JPH0720188B2 - Automatic information reception method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to an automatic reception system in which a receiving side receives an information signal sent from a transmitting side via a no ringing line in the presence of a no ringing connection control signal. Information reception method.

<Prior art> Conventionally, as an automatic information receiving method of this kind, various information signals such as voice and data are transmitted from a center having a database to a no ringing line together with a no ringing connection control signal (hereinafter abbreviated as NRTS), and A method is known in which NRTS is attenuated by a filter or the like that cuts the NRTS band of a receiver and only various information signals are extracted and received. This system is also used in a tele-control system for transmitting and receiving data signals such as water, gas and electricity usage measured by terminal equipment and control signals from a central equipment via a no ringing line.

<Problems to be solved by the invention> However, in the above conventional automatic information receiving method, when transmitting various information signals from the center, NRTS is always transmitted at the same time, and since the transmission frequency of NRTS hits the voice band, When a voice signal is transmitted as various information signals, the voice signal is also cut by the filter of the receiver and a drop occurs, and accurate voice information cannot be obtained.

Therefore, an object of the present invention is to transmit various information signals from the transmitting side.
It is an object of the present invention to provide an automatic information receiving method by which a receiving side can obtain accurate voice and data information by receiving without passing through an NRTS filter.

<Means for Solving the Problems> In order to achieve the above object, the automatic information receiving method of the present invention is an automatic information receiving method using a telephone network as a no ringing line. Sends the no-ringing connection control signal,
The no-ringing connection control signal transmission command signal is transmitted during transmission of this no-ringing connection control signal, and the reception side transmits the command reception signal to the transmission side after receiving the above no-ringing connection control signal transmission command signal and the no-ringing connection. After sending the control signal, the sending side, after receiving the command receiving signal, starts sending the voice and data signals to the receiving side instead of the no-ringing connection control signal, and at the receiving side. , A subtraction circuit for subtracting the no-ringing connection control signal generated by itself from the voice and data signals in order to remove the no-ringing connection control signal included as noise in the voice and data signals received at the receiving side. To do.

<Operation> In general, a third party other than the contractor sends a no-ringing connection control signal from the receiving side through another subscriber line to prevent the system from being used illegally, and at the start of communication, the third side other than the contractor sends the no-ringing connection control signal together with the no-ringing connection control signal. The control signal transmission command signal is transmitted to the no ringing line. The receiver is
Receiving the control signal transmission command signal, while sending a command reception signal to the transmission side, and by itself to start the transmission of the no-ringing connection control signal, while maintaining the connection of the no-ringing line, the transmission side, the command reception signal In response, the sending of the no-ringing connection control signal is stopped and the sending of the voice and data signals is started. Here, the voice and data signals received by the receiving side include the no-ringing connection control signal sent by the receiving side, but the receiving side subtracts the no-ringing connection control signal from the received signal by the subtraction circuit, Obtain only voice and data signals. Therefore, even if the voice and data signals are signals in the same band as the no ringing connection control signal, accurate voice and data signals can be obtained.

<Examples> Hereinafter, the present invention will be described in detail with reference to illustrated examples.

FIG. 1 shows a receiver 11 adopting the automatic information receiving system of the present invention.
FIG. 1 is a block diagram showing an embodiment of the present invention, 1 is a subtraction circuit for subtracting a signal sent from a center (not shown) via a no ringing line 2, 3 is a receiving unit for receiving the signal sent, Reference numeral 4 is a relay for switching and connecting the input side of the receiving section 3 to the no ringing line 2 and the output side of the subtraction circuit 1, and 5 is the subtraction circuit 1 and the no ringing line 2
No ringing connection control signal (NRTS) to NRTS
A sending unit, 6 is a sending unit for outputting a response signal and a command receiving signal described later to the no ringing line 2, and 7 is the subtraction circuit 1
The recording section 8 for recording only the audio signal of the output of the above into a cassette tape or the like controls the blocks 3 to 7 based on the received signal passing through the receiving section 3 and stores the data signal from the subtraction circuit 1 in the storage section 9 Is a control unit that stores the data in the output unit and outputs the output to the output unit 10.

The control unit 8 receives the NRTS input from the center through the no-ringing line 2, the b contact 4b of the relay 4 and the receiving unit 3 at the start of communication, causes the transmitting unit 6 to output a response signal, and is included in the NRTS. In response to the NRTS sending command, the relay 4 is switched and connected to the a contact 4a side, the NRTS sending unit 5 starts sending the NRTS, and the sending unit 6 outputs the command receiving signal. Next, when the center starts transmitting voice and data signals in place of NRTS by this command reception signal, the control section 8 causes the recording section 7 to record the voice signal from which the NRTS has been subtracted by the subtraction circuit 1, The data signal from which NRTS has been subtracted is stored in the storage unit 9 via the relay 4 and the receiving unit 3, and is output to the output unit 10. Furthermore, it is input from the center at the end of communication.
In response to the NRTS stop command, the relay 4 is switched and connected to the b contact 4b side, the NRTS sending unit 5 stops the sending of the NRTS, and the sending unit 6 outputs a command receiving signal for restarting the sending of the NRTS by the center.

An automatic information receiving system by the receiver having the above configuration will be described below with reference to the time chart of FIG.

First, the center performs a no-ringing connection operation 21 with a switch and a no-ringing trunk (not shown) in order to use the no-ringing line 2, and then starts sending NRTS 22 to the no-ringing line 2. The control unit 8 of the receiver 11 receives the NRTS 22 via the relay 4 and the reception unit 3, decodes and discriminates it, and causes the transmission unit 6 to transmit the response signal 23, whereby the set period T ₁ for line use is set. After that, the no-ringing line 2 becomes available.

Next, before the transmission of voice and data signals, the center
When the NRTS transmission command 24 is transmitted in the TS, the control unit 8 of the receiver 11 similarly decodes and discriminates the NRTS transmission command 24, switches and connects the relay 4 to the a-contact 4a side, and the transmission unit 6 After the command reception signal 25 is output to, the NRTS transmitter 5 is made to start transmitting the NRTS 26 after a fixed time. Further, the center receives the command reception signal 25 and at the same time stops the transmission of the NRTS 22, and the connection of the no ringing line 2 is maintained by the NRTS 26 transmitted from the receiver 11. Thus, the reverse rotation preparation period T ₂ of NRTS transmission ends.

When the center starts transmitting the voice / data signal 27 after a certain period of time, the voice / data signal 27 is subtracted from the NRTS from the NRTS transmitter 5 by the subtraction circuit 1 of the receiver 11, so that the receiver 11 receives the no ringing line 2. Since the NRTS included in the voice and data signals received by the receiver 1 as noise due to being transmitted to the receiver 1 is canceled, an accurate signal is obtained, and the voice signal is transmitted to the recording unit 7 and the data signal is transmitted via the relay 4 to the receiving unit. Three
Are output respectively. Then, under the control of the control unit 8, the voice signal is recorded in the recording unit 7, the data signal is stored in the storage unit 9 and is output to the output unit 10. In this way, when the transmission of the voice / data signal 27 from the center ends, the transmission period T ₃ ends. Note that the NRTS included in the voice and data signals received by the receiver 11 as noise is generated from the receiver 11, and the NRTS from the center, like the NRTS of the conventional example,
Since the waveform and phase are not changed by being sent together with the data signal through the line or switch,
NRTS can be canceled accurately and surely.

When the center transmits the NRTS stop command 28 after a certain period of time, the control unit 8 of the receiver 11 which receives the command causes the transmitting unit 6 to output the command reception signal 29, and after a certain period of time, transmits the NRTS to the NRTS transmitting unit 5. To stop. Further, the center receives the command reception signal 29 and at the same time starts transmitting the NRTS 30, and the connection of the no ringing line 2 is maintained by the NRTS 30 transmitted from the center. In this way, the reverse rotation preparation period T ₄ of NRTS transmission ends. Finally, when the transmission of the NRTS 30 from the center is stopped after the lapse of the period T ₅ , the use of the no ringing line 2 ends.

As described above, in the above embodiment, the transmission of the NRTS 22 from the center side is stopped prior to the transmission of the voice / data signal 27, and the NRTS transmission command 24 is output from the center to the receiver 11 via the no-ringing line 2. This command 24 transmits NRTS 26 from the receiver 11 side to maintain line connection, while transmitting voice and data signal 27 from the center side, while receiving to receiver 11
The subtraction circuit 1 for subtracting NRTS from the input signal and the relay 4 for switching and connecting the input side of the receiving section 3 connected to the control section 8 to the no ringing line 2 and the output side of the subtraction circuit 1 are provided.
By switching the relay 4 to the output side of the subtraction circuit 1 by the NRTS transmission command 24, an accurate voice in which NRTS is removed from the input signal,
The data signal is recorded in the recording unit 7, stored in the storage unit 9,
Since the output signal is output to the output unit 10, the NRTS that the receiver 11 itself issues to the voice and data signals received by the receiver 11.
This NRTS can be removed even if the signal contains a noise, and a simple and inexpensive receiver that does not have an expensive filter as in the past can be used to obtain an accurate and complete voice and data signal.

Needless to say, the present invention is not limited to the illustrated embodiment.

<Effects of the Invention> As is clear from the above description, the automatic information receiving system of the present invention is an automatic information receiving system using a telephone network as a no ringing line. The control signal is transmitted, the no-ringing connection control signal transmission command signal is transmitted during transmission of this no-ringing connection control signal, and the receiving side receives the no-ringing connection control signal transmission command signal and then transmits the command receiving signal to the transmitting side. At the same time as sending, the sending of the no-ringing connection control signal is started, and further, after receiving the command reception signal, the sending side starts sending of the voice and data signals to the receiving side instead of the no-ringing connection control signal. At the same time, the subtracting circuit on the receiving side emits itself, which is included as noise in the received voice and data signals. Since the no-ringing connection control signal is removed, it is possible to prevent interference between both signals with a simple and inexpensive receiver that does not have expensive filters and complicated circuits as in the past, and it is possible to obtain accurate signals without loss. Voice and data signals can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a receiver adopting the automatic information receiving system of the present invention, and FIG. 2 is a time chart explaining the automatic information receiving system. 1 ... Subtraction circuit, 2 ... No ringing line, 4 ... Relay, 5 ... NRTS transmission section, 6 ... Transmission section, 7 ... Recording section, 8 ... Control section, 11 ... Receiver, 22, 26,30 …… NRTS,
23 …… Response signal, 24 …… NRTS sending command, 25,29 …… Command receiving signal, 28 …… NRTS stop command.

Claims (1)

[Claims] 1. In an automatic information receiving system using a telephone network as a no-ringing line, a transmitting side sends a no-ringing connection control signal to a receiving side after a no-ringing connection operation, and a no-ringing connection control is performed during the transmission of this no-ringing connection control signal. The signal sending command signal is sent, and the receiving side receives the above-mentioned no-ringing connection control signal sending command signal, then sends the command receiving signal to the sending side, starts sending the no-ringing connection control signal, and further, the sending side After receiving the command reception signal, starts transmitting a voice / data signal to the receiving side in place of the no-ringing connection control signal, and causes the receiving side to transmit the voice / data signal to the receiving side. No ringing connection generated by itself to remove the no ringing connection control signal included as noise in An automatic information receiving system characterized in that a subtraction circuit for subtracting a continuation control signal from the voice and data signals is provided.