JPS585635B2 - Broadcast communication system in time division switch - Google Patents

Description

[Detailed description of the invention] The present invention relates to a broadcast communication system in a time division switch.

An example of a broadcast communication system in which the content transmitted by one subscriber in a group of three or more subscribers is simultaneously received by all the other subscribers in the group is a telephone conference call system.

This conference calling system is easily achieved when using a space division switch by connecting all of the subscribers to be conferenced to a single conference phone trunk, and the conference phone trunk is simply a conference call trunk. Since all that is required is to connect the subscriber's telephone lines, the configuration is extremely simple.

Recently, there has been a demand for broadcast communications similar to conference calls in telex as well.

However, in data communications such as telex, time-division exchange is normally performed, and in this case broadcast communications cannot be implemented as easily as in the case of conference calls.

In the broadcast communication system in a time division switch, all signals sent from each subscriber in a group of subscribers participating in the broadcast communication are sent to a processing unit of the switch, and the processing unit temporarily stores them in a storage device. There is a known method in which a signal is sent to all the subscribers in the group other than the subscriber who sent the signal, and the signal is sent to all the subscribers who should receive the signal. This method has drawbacks such as increasing the load on the processing device and requiring a storage device.

Additionally, a method is known in which signals sent from subscribers are collected within the communication path of the time-division exchange, and from this, signals are created and sent out to be received by other subscribers. Since the signal transmitted from the subscriber is time-divisionally processed and stored in the channel memory, it is necessary to read the memory multiple times, which has the drawback of increasing the processing time for one channel.

The present invention uses a novel broadcast trunk device to perform broadcast communications at the line level in data communications, particularly in time-division switching for telex, which eliminates the drawbacks of the above-mentioned known systems and It is an object of the present invention to provide a broadcast communication system of this type that does not impose an extra load on a device, does not require multiple reading of memory, and has a short processing time for one channel.

Next, the present invention will be explained with reference to the drawings.

FIG. 1 shows a space-divided view of connections for broadcast communications using broadcast trunks.

In FIG. 1a, subscribers A and B are connected to terminals 2-1, 2-2, and 2-3 of one broadcast trunk 2 via the communication path network 1.
, O, and the signal transmitted from subscriber A, for example, is
The broadcast trunk 2 is reached via the network 1 and the terminal 2-1, and the subscribers B and C involved in this broadcast connection via the network 1 from the terminals 2-2 and 2-3.
sent to.

The same applies to signals transmitted from other subscribers B or C.

Here, the broadcast trunk 2 has one terminal (e.g. 2-
The signals input to 1) are configured to be output from all other terminals (2-2 and 2-3).

Figure 1b shows a system in which a plurality of broadcast trunks with a small number of subscriber accommodating terminals are assembled, and at least one terminal of the broadcast trunk is fixedly connected to a terminal of another broadcast trunk. This is a single large broadcast trunk with a large number of terminals for accommodating subscribers, increasing the number of subscribers participating in broadcast communications.

In this case, five subscribers A, B, C, D, E are connected to terminals 2-1 .
2-2, terminal 3-2 of broadcast trunk 3, broadcast trunk 4
is connected to terminals 4-2 and 4-3.

Further, the terminal 2-3 of the broadcast trunk 2 is fixedly connected to the terminal 3-1 of the broadcast trunk 3, and the terminal 3-3 of the broadcast trunk 3 is fixedly connected to the terminal 4-1 of the broadcast trunk 4. A broadcast trunk 5 is configured.

For example, a signal transmitted from subscriber A reaches terminal 2-1 of broadcast trunk 2 via communication path network 1, and this signal is transmitted to subscriber B via terminal 2-2 of broadcast trunk 2. ,
Also, the above signal is transmitted from terminal 2-3 of broadcast trunk 2 to terminal 3.
-1 to the broadcast trunk 3, and to the subscriber C through the terminal 3-2 of this trunk.The above signal then passes from the terminal 3-3 of the broadcast trunk 3 to the terminal 4-1 to the broadcast trunk 4.
and is sent via terminals 4-2 and 4-3 of this trunk to subscribers D and E, respectively.

Figure 1c shows, for example, that when a broadcast trunk with a small number of subscriber accommodating terminals is required for broadcast communication connection by a large number of subscribers, the necessary number of terminals are collected and each broadcast trunk is One terminal is connected to each via a communication path network, and if necessary, a connection corresponding to the large broadcast trunk shown in Figure 1b is made to enable broadcast calls by a large number of subscribers. .

In the case of the figure, a broadcast trunk 2 with three subscriber terminals,
3 and 4, and connect terminal 2-3 of broadcast trunk 2, terminal 3-1 of broadcast trunk 3, terminal 3-3 of broadcast trunk 3, and terminal 4-1 of broadcast trunk 4 to the telephone network. 1, and the subscribers A, B, C, D, and E are connected in the same manner as in FIG. 1b.

The flow of signals transmitted from the subscriber is similar to that in FIG. 1b.

Note that the broadcast trunks 2, 3.4 are capable of independently performing broadcast communication as shown in FIG. 1a.

FIG. 2 is a connection diagram of an example in which the present invention is implemented in a telex, and corresponds to FIG. 1a.

A, B...C are telex terminals, which are accommodated in the time division switch TDS.The transmission line 11 from each terminal reaches the selection circuit 12 which is the signal input section of the time division switch TDS, and the reception line 13 is Similarly, the signal is transmitted from the distribution circuit 14 to each terminal via the signal holding circuit 18.

Signals transmitted from each terminal reach the selection circuit 12 via the transmission line 11, where they are time-division multiplexed and sent to the multiplex line 1.
5. The signal reaches the communication control device 16 via the selection circuit 30, performs an exchange operation such as exchanging time slots, and is sent to the multiplex line 17 as a signal to be received by the terminal.

This multiplexed signal reaches the distribution circuit 14, where it is distributed to each terminal, and reaches each terminal via the signal holding circuit 18 provided for each receiving line and the receiving line 13.

The above operation is similar to the normal time division exchange operation, and 19 is a processing device for controlling the communication control device 16 to set a desired connection based on exchange information or connection information from each terminal.

This embodiment is implemented in telex, and the communication control device 16 is configured to time-division line exchange the telex signals.

That is, the telex signals sent from each terminal A, B, . . . , once the data is stored in the buffer memory, it is then read and transmitted in the time slot assigned to the receiving terminal.

On the multiplex line 17, the signal sent to the receiving side is also added one bit to each time slot assigned to the terminal.

As a result of the above, for example, the signal on the transmission line from terminal A is made to be received by terminal B, and the signal on the transmission line from terminal B is received by terminal A.
It is possible to establish a connection between terminals A and B by setting the connection so that the terminals A and B receive the information.

The selection circuit 12 and the distribution circuit 14 are controlled by a communication control device 16, but their configuration and operation are the same as those of ordinary devices, so a description thereof will be omitted.

In this case, the telex terminal outputs the signal "1" as idle information when there is no communication, and the information is transmitted by the signal "0".
” shall be transmitted by.

Assume now that, for example, three parties, telex terminals A, B, and C, are performing broadcast communication.

In this case, operators are seated at all terminals A, B, and C.
In terms of the procedure, the operator who is transmitting sends a certain code to indicate that the transmission has ended, and the other terminal recognizes this and starts transmitting for the first time, so that two parties can transmit at the same time. prevent doing.

As mentioned above, the signals transmitted from terminals A, B, and C are on line 1.
The signals are time-division multiplexed on the 5th line 5, the time slots are exchanged in the communication control device 16, and the signals are outputted to the line 31.

Further, the communication control device 16 sends a signal 32 to the distribution circuit 21 of the broadcast trunk 20 to designate its output end.

For example, signals from terminals A, B, and C are output to each output terminal α.
, β, and γ.

Here, the output terminals α, β, and γ become the input terminals of the broadcast trunk 20.

These outputs are used as input signals to the broadcast trunk 20 until the next signal arrives at the signal holding circuit 22-α.
, 22-β, 22-γ.

These input signals are logically processed in the logic circuit 23, and from the output line 29 are sent as output signals through the selection circuit 30 and the communication control device 16 in the time slots assigned to the terminals A, B, and C. The signals are added to the divided multiplex line 17 and transmitted to the terminals A, B, and C via the distribution circuit 14 for reception.

Now, the above terminals A, B. It is assumed that the three parties C are in a broadcast communication connection state and that terminal A is transmitting data.

As mentioned above, signals transmitted from terminals A, B, and C are held in the signal holding circuits 22-α, 22-β, and 22-γ, but in this case, the holding circuits 22-α, 22-β, and 22-γ corresponding to terminals B, C −β
, 22-γ, that is, the signals input from terminals B and C are each "1".

In the time slot allocated for reception by terminal A, the communication control device 16 sends a signal specifying the output terminal α'' corresponding to terminal A of the decoder 24, causing the output terminal α'' to output "1". Output terminals β″, γ″ are “0” as usual.
” is output.

These signals are connected to inverting circuits 25-α, 25-β,
Negated by 25-γ and gates 26-α, 26-β
, 26-γ.

Therefore, only the AND gate 26-α becomes non-conductive, its output becomes “0”, and the AND gates 26-β, 26-γ
becomes conductive.

Note that the signals β' and γ' held in the holding circuits 22-β and 22-γ are negated by the negation circuits 27-β and 27-γ, and pass through the AND gates 26-β and 26-γ as they are. , is input to the Noah gate 28.

Therefore, the output of the NOR gate 28 is β'+γ', that is, β'
・γ′, which is sent to terminal A.

In this case, β' and γ' are "1" indicating no signal even if it falls down, so β' and γ' are "1", so terminal A receives a no-communication signal and transmits it by itself. The signal doesn't come back.

Similarly to the above, terminals B and C receive signals α′ and
γ' and α' and β' are received.

In this case, since β′ and γ′ are “1”, α′ is “0”.
"0" or "1" is received depending on whether the signal is "1" or "1".

That is, terminals B and C receive the signal (α'
) is received.

Here, the inputs are applied to the three terminals α, β, γ, and the outputs appear in the three time slots designated by the terminals 7α″, β″, γ″ of the decoder 24.

This means that it has three input ends and three output ends.

Note that it is possible in the logic circuit 23 to increase the input terminals to α, β, γ, δ, etc., and correspondingly increase the output terminals to α″, β″, γ″, δ″, etc. Negation circuit 25-α
, 25-β, 25-γ and 27-α, 27-β, 27
-γ are respectively 25-δ..., 27-δ...and gates 26-α, 26-β, 26-γ are 26-δ...
, and by correspondingly increasing the input fraction of the NOR gate 28, again in this case, for example, β
′+γ′+δ′+...=β′・γ′・δ′・The following relationship holds true, so the desired logical operation is possible and terminal A
The transmitted signal from terminal A does not return to terminal A, but is sent to other terminals B, C,
It is received by D...etc.

Here, the input terminal δ... and the output terminal δ''... correspond to the terminal D...

FIG. 3 shows an embodiment of the invention corresponding to that shown in FIG. 1b.

The numerals in the figure indicate the same ones as in FIG. 2.

The normal 1:1 exchange operation is similar to that shown in FIG.

In this embodiment, the broadcast trunk (CF
T) Use two 20 as components and connect the parts corresponding to one input end and output end to form a large broadcast trunk, and four terminals can participate in broadcast communication. It has been expanded to.

There are now four terminals A, B, C, and D (D is not shown).

) shall perform broadcast communication between the two. At that time, the second
As explained in the figure, under the control of the communication control device 16, signals transmitted from the terminals A, B, C, and D are transmitted from the input terminals α and β of the broadcast trunk 20-1 to the signal holding circuit 22-
1-α, 22-1-β, and signal holding circuits 22-2-β, 22-2 from the input terminals β, γ of the broadcast trunk 20-2.
−γ is assumed to be received and held respectively.

In a certain time slot, under the control of the communication control device 16, the terminal γ'' of the decoder 24-1 is also connected to the decoder 2.
When terminal α'' of 4-2 is designated and its output becomes “1”, AND gates 34-1 and 34-2 become conductive, and as explained with reference to FIG. 2, signal holding circuits 22-1-α,
22-1-β holds “0”, this is sent to the signal holding circuit 35-1 and the signal holding circuit 22-
If "0" is held at the inclination of 2-β and 22-2-γ, this is transferred to the signal holding circuit 35-2 and held.

Assume now that four terminals A, B, C, and D (D is not shown) are performing broadcast communication, and, for example, terminal A is transmitting.

The signal transmitted from terminal A is received and held by the signal holding circuit 22-1-α as described above, and is also transferred to the signal holding circuit 3.
It is also transferred to 5-1 and held there.

When the output terminal α'' of the decoder 24-1 is designated as described above in the time slot allocated for reception by terminal A, the contents of the signal holding circuit 22-1-β (terminal B
The signal received by terminal A is sent based on the contents of the holding circuit 22-1-γ (transmission contents of terminals C and D), but this has nothing to do with the signal transmitted from terminal A. Therefore, the signal transmitted from terminal A will not be returned to terminal A.

When the output terminal β'' of the decoder 24-1 is designated as described above in the time slot allocated for reception by terminal B, the contents of the holding circuit 22-1-α (the contents transmitted from terminal A) and A signal to be received by terminal B is sent based on the contents of the holding circuit 35-2 (transmission contents from terminals C and D), but at this time, since no transmission is being performed from terminals C and D, The signal sent from terminal A is sent to terminal B.
sent and received.

Similarly, terminals C and D receive the signal transmitted from terminal A.

In this way, the signal transmitted from terminal A is transmitted to terminal B,
It is sent to C and D and received, and broadcast communication is performed.

The same applies to the case of transmission from any one of the other terminals B, C, and D.

In this way, by combining multiple broadcast trunks for three terminals each having three input terminals and three output terminals, broadcast communication can be performed for more than three terminals (in the above case, four terminals). Become.

FIG. 4 is a connection diagram of still another embodiment of the present invention, and corresponds to FIG. 1c.

The reference numerals in the figure indicate the same ones as in FIG. 3.

The normal 1:1 exchange operation is similar to that of FIGS. 2 and 3.

In the figure, 20-1 and 20-2 each correspond to broadcast trunks (corresponding to 20 in FIG. 2, and may have the same configuration) that can operate independently.

), in which case it can be a broadcast trunk component.

These can be obtained by independently performing broadcast communication, and in the case of independent operation, the operation is exactly the same as the embodiment shown in FIG.

At that time, one of the output terminals (α'', β'', γ'') of the decoder (not shown) corresponding to 24 in FIG. At the time slot that occurs, the selection circuit 30 enters the communication control unit 16 via the time division multiplex line 15 and sends it out to the desired subscriber terminal.

When performing broadcast communication to, for example, four terminals A, B, C, and D that exceed the capacity of one broadcast trunk (3 terminals), the two broadcast trunks are controlled as components, and, for example, terminal A , B to the input terminals α and β of the broadcast trunk component 20-1, and signals transmitted from the terminals C and D to the input terminal β of the other broadcast trunk component 20-2.
, γ and output from the output line 29-1 of the broadcast trunk component 20-1 in the time slot to which the decoder terminal γ'' of the broadcast trunk component 20-1 is designated. The broadcast signal is routed through the selection circuit 30 and the multiplex line 15 to the input terminal α of the broadcast trunk component 20-2, and in the time slot to which the decoder terminal α″ of the broadcast trunk component 20-2 is designated. The signal outputted from the output line 29-2 of the trunk component 20-2 similarly passes through the selection circuit 30 of the time division switch TDS and the multiplex line 15, and is then sent to the broadcast trunk component 20-1.
is controlled by the communication control device 16 so as to be guided to the input terminal γ.

This state is shown by the dotted line.

Note that the decoder terminal α of the broadcast trunk component 20-1
In a time slot in which decoder terminals β″, β″ or decoder terminals β″, γ″ of the broadcast trunk component 20-2 are specified, the signal output to the output line 29-1 or 29-2 is controlled by the selection circuit 30. It reaches the device 16 and is sent to the required terminal in the same way as before.

As described above, in this embodiment, for example, by connecting two broadcast trunks for three terminals through an exchange, a larger number of broadcast trunks than three terminals are configured, and broadcast communication for four terminals is possible.

Furthermore, it is possible to control a number of broadcast trunks commensurate with the number of subscribers participating in broadcast communication (for example, 3 or more), and the number of terminals participating in broadcast communication can be arbitrarily increased as necessary. It is possible to do so.

Each of the above embodiments is applied to telex, but
This method can be implemented not only in telex but also in other data communications when time division exchange is performed.

Since the present invention is configured as described above, it is possible to perform broadcast communication at the line level in a time division exchange such as a telex, without placing an extra load on the processing device of the time division exchange. Moreover, this type of broadcast communication system is advantageous in that it does not require multiple memory reading and the processing time for one channel is short.

Furthermore, when the number of subscribers participating in broadcast communication increases, it is common to deal with this by increasing the number of terminals on the broadcast trunk. If a broadcast trunk is installed, if there are few participating subscribers, terminals will be wasted and it will be uneconomical, but the present invention, especially the third
According to the embodiments shown in FIGS. and 4, the number of terminals of one broadcast trunk is set to the number of average participating subscribers, and when this number is exceeded, the number of terminals of one broadcast trunk is set to the number of average participating subscribers. By controlling the number of broadcast trunks commensurate with the number of subscribers participating in broadcast communication, it is possible to eliminate restrictions on the number of participating subscribers, reduce the number of vacant terminals, increase the utilization of equipment, and make it economical. There are possible effects.

[Brief explanation of drawings]

Fig. 1 is a space-divided view of connections when performing broadcast communication using a broadcast trunk, Fig. 2 is a connection diagram of one embodiment of the present invention, and Fig. 3 is a diagram of a different embodiment of the present invention. Example connection diagram,
FIG. 4 is a connection diagram of still another embodiment of the present invention. A, B~C~D,E...Terminal, TDS...
...Time division exchange, 11...Transmission line, 12,
30... Selection circuit, 13... Receiving line, 14... Distribution circuit, 15, 17, 31...
...Time multiplex line, 16...Communication control device, 1
8... Signal holding circuit, 19... Processing device, 20.20-1.20-2... Broadcast trunk, 21, 21-1, 21-2. ...Distribution circuit,
22-α to 22-γ, 22-1-α to 22-1-γ, 2
2-2-α to 22-2-γ, 35-1.35-2...
...Signal holding circuit, 23.23-1.23-2...
...Logic circuit, 24, 24-1, 24-2...
- Decoder, 29.29-1.29-2... Output line, 32... Selection line.

Claims (1)

[Scope of Claims] 1. In a time-division switching system that accommodates a plurality of data terminals and includes a communication control device configured to time-divisionally exchange data signals sent and received by each terminal bit by bit, A plurality of time slots of a time-division multiplexed output line are assigned as output terminals corresponding to each input terminal, and data to be transmitted from each of a plurality of data terminals participating in broadcast communication is selectively transmitted. It is configured to send one bit at a time to the input terminal connected to the data terminal, and output data transmitted from other data participating in the broadcast communication one bit at a time from the output terminal corresponding to the input terminal. The transmitter is equipped with a broadcast trunk, and inputs transmission data from a plurality of data terminals participating in broadcast communication to the input terminals respectively assigned to the data terminals of the broadcast trunk, and also inputs the data transmitted from a plurality of data terminals participating in broadcast communication to the input terminals respectively assigned to the data terminals of the broadcast trunk. A broadcast communication system in a time division switch, characterized in that data from an output end corresponding to the input end is controlled so as to reach each data terminal via the communication control device. 2. The broadcast trunk is composed of a plurality of broadcast trunk components, and at least one output end and one input end of the broadcast trunk that constitutes the component are input terminals of other broadcast trunk components. 2. A broadcast communication system in a time division exchange according to claim 1, wherein the broadcast communication system is fixedly connected to the end and the output end, respectively. 3. The above-mentioned broadcast trunk is composed of a plurality of broadcast trunk components each capable of operating as a broadcast trunk, and at least one output end and one input end of the broadcast trunk that are the components are 2. A broadcast communication system in a time division switch according to claim 1, wherein the broadcast communication system is connected to input ends and output ends of other broadcast trunk components via the communication control device, respectively.