JP7714962B2 - Line control device, line control method and program - Google Patents

Description

The present invention relates to a line control device, a line control method, and a program.

Air traffic control systems have become known in recent years (see, for example, Patent Document 1). In air traffic control systems, wireless communication with aircraft is carried out using wireless communication equipment installed in remote locations. This wireless communication equipment and the air traffic control system are connected via signal lines for audio signals and contact signals via transmission devices. The transmission devices are connected via 4W analog dedicated lines, and audio signals and contact signals are constantly being exchanged between the transmission devices.

Japanese Patent Application Laid-Open No. 2006-246292

However, in order to change from a 4W analog dedicated line to an Ethernet line without changing the interface specifications (4W analog signal) between transmission devices, it is necessary to use a VoIP gateway that supports an OD trunk interface to make the line change.

Therefore, it is desirable to provide technology that enables voice lines to be connected using automatic call control without the need to perform call origination or termination operations when using a VoIP gateway (hereinafter referred to as VoIP-GW (ODT)) that supports an OD trunk interface.

To solve the above problem, according to one aspect of the present invention, there is provided a line control device that includes a communication control unit that outputs an SS line on signal to a first gateway device connected to a first transmission device when the line control device is powered on, and the communication control unit outputs a dial signal to the first gateway device to control outgoing calls to a second gateway device connected to a second transmission device when a predetermined response signal to the line control device is output by the first gateway device.

If the SR line ON signal output from the first gateway device based on the completion of the call acceptance of the dial signal is not received for a predetermined time or longer, the communication control unit may output an SS line OFF signal to the first gateway device, output an SS line ON signal to the first gateway device again, and output the dial signal to the first gateway device based on the predetermined response signal to the line control device being output by the first gateway device.

When an SR line off signal is received from the first gateway device based on the occurrence of a fault in the line connecting the first gateway device and the second gateway device, the communication control unit may output an SS line off signal to the first gateway device, output an SS line on signal to the first gateway device again, and output the dial signal to the first gateway device based on the first gateway device again outputting the specified response signal to the line control device.

When an SR line off signal is received from the first gateway device based on the occurrence of a failure in another line control device connected to the second gateway device, the communication control unit may output an SS line off signal to the first gateway device, output an SS line on signal to the first gateway device again, and output the dial signal to the first gateway device based on the first gateway device again outputting the specified response signal to the line control device.

The communication control unit may output an SS line off signal to the first gateway device based on the occurrence of a failure in the line control device, and when an SR signal off signal is obtained from the first gateway device based on the SS line off signal, may output an SS line on signal to the first gateway device again, and may output the dial signal to the first gateway device based on the first gateway device re-outputting the specified response signal to the line control device.

The predetermined response signal may be a wink signal on the SR line.

The predetermined response signal may be a tone dial signal on the receiving signal line.

In addition, according to another aspect of the present invention, there is provided a line control method using a line control device, which includes: outputting an SS line on signal to a first gateway device connected to a first transmission device based on the line control device being powered on; and outputting a dial signal to the first gateway device for controlling outgoing calls to a second gateway device connected to a second transmission device based on the first gateway device outputting a predetermined response signal to the line control device.

In accordance with another aspect of the present invention, a program is provided that causes a computer to function as a line control device that includes a communication control unit that outputs an SS line on signal to a first gateway device connected to a first transmission device when the line control device is powered on, and the communication control unit outputs a dial signal to the first gateway device to control outgoing calls to a second gateway device connected to a second transmission device when a predetermined response signal to the line control device is output by the first gateway device.

According to another aspect of the present invention, there is provided a line control device comprising: a communication control unit that outputs a predetermined response signal to a second gateway device when an on signal of an SR line is output from a second gateway device connected to a second transmission device based on call control by a first gateway device connected to a first transmission device; and an acquisition unit that acquires a dial signal output from the second gateway device based on the output of the predetermined response signal , wherein the communication control unit outputs an on signal of an SS line to the second gateway device based on the acquisition of the dial signal by the acquisition unit, without outputting a signal for establishing a call connection to the second transmission device.

According to another aspect of the present invention, there is provided a line control method by a line control device, the line control method including: when an on signal for an SR line is output from a second gateway connected to a second transmission device based on call control by a first gateway connected to a first transmission device, outputting a predetermined response signal to the second gateway; acquiring a dial signal output from the second gateway based on the output of the predetermined response signal; and outputting an on signal for an SS line to the second gateway based on the acquisition of the dial signal without outputting a signal for establishing a call connection to the second transmission device .

According to another aspect of the present invention, there is provided a program for causing a computer to function as a line control device, the line control device comprising: a communication control unit that outputs a predetermined response signal to a second gateway device when an on signal of an SR line is output from a second gateway device connected to a second transmission device based on call control by a first gateway device connected to a first transmission device; and an acquisition unit that acquires a dial signal output from the second gateway device based on the output of the predetermined response signal, wherein the communication control unit outputs an on signal of an SS line to the second gateway device without outputting a signal for establishing a call connection to the second transmission device based on the acquisition unit's acquisition of the dial signal.

As described above, the present invention provides technology that enables voice lines to be connected using automatic call control without the need for call origination or termination operations when using a VoIP-GW (ODT).

FIG. 1 is a diagram illustrating an example of a conventional system configuration. FIG. 10 is a diagram illustrating another example of a conventional system configuration. 1 is a diagram illustrating an example of the configuration of a system according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a functional configuration of a line control device (master) according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a functional configuration of a line control device (slave) according to an embodiment of the present invention. FIG. 10 is a diagram showing a basic automatic connection control sequence according to an embodiment of the present invention. FIG. 10 is a diagram showing a re-originating connection sequence when the slave side has not yet started up when the master side has started up. FIG. 10 is a diagram showing a reconnection sequence in the event of a line failure. FIG. 10 is a diagram illustrating a reconnection sequence when a failure occurs on the slave side. FIG. 10 is a diagram illustrating a reconnection sequence when a failure occurs on the master side. 1 is a diagram illustrating a hardware configuration of an information processing device as an example of a line control device (master) according to an embodiment of the present invention.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Note that in this specification and drawings, components having substantially the same functional configuration will be designated by the same reference numerals, and redundant explanations will be omitted.

In addition, in this specification and drawings, multiple components having substantially the same functional configuration may be distinguished by adding different numbers after the same reference symbol. However, if there is no need to particularly distinguish between multiple components having substantially the same functional configuration, only the same reference symbol will be used. Furthermore, similar components in different embodiments may be distinguished by adding different letters after the same reference symbol. However, if there is no need to particularly distinguish between similar components in different embodiments, only the same reference symbol will be used.

(0. Overview of the embodiment)
First, an outline of the embodiment of the present invention will be described.

Figure 1 shows an example of a conventional system configuration. As shown in Figure 1, conventional system 8 includes a control console 81, a wireless voice switching control device 82, a transmission device 83, a transmission device 84, and wireless communication equipment 85.

In conventional system 8, voice signals and contact signals (PTT signals, SQ signals) were exchanged between wireless voice switching control device 82 and wireless communication device 85 via transmission device 83 and transmission device 84. Furthermore, in conventional system 8, contact signals were transmitted after being superimposed on voice signals, and transmission device 83 and transmission device 84 were connected only by a 4W analog dedicated line.

Figure 2 shows another example of a conventional system configuration. As shown in Figure 2, conventional system 9 includes a control console 91A, a wired voice switching control device 92A, a VoIP-GW (ODT) 93A, a VoIP-GW (ODT) 93B, a wired voice switching control device 92B, and a control console 91B.

In the conventional system 9, when wired communication was conducted between government offices A and B, the wired voice switching control device 92A and the wired voice switching control device 92B were connected by a 4W analog dedicated line, and when the 4W analog dedicated line between the wired voice switching control device 92A and the wired voice switching control device 92B was changed to an Ethernet line, the interfaces of the wired voice switching control device 92A and the wired voice switching control device 92B were changed to OD trunk interfaces.

To connect to an Ethernet line using an OD trunk interface, the wired voice switching control device 92A and VoIP-GW (ODT) 93A are connected using a 4W voice signal line as well as a control line (SS signal) and a monitoring line (SR signal). The operator's call origination operation or the call recipient's call response operation controls the SS and SR signals to connect the voice line, enabling calls to be made.

1, there is no call origination or termination operation between the air traffic control system and the wireless communication device 85, and it is necessary to keep the voice line connected at all times. Therefore, in order to connect to an Ethernet line using a VoIP-GW (ODT), it is desirable to maintain a call connection (line connection) between the VoIP-GW (ODT) using automatic call origination control.
Furthermore, even if a sudden line failure, equipment failure, or maintenance causes an Ethernet line disconnection and a call between the VoIP-GW (ODT) is disconnected, it is desirable to restore the call connection through automatic reconnection control without human intervention.

In an embodiment of the present invention, we propose a line connection method that establishes call connections between VoIP-GW (ODT) through automatic outgoing and automatic answering control without requiring any outgoing or incoming call operations. Furthermore, in an embodiment of the present invention, we propose a line reconnection method that establishes call connections through automatic redialing and automatic answering control when an Ethernet line failure or other problem occurs and the call connection between VoIP-GW (ODT) is severed.

Next, an overview of an embodiment of the present invention was explained.

1. DETAILED DESCRIPTION OF THE EMBODIMENTS
The details of the embodiment of the present invention will now be described.

(1-1. System Configuration)
First, an example of the configuration of a system according to an embodiment of the present invention will be described. Fig. 3 is a diagram showing an example of the configuration of a system according to an embodiment of the present invention.

The air traffic control system comprises a control console (101) and a wireless voice switching control device (102). Voice signals from the control console (101) are input to the wireless voice switching control device (102), which then outputs the voice to transmission device #1 (103) connected to the wireless communication device (202) selected by the control console (101).

To connect to wireless communication equipment (202) installed in a remote location, the air traffic control system transmits the outgoing voice signal (112) and PTT signal (110) from the wireless voice switching control device (102), the received voice signal (113) and SQ signal (111) from the wireless communication equipment (202) via transmission device #1 (103) and transmission device #2 (203) installed opposite each other. Transmission device #1 (103) and transmission device #2 (203) can be connected via a 4W analog dedicated line (114, 214).

Transmission device #1 (103) and transmission device #2 (203) are connected by a 4W analog dedicated line, and audio signals and contact signals are transmitted using 4W analog signals (114, 214) that superimpose PTT and SQ signals on the audio signal. The outgoing voice signal (212) from transmission device #2 (203) is transmitted to the wireless communication device (202), and a PTT signal (short for push-to-talk signal) (210) for transmission control enables communication with the airplane (201).

The voice signal from the airplane (201) is transmitted from the wireless communication device (202) to transmission device #2 as a received voice signal (213), then transmitted to transmission device #1 together with an SQ signal (short for squelch signal) (211) for reception control, and then transmitted to the control console (101) via the wireless voice switching control device (102).

In order to convert the 4W analog dedicated line connecting transmission device #1 (103) and transmission device #2 (203) to an Ethernet line, VoIP-GW (ODT) #1 (105) and VoIP-GW (ODT) #2 (205) are installed between transmission device #1 (103) and transmission device #2 (203), and the 4W analog signal is converted to an IP signal for transmission.

The VoIP-GW (ODT) is a VoIP gateway compatible with the OD trunk interface, and enables voice communication over Ethernet lines by controlling calls between VoIP-GWs (ODTs). Call control requires control of the SS signal (control line) (115, 215) and the SR signal (monitoring line) (116, 216), and line control devices (104, 204) are installed to control the SS signal (115, 215) and SR signal (116, 216).

More specifically, the line control device (104) is the line control device (master) (104), and the line control device (204) is the line control device (slave) (204). The line control device (master) (104) performs automatic outgoing processing, and the line control device (slave) (204) performs automatic answering processing.

The SS signal 1 (115) on the line control device (master) (104) side is used as a transmission signal, and the SR signal 1 (116) is used as a response signal indicating that a response has been made on the line control device (slave) (204) side and as a line connection signal indicating that the IP line is connected.

The SR signal 2 (216) on the line control device (slave) (204) side is used as an incoming call signal indicating that a call has been made on the line control device (master) (104) side and as a line connection signal indicating that an IP line is connected, and the SS signal 2 (215) is used as an incoming call response signal for incoming calls from the line control device (master) (104) side.

In an embodiment of the present invention, the line control device (master) (104) and the line control device (slave) (204) enable automatic connection by controlling and monitoring the SS and SR signals between each line control device and the VoIP-GW (ODT) to which they are connected.

Furthermore, in an embodiment of the present invention, it is possible to detect line disconnection by monitoring the SR signal on both the line control device (master) (104) side and the line control device (slave) (204) side. Furthermore, in an embodiment of the present invention, when a line disconnection is detected, the line is first cleared (empty) and then the line control device (master) (104) again controls the call, enabling automatic reconnection.

The above describes an example system configuration according to an embodiment of the present invention.

(1-2. Functional configuration of line control device (master))
Next, an example of the functional configuration of the line control device (master) (104) according to an embodiment of the present invention will be described. Fig. 4 is a diagram showing an example of the functional configuration of the line control device (master) (104) according to an embodiment of the present invention. As shown in Fig. 4, the line control device (master) (104) includes a control unit (104a), a storage unit (104d), and a communication unit (104e).

The control unit (104a) includes a CPU (Central Processing Unit) and other components, and its functions can be realized by the CPU expanding a program stored in the storage unit (104d) into RAM (Random Access Memory) and executing it. In this case, a computer-readable recording medium on which the program is recorded can also be provided. Alternatively, the control unit (104a) may be configured with dedicated hardware or a combination of multiple pieces of hardware.

As shown in FIG. 4, the control unit (104a) includes an acquisition unit (104b) and a communication control unit (104c). Details of each of these functional units of the control unit (104a) will be described later.

The memory unit (104d) is a storage device capable of storing programs and data for operating the control unit (104a). The memory unit (104d) can also temporarily store various data required during the operation of the control unit (104a). For example, the storage device may be a non-volatile storage device.

The communication unit (104e) is composed of a communication interface and communicates with VoIP-GW (ODT) #1 (105).

The above describes the functional configuration of the line control device (master) (104) according to an embodiment of the present invention.

(1-3. Functional configuration of line control device (slave))
Next, an example of the functional configuration of the line control device (slave) (204) according to an embodiment of the present invention will be described. Fig. 5 is a diagram showing an example of the functional configuration of the line control device (slave) (204) according to an embodiment of the present invention. As shown in Fig. 5, the line control device (slave) (204) includes a control unit (204a), a storage unit (204d), and a communication unit (204e).

The control unit (204a) includes a CPU (Central Processing Unit) and other components, and its functions can be realized by the CPU expanding a program stored in the storage unit (204d) into RAM (Random Access Memory) and executing it. In this case, a computer-readable recording medium on which the program is recorded can also be provided. Alternatively, the control unit (204a) may be configured with dedicated hardware, or a combination of multiple pieces of hardware.

As shown in FIG. 5, the control unit (204a) includes an acquisition unit (204b) and a communication control unit (204c). Details of each of these functional units of the control unit (204a) will be described later.

The memory unit (204d) is a storage device capable of storing programs and data for operating the control unit (204a). The memory unit (204d) can also temporarily store various data required during the operation of the control unit (204a). For example, the storage device may be a non-volatile storage device.

The communication unit (204e) is composed of a communication interface and communicates with VoIP-GW (ODT) #2 (205).

The above describes the functional configuration of the line control device (slave) (204) according to an embodiment of the present invention.

(1-4. System Operation)
Next, an example of the operation of the system according to the embodiment of the present invention will be described. As an example of the system operation, detailed operations of automatic connection control and detailed operations of automatic reconnection control when a line is disconnected due to a failure will be described.

(Automatic connection control)
6 is a diagram showing a basic sequence of automatic connection control according to an embodiment of the present invention. In this embodiment of the present invention, automatic connection is enabled by controlling the SS signal and SR signal to the VoIP-GW (ODT) in the line control device.

The operation of the line control device consists of two operations: master operation and slave operation. Master operation is an operation that automatically controls outgoing calls when the power is turned on, with the master side acting as the origin and connecting the line. Slave operation is an operation that automatically answers an incoming call when it detects an incoming call from the master side while waiting for an incoming call from the master side when the power is turned on. The basic line connection operation is explained in Figure 6.

In the line control device (master) (104), an automatic call process (S301) is performed when the power is turned on (power is turned on), and the communication control unit (104c) outputs SS signal 1 (S401) [ON] to VoIP-GW (ODT) #1 (105) based on the power start-up, thereby controlling the call.

When VoIP-GW (ODT) #1 (105) detects SS signal 1 (S401) from the line control device (master) (104), it outputs an [ON/OFF] pulse signal (wink signal) of SR signal 1 (S402) to the line control device (master) (104). Note that the wink start method is used here to exchange dialing information. However, as will be explained later, other methods for exchanging dialing information may also be used.

In the line control device (master) (104), the acquisition unit 104b acquires a wink signal from the VoIP-GW (ODT) #1 (105). Based on the wink signal acquired by the acquisition unit 104b, the communication control unit 104c outputs a dial signal 1 (S403) to the VoIP-GW (ODT) #1 (105). The dial signal 1 (S403) may be either a PB signal (push button signal) or a DP signal (dial pulse signal).

Upon receiving dial signal 1 (S403) from the line control device (master) (104), VoIP-GW (ODT) #1 (105) makes a call (S421) to the connected VoIP-GW (ODT) #2 (205).

The line control device (slave) (204) transitions to a state of waiting for an incoming call from the master side (waiting for an SR signal) immediately after power-on. VoIP-GW (ODT) #2 (205) receives call control (S421) from VoIP-GW (ODT) #1 (105) and outputs SR signal 2 (S411) to the line control device (slave) (204) [ON].

In the line control device (slave) (204), the acquisition unit 204b acquires an SR signal 2 (S411) from the VoIP-GW (ODT) #2 (205). Then, based on the acquisition of the SR signal 2 (S411) by the acquisition unit 204b, the communication control unit 204c outputs an [ON/OFF] pulse signal (wink signal) of the SS signal 2 (S412) to the VoIP-GW (ODT) #2 (205).

After receiving the wink signal from the line control device (slave) (204), VoIP-GW (ODT) #2 (205) outputs dial signal 2 (S413) to the line control device (slave) (204). Then, VoIP-GW (ODT) #2 (205) notifies VoIP-GW (ODT) #1 (105) that the call acceptance has been completed (S422).

In the line control device (slave) (204), the acquisition unit 204b acquires dial signal 2 (S413) from VoIP-GW (ODT) #2 (205). Then, based on the acquisition of dial signal 2 (S413) by the acquisition unit 204b, the communication control unit 204c outputs SS signal 2 (S414) [ON] to VoIP-GW (ODT) #2 (205).

When VoIP-GW (ODT) #2 (205) detects SS signal 2 (S414) from the line control device (slave) (204), it performs response control on VoIP-GW (ODT) #1 (105). The response control includes outputting an incoming call response (S423). In response to the response control from VoIP-GW (ODT) #2 (205), VoIP-GW (ODT) #1 (105) outputs SR signal 1 (S404) [ON] to the line control device (master) (104). VoIP-GW (ODT) #1 (105) outputs an incoming call response acceptance completion (S424) to VoIP-GW (ODT) #2 (205).

By detecting SR signal 1 (S404) from VoIP-GW (ODT) #1 (105), the line control device (master) (104) recognizes that the call connection has been completed and terminates the automatic call processing. With the call connection now complete, a 4W analog audio connection (S425) is established between transmission device #1 (103) and transmission device #2 (203) via the VoIP-GW (ODT), enabling communication of voice signals, PTT signals, and SQ signals.

(Reconnection)
Fig. 7 shows a re-originating connection sequence when the slave side has not yet started up when the master side is started up. The line re-connection operation in Fig. 7 will be explained. The operation of the line control device (master) (104) from power-on to output of dial signal 1 (S403) is the same as the basic line connection operation (Fig. 6).

After outputting dial signal 1 (S403), the line control device (master) (104) starts the [T1] timer (S405) and monitors the time until it detects a response signal from the slave side. The monitoring time (predetermined time) set in the [T1] timer may be preset to any fixed time. The monitoring time must be set appropriately depending on the system being used, but since it is necessary to take into account the network conditions, it is necessary to set the time on the order of a few seconds.

In the line control device (master) (104), if the acquisition unit 104b does not acquire a response signal from the slave side even after the monitoring time has elapsed, the communication control unit 104c determines that the line connection has not been completed and sets SS signal 1 (S406) to [OFF] to make the line available (S406). When SS signal 1 (S406) is set to [OFF], VoIP-GW (ODT) #1 (105) disconnects the line (S426), and VoIP-GW (ODT) #2 (205) sets SS signal 1 to [OFF] (S416).

The line control device (master) (104) sets the line status to idle, then starts the [T2] timer (S407), and after the [T2] time has elapsed, executes the redialing process (S302). The redialing process (S302) includes steps S431 to S433 and S427. However, steps S431 to S433 and S427 are the same as steps S401 to S403 and S421, which are included in the automatic redialing process S301.

If the slave side is up and running by the time of the redialing process (S302), the line will be connected by automatic response processing by the line control device (slave) (204), enabling communication of voice signals, PTT signals, and SQ signals between transmission device #1 (103) and transmission device #2 (203). The redialing process (S302) from the master side will be repeated until the slave side is up and running.

(Line failure)
8 is a diagram showing a reconnection sequence when a line failure occurs. The reconnection operation when the line is disconnected in FIG. 8 will be described.

If the network line between the VoIP-GW (ODT) is disconnected, VoIP-GW (ODT) #1 (105) turns OFF the SR signal 1 (S408) sent to the line control device (master) (104).

In the line control device (master) (104), when the acquisition unit 104b acquires an [OFF] SR signal 1 (S408) from VoIP-GW (ODT) #1 (105), the communication control unit 104c sets [OFF] the SS signal 1 (S406) to VoIP-GW (ODT) #1 (105), sets the line status to an idle state, starts the [T2] timer (S407), and transitions to a state waiting for retransmission processing (S302).

If the network line between the VoIP-GW (ODT) is disconnected, VoIP-GW (ODT) #2 (205) also turns OFF the SR signal 2 (S416) sent to the line control device (slave) (204).

In the line control device (slave) (204), when the acquisition unit 204b acquires an SR signal 2 (S416) set to [OFF] from the VoIP-GW (ODT) #2 (205), the communication control unit 204c sets the SS signal 2 (S418) to the VoIP-GW (ODT) #2 (205) to [OFF], changes the line state to an idle state, and then transitions to a state waiting for an incoming call from the master side.

After the time [T2] has elapsed, the line control device (master) (104) performs the redialing process (S302), and when the slave side automatically responds, the line is reconnected, enabling communication of voice signals, PTT signals, and SQ signals between transmission device #1 (103) and transmission device #2 (203).

(Failure occurs on the slave side)
9 is a diagram showing a reconnection sequence when a failure occurs on the slave side. The reconnection operation when a failure occurs on the slave side in FIG. 9 will be described.

If a failure occurs in the line control device (slave) (204), powering off the line control device (slave) will cause SS signal 2 (S418) to be set to [OFF] for VoIP-GW (ODT) #2 (205). When VoIP-GW (ODT) #2 (205) detects that SS signal 2 (S418) from the line control device (slave) (204) is set to [OFF], it performs a disconnection process on VoIP-GW (ODT) #1 (105) (S461).

Based on the disconnection process from VoIP-GW (ODT) #2 (205), VoIP-GW (ODT) #1 (105) turns SR signal 1 (S408) to the line control device (master) (104) to [OFF].

In the line control device (master) (104), when the acquisition unit 104b acquires an SR signal 1 (S408) [OFF] from the VoIP-GW (ODT) #1 (105), the communication control unit 104c sets the SS signal 1 (S406) to [OFF] for the VoIP-GW (ODT) #1 (105), sets the line status to an idle state, starts the [T2] timer, and transitions to a state waiting for retransmission processing (S302).

When VoIP-GW (ODT) #1 (105) detects that the SS signal 1 (S406) from the line control device (master) (104) is OFF, it performs a disconnection process on VoIP-GW (ODT) #2 (205) (S462). Based on the disconnection process from VoIP-GW (ODT) #1 (105), VoIP-GW (ODT) #2 (205) sets the SR signal 2 (S416) to the line control device (slave) (204) to OFF, setting the line status to an idle state.

When the line control device (slave) (204) recovers from the failure and the line control device (slave) (204) is powered back on, the line control device (slave) (204) transitions to a state in which it waits for an incoming call response from the master side.

After the time [T2] has elapsed, the line control device (master) (104) performs the redialing process (S302), and when the slave side automatically responds, the line is reconnected, enabling communication of voice signals, PTT signals, and SQ signals between transmission device #1 (103) and transmission device #2 (203).

(Failure occurs on the master side)
10 is a diagram showing a reconnection sequence when a failure occurs on the master side. The reconnection operation when a failure occurs on the master side in FIG. 10 will be described.

If a failure occurs in the line control device (master) (104), powering off the line control device (master) will cause SS signal 1 (S406) to VoIP-GW (ODT) #1 (105) to turn OFF. When VoIP-GW (ODT) #1 (105) detects that SS signal 1 (S406) from the line control device (master) (104) has turned OFF, it performs a disconnection process on VoIP-GW (ODT) #2 (205) (S461).

Based on the disconnection process from VoIP-GW (ODT) #1 (105), VoIP-GW (ODT) #2 (205) sets SR signal 2 (S416) to the line control device (slave) (204) to [OFF]. In the line control device (slave) (204), when the acquisition unit 204b acquires the [OFF] SR signal 2 (S416) from VoIP-GW (ODT) #2 (205), the communication control unit 204c sets SS signal 2 (S418) to VoIP-GW (ODT) #2 (205) to [OFF] and transitions to a call response waiting state.

When VoIP-GW (ODT) #2 (205) detects that the SS signal 2 (S418) from the line control device (slave) (204) is OFF, it performs a disconnection process on VoIP-GW (ODT) #1 (105) (S462). Based on the disconnection process from VoIP-GW (ODT) #2 (205), VoIP-GW (ODT) #1 (105) sets the SR signal 1 (S408) to the line control device (master) (104) to OFF, setting the line status to an idle state.

When the line control device (master) (104) recovers from the failure and the power to the line control device (master) (104) is restored, a retransmission process (S302) to the slave side is performed, and when the slave side automatically responds, the line is reconnected, enabling communication of voice signals, PTT signals, and SQ signals between transmission device #1 (103) and transmission device #2 (203).

The above describes an example of the operation of a system according to an embodiment of the present invention.

(1-5. Effects)
As described above, the system according to the embodiment of the present invention enables call connections between VoIP-GWs (ODTs) through automatic call and answer control without the need for dedicated call origination and termination operations. Furthermore, even if a failure occurs in the Ethernet line or line control device, the system according to the embodiment of the present invention enables automatic line connection by controlling and monitoring the SS and SR signals. This provides a significant advantage in terms of maintainability of the voice lines of air traffic control systems.

In addition, the system according to an embodiment of the present invention is capable of reconnecting the line as soon as the failure is resolved, minimizing the impact on operations and improving reliability.

The above describes the effects achieved by the system according to an embodiment of the present invention.

(2. Hardware configuration example)
Next, an example of the hardware configuration of the line control device (master) (104) according to an embodiment of the present invention will be described.

Below, an example of the hardware configuration of the information processing device 900 will be described as an example of the hardware configuration of the line control device (master) (104) according to an embodiment of the present invention. Note that the example of the hardware configuration of the information processing device 900 described below is merely one example of the hardware configuration of the line control device (master) (104). Therefore, the hardware configuration of the line control device (master) (104) may be such that unnecessary components are deleted from the hardware configuration of the information processing device 900 described below, or new components may be added. Note that the hardware configuration of the line control device (slave) (204) can also be realized in the same way as the hardware configuration of the line control device (master) (104).

Figure 11 is a diagram showing the hardware configuration of an information processing device 900 as an example of a line control device (master) (104) according to an embodiment of the present invention. The information processing device 900 includes a CPU (Central Processing Unit) 901, a ROM (Read Only Memory) 902, a RAM (Random Access Memory) 903, a host bus 904, a bridge 905, an external bus 906, an interface 907, an input device 908, an output device 909, a storage device 910, and a communication device 911.

The CPU 901 functions as an arithmetic processing device and control device, and controls the overall operation of the information processing device 900 in accordance with various programs. The CPU 901 may also be a microprocessor. The ROM 902 stores programs used by the CPU 901, calculation parameters, etc. The RAM 903 temporarily stores programs used in the execution of the CPU 901, and parameters that change as appropriate during the execution. These are interconnected by a host bus 904, which is composed of a CPU bus, etc.

The host bus 904 is connected to an external bus 906, such as a PCI (Peripheral Component Interconnect/Interface) bus, via a bridge 905. Note that the host bus 904, bridge 905, and external bus 906 do not necessarily need to be configured separately; these functions may be implemented on a single bus.

The input device 908 is composed of input means for the user to input information, such as a mouse, keyboard, touch panel, buttons, microphone, switches, and levers, and an input control circuit that generates input signals based on user input and outputs them to the CPU 901. By operating this input device 908, the user operating the information processing device 900 can input various data to the information processing device 900 and instruct processing operations.

The output device 909 includes, for example, display devices such as a CRT (Cathode Ray Tube) display device, a liquid crystal display (LCD) device, an OLED (Organic Light Emitting Diode) device, a lamp, and an audio output device such as a speaker.

The storage device 910 is a device for storing data. The storage device 910 may include a storage medium, a recording device that records data on the storage medium, a reading device that reads data from the storage medium, and a deletion device that deletes data recorded on the storage medium. The storage device 910 is configured, for example, with an HDD (Hard Disk Drive). This storage device 910 drives the hard disk and stores programs executed by the CPU 901 and various data.

The communication device 911 is, for example, a communication interface configured with a communication device for connecting to a network. Furthermore, the communication device 911 may support either wireless communication or wired communication.

The above describes an example of the hardware configuration of the line control device (master) (104) according to an embodiment of the present invention.

(3. Summary)
Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art to which the present invention pertains can conceive of various modifications and alterations within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

For example, the above description has primarily focused on the case where a system according to an embodiment of the present invention targets wireless communication lines in an air traffic control system. However, a system according to an embodiment of the present invention can be applied to any system that uses a 4W analog dedicated line.

The above mainly describes the case where the wink start method is used to exchange dialing information. However, the method for exchanging dialing information is not limited to the wink start method. For example, the method for exchanging dialing information may be the pre-pause start method. In such a case, a tone dial signal on the receiving signal line may be used instead of the [ON/OFF] pulse signal (wink signal) of the SR signal.

101 control console 102 radio voice switching control device 103 transmission device 104 line control device (master)
104b Acquisition unit 104c Communication control unit 105 VoIP-GW (ODT)
202 wireless communication device 203 transmission device 204 line control device (slave)
204b Acquisition unit 204c Communication control unit 205 VoIP-GW (ODT)

Claims (12)

A line control device,
a communication control unit that outputs an SS line ON signal to a first gateway device connected to a first transmission device when the line control device is powered on;
The communication control unit
outputting, to the first gateway device, a dial signal for controlling an outgoing call to a second gateway device connected to a second transmission device, based on the first gateway device outputting a predetermined response signal to the line control device;
Line control device. The communication control unit
When an ON signal for an SR line output from the first gateway device based on completion of the outgoing call acceptance of the dial signal is not acquired for a predetermined time or longer, an OFF signal for an SS line is output to the first gateway device, and an ON signal for the SS line is output again to the first gateway device;
outputting the dial signal to the first gateway device based on the fact that the predetermined response signal to the line control device has been output by the first gateway device;
The line control device according to claim 1. The communication control unit
when an OFF signal of an SR line is acquired from the first gateway device based on the occurrence of a fault in a line connecting the first gateway device and the second gateway device, outputting an OFF signal of an SS line to the first gateway device and outputting an ON signal of the SS line to the first gateway device again;
outputting the dial signal to the first gateway device based on the fact that the predetermined response signal to the line control device has been output again by the first gateway device;
The line control device according to claim 1. The communication control unit
when an OFF signal of an SR line is acquired from the first gateway device based on the occurrence of a failure in another line control device connected to the second gateway device, outputting an OFF signal of an SS line to the first gateway device and outputting an ON signal of an SS line to the first gateway device again;
outputting the dial signal to the first gateway device based on the fact that the predetermined response signal to the line control device has been output again by the first gateway device;
The line control device according to claim 1. The communication control unit
outputting an OFF signal of an SS line to the first gateway device based on the occurrence of a fault in the line control device, and when an OFF signal of an SR signal is acquired from the first gateway device based on the OFF signal of the SS line, outputting an ON signal of the SS line to the first gateway device again;
outputting the dial signal to the first gateway device based on the fact that the predetermined response signal to the line control device has been output again by the first gateway device;
The line control device according to claim 1. The predetermined response signal is a wink signal on the SR line.
The line control device according to any one of claims 1 to 5. the predetermined response signal is a tone dial signal on a receiving signal line;
The line control device according to any one of claims 1 to 5. A line control method by a line control device,
outputting an SS line ON signal to a first gateway device connected to a first transmission device based on the fact that the line control device is powered on;
outputting, to the first gateway device, a dial signal for controlling an outgoing call to a second gateway device connected to a second transmission device, based on the first gateway device outputting a predetermined response signal to the line control device;
A line control method including: Computer,
A line control device,
a communication control unit that outputs an SS line ON signal to a first gateway device connected to a first transmission device when the line control device is powered on;
The communication control unit
outputting, to the first gateway device, a dial signal for controlling an outgoing call to a second gateway device connected to a second transmission device, based on the first gateway device outputting a predetermined response signal to the line control device;
A program that functions as a line control device. A line control device,
a communication control unit that outputs a predetermined response signal to a second gateway when an ON signal of an SR line is output from a second gateway connected to a second transmission device based on call control by a first gateway connected to a first transmission device;
an acquisition unit that acquires a dial signal output from the second gateway device based on the output of the predetermined response signal;
Equipped with
the communication control unit, based on the acquisition of the dial signal by the acquisition unit, outputs an SS line ON signal to the second gateway device without outputting a signal for establishing a call connection to the second transmission device.
Line control device. A line control method by a line control device,
outputting a predetermined response signal to a second gateway device when an ON signal of an SR line is output from a second gateway device connected to a second transmission device based on call control by a first gateway device connected to a first transmission device;
acquiring a dial signal output from the second gateway device based on the output of the predetermined response signal;
outputting an SS line ON signal to the second gateway device without outputting a signal for establishing a call connection to the second transmission device based on the acquisition of the dial signal;
A line control method including: Computer,
A line control device,
a communication control unit that outputs a predetermined response signal to a second gateway when an ON signal of an SR line is output from a second gateway connected to a second transmission device based on call control by a first gateway connected to a first transmission device;
an acquisition unit that acquires a dial signal output from the second gateway device based on the output of the predetermined response signal;
Equipped with
the communication control unit, based on the acquisition of the dial signal by the acquisition unit, outputs an SS line ON signal to the second gateway device without outputting a signal for establishing a call connection to the second transmission device.
A program that functions as a line control device.