communication system and this line control device will be explained using FIG. 1. FIG. 1 is a block diagram of the configuration of the present wireless communication system and the present line control device.
As shown in FIG. 1, this wireless communication system has the same basic configuration as the conventional wireless communication system shown in FIG. base stations 3a, 3b, 3c (also referred to as base stations 3), and a plurality of mobile stations 4.
The command console 2, base station 3, and mobile station 4 are the same as conventional ones, and their explanations will be omitted.

The line control device (this line control device) 5 includes a call control section 51, a line switching section 52, a management monitoring control section 54, and a physical IF conversion section 7.
Among these components, the call control section 51 and the line switching section 52 are the same as those in the conventional system, and their explanation will be omitted.

The management monitoring control section 54 monitors each section within the device to detect failures, as in the past, and as a feature of the line control device 5, it detects failures in the call control section 51 and/or the line switching section 52. In this case, a degenerate mode signal is output to the IF controllers 71 and 72 of the physical IF converter 7 to instruct degenerate operation (degenerate mode).
Furthermore, when the management monitoring control unit 54 detects that the call control unit 51 and/or the line switching unit 52, which had been in a failed state until then, have recovered from the failure, it outputs a degeneration mode release signal.

The physical IF converter 7 has a configuration and operation different from the conventional one, and is a characteristic part of the line control device 5.
Although details will be described later, in the example of FIG. 1, the physical IF conversion section 7 includes IF control sections 71 and 72 and a plurality of IF conversion sections 81 to 85.
The IF control section 71 is for analog lines and digital lines, and the IF control section 72 is for LAN lines, each of which can be connected to a plurality of IF conversion sections.
In normal times, the IF control units 71 and 72 appropriately route control the exchange of control data between the plurality of connected IF conversion units and the call control unit 51, and control the exchange of control data between the plurality of IF conversion units and the line switching unit 52. Route data exchange appropriately.

In FIG. 1, the IF control unit 71 is connected to an analog line IF conversion unit (analog IF conversion unit in the figure) 81, 84 and a digital line IF conversion unit (digital IF conversion unit) 82, and is connected to the IF control unit 71. LAN line IF conversion units (LAN IF conversion units) 83 and 85 are connected to the unit 72 .
Note that the IF converters 81 to 85 have the same configuration and operation as the conventional ones.

Further, the analog IF converter 81 is connected to the base station 3a via an analog line, the digital IF converter 82 is connected to the base station 3b via the digital line, and the analog IF converter 84 is connected to the base station 3b. A command console 2a is connected to the controller via an analog line.
Further, the base station 3c is connected to the LAN IF conversion section 85 via a LAN line, and similarly, the command console 2b is connected to the LAN IF conversion section 83.
A plurality of mobile stations 4 are wirelessly connected to each base station 3.

In the conventional physical IF conversion unit, as shown in FIG. 9, the control unit and the IF conversion unit were provided on a dedicated physical IF conversion board for each line. The unit 7 has a configuration in which a plurality of IF conversion units are connected to a common IF control unit.

[Example of configuration of physical IF converter of this line control device: Figure 2]
Here, an example of the configuration of the physical IF converter 7 in the line control device 5 will be described using FIG. 2. FIG. 2 is an explanatory diagram showing an example of the configuration of the physical IF conversion section of the line control device.
As shown in FIG. 2, the physical IF conversion unit 7 includes an IF control board 7a and a plurality of physical IF conversion boards 8a, 8b, and 8c.

An IF control section 70 is mounted on the IF control board 7a. The configuration and operation of the IF control unit 70 are characteristics of the line control device 5, and will be described later. The IF control unit 70 is an integrated unit of the above-mentioned IF control units 71 and 72, and performs route control of control data and audio data from a plurality of IF conversion units corresponding to analog lines, digital lines, and LAN lines. It is something.

In the example of FIG. 2, the physical IF conversion board 8a is equipped with an analog IF conversion section 81, the physical IF conversion board 8b is equipped with a digital IF conversion section 82, and the physical IF conversion board 8b is equipped with a digital IF conversion section 82. is equipped with a LAN IF conversion section 83.

[Configuration of IF control unit: Figure 3]
Next, the configuration of the IF control section 70 of the physical IF conversion section 7 will be explained using FIG. 3. FIG. 3 is an explanatory diagram showing the configuration of the IF control section of this line control device.
As shown in FIG. 3, the IF control unit 70 includes bus control units 73, 74, audio/control multiplexing/demultiplexing units 75a, 75b, ... (sometimes referred to as audio/control multiplexing/demultiplexing unit 75), and degenerate The mode route information storage section 77 is also provided.
Here, the audio/control demultiplexer 75 is provided corresponding to each IF converter connected to the IF controller 70, and in the case of the IF controller 70 shown in FIG. Although three parts are provided, only two are shown in FIG. 3 to simplify the explanation.

The bus control unit 73 is connected to the call control unit 51 and performs bus control of control data. The bus control section 73 corresponds to a second bus control section described in the claims.
The bus control unit 74 is connected to the line switching unit 52 and performs bus control of audio data. The bus control section 74 corresponds to a first bus control section described in the claims.
As a feature of the present line control device 5, the bus control units 73 and 74 internally hold normal mode or degenerate mode as operation mode information. The normal mode is set as the operating mode by default, but when a degenerate mode signal is input from the management monitoring control unit 54, the operational mode is switched (set) to the degenerate mode.

The bus control units 73 and 74 perform bus control according to the destination information attached to the data in normal times (in the case of normal mode), but when the degenerate mode is set, the degenerate mode route information storage unit Bus control is performed according to the route information stored in 77.
Specifically, the bus control unit 73 rewrites (overwrites) the destination information added to the control data based on the route information stored in the degraded mode route information storage unit 77. Forcibly change the destination.

Similarly, the bus control unit 74 forcibly changes the destination by rewriting the destination information added to the audio data based on the route information stored in the degenerate mode route information storage unit 77.
Further, when a degenerate mode release signal is input from the management monitoring control unit 54 while the degenerate mode is set, the bus control units 73 and 74 switch the operation mode to the normal mode, and the call control unit 51 and line This is a route for transmitting and receiving data via the control unit 52.

The degenerate mode route information storage unit 77 stores information that defines bus control (degenerate mode route) in the bus control units 73 and 74 when the degenerate mode is set.
The degenerate mode route information storage unit 77 stores degenerate mode route information so that audio data from the command console 2 is output to all base stations 3. As a result, in the degenerate mode, a simultaneous voice notification is performed from the command console 2 to the mobile stations 4.

In addition, the degenerate mode route information storage unit 77 stores degenerate mode route information for outputting control data from the command console 2 to the base station 3, and outputs control data from each base station 3 to the command console 2. Degenerate mode route information is stored so that
As a result, when a short message using control data is input from the mobile station 4 or the command console 2, it is output to the destination without going through the call control unit 11, and the short message is used to communicate between the command console 2 and the mobile station 4. Individual communication will take place between them.

The audio/control demultiplexers 75a and 75b separate the multiplexed audio data and control data input from the IF converter, output the audio data to the bus controller 74, and output the control data to the bus controller 74. 73.
Furthermore, the audio/control multiplexing and demultiplexing units 75a and 75b multiplex audio data input from the bus control unit 74 and audio data input from the bus control unit 73, and output the multiplexed data to the connected IF conversion unit.

[Communication establishment sequence from command center to mobile station (normal time): Figure 4]
Next, a communication establishment sequence from the command console 2 to the mobile station 4 in normal times (in a state where no failure has occurred) will be described using FIG. 4. FIG. 4 is an explanatory diagram showing a communication establishment sequence from the command console to the mobile station in normal times.
In FIG. 4, the command console 2a of FIG. 1 is connected to the audio/control demultiplexing section 75b of FIG. 3 via an IF conversion section, and the command console 2a of FIG. The case where the base station 3a is connected is shown. Here, it is assumed that both the command console 2a and the base station 3a are connected to an analog line, but they may be connected to a digital line or a LAN line.

As shown in FIG. 4, when a request for communication with the mobile station 4 is output from the command console 2, the IF control section 70 of the line control device 5 outputs a request for communication with the mobile station 4 to the call control section 51. .
The call control unit 51 identifies the base station 3a where the communication partner mobile station 4 included in the communication request exists, and transmits a call setup message to the base station 3a in order to establish a communication channel with the mobile station 4. .

The call setup message is received by the base station 3 via the IF control unit 70, and the base station 3 performs paging to the target mobile station 4, receives the incoming call status response from the mobile station 4, and 4 is in a state where the call can be received, it returns a call setting acceptance message to the IF control unit 70 of the line control device 5.
Then, the IF control unit 70 outputs a call setting acceptance message to the call control unit 51.
Furthermore, the base station 3a determines a wireless channel to be used for communication, and notifies the mobile station 4 of a wireless channel designation message.
This is the sequence for establishing a communication channel.

The mobile station 4 then switches the frequency to the designated radio channel, transmits a paging message to the base station 3a, and performs a response confirmation sequence with the call control unit 51.
When the call control unit 51 of the line control device 5 confirms the response from the mobile station 4, as a line control sequence, the call control unit 51 of the line control device 5 sends a line to the line switching unit 52 to connect the voice line between the base station 3a and the command console 2a. Send exchange control messages.

The line switching unit 52 connects the designated voice line according to the line switching control message (line switching).
This makes it possible to perform voice communication between the command console 2a and the mobile station 4 via the line control unit 52.
In this way, the normal communication establishment sequence is performed.

[Normal audio data/control data path: Figure 5]
Next, the normal audio data/control data path shown in FIG. 4 will be explained using FIG. 5. FIG. 5 is an explanatory diagram showing the route of audio data and control data during normal times. Note that FIG. 5 shows individual communication between the command center and the mobile station.
Further, in FIG. 5, the IF conversion unit provided between the IF control unit 70, the base station 3a, and the command console 2a is omitted.

As shown in FIG. 5, control data (indicated by dotted lines) transmitted and received during normal voice calls is transmitted from the command console 2a to the voice/control demultiplexer 75b to the bus control unit 73 to the call control unit 51 to the bus. The signal is transmitted and received bidirectionally along the route of control unit 73 - voice/control multiplexing/demultiplexing unit 75a - base station 3a - mobile station 4.
Further, a line switching control message output from the call control unit 51 is input to the line switching unit 52.

Similarly, after the line is established, the audio data indicated by the solid line is transmitted from the command console 2a to the audio/control multiplexer/demultiplexer 75b to the bus controller 74 to the line switching unit 52 to the bus controller 74 to the audio/control multiplexer/demultiplexer 75a. The data is transmitted and received in both directions along the route from base station 3a to mobile station 4.
That is, in normal times, control data is transmitted and received via the call control section 51, and voice data is transmitted and received via the line switching section 52.

[Communication establishment sequence in degenerate mode: Figure 6]
Next, the communication establishment sequence in the degenerate mode will be explained using FIG. 6. FIG. 6 is an explanatory diagram showing a communication establishment sequence in degenerate mode.
When a failure occurs in the call control unit 51 and/or the line switching unit 52 and a degeneration mode signal is output from the management monitoring control unit 54, the bus control units 73 and 74 of the IF control unit 70 degenerate the operation mode. mode, reads degenerate route information from degenerate mode route information storage section 77, and performs bus control.

As shown in FIG. 6, in the degenerate mode, when a communication request is output from the command console 2a to one of the mobile stations 4, the IF control unit 70 of the line control device 5 transmits the communication request to a call control unit. The call setting message is not output to the base station 51, but the destination information is rewritten to a broadcast message based on the degraded mode route information, and the call setup message is transmitted to all base stations 3. Then, each base station 3 transmits paging to all mobile stations 4 within its range, and if it is in a state where it can receive a call, transmits a call setup acceptance message to the line control device 5.

In the degenerate mode, the IF control section 70 accepts call setup and confirms the response with the mobile station 4 without outputting a call setup acceptance message to the call control section 51 .
Then, the IF control unit 70 does not control the line switching unit 52, but rewrites the destination of the voice data input from the command console 2 into a broadcast notification, outputs it to all base stations 3, and sends it to all base stations 3. A simultaneous notification is made to the mobile stations 4.
In this way, the communication establishment sequence in the degenerate mode is performed.

[Audio data/control data path in degenerate mode: Figure 7]
Next, the audio data/control data path in the degenerate mode shown in FIG. 6 will be explained using FIG. 7. FIG. 7 is an explanatory diagram showing the path of audio data and control data in the degenerate mode.
As shown in FIG. 7, in this line control device, the management monitoring control unit 54 monitors the call control unit 51 and line switching unit 52 for failures, and when a failure is detected, the management monitoring control unit 54 performs fault monitoring on the bus control units 73 and 74. A degenerate mode signal is output to the bus controllers 73 and 74, and the bus controllers 73 and 74 shift to the degenerate mode.

In the degenerate mode, as described above, voice data is transferred from the command console 2a to the voice/control multiplexer/demultiplexer 75b to the bus controller 74 to the voice/control multiplexer/demultiplexer 75a to the base station without going through the line switching unit 52. All base stations including mobile station 3a are notified at the same time via the mobile station 4 route.

In other words, the destination information attached to the voice data input from the command console 2a to the bus control unit 74 via the voice/control multiplexing unit 75b is transmitted from the line switching unit 52 to the bus control unit 74 to the voice/control multiplexing unit 75b. 75a - base station 3a - mobile station 4, but if the degenerate mode is set, the bus control unit 74 transmits the destination information of the audio data to all stations including the audio/control demultiplexer 75a - base station 3a. Rewrite (overwrite) base station 3 - all mobile stations 4.

As a result, even if a malfunction occurs in the call control unit 51 or line switching unit 52, instructions from the command console 2a are transmitted to all mobile stations 4, so that the impact on business performance can be suppressed. .

In addition to voice data, commercial wireless systems use dedicated wireless channels to exchange control information (control data), and control data includes simple text information called short messages. There is a mechanism to do so.
In the degenerate mode, control data is transmitted from the command console 2a to the voice/control demultiplexer 75b to the bus controller 73 to the voice/control demultiplexer 75a to the base station 2a to the mobile station 4 without going through the call controller 51. It is sent and received in both directions along this route.

For example, the destination information attached to the control data (short message) from the mobile station 4 inputted from the voice/control demultiplexer 75a to the bus control section 73 is: call control section 51 - bus control section 73 - voice/control The demultiplexer 75b--command console 2a is updated and output as the voice/control demultiplexer 75b--command console 2a so as not to go through the call control section 51. The same applies to control data from the command console 2a.
This allows communication between the mobile station 4 and the command console 2a using short messages even in the degenerate mode.

In this way, in the line control device 5, the IF control unit 70 stores the degenerate mode route information, and when the degenerate mode is set, the destination of voice data and control data can be rewritten according to the degenerate mode route information. , it is possible to ensure communication during degenerate operation, and since there is no need to change other components in the system (base station, command desk, etc.), it can be realized at low cost.

Note that when the management monitoring control unit 54 detects a failure in the physical IF conversion unit 7, the degeneracy mode signal is not output, and the degeneration mode is not set.
In this case, as in the past, if the command console 2 is connected to the failed IF converter, the command console 2 is disconnected from the system and the line is connected to the other command console 2 and base station 3. The control device 5 continues to operate normally.
Further, when the base station 3 is connected to the failed IF converter, the base station performs loopback communication between mobile stations, and the mobile stations connected to the base station 3 communicate with each other. The other base stations 3, command consoles 2, and line control devices 5 perform normal operations.

[Effects of embodiment]
According to the present line control device and wireless communication system, the IF control unit 70 of the physical IF conversion unit 7 that performs line connection includes a bus control unit 74 and a degraded mode route information storage unit that stores degraded mode route information in degraded operation. When a degeneracy signal is input from the management monitoring control section 54, the bus control section 74, which is equipped with 77 and performs bus control of voice data, sets the degeneration mode and when a request for voice communication is received from the command console 2. , rewrites the destination of the voice data from the command console 2 according to the degenerate mode route information stored in the degenerate mode route information storage unit 77, and outputs it to the base station 3 without going through the call control unit 51 and line switching unit 52. Since the line control device and wireless communication system are configured to send simultaneous notifications to the mobile stations 4, even if a failure occurs in the call control unit 51 or the line switching unit 52, instructions from the command console 2 to the mobile stations 4 can be sent to the mobile stations 4. This has the effect of reducing the impact on business operations and improving system reliability.

Further, according to the present line control device and the present wireless communication system, the control data transmitted from the command console 2 is transferred to the degenerate mode route information storage unit 77 from the mobile station without going through the call control unit 51 and the line switching unit 52. 4 and outputs the control data transmitted from the mobile station 4 to the command console 2 without going through the call control unit 51 and line switching unit 52, and performs bus control of the control data. When the bus control unit 73 receives a degeneration signal from the management monitoring control unit 54, it sets the degeneration mode, and when control data is input, it rewrites the destination of the control data according to the degeneration mode route information and makes a call. Since the line control device and wireless communication system is used to transmit and receive control data between the command console 2 and the mobile station 4 without going through the control unit 51 and line switching unit 52, if a failure occurs in the call control unit 51. However, it is possible to exchange information between the command center 2 and the mobile station 4 using short messages, which has the effect of suppressing the impact on business operations and improving the reliability of the system.

In particular, this line control device and wireless communication system can be applied to all private wireless communication systems such as disaster prevention wireless systems and commercial wireless systems, and the above-mentioned effects can be obtained regardless of the type of system. .

The present invention makes it possible to transmit instructions from the control console to the mobile station even if a failure occurs in the call control unit or line switching unit and the operation is degraded, thereby reducing the impact on operations and improving the system performance. It is suitable for line control devices and wireless communication systems that can improve reliability.

DESCRIPTION OF SYMBOLS 1, 5... Line control device, 2... Control console, 3... Base station, 4... Mobile station, 7, 13... Physical IF converter,... 11, 51... Call control unit, 12, 52... Line switching unit, 8a , 8b, 8c, 13a to 13e... Physical IF conversion board, 14, 54... Management monitoring control unit, 31... Control unit, 70, 71, 72... IF control unit, 73, 74... Bus control unit, 75a, 75b... Audio/control demultiplexing section, 77... Degenerate mode route information storage section, 81, 82, 83, 84, 85... IF conversion section

Claims (3)

A line control device that performs line control in communication between a base station that performs wireless communication with a mobile station and a command station that outputs commands to the mobile station,
A line switching section that performs line connections,
a call control unit that controls the line switching unit based on input control data;
a management monitoring control unit that outputs a degenerate mode signal instructing degenerate operation when a failure of the line switching unit or the call control unit is detected;
a physical interface conversion unit that converts a physical interface between the base station and the command station,
The physical interface conversion unit includes a first bus control unit that is connected to the line switching unit and performs bus control of voice data, and a second bus control unit that is connected to the call control unit and performs bus control of control data. and a storage unit for storing bus control information of audio data and control data in a degenerate mode,
When the degeneration mode signal is input, the first bus control section shifts to the degeneration mode, and determines the destination of the audio data transmitted from the command station based on the bus control information stored in the storage section. A line control device characterized in that it rewrites the data and outputs it to the base station without going through the line switching unit to transmit it all at once. When the second bus control unit receives the degeneracy mode signal, the second bus control unit shifts to the degeneracy mode and performs call control based on the bus control information stored in the storage unit, and determines the destination of the control data transmitted from the command station. and rewriting the destination of control data transmitted from the mobile station to be output to the command station without going through the call control unit, based on the bus control information. The line control device according to claim 1, characterized in that: A wireless communication system comprising the line control device according to claim 1 or 2, a base station that performs wireless communication with a mobile station, and a command station that outputs a command to the mobile station. .

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