JPH0327660A - Communication system for plural non-telephone terminals by public telephone network - Google Patents

Abstract

PURPOSE:To select a terminal equipment called by a management center and to connect the line by sending a ball signal with an optional length to a subscriber while a management center varies the time of line interruption and allowing the subscriber to measure the length of a bell ring period of a call signal. CONSTITUTION:A management center 1 receives a call tone from a public telephone network 2 from a network controller NCU 18 and the part is sent to a number detection circuit 17. Upon the receipt of the initial call tone, the circuit 17 starts a timer circuit 14 to start the count of received number of the call tone signals. Since the circuit 17 receives a time Tn corresponding to the terminal equipment from the NCU 18, when the measured time is coincident with the time Tn, it is informed to the NCU 18. The circuit 14 measures the elapsed time by the circuit 17 and when a prescribed time To elapses, it is informed to the NCU 18 via the circuit 17. The NCU 18 starts an automatic dial circuit 16 based on this notice to generate the telephone number of the subscriber again and it is sent to a network 2 to connect the line.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a communication method when a management center communicates with a plurality of non-telephone terminals installed at users' homes using the public telephone network. It is.

(Prior Art) In recent years, a system has been developed in which non-telephone terminals installed in each home are collectively managed by a management center via a public telephone network. One example is a system that automatically measures the usage of gas, water, electricity, etc. installed in each home using the public telephone network.

Figure 2 is a block diagram showing the configuration of such a system ("No-ringing communication service interface (multiple ringing signal type)" published by the Telecommunications Association of Japan, October 15, 1986). The center calls the target terminal at any time via the public telephone network and collects data. In FIG. 2, 8 is a public telephone network, 9 is a telephone, 10 is a management center, 8a is a local exchange on the calling side, 8b is a local exchange on the terminating side, 11 is a terminal adapter, 12 is a meter reading terminal, and 13 is a local exchange on the receiving side. This is a no-ringing trunk provided in the local exchange 8b on the receiving side. The local exchanges 8m and 8b are part of the public telephone network 8.

The above-mentioned no-ringing trunk 13 is specially installed in the local exchange 8b on the receiving side to call the meter-reading terminal 12, and when the control center 10 calls and specifies the meter-reading terminal 12, the no-ringing trunk 13 sends a calling signal of a specific frequency. The terminal adapter 11 receives this, identifies that the call is to the meter reading terminal 12, and connects the telephone line to the meter reading terminal 12.

(Problems to be Solved by the Invention) However, in the above system, it is necessary to provide a special no-ringing trunk in the exchange on the receiving side, which makes the exchange expensive. Particularly when the number of non-telephone terminals installed is small, there is a problem in that installing a no-ringing trunk for an exchange increases the cost burden.

For this reason, it has been difficult to popularize the management of non-telephone terminals by a management center.

An object of the present invention is to provide a communication method that allows communication between a management center and a plurality of non-telephone terminals installed on the subscriber side without providing a special no-ringing trunk in the receiving side exchange.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a management center connected to a public telephone network and a plurality of non-telephone terminals owned by subscribers connected to the public telephone network. In the communication system for communication between the subscriber and the subscriber, the management center disconnects the line once a predetermined period of time shorter than the bell ringing period has elapsed after starting to receive the ring tone in response to the transmission of the subscriber's telephone number, and When a certain period of time has elapsed since the start of reception, the telephone number is transmitted again, and the subscriber measures the first ringing period of the ringing signal that the subscriber receives, and when the same period of time as the certain period of time has elapsed since the start of measurement. When a call signal is received again at some point, the non-telephone terminal corresponding to the measured value is selected and connected to the line.

(Function) If the management center disconnects the line while receiving the ring tone,
A paging signal shorter than the normal bell ringing period is sent from the public telephone network to the subscriber side. That is, the management center can send a paging signal of virtually any length to the subscriber by varying the timing of line disconnection.

Therefore, by allocating the above-mentioned length to each terminal of the subscriber in advance, the subscriber side can perform management by measuring the length of the bell ringing period of the paging signal sent from the management center. Select the terminal that the center is calling,
Can be connected to the line.

(Embodiment) FIG. 1 is a block diagram showing the configuration of a system according to an embodiment of the present invention, in which 1 is a management center, 2 is a public telephone network,
3 is a terminal adapter installed in the home of a subscriber who is a user of the management center J; 4 is a telephone connected to the terminal adapter 3; 5 to 7 are meter reading terminals connected to the terminal adapter 3; A management center 1 and a terminal adapter 3, which are non-telephone terminals such as facsimile and data terminals, are each connected to the public telephone network.

3 is a block diagram of an embodiment of the management center 1 shown in FIG. 1, FIG. 4 is a block diagram of an embodiment of the terminal adapter shown in FIG. 1, and FIG. 5 explains the operation of this embodiment. FIG.

The operation of this embodiment will be explained below based on FIGS. 1 and 3 to 5.

When the management terminal 1 communicates with the subscriber's terminals 5 to 7,
First, the network control unit (hereinafter referred to as NCU) 18 activates the automatic dialing circuit 16 to generate the subscriber's telephone number and sends it to the public telephone network 2. Naka, here N
It is assumed that the CU 1 g has a function of controlling other circuits within the management center 1 in addition to the normal network control function.

The public telephone network 2 checks whether the corresponding subscriber is free based on the telephone number, and if the subscriber is free, it sends a calling signal to the subscriber side and a ringing tone to the management center 1 side.

The management center 1 sets the ring tone from the public telephone network 2 to N.
The CU 1g receives the signal and sends a part of it to the time detection circuit 17. This ringing tone is usually shown in Figure 5 (4).
It is an intermittent sound of 400 Hz as shown in FIG. 2, in which time T4 (about 1 second) corresponds to the ringing of the bell, and time T5 (about 2 seconds) corresponds to the stop of the bell sound. When the time detection circuit 17 receives the first ringing tone (time t in FIG. 5), it activates the timer circuit 14 and starts measuring the elapsed time from the time t.

The time detection circuit 17 detects the time T from the NCU 1B.
Since the time Tn corresponding to the terminal to be communicated with is specified, which is within a shorter range than 4, when the measured time matches the time Tn, the NCU
Notify J&. As soon as the NCU IB receives this notification, it stops calling the subscriber and the line is restored.

On the other hand, the timer circuit 14 measures the elapsed time after being activated by the time detection circuit 17, and when a certain time T0, which is longer than the time T4, has elapsed, the timer circuit 14 sends a message to that effect via the time detection circuit 17. Notify NCU 1B.

NCU 1 8 automatically dials circuit 1 based on the notification.
6 to generate the subscriber's telephone number again, and send this to the public telephone network 2 to establish a line connection.

By the way, for the period T, a different value n is given to each terminal and the button is pressed. Assigned. Therefore, for example, when communicating with terminal 5, the line is disconnected after a period T after the ring tone arrives as shown in FIG. 5(1), and when communicating with terminal 6, the line is disconnected as shown in FIG. As shown in 2), the line is disconnected after the period T2, and the time at which the line is disconnected differs for each communication partner terminal. Accordingly, the public telephone network 2 sends a calling signal corresponding to any one of (1) to (4) in FIG. 5 to the subscriber depending on the terminal of the other party.

Among them, the period T4 assigned to the telephone 4 is one other period T that is the same as the period of the ringing part of the ringing tone,
-T3 are all set to be shorter than period T4.

On the other hand, on the subscriber side, in response to the operation of the management center mentioned above,
Perform the operations described below.

When the management center communicates with the subscriber's terminal, as described above, a ring signal corresponding to the ring tone shown in FIG. 5 is sent to the subscriber from the public telephone network 2 (hereinafter, the subscriber's In the explanation, for convenience, it is assumed that FIG. 5 shows a calling signal). Said paging signal is received by NCU J 9 and a part of it is sent to time detection circuit 20 .

When the time detection circuit 20 receives the calling signal, it activates the timer circuit 21 and measures the duration of the calling signal. This measured value should correspond to one of the periods T, , T2, T3, and T4 assigned to each terminal.

The timer circuit 21 measures the elapsed time after being activated by the time detection circuit 20, and when the measured value matches time T, it notifies the time detection circuit 20 of this fact. Naka, this time T. Pa management center 1
The value is set to be the same as the fixed time T0 measured by the timer circuit 14. After receiving this notification, when the time detection circuit 20 receives the calling signal again within a predetermined time,
The management center 1 determines that the subscriber's terminal is calling, and controls the line selection circuit 22 to call the terminal 5 when the period of the calling signal measured is T, and to call the terminal 6 when the period is T2. , at T3, the terminal 7 is selected, and at T4, the telephone 4 is selected and connected to the NCU 19, and the terminal is notified that the management terminal 1 is calling.

Thereafter, communication is performed with the management center 1 in response to the terminal's response.

When the telephone 4 is selected, a ringing signal is sent and the bell rings only after the telephone 4 is connected to the line by controlling the line selection circuit 22. In this sense, no-ringing switching is being performed. Also, when a normal telephone call is received, the ringing signal remains for the specified period of time T.

If this continues, the telephone 22 will be selected.

(Effects of the Invention) As described above in detail, according to the present invention, there is no need to provide a no-ringing trunk in the receiving exchange of the public telephone network, and there is no need to make any modifications to the public telephone network. The system can be configured without being restricted by the functions of the public telephone network.

Furthermore, since a plurality of terminals can be connected to one telephone line and these terminals can be automatically switched, the telephone line can be used effectively.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a system according to an embodiment of the present invention;
Fig. 2 is a block diagram of a conventional system, Fig. 3 is a block diagram of an embodiment of a management center, Fig. 4 is a block diagram of an embodiment of a terminal adapter, and Fig. 5 is a block diagram of an embodiment of the system shown in Fig. 1. It is an operation explanatory diagram. DESCRIPTION OF SYMBOLS 1... Management center, 2... Public telephone network, 3... Terminal adapter, 4... Telephone, 5-7... Terminal. Fig. 3 A block diagram of an embodiment of the management center Fig. 4 A block diagram of a system according to an embodiment of the present invention Fig. 1 A system diagram of a conventional example Figure 5 is an explanatory diagram of the operation of the system shown in Figure 1.

Claims (1)

[Scope of Claims] A communication system between a management center connected to a public telephone network and a plurality of non-telephone terminals owned by subscribers connected to the public telephone network, wherein the management center connects to the subscriber's telephone When a predetermined time period shorter than the bell ringing period has elapsed since the start of receiving a ring tone in response to the number transmission, the line is temporarily disconnected, and when a certain period of time has elapsed from the start of receiving the ring tone, the telephone number is sent again; The subscriber measures the first ringing period of the received paging signal, and when the subscriber receives the paging signal again after the same period of time has elapsed from the start of measurement, the subscriber measures the period corresponding to the measured value. A communication system for multiple non-telephone terminals over the public telephone network, characterized by selecting a non-telephone terminal and connecting it to a line.