JPH0728345B2 - Communication system with conference phone terminal - Google Patents

Description

DETAILED DESCRIPTION [Overview] In a communication system in which a subscriber telephone is connected to a digital network through a codec and a digital transmission line, and the connection between the subscriber telephones is controlled by controlling the digital network, a plurality of subscribers are connected. In order to realize the conference call connection between the party's telephones without the need for complicated equipment, the subscriber's telephones are connected to the conference telephone terminals via the codecs, and the conference telephone terminals respectively have incoming and outgoing lines. Have
Conference telephone connection in a configuration that can be connected to a digital transmission line through the B ₁ channel and B ₂ channel, and a connection between subscriber telephones including a conference telephone connection is formed by a digital network to which the digital transmission line is connected. In this case, the B ₁ channel of the conference telephone terminal device is the conference telephone terminal device of the adjacent subscriber telephone in the conference telephone connection, and the B ₂ channel is the conference telephone terminal of the other adjacent subscriber telephone in the conference telephone connection. An adder circuit that is connected to each device and adds the incoming call to that line to the incoming line of B ₁ channel and the incoming line of B ₂ channel to output to the codec,
The outgoing line is provided with an adder circuit that adds and outputs the output of its own codec and the incoming line of the B ₂ channel incoming line, and the incoming line of the B ₂ channel is a conference call of another subscriber's telephone adjacent to it. A signal from the terminal device is received and B ₁ , B ₂
An adder circuit is provided between the channels, and this adder circuit adds the output of its own codec and the incoming call to the incoming line of the B ₁ channel and outputs it to the outgoing line of the B ₂ channel.

[Industrial application field]

The present invention relates to a communication system including a conference telephone terminal device in which a subscriber telephone is connected to a digital network through a codec and a digital transmission line, and conference telephone connection between a plurality of subscriber telephones is also possible.

[Conventional technology]

FIG. 3 shows a conventional example. Subscriber telephones Ta, Tb, Tc are connected to a digital network DNW via corresponding codecs C ₁ , C ₂ , C ₃ and a digital transmission line, respectively, and are controlled by the digital network DNW. , Subscriber telephones can be connected via a 1-channel digital transmission line.

That is, when the subscriber telephone Ta sends the subscriber number of Tb to the digital network DNW, the DNW forms a connection path between the subscriber telephone Ta and Tb.

Further, in FIG. 3, a conference telephone device 10 is provided in common to all the subscriber telephones, and when each subscriber sends out the selection number of this conference telephone device to the digital network DNW, the subscriber telephones are also controlled by the control. Is connected to the conference telephone device via a 1-channel digital transmission line.

Therefore, when the subscriber telephone Ta makes a conference call connection between Tb and Tc, for example, Ta designates the time of the conference call connection to Tb and Tc in advance by the one-to-one control by the control of the digital network DNW.
By telling the connection of the subscriber telephone at the specified time
When Ta, Tb, and Tc respectively send the selected numbers of the conference telephone device 10 to the digital network DNW, each subscriber telephone is connected to the conference telephone device 10 by the control of the DNW, and the conference telephone connection is formed.

In this case, the voice signal from each subscriber telephone is digitally encoded by the codec and sent to the conference telephone device via the digital transmission line. Assuming that the digitally encoded voice signal from the subscriber telephone set Ta is A, the voice signal from Tb is B, and the voice signal from Tc is C, the conference telephone device receives the digitally encoded voice signal. Add and distribute according to the subscriber's telephone.

That is, in the conference telephone device 10, when the addition result of the digitally encoded voice signal such as (B + C) is sent to the subscriber telephone Ta side, it is decoded by the codec C ₁ and reaches the subscriber telephone Ta.

Similarly, the addition result of the digitally encoded voice signal such as (A + C) is sent to the subscriber telephone set Tb side, and (A + B)
Is sent to the subscriber telephone Tc side.

In this way, each of the subscriber telephones can make a conference call by receiving the voice signal from the subscriber telephones participating in the conference telephone connection via the conference telephone device.

[Problems to be solved by the invention]

However, since such a conference telephone device receives the digitally encoded voice signal from each subscriber telephone in a concentrated manner, it separately identifies each subscriber telephone and further identifies it for each subscriber telephone to be transmitted. The voice signals that need to be sent are separated and added, and the addition result is sent to the corresponding subscriber telephone.

Therefore, when the number of subscriber telephones participating in the conference telephone connection increases, the number of digitally encoded voice signals from each subscriber telephone also increases in the conference telephone device, and the separation identification and the voice corresponding to the subscriber telephone are performed. Signal addition processing and transmission of the respective addition results must be performed, which complicates control and device configuration, and limits the number of subscriber telephones that can participate in the conference telephone connection.

[Means for solving problems]

According to the present invention, the above-mentioned problem is that the subscriber telephone is connected to the conference telephone terminal device via the codec, and the conference telephone terminal device has the incoming line and the outgoing line, respectively.
In a configuration in which a connection between subscriber telephones including a conference telephone connection is formed by a digital network that can be connected to a digital transmission line through the B ₁ channel and the B ₂ channel and the digital transmission line is connected, In this case, the B ₁ channel of the conference telephone terminal device is the conference telephone terminal device of _one subscriber telephone that is adjacent in the conference telephone connection, and the B ₂ channel is the conference telephone terminal device of the other subscriber telephone that is adjacent in the conference telephone connection. The adder circuit connected to the incoming line of B ₁ channel and the incoming line of B ₂ channel and the incoming line of B ₂ channel are sent to the codec.
Also the outgoing line is provided adding circuit for adding and outputting the incoming output and B ₂ channel incoming line self codec, B ₂ channel incoming line adjacent other subscribers telephone conference call of the the A signal from the terminal device is received and B ₁ , B ₂
A conference call is provided between the channels, and the addition circuit adds the output of its own codec and the incoming call to the incoming line of B ₁ channel and outputs it to the outgoing line of B ₂ channel. It is solved by a communication system including a terminal device.

[Action]

In the present invention, the subscriber telephone is not connected to the digital transmission line via the codec, but the codec is further connected to the digital transmission line via the conference telephone terminal device.
In the case of conference telephone connection, for example, the conference telephone terminal device (CT ₂₂ ) of _one subscriber telephone is connected to the conference telephone terminal device (CT ₂₁ ) of one of the subscriber telephones adjacent to the B ₁ channel by the conference telephone connection, While receiving the digitally encoded voice signal (A) from the conference telephone terminal device, the conference telephone terminal device itself receives the digitally encoded voice signal (B) and the conference on the other side adjacent to the conference telephone connection. The digitally encoded voice signal (c + d) from the telephone terminal device (CT ₂₃ ) is transmitted.

Also, it is connected to the conference telephone terminal device (CT ₂₃ ) on the other side through a conference telephone connection via the B ₂ channel, receives a digitally encoded voice signal (c + d) from the conference telephone terminal device, and To the conference telephone terminal device, the own digitally encoded voice signal (B) and the digitally encoded voice signal (A) from the adjacent conference telephone terminal device are transmitted.

The B _1, B ₂ to the channel both provided with an incoming line and outgoing line, the incoming line of the B ₁ channel at each conference telephone terminal device, outgoing lines and B _1, B ₂ between the channels, each summing circuit 30, 31 and 32
The adder circuit 30 performs (A + C + D) addition, the adder circuit 31 performs (B + C + D) addition, and the adder circuit 32 performs (A + C).
By adding B), a conference call connection between a plurality of subscriber telephones is realized.

In the present invention, it is necessary to arrange a conference telephone terminal device for each subscriber telephone, but this device can be realized mainly by including only an adding circuit as described above, and a data terminal is connected to the conference telephone terminal device. When data communication is performed by using a selector, a selector for switching between telephone connection and data communication,
Even if the number of subscriber telephones connected to the conference telephone increases as long as the gate is provided, it is easy to connect the conference telephone terminal device having the simple structure as described above between the codec and the digital transmission line. You will be able to join the conference call connection.

〔Example〕

FIG. 1 is a block diagram of a conference telephone terminal device according to an embodiment of the present invention, and FIG. 2 is a block diagram of a communication system including the conference telephone terminal device of an embodiment of the present invention.

In FIG. 1, T is a subscriber telephone, C is a codec for digitally encoding a voice signal and decoding the digitally encoded voice signal, CT is a conference telephone terminal device,
B ₁ and B ₂ have B ₁ channel and B ₂ channel respectively having an incoming line and an outgoing line, 30 to 32 are addition circuits, 33 is a gate, 34 is a selector, 35 is an ISDN line interface device, and 36 is a line control device. , DT indicates a data terminal.

As shown in FIG. 2, each subscriber telephone set Ta, Tb, Tc, Td has a codec C ₁ , C ₂ , C ₃ , C ₄ , a conference telephone terminal device CT ₂₁ ,
Connected to CT ₂₂ , CT ₂₃ , CT ₂₄ ,
It is connectable to a digital transmission path via the B ₁ channel, B ₂ channel.

The connection control between the subscriber telephones connected to the digital transmission line is controlled by the digital network DNW to which the digital transmission line is connected, and the one-to-one correspondence between the subscribers.
In the case of the connection, only the B ₁ channel is used, and in the case of the conference telephone connection between a plurality of subscriber telephones, both the channels B ₁ and B ₂ are used.

A data terminal DT is also connected to the conference telephone terminal device CT as shown in the figure, and the conference telephone terminal device also has a function of switching between call connection between subscriber telephones or connection between respective subscriber data terminals, Connection between data terminals is also a data network DN
It becomes possible by controlling W.

Here, for example, in the case of a one-to-one connection between the subscriber telephones Ta and Tb, the subscriber telephone Tb sends out the subscriber number of the subscriber telephone Ta to the digital network DNW, so that the digital network DNAW has a B ₁ channel. A connection path between the subscriber's telephone set Tb and Ta is formed via the telephone line, and a one-to-one call connection between the subscriber's telephone set Tb and Ta becomes possible.

That is, in FIG. 1, assuming that the subscriber telephone set T is Tb, the voice signal from the subscriber telephone set Tb is digitally encoded by the codec C ₂ , and the summing circuit 31 of the transmission line is used by the conference telephone terminal device CT _2.
Sent to the B ₁ channel via. Since B ₁ channel is connected to the B ₁ channel of subscriber telephone Ta digital network DNW, audio signals digitally encoded from the subscriber telephone set Ta is B ₁ in this conference telephone terminal
The voice signal digitally encoded by the codec C ₂ is decoded through the addition circuit 30 of the incoming line of the channel, and is received by the subscriber telephone set Tb.

When it is desired to make a conference call including the subscriber telephone sets Tc and Td in such a connected state, the subscriber telephone set in FIG.
When Tb sends the subscriber number for subscriber telephone set Tc to digital network DNW, digital network D
In NW, the B ₁ channel of the subscriber telephone Tb is the subscriber telephone Ta
Since it is being used to connect to the conference telephone terminal device CT ₂₂ , the B ₂ channel of the conference telephone terminal device CT ₂₂ of the subscriber telephone Tb is connected to the B ₁ channel of the conference telephone terminal device CT ₂₃ of the subscriber telephone Tc.

After this connection path is formed, the subscriber telephone set Tc is replaced by the subscriber telephone set Td.
When the subscriber number of is sent to the digital network DNW, the digital network DNW sends the B ₂ channel of the conference telephone terminal device CT ₂₃ of the subscriber telephone Tc to the subscriber telephone Td.
The conference call terminal device CT ₂₄ is connected to the B ₁ channel to form a conference call connection path between the subscriber telephones Ta, Tb, Tc and Td as shown in FIG.

In such connection path, for example, a subscriber look for phone Tb when B ₁ channel of the conference telephone terminal CT ₂₂ is connected to the conference call terminal CT ₂₁ of the subscriber telephone Ta, also B ₂ channels of subscriber telephone Tc Connected to the conference phone terminal CT ₂₃ .

Therefore, FIG. 1 shows the conference telephone terminal device CT _{22 of the} subscriber telephone Tb.
Then, the digitally encoded voice signal from the conference telephone terminal device CT ₂₁ arrives at the incoming line of the B ₁ channel of the ISDN line which is a digital transmission line. Then on CT ₂₂
Since only the CT ₂₁ is connected, only the digitally encoded voice signal (A) from the subscriber's telephone set Ta arrives at the incoming line and is input to the adding circuit 30.

In addition, on the B ₁ channel transmission line, the voice signal digitally encoded by the codec C ₂ from the subscriber telephone Tb is added by an addition circuit.
Enter 31.

On the other hand, the digitally encoded voice signal from the conference telephone terminal device CT ₂₃ of the subscriber telephone Tc is input to the incoming line of the B ₂ channel.

In this case, since the conference telephone connection is used and the data terminal DT is not used, the selector 34 is connected to the adding circuit 32 by the control signal from the line control device, and the gate 33 is in the conductive state.

Therefore, the digitized voice signal (A) which is an input to the incoming line of the B ₁ channel is given to the adding circuits 30 and 32,
Further, the adder circuit 32 is connected to the transmission line of the B ₂ channel via the selector.

Therefore, in the adder circuit 30, the signal (A) and the input signal from the incoming line of the B ₂ channel via the gate 33 are added and given to the codec C ₂ , decoded and given to the subscriber telephone set Tb.

Further, the adder circuit 31 adds the digitally encoded voice signal (B) and the input signal from the incoming line of the B ₂ channel through the gate 33, and sends it to the conference telephone terminal device CT ₂₁ .

On the other hand, in the adder circuit 32, the signals (A) and (B) are added and sent to the conference telephone terminal device CT ₂₃ via the selector 34 and the B ₂ channel transmission line.

Thus, in the conference telephone terminal device, the signal from the subscriber's own telephone is added to the adjacent conference telephone terminal device in the conference telephone connection and the signal from the other adjacent conference telephone terminal device in the conference telephone connection is added. Then, the signal from the subscriber's own telephone set and the signal from the adjacent conference telephone terminal device are added and transmitted to the other adjacent conference telephone terminal device.

In the example shown in FIG. 2, in addition to the subscriber telephone set Tb, Tc and Td are further connected. The conference telephone terminal device CT _{23 of the} subscriber telephone set Tc receives the voice signal C of its own as the conference telephone terminal device CT. _Since the voice signal D from ₂₄ is added, the signal (c + d) is input to the incoming line of the B ₂ channel in FIG.

Therefore, in the adder circuit 30, the (A + C + D) signal is given to the subscriber telephone set Tb, in the adder circuit 31, the (B + C + D) signal is sent to the conference telephone terminal device CT ₂₁ , and as described above, the adder circuit 32 adds the signals. Signal (A + B) is sent to the conference telephone terminal device CT ₂₃ via the B ₂ channel transmission line.

That is, by simply connecting the conference telephone terminal devices DT _{21 to} DT ₂₄ to the end of each subscriber's codec C _{1 to} C ₄ and connecting to the digital transmission line, each subscriber telephone Ta to Td can be subscribed to by other subscribers. A voice signal from the person's telephone can be input to make a conference call.

This is because even if the number of subscriber telephones participating in the conference call increases, it is only necessary to provide the conference call terminal device in front of the codec, and the configuration of the conference call terminal device is simple, and the connection control of the digital network is also possible. , Only the connection control part to the increased subscriber telephones is added, and no change is required for connection control in the digital network even if the number of participants increases or decreases during the conference telephone connection.

〔The invention's effect〕

As described in detail above, according to the present invention, there is an effect that it is not necessary to use a particularly complicated device even if the number of subscribers participating in the conference call increases.

[Brief description of drawings]

FIG. 1 is a block diagram of a conference telephone terminal device according to an embodiment of the present invention, FIG. 2 is a block diagram of a communication system including the conference telephone terminal device of an embodiment of the present invention, and FIG. 3 is a conventional conference telephone system. It is a block diagram of. In the figure, C _{1 to} C ₄ are codecs, 10 is a conference telephone device, CT _{21 to} CT ₂₄ are conference telephone terminal devices, 30 to 32 are addition circuits, 33 is a gate, and 34 is a gate.
Is a selector, 35 is a data terminal, 100 and 101 are digital networks, and Ta, Tb, Tc, and Td are subscriber telephones.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Okuyama 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited (56) References JP-A-59-264 (JP, A) JP-A-56-14795 (JP, A) JP 60-232761 (JP, A) Actually developed 59-154959 (JP, U)

Claims (1)

[Claims] 1. A subscriber telephone is connected to a conference telephone terminal device via a codec, and the conference telephone terminal device has an incoming line and an outgoing line, respectively.
Conference telephone connection in a configuration that can be connected to a digital transmission line through the B ₁ channel and B ₂ channel, and a connection between subscriber telephones including a conference telephone connection is formed by a digital network to which the digital transmission line is connected. In this case, the B ₁ channel of the conference telephone terminal device is the conference telephone terminal device of the adjacent subscriber telephone in the conference telephone connection, and the B ₂ channel is the conference telephone terminal of the other adjacent subscriber telephone in the conference telephone connection. An adder circuit that is connected to each device and adds the incoming call to that line to the incoming line of B ₁ channel and the incoming line of B ₂ channel and sends it to the codec,
Also the outgoing line is provided adding circuit for adding and outputting the incoming output and B ₂ channel incoming line self codec, B ₂ channel incoming line adjacent other subscribers telephone conference call of the the A signal from the terminal device is received and B ₁ , B ₂
A conference call is provided between the channels, and the addition circuit adds the output of its own codec and the incoming call to the incoming line of B ₁ channel and outputs it to the outgoing line of B ₂ channel. A communication system including a terminal device.