JPH021417B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a data transmission system for subscriber telephone lines for transmitting information on automatic meter readings of water, gas, electricity, etc. meters and alarm signals for disaster prevention or crime prevention to the telephone line. In particular, the present invention relates to a data transmission system for a subscriber telephone line that uses the subscriber telephone line to transmit data without interfering with normal call operations.

Recently subscribed telephone lines (hereinafter referred to as "telephone lines")
A system in which a central device collects data from a terminal device located in a remote location using the system, for example, an automatic meter reading system that automatically reads the usage of water, gas, electricity, etc., is being put into practical use.

This type of data collection device uses telephone lines to
Data transmission is performed during times when telephone calls are not being made. Conventional devices for this purpose have a call priority function that does not interfere with calls, a no-ringing connection function that connects the telephone line without ringing the telephone bell during data transmission, and a function that uses less current from the telephone line as an operating power source. It has main functions such as a station power supply function that operates in Further, this type of telemeter device mainly has a terminal call reception function (polling) that activates the terminal device from the center device. In recent years, with the widespread use of telemeter devices, there has been a demand for devices that have not only a terminal call reception function but also a terminal transmission function (calling) for activating a center device from a terminal device. For example, reporting malfunction information for collecting sales volume information in vending machine management equipment, reporting when an abnormality occurs for periodic condition monitoring in equipment management equipment, or automatic meter reading of ordinary household meters in the event of fire or theft. It is expected that it will develop and expand into a variety of uses and services, such as reporting.

However, when adding a terminal calling function to a terminal call receiving (polling) device using a telephone line, consideration must be given to the billing system, as in the case of terminal call receiving. It is also necessary to consider end-to-end signal transmission from the center to the terminals, and it is necessary to consider the distribution of various control signals within the voice band. For this reason, it is desirable to share control signals or to make the sequences the same between terminal incoming calls and terminal outgoing calls.

The present invention has been made against this background, and it is possible to receive calls from a terminal and make calls from a terminal, and furthermore, it is possible to receive calls from a terminal without ringing, and to simplify the equipment by using a common sequence when transmitting and receiving signals. The purpose is to provide an economical remote control method.

The present invention is a data transmission method in which a data transmission terminal and a center-side device that controls the terminal and collects data sent by the terminal are connected via a subscriber telephone line, and the data transmission method is automatically connected to the center-side device. A center network control device including means for transmitting dial information for calling each terminal, means for receiving a call signal transmitted from the terminal, and means for transmitting and receiving control signals and data; The telephone ring of the called subscriber is selectively connected to the switching center that accommodates the telephone line to which the terminal is connected, and the telephone bell of the called subscriber is ringed. The terminal side of the subscriber telephone line to which the above-mentioned terminal is connected is provided with a special trunk including a means for making a call connection without causing any interruption, and a connection means for responding to an incoming call in response to a connection signal sent by the above-mentioned center network control device, and a means for making a call from the above-mentioned terminal. In a data transmission system for a subscriber telephone line to which a terminal network control device is connected, the system includes means for automatically connecting to the center-side device and means for transmitting and receiving data transmission between the center-side device and the center-side device. A call signal sent from the center-side device to the terminal network control device for connection made via a trunk, and a call signal sent from the center-side device to the terminal network control device when the terminal makes a call and connects to the center-side device. When the response signal sent from the terminal to the terminal network control device is the same signal, and the data transmission sequence after the terminal and the center side device are connected is performed in either direction. It is characterized by being configured so that it is common to both.

An embodiment of the present invention will be described based on the drawings.
FIG. 1 is a block diagram of essential parts of an embodiment of the present invention. The central device 1 is connected to a center network control device 3 via a connection line 2. This center network control device 3 is connected to a switching center 5 via a center side telephone line 4. This exchange 5 is connected to an exchange 7 on the terminal side via an inter-office trunk line 6. A special trunk 8 is connected to this exchange 7. The exchange 7 is connected to a terminal network control device 10 via a terminal-side subscriber telephone line 9. This terminal network control device 1
0 is connected to a telephone 11. Further, a terminal device 13 is connected to this terminal network control device 10 via a connection line 12.

Here, the central device 1 is a data processing device (CPU) that controls the center network control device 3. The center network control device 3 has functions for transmitting dial information and various control signals necessary for connecting the special trunk 8 and the terminal network control device 10 when making a call from the center, and a 16Hz ringing function when making a call from a terminal. This device has signal reception functions, various control signal transmission/reception functions, and data communication modulation/demodulation functions. Also,
The special trunk 8 is attached to the switching center 7, and when the center is connected, it becomes the called side for the center side equipment and the calling side for the terminal side equipment, and provides the no-ringing connection function of the terminal network control equipment 10. This is a device that has When the terminal network control device 10 makes a call from the center,
An automatic calling network control function capable of receiving a calling signal when a no-ringing connection command is issued from the center network control device 3 and further transmitting data, and sending out a dialing signal when receiving a calling request signal from the terminal device 13. This device also has an automatic transmission network control function that allows data transmission after the connection with the center side device is completed. The terminal device 13 is a device that has the function of sending information to the terminal network control device 10 and requesting the terminal network control device 10 to make a call when emergency information occurs.

FIG. 2 is a diagram showing an operation sequence when a center call is made in the embodiment shown in FIG. 1, and FIG. 3 is a diagram showing an operation sequence when a terminal call is made in the same embodiment.

The characteristic operation of the present invention will be explained using such a circuit configuration.

First, the operation when making a call from the center will be explained.
The central device 1 issues a command to create the same conditions as when a telephone call is made by starting meter reading (FIG. 2a). The exchange 5 detects this and returns a dial tone (DT) (b in the same figure). The central device 1 transmits a dialing signal for a special trunk 8, and the exchange 5 transmits the dialing signal to the incoming trunk ICT (Incoming Trunk) of the receiving station 7 through an inter-office trunk line 6. 8 is selected and 16Hz
A ringing signal is sent out. When the special trunk 8 returns a response, the exchange 7 notifies the central equipment 1 of the polarity reversal, and the central equipment 1 side is now connected to the special trunk 8. (Figure c to d).

Next, a control signal (A signal) is sent from the central device 1 to the special trunk 8, and the input register of the exchange 7 is sent to the special trunk 8.
It controls the IR (Incoming Register) and notifies the center of its response using the B signal (Fig. 2 e to f).
In this state, the central device 1 responds to the special trunk 8 by
The subscriber number targeted for data transmission is sent out as a second dial signal, and the exchange 7 performs a switching operation based on this signal. After the line is connected between the center side and the terminal side, an activation signal is sent to the terminal network control device 10 by reversing the polarity (g in the figure). At this time, the exchange 7 does not send out a 16Hz bell signal.

Next, the terminal network control device 10 is activated by a paging signal (signal c) sent from the center network control device 3, and the no-ringing connection is completed (FIG. 2h). The terminal network control device 10 returns a response signal (D signal) (i in the figure). In this state, the central device 1 and the terminal device 13 completely enter the data transmission mode.

Data is sent and received using the E signal and F signal (j, k in the same figure) in FIG. 2, and after the data transmission is completed, the central device 1 transmits the special trunk control signal (A signal).
(m), and the exchange 7 releases the terminal network control device 10 (m). As a result, the response signal (D signal) is also disconnected (m in the figure). Furthermore, the central device 1 cancels the call and terminates everything (o in the figure).

In this way, the no-ringing connection according to the present invention is achieved by providing the special trunk 8 and the terminal network control device 10, and by combining the first dial and the second dial. Moreover, the signal A~
F is a signal within the voice band.

Next, the operation when the terminal makes a call will be explained with reference to FIG. The terminal device 13 sends a call request signal to the terminal network control device 10 at an arbitrary time (FIG. 3a'). The terminal network control device 10 monitors the usage status of the telephone line 9, and if it is not in use, closes the DC loop and sends a call acceptance signal to the terminal device 13 (b' in the figure).

Next, when the terminal network control device 10 receives the selected dialing information from the terminal device 13, it sends a dialing signal to the exchange 7. The exchange 7 transmits the dial signal to the opposite exchange 5 via the inter-office trunk line 6. Based on the dial information, the exchange 5 selectively connects the telephone line 4 to which the center device is connected, and sends out a calling signal (16 Hz) (c' in the figure). When the center network control device 3 detects this calling signal, it responds by creating a DC loop. (d' in the same figure) Furthermore, an AC signal (c') is sent out as a center response signal (e' in the same figure).
When the exchange 5 detects a DC loop, it returns a polarity inversion signal to the exchange 7 and connects the line when charging the calling side (terminal), and connects the line to the exchange 5 when charging the called side (center). A toll-free incoming trunk installed on the side prevents this polarity reversal from being returned (d' in the same figure).

The terminal network control device 10 uses this polarity inversion signal and the center response signal (c') at the time of terminal charging.
When it receives the response signal (D′), it sends out the response signal (D
Figure f′). Since there is no polarity reversal signal during center billing, the center response signal (c') becomes the connection confirmation signal, and when this center response signal (c') is received, a response signal (D') is sent back (f in the same figure). '). In this state, the central device 1 and the terminal device 13 are completely in the data transmission mode.

Next, data is transmitted and received using the E' and F' signals shown in FIG. 3 (g and h' in the same figure). After data transmission is complete,
In response to a communication termination command (G') from the central device 1 (i in the figure), the terminal device 13, which is the calling side, restores the calling request signal to the terminal network control device 10 and ends the communication (j' in the figure).

In this way, if we compare the two sequences when calling from the center and when calling from a terminal, we can see that after the line is connected, the signals C and C', D and D', E and E', and F and F' are exactly the same signals. can be used and the same circuit can be used.

As explained above, according to the present invention, it is possible to perform both terminal incoming calls and terminal outgoing calls, and the transmission and reception of signals after the line between the center side and the terminal side have been connected, that is, the ringing signal at the time of no-ringing incoming call. The sequence after the center response signal when the terminal originates is the same.

Therefore, the control procedures for the exchanges can be the same, so the exchange control can be standardized, and the exchange equipment can also be used in common, so the equipment can be configured economically and the entire system can be constructed at low cost. can.

[Brief explanation of drawings]

FIG. 1 is a block diagram of essential parts of an embodiment of the present invention. FIG. 2 is a diagram showing an operation sequence when a call is made from the center in the above embodiment. FIG. 3 is a diagram showing an operation sequence when a terminal makes a call in the above embodiment. DESCRIPTION OF SYMBOLS 1... Central device, 2... Connection line, 3... Center network control device, 4... Center side telephone line, 5... Originating station, 6... Inter-office relay line, 7... Switching station, 8... …
Special trunk, 9...terminal side subscriber telephone line, 10
... terminal network control device, 11 ... telephone, 12 ...
Connection line, 13...Terminal device.

Claims (1)

[Claims] 1. A data transmission system in which a data transmission terminal and a center-side device that controls the terminal and collects data sent by the terminal are connected via a subscriber telephone line, and the center-side device has: A center network control device including means for automatically transmitting dialing information for calling each terminal, means for receiving a calling signal transmitted from the terminal, and means for transmitting and receiving control signals and data, and this center network. A central device that controls the control device is selectively connected to the switching center that accommodates the telephone line to which the terminal is connected, and the telephone ring of the called subscriber is selectively connected based on the dial information sent from the center network control device. A special trunk including a means for making a call connection without ringing is provided, and on the terminal side of the subscriber telephone line to which the above-mentioned terminal is connected, there is provided connection means for responding to a connection signal sent from the above-mentioned center network control device, and from the above-mentioned terminal. In a data transmission system for a subscriber telephone line connected to a terminal network control device including means for making a call and automatically connecting to the center side device, and means for transmitting and receiving data transmission between the center side device, A call signal for activating the terminal network control sent from the center side device to the terminal network control device for connection to be made via the special trunk, and a call signal issued from the terminal to connect to the center side device. is configured such that the response signal sent from the center-side device to the terminal network control device when the above-mentioned center-side device is performed is the same signal, and data transmission after the above-mentioned terminal and the center-side device are connected. 1. A data transmission system for a subscriber telephone line, characterized in that the sequence is the same no matter which direction the sequence is made.