JP3247220B2 - Communication control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication control apparatus for performing a large amount of communication via a digital line between a telephone which performs communication by analog data and a terminal device comprising a facsimile apparatus.

[0002]

2. Description of the Related Art In recent years, communication has been performed via digital lines in communication terminal devices such as personal computers. The digital line uses a method of time-division multiplexing a plurality of communications. In addition, a system has been developed in which telephone signals are digitally encoded, then time-division multiplexed and transmitted, so that telephones communicate with each other. In this system, a telephone signal transmitted from a telephone device through an analog line is used to make a call through a digital line via an adapter. The adapters are provided at both ends of the digital line, convert the telephone signal into digital data, and further convert the digital signal. The digital data is time-division multiplexed and transmitted on one digital line for a plurality of calls, and the receiving adapter performs a process of converting the digital data into a telephone signal.

Japanese Patent Application Laid-Open No. 61-1557099 discloses a technique for distinguishing between a digitized voice signal and a digitized call control signal of a telephone signal when communicating by time-division multiplexing a telephone signal. I have. The telephone control signal includes a signal indicating transmission, response, and disconnection, and since the procedure of the transmission and response signal is defined in advance as a rule between transmission and reception, it can be easily determined that the signal is a communication control signal. It is difficult to determine the subsequent cutting signal. Therefore, a signal composed of a predetermined digital coded sequence that is unlikely to be generated as a digital coded sequence of the audio signal is inserted as the cut signal.

A multiplex time division communication system has been developed by connecting a digital line between a telephone and a terminal comprising a facsimile machine. This is to connect a G3 facsimile apparatus to the adapter and realize facsimile communication via a digital line by the G3 facsimile apparatus.
Facsimile communication uses telephone signals until both the calling and called facsimile devices are connected.After the connection, a facsimile control signal indicating the start of facsimile communication is transmitted and confirmed between the two devices. Is started. For this reason, it is necessary for the adapter to detect in advance that facsimile communication is started from the calling side or the called side, and switch to facsimile communication processing.

There are a plurality of facsimile control signals indicating the start of facsimile communication. That is, when the calling side sends out CNG (representing the non-voice terminal of the calling side),
There is a case where an ED (called terminal identification signal) is transmitted, and a case where a DIS (digital identification signal) is transmitted from the called side. Since these facsimile control signals have different programs for facsimile procedures after receiving these signals, the CNG is not transmitted by the partner adapter even though the calling facsimile apparatus does not transmit CNG.
When the program of the facsimile procedure after CNG is executed inside the adapter as a detection of the error, the procedure executed in the adapter and the procedure executed in the facsimile apparatus connected to the adapter are executed. A gap may occur, and the line may be disconnected.

[0006]

As described above, there are a plurality of types of facsimile control signals indicating the start of facsimile communication, and these must be accurately recognized. Is complicated. The technique disclosed in Japanese Patent Application Laid-Open No. 61-155709 is for discriminating between a voice signal and a disconnection signal, and is not for discriminating a plurality of control signals, and thus cannot be applied as it is.

The present invention has been made in view of the above-mentioned problems, and has as its object to provide a communication control device capable of relatively easily identifying a plurality of facsimile control signals from telephone signals.

[0008]

In order to achieve the above object, a facsimile signal transmitted from a facsimile apparatus via a private branch exchange is converted into communication data used for data communication, and a private branch exchange. Telephone signal encoding means for converting a telephone signal transmitted from the telephone into communication data, switching means for switching between the output of the telephone signal encoding means and the output of the conversion means and connecting to the data communication line, Upon receiving the facsimile control signal representing the facsimile communication start from the facsimile apparatus, the signal corresponding to the kind of the facsimile control signal at the converting means
And control means for converting the sequence into a signal sequence that is continuous for a predetermined number of times and outputting the signal sequence to the data communication line from the switching means.

Further, telephone signal decoding means for decoding communication data from a data communication line into a telephone signal, conversion means for converting communication data from the data communication line into a facsimile signal, output of the conversion means and the telephone signal A switching means for switching the output of the decoding means to output the signal to the private branch exchange; and a signal train corresponding to the type of facsimile control signal indicating the start of facsimile communication from the data communication line.
The signal at the converting means and receiving the number consecutive signal sequence
Control means for converting the signal into a facsimile control signal corresponding to the column and outputting the output from the switching means.

[0010]

A telephone and a facsimile apparatus are connected to the private branch exchange, and the facsimile apparatus also has a telephone function. The facsimile apparatus makes a line connection with the other party through a data communication line by telephone communication. After the connection, when a facsimile control signal indicating the start of facsimile communication is transmitted from the facsimile apparatus, the control unit recognizes this signal, and the conversion means according to the type of the facsimile control signal, a signal sequence that is unlikely to occur in a telephone signal , Specifically, the facsimile control
The signal sequence corresponding to the type of signal is converted into a signal sequence that is repeated a predetermined number of times , and the switching means is switched to output the output of the conversion means to the data communication line. As a result, a facsimile-specific signal corresponding to the type of the facsimile control signal is output separately from the telephone signal.

On the receiving side, a signal sequence distinguished from a telephone signal according to the type of facsimile control signal from the data communication line, specifically, according to the type of facsimile control signal
When a signal sequence in which the transmitted signal sequence has been transmitted a predetermined number of times is transmitted, the control unit recognizes this signal sequence, converts this signal sequence into a facsimile control signal by the conversion means, and switches its output by switching the switching means. Output to the exchanger. As a result, a facsimile control signal corresponding to the type is transmitted to the facsimile apparatus connected to the facsimile apparatus on the transmission side, and facsimile communication is started.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. The communication control device 1 is connected to a private branch exchange 2 having a telephone 3 and a G3 facsimile device 4 as terminals, and performs high-speed digital communication with the communication control device 1 on the other side connected via a digital line 5. The communication control device 1 is provided with a codec 10 that converts a telephone signal and a facsimile signal composed of analog data into digital signals for the digital line 5 and also performs the reverse conversion. The codec 10 is a telephone signal encoding unit 11 for converting a telephone signal input from the private branch exchange 2 into a digital signal.
A facsimile adapter 12 that converts a facsimile signal input from the private branch exchange 2 into a digital signal and converts a digital signal input from the digital line 5 into a facsimile signal, and converts a digital signal input from the digital line 5 into a telephone signal. Telephone signal decoding unit 13
A first switch 14 for switching between the output of the telephone signal encoding unit 11 and the output of the facsimile adapter 12 and outputting to the digital line 5 and switching between the output of the facsimile adapter 12 and the output of the telephone signal decoding unit 13 for private branch exchange. Vessel 2
To the first switch 14,
The switching instruction of the second switching unit 15 is transmitted to the facsimile adapter 1.
2 is performed by the control unit.

FIG. 2 is a hardware configuration diagram of the facsimile adapter 12. The facsimile adapter 12 includes a CPU 21, a ROM 22, a RAM 23, a digital interface 24, a bus 25 connecting these, and a CPU 21.
It is composed of amplifiers 26 and 27 for input and output to the device. CP
U21 converts the facsimile signal input from the private branch exchange 2 into a digital signal and outputs the digital signal from the digital interface 24, and converts the digital signal input from the digital line 5 through the digital interface 24 into a facsimile signal and converts it into an amplifier 27. To the private branch exchange 2 via When a facsimile control signal indicating the start of facsimile communication is transmitted from the facsimile apparatus 4 as a facsimile signal, the facsimile apparatus 4 recognizes this and converts it into a specific signal corresponding to the type of facsimile control signal described later. The signal is switched to the facsimile adapter 12 and output to the digital line 5. When a specific signal corresponding to the type of the facsimile control signal is input from the digital line 5, it is recognized and converted into a facsimile control signal corresponding to the type, and the second switch 15 is switched to the facsimile adapter 12 side. To the private branch exchange 2.

FIG. 3 shows a control code string corresponding to the facsimile control signal, and includes three of the facsimile control signals CNG, CED, and DIS indicating the start of facsimile transmission.
And four types of signals that indicate affirmative to these signals. a is a signal representing CNG, SY on both sides
N is a synchronization code, and FAX inside is an ASCII character. When the facsimile adapter 12 detects CNG from the facsimile machine on the calling side, this is a switching instruction signal for facsimile communication sent to the facsimile adapter 2 of the facsimile apparatus on the called side. If the code string shown in a is continued eight times or more, the code string hardly occurs in the telephone signal. Therefore, in consideration of a transmission error or a reception error, the transmitting side continuously transmits the code string a for 24 times, and is valid when the facsimile adapter 12 on the receiving side detects eight consecutive times. In addition,
The number of continuous transmissions may be 8 × 2 + 1 or more when eight receptions are valid.

The configurations of b, c, and d are the same as those of a.
Each character is a unique character. The number of continuous transmissions and the number of valid receptions are the same as in the case of a. Reference numeral b denotes a CED, which is a switching request signal transmitted to the calling side facsimile adapter 12 when the facsimile adapter 12 detects the CED from the called side facsimile apparatus.
Reference numeral c denotes a switching request output to be transmitted to the calling side facsimile adapter 12 when the facsimile adapter 12 detects DIS from the called side facsimile apparatus. d is an acknowledgment signal transmitted from the facsimile adapter 12 which has received the switching instruction of a and the switching request of b and c to the facsimile adapter 12 which has issued the instruction and request.

Next, an example of a procedure for switching from telephone communication to facsimile communication will be described. FIG. 4 shows the operation when the facsimile adapter 12 detects CNG. When the calling facsimile machine and the called facsimile machine are connected by telephone communication, a CNG signal is sent from the calling facsimile machine 4 and sent to the facsimile adapter 12 via the private branch exchange 2. The facsimile adapter 12 sends the signal shown in FIG.
The facsimile adapter 12 that has received this signal for eight or more consecutive times understands that it is a CNG signal, converts it into a CNG signal, sends it out to the called-side facsimile apparatus 4 via the private branch exchange 2, and outputs d in FIG. 24 acknowledgments shown in
The data is transmitted to the facsimile adapter 12 of the facsimile machine 4 on the calling side using the continuous transmission digital line 5, and the switching is completed when the receiving side detects this for eight consecutive times.

FIG. 5 shows that the called facsimile apparatus is CED.
Is a diagram showing a procedure for switching from telephone communication to facsimile communication when is transmitted. Incoming facsimile machine 4
Facsimile adapter 1
2 transmits the signal shown in FIG. When the facsimile adapter 12 on the calling side receives eight or more of these signals, it converts the signals into a CED signal and sends it to the calling facsimile machine 4, and sends and transmits a positive signal shown in FIG. The call is transmitted to the facsimile adapter 12 on the calling side, and the switching from the telephone communication to the facsimile communication is completed.
The case of the DIS signal is the same as the case of the CED signal.

As a result, different facsimile communication start signals are identified from the telephone signal and recognized by the partner facsimile adapter 12, and the telephone communication is reliably switched to the facsimile communication.

[0020]

As is apparent from the above description, according to the present invention, a plurality of types of control signals indicating the start of facsimile communication are transmitted in a signal sequence that is unlikely to occur in a telephone signal corresponding to the type, and are transmitted. The control procedure, control contents, and configuration of the device for identifying the signal from the telephone signal are simplified, and the control signal can be reliably recognized on the receiving side, and the switching from the telephone communication to the facsimile communication is reliably performed. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment.

FIG. 2 is a hardware configuration diagram of a facsimile adapter.

FIG. 3 is a diagram showing a facsimile control signal indicating the start of facsimile communication.

FIG. 4 is a diagram showing a procedure for switching to facsimile communication when a CNG signal is detected.

FIG. 5 is a diagram showing a procedure for switching to facsimile communication when a CED signal is detected.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Communication control apparatus 2 Private branch exchange 3 Telephone 4 Facsimile apparatus 5 Digital line 10 Codec 11 Telephone signal encoder 12 Facsimile adapter 13 Telephone signal decoder 14 First switch 15 Second switch

Continuation of front page (56) References JP-A-5-22462 (JP, A) JP-A-5-14528 (JP, A) JP-A-3-40552 (JP, A) JP-A-1-316056 (JP) JP-A-1-147933 (JP, A) JP-A-63-237624 (JP, A) JP-A-63-26044 (JP, A) JP-A-63-1238 (JP, A) (58) Field surveyed (Int.Cl. ⁷ , DB name) H04M 11/00-11/10 H04N 1/00 102 H04N 1/32

Claims (3)

(57) [Claims] 1. A conversion means for converting a facsimile signal transmitted from a facsimile apparatus into communication data used for data communication, a telephone signal encoding means for converting a telephone signal transmitted from a telephone into communication data, a switching means for connecting to the telephone signal encoding means of the data communication line by switching the output of said converting means and an output, receives the facsimile control signal representing the facsimile communication start from the facsimile apparatus, the facsimile control by said converting means A communication control device, comprising: control means for converting a signal sequence corresponding to a type of signal into a signal sequence that is repeated a predetermined number of times, and outputting the signal sequence to a data communication line from the switching unit. 2. The facsimile machine according to claim 2 , wherein
Signal according to the type of facsimile control signal received from
2. The method according to claim 1, wherein the sequence is continuous at least eight times.
2. The communication control device according to 1. 3. A telephone signal decoding means for decoding communication data from a data communication line into a telephone signal, a conversion means for converting communication data from the data communication line into a facsimile signal, an output of the conversion means and the telephone signal and switching means for switching and outputting an output of the decoding means to the facsimile machine or telephone, Shin according to the type of the facsimile control signal representing the facsimile communication start from the data communication line
Control means for receiving a signal sequence in which the signal sequence is repeated a predetermined number of times, converting the signal sequence into a facsimile control signal corresponding to the signal sequence by the conversion means, and outputting the output from the switching means. Control device.