JPS597255B2 - Communication method between multiple subscriber stations - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a plurality of subscriber stations connected in series to form a closed loop line, each subscriber station having a register containing the address of the subscriber station with which it communicates, and at least A digital message containing an address and the information to be transmitted circulates on the ring line, and the subscriber station accepts a message with an address that matches the address stored therein, and the subscriber station receives the message generated by it. Alternatively, the present invention relates to a communication system between a plurality of subscriber stations for transmitting messages containing information to be received.

A message here means communication information including at least one address and information to be transmitted. Ring systems are known in which a connection can be established between two respective parties for the purpose of transmitting messages.

To make such a connection between two counterpart subscribers,
The selection information is stored in the address sending register at the caller's location, and the call message is sent! ! ) Circulate around the circular track.

The called party verifies the unique address in the free D message and then writes the calling party's address to the called party's address receiving register and/or address sending register. The called party responds with a free message, which is received by the calling party and rings on the calling party's handset. When the called party picks up the handset, another message is sent to the calling party, which places the calling party's subscriber console in a talking state. The connection is then terminated and information exchange can begin. In this way only a connection between two subscribers is made.

Since the ring line is not provided with a central switch, it is not possible to provide a central circuit for interconnection or multiplexing between more than two subscribers. The problem of the present invention is to
The object of the present invention is to enable such multiple connections in a ring system without using a central switching device.

Another object of the invention is to provide multiple connections in such a way that all subscriber stations are equal, so that each subscriber equipped with the necessary circuitry can connect new subscribers regardless of the other subscribers. to the connection, and each subscriber can voluntarily leave the call without interfering with the communication of other subscribers.

To solve these problems, the present invention provides that when three or more subscriber stations are interconnected, each subscriber station receives a message from a second subscriber station and sends a message to a third subscriber station. The message information is received by each subscriber station and forwarded to the next subscriber station until the message information returns to the subscriber station from which it originally originated.

Embodiments of the invention are set out below with reference to the drawings.

A communication device having a plurality of subscriber stations connected to form a ring line is shown in Japanese Patent Application Laid-Open No. 49-52907 of the present applicant. Here, each of the plurality of subscriber stations has a receiving register and a transmitting register. Within these registers are the addresses (calling numbers) of the subscriber stations, from which messages are received, and to which messages are sent. Here 2
Since only one subscriber station is interconnected, these two
two addresses are the same. First, it is assumed that a conference call is to be made between subscribers A, B, C, and D connected to ring line 1 without a central exchange.

The arrangement in Figure 1 shows the actual position of the subscribers A-D on the ring line 1, and Figure 2 schematically shows how the subscribers A-D communicate after the call is connected. There is. That is, in FIG. 2, subscriber A receives a message from C and sends it to D. B receives from D and transmits to C. After the connection has been made, the contents of the sending address register T and receiving address register R of the individual subscribers A-D are as shown in FIG. The length of this conference loop is generally larger than the connection loop, and if there are n participants in the conference call Vc, the length of the conference loop will be 1 to n-1 times the length of the connection loop. In FIG. 4, reference numeral 1 indicates a ring line through which digital messages circulate in a counterclockwise direction. Reference numeral 2 indicates a subscriber stand connected to this ring line 1.

One of these subscriber stations is shown in a dashed block. 3 is a monitoring platform inserted into the circular track 1, and is not relevant here.

In the subscriber station 2, 1a is an incoming line and 1b is an outgoing line.

The input V line 1a is connected to the timing circuit 4 and the input end of the reception register 5. This receiving register 5 is a shift register, and is controlled by the 1 timing circuit 4, so that all pulses arriving at the input line 1a are read into this receiving register 5 and shifted at the same timing. Finally, the input wire 1a is connected to an electronic three-position changeover switch 6, which switches the output wire 1b into the first position a, the input wire 1a, and the second position b. The output terminal of the transmitting register 8 is connected to the output terminal of the receiving register 5 at the third position c. The capacities of the receiving register 5 and the transmitting register 8 are the same. Decoder 9 decodes the contents of reception register 5 and provides a signal to control circuit 7 when a predetermined bit combination is detected.

The receiving register 5 and the transmitting register 8 are connected to a relay circuit 10. This relay circuit 10 is an electronic circuit that performs analog-to-digital conversion and digital-to-analog conversion, and connects the telephone 11 to other circuits in the subscriber stand 2, including the reception register 5, transmission register 8, decoder 9, and control circuit 7. Connect to. The relay circuit 10 connects the reception register 5
It receives digital messages from the subscriber and converts them into signals that can be received by the subscriber, i.e., the bell or buzzer signal of the telephone 11 and a call signal, and also converts the signals from the subscriber, i.e., the pick-up signal of the telephone 11, the dialing signal, and The call signal is converted into a digital message and supplied to the transmission register 8. Receiving and sending messages is related to the subscriber's call status.

That is, the call status is stored in the relay circuit 10 each time,
This call status can be changed by a signal coming from the telephone set 11 or the reception register 5. Relay circuit 10
and the functions of the pedestal circuit 7 are temporally related to each other. Reference numeral 22 designates the transmission address register Tl23 and reception address register Rl24, which have already been described, and the additional address register A.

Particularly for calls between only two subscribers, it is possible to use only one of the two registers, but then it is difficult to meet the requirements regarding the confidentiality of the call.

FIG. 5 shows, in the form of a table, the functions of the subscriber station (transmission station) The function of the transmitting subscriber station (receiving station) Y is shown.

Therefore, this figure does not show the call connection process between X and Y. In the first column 1 of FIG. 5, the process of generating a message is shown in six stages.

The second column shows the status of the transmitter X. In other words, in the upper row of the grid frame, there are information about the generation of the message and the sending address register T1 and the receiving address register R}
and the contents J of the additional address register A are shown, and in the lower row, the generation and death of the message and the contents of the address registers T, R, and A after transmission are shown. The third column shows the name and content of the message, which consists of the address of the transmitter X, a signal code and another address. Fourth
The column indicates the state in which the receiver Y has died, and the upper row of the grid frame shows the contents of the address register of the receiver Y before receiving the message. Finally, the fifth column V shows the messages sent from the receiver Y. As can be seen, in some messages the address matches the receiver address, and in others it does not. Z indicates another address. Furthermore, grids with no characters in the second column and fourth column indicate that their contents are meaningless for the process. Next, messages at each stage of the sending and receiving process will be explained. First stage: Call from transmitter X to receiver Y.

When a YO calling subscriber (transmission station X) selects a calling number for the message, the selected calling number Y is sent to the transmission address register T of the transmission station x. A paging message XIY is sent. As shown in the grid frame above the fourth column, reception desk Y is vacant (reception address register R = 0
), the address of the transmitting station X is written to the receiving address register R and the sending address register T when the receiving station Y dies, and the empty message Y2X is returned. If receiver Y is not available as shown in the grid frame at the bottom of the fourth column (
R=Z), nothing is done. When the second stage transmitter X receives an empty message, the relay circuit 10
allows a ringing tone to be heard on the receiver of the transmitter X, and a busy tone to be heard if no response is received.

3rd stage Connection from X to Y.

Message X3Y is generated by picking up the handset. The transmitter X then instructs the receiver Y to store the address X in its reception address register, and if the address previously stored there is not the same as X, sends a connection message Y3Z. command to do so. Here, Z is the address stored in Y's transmission address register. When connecting two subscriber stations, it is Z-X.

In this case, a message sent to the transmitter terminates the ringing. The fourth stage holding message X8 is generated by the electric power train.

As a result of this operation, the contents of the transmitting register are sent to the additional address register A at the transmitting stand X, and the receiving register is erased. Furthermore, a signal message X8 is transmitted. This message means that the receiver Y, which has stored the address grid frame). If it is not R-X, nothing is done (the grid above the fourth column). The fifth stage transfer message XI3Z is generated by the electric current ≠.

This electric wire is used to initiate multiple connections. As a result of this operation on one subscriber station, a signal message is emitted with an address from the additional address register A, which is then set to O.

The message is received by the subscriber station whose receiving address register stores the address of the sending station, and the address from the additional address register of sending station X is written into the sending address register T of receiving station Y. . Furthermore, receiver station Y sends a connection message Y3Z to the subscriber station whose address is stored in the sending address register. 6th
Termination of stage connection.

Message X7Z is generated by hanging up. When the handset is hung up, the receive address register R of the transmitter X is set to O and the message X7Z is transmitted. Here, Z is the address stored in the transmission address register T of the transmission stand X. This message X7Z is received by the subscriber station whose address X is in the sending address register T, and therefore on the ring line by the subscriber station further in the ring. There address X is replaced by address Z and a connection message Y3Z is sent. This table of signaling commands allows arbitrary multiple calls to be made as shown in the following example.

For the sake of simplicity, it is assumed here that the called subscriber is always free. Figure 6 shows an example of conference connection,
The process initiated, the sender and content of the message, the recipient of the message, the hexagram and the registers of each subscriber A-D, namely sending address register T1 receiving address register R
and the contents of additional address register A are shown in the respective columns.

1st stage A call from subscriber B to A.

After caller B dials A's number, B's sending address register T stores this selected address A. A paging message BlA is transmitted, this paging message is received by A, and the address B is written in A's sending address register T and receiving address register R. A responds with a free message A2B, which is received by B and rings (see line 2). When the second stage A picks up the handset, a connect message A3B is sent from A to B, writing the address A into B's receive address register R.

B then sends a connect message B3A, but this message B3A is dead and has no effect. This is because address B is already in A's receive address register. This establishes a connection between A and B. In the third to fifth stages, B allows C to join the call.

The third step B presses the electric key *, which causes the address to be transferred from the sending address register T of B to the additional address register, and at the same time the receiving address register R is set to O.

Then message B8 is sent, and this message B
8 is received by A. This is because A's reception address register R contains address B. This reception address register R is set to O. A sends message A8, which is not received by any subscriber. This is because there is no longer address A in any of the receive address registers. Step 4 Similar to the first and second steps of the process carried out by A, B
Connect with.

After making the connection with the fifth stage C, B presses the telephone line, which causes a message B13A to be sent and received by C).

This is because B is in the reception register of C. C
The address A contained in the message is written to the transmission address register T of the message. C emits a message C3A, which is received by A and the address C is written into A's receive address register R. On the other hand, A
sends a message A3B, which is received by B and address A is written to B's receiving address R. Finally B sends message B3C, which no longer has any effect. This is because B is already in C's receive address register R. A conference connection is now made, in which it receives from AlliC and sends to B, B receives from A and sends to C,
C receives from B and sends to A.

If the subscriber station of each of the three subscribers A-C is equipped with an additional address register and the necessary circuitry for transmitting messages with code numbers 8 and 13, each subscriber has a separate Subscribers can be included in the call.

In steps 6 to 8, A allows the subscriber to join the call.

This process is the same as the third to fifth stages. As a result, the conference call connection shown in FIG. 2 is established. When the ninth stage A hangs up, A's receive address register R is set to O and message A7D is transmitted.

This message is sent by C with A in the send address register.
received by. The transmission address register T of C is
It is replaced with the address D included in the message.
C then sends a message C3D, which is received by D and writes the address C into D's receive address register R. This leaves the Alli ring track. Step 10 C also hangs up and the same process as described for step 9 takes place.

At this time, only B and D remain in the dead call state. For the transmission of information during a call, various possibilities are provided, an example of which is illustrated in FIG.

This figure shows the subscriber console switch circuits; these switch circuits are necessary to transfer conference calls.
This method is based on the fact that only information from each appropriate subscriber to other subscribers is conducted via the ring line. If a subscriber goes dormant, another subscriber can take over the call. This handover takes place according to predetermined volume and time criteria. Now, in FIG. 7, 1a is the incoming line, 1b is the outgoing line, and 116 is a switch that connects the outgoing line 1b to the incoming line 1a or the original transmitting circuit.

By sending and receiving messages, the switch 16 connects only one subscriber station to the sending side and all other subscriber stations to the forwarding side. Connected to the conference ring line. When a subscriber receives a message and sends (forwards) the information contained in this message to the next subscriber, the message sent has a new address.

The circuitry required for this is not shown in the figure. Entry line 1a
A digital-to-analog converter 12 is connected to
1 This converter converts the telephone messages into analog signals which go to the handset 13 and at the same time to the rectifier and low pass filter 14. Speech information arriving on conductor 15 from the handset goes to a rectifier and low pass filter 17. The outputs of both low-pass filters 14, 17 are connected to a comparator 19, which
When the aforementioned volume and time criteria are met, the switch 16 is switched to the transmit side via the switch control circuit 20. Before transmission from the analog-to-digital converter 18,
A message is transmitted by the circuit 21, which switches the hitherto sending subscriber to the receiving side. Each message is transferred from one subscriber to another over the conference line, with the serial address being changed by information arriving over the conference line from the other subscriber, as described above. The message arrives at the subscriber who originated the message and whose switch 16 is on the sending side. this is,
Since only one of the subscribers on the conference line dies, messages arriving at this subscriber must originate from this subscriber itself, and this subscriber does not forward messages. The present invention has the features described in the claims, and the following is an example of the embodiment thereof.

1) Each subscriber station in the conference line 1 is connected to the switching device 1
6, the switching device compares the levels of the incoming call signal and its own call signal with each other, switches the subscriber station from receiving to transmitting according to predetermined time and volume standards, and at the same time switches the subscriber station from receiving to transmitting. When a subscriber dies, a message is transmitted from one subscriber to the next and which switches the subscriber who has been talking from sending to receiving, and therefore within the conference line and from one subscriber to the next. A communication system as claimed in the claims, in which only signals circulated.

2) A subscriber who wants to have another subscriber join the call connection that is being formed writes the address of one of the two subscribers directly connected to this subscriber in the additional address register, and the other subscriber A call between mutually connected subscribers in which the subscriber establishes a connection with the subscriber indicated by the address and informs the other subscriber of the address entered, so that this subscriber establishes a connection with the subscriber indicated by the address. A method as claimed in the claims for conducting a conference call by inviting other subscribers to participate in the conference call.

3) When a subscriber leaves a conference call, this subscriber informs the other subscriber of the address of one of the two directly connected subscribers, and the other subscriber A method as claimed in the claims, in which a direct connection is established with the subscriber indicated by the address given.

[Brief explanation of drawings]

Figure 1 is a diagram showing a ring line with letters attached to four of the subscribers, Figure 2 is a schematic diagram of a conference line in which four subscribers are connected together, and Figure 3 is a diagram of a ring line with letters attached to four of the subscribers. 4 is a schematic block diagram of the subscriber station, and FIG. 5 is a diagram showing the signal messages, message functions, and messages. FIG. 6 is a table showing the contents of the registers of the four subscriber stations when making a conference connection, and FIG. 7 is a block diagram of the subscriber station circuit for making a conference call. DESCRIPTION OF SYMBOLS 1... Ring line, 2... Subscriber stand, 5... Receiving register, 7... Control circuit, 8... Transmitting register, 1
0... Relay circuit, 12... Digital to analog converter, 16... Switch, 18... Analog to digital converter, 22... Transmission address register, 23
...Reception address register, 24...Additional address register.

Claims (1)

[Claims] 1 A plurality of subscriber stations 2 are connected in series to form a closed ring line 1, each subscriber station 2 having a register 22, 23, 24 containing the address of the subscriber station 2 with which it is to communicate; A digital message containing one address and the information to be transmitted circulates on the ring line 1, the subscriber station 2 accepts the message whose address matches the address stored therein, and the subscriber station is thereby generated. If three or more subscriber stations A, B, C, D are interconnected, each subscriber station A, B, C, D is A message is received from two subscriber stations C, D, B, and A and sent to a third subscriber station D, C, A, and B, and the information in the message is transmitted to the subscriber station that originally sent this information. A method of communication between a plurality of subscriber stations, characterized in that the information in this message is received by each subscriber station A, B, C, D and transferred to the next subscriber station until the return to the subscriber station.