JP3128463B2 - Facsimile communication method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to ITU-T Recommendation T30.
The present invention relates to a facsimile communication method that can be used for a facsimile apparatus conforming to the G3 standard, which has been standardized by G3, and particularly to a facsimile communication method in which the communication protocol is speeded up.

[0002]

2. Description of the Related Art A communication protocol in a G3 facsimile apparatus according to ITU-T recommendation T30 is performed according to a signal sequence shown in FIG.

In FIG. 10, each signal indicated by a thin solid line indicates a low-speed signal. This low-speed signal includes TSI and NS as signals from the transmitter side.
There are S, EOP, and DCN, and signals from the receiver side include NSF, CSI, DIS, CFR, and MCF.
TCF and PIX from transmitter side indicated by thick solid line
Is a high-speed signal. CNG from the transmitter side and CED from the receiver side, which are indicated by thin dotted lines, are tone signals.
The dial on the transmitter side is a signal for the line network.

[0004] The transmitter dials the other party in response to a transmission request from the operator. Thereafter, when the line is connected, the tone signal CNG is transmitted.

When the receiver detects an incoming call and connects to the line,
The tone signal CNG from the transmitter is detected. When this is detected, the tone signal CED, the low-speed signals NSF, CS
I, DIS are sent to the transmitter.

The transmitter transmits a tone signal CE from the receiving side.
D, receiving the low-speed signals NSF, CSI, and DIS;
If the SF maker code matches your transmitter, T
Transmits SI and NSS at low speed. Further, a training check signal TCF is transmitted at a high signal speed specified by NSS.

[0007] The receiver checks the TCF, and if there is no error, sends out a reception preparation confirmation signal CFR.

[0008] The transmitter transmits the reception preparation confirmation signal CFR.
Is received, the image data PIX is transferred at the high signal speed specified by the NSS.

[0009]

However, in the above-described communication protocol in the facsimile apparatus of the G3 standard, it takes about 13 seconds until image data is actually transmitted. This time is more than twice as long as, for example, the transmission time of one A4 size document is about 6 seconds at a communication speed of 14.4 KBPS.

Therefore, it is desired to reduce the control procedure time until image data transmission, and the following method has been considered as a method of reducing the control procedure time.

[0011] That is, a control procedure for communicating a communication procedure signal by a low-speed modem and a control procedure for communicating a communication procedure signal by a high-speed modem are provided. As shown in the signal sequence diagram of FIG. After that, the transmitting side repeatedly sends a high-speed procedure request signal (corresponding to NSS, hereinafter referred to as SNSS) by the low-speed modem without detecting the line connection, and the called side receiving the high-speed procedure request signal SNSS A high-speed procedure acknowledgment (corresponding to NSF) for a high-speed procedure request signal.
) Is transmitted by the low-speed modem, and after transmitting the high-speed procedure acknowledgment SNSF, the control procedure is performed by the high-speed modem.

More specifically, as shown in the flow charts of FIGS. 6 and 7, the transmitting side first dials the destination telephone number when the transmission key is pressed by the operator (step 11). After completion of the dialing, an interval of several seconds is taken (step 12). This interval is taken because the line is not connected immediately after dialing. Next, a timer T (other party response waiting period) is started (step 1).
3) Then, CNG of 1100 Hz is transmitted for 0.5 seconds (step 14), and thereafter, at intervals of 75 ms (step 15), the high-speed procedure request signal SNSS is transmitted at a low speed (step 16).

Next, the reception of the low-speed signal and the CED is prepared, and the timer T1 is started (step 17).
When the high-speed procedure request signal SNSS is transmitted at a rate of two per CNG signal, the value of the timer T1 is appropriately about 0.8 seconds. Until the above-mentioned timer T1 times out, a process of detecting whether or not the high-speed procedure acknowledgment SNSF has been transmitted from the receiver (step 18), and CED, NSF, CS
A process for detecting whether or not I and DIS have been transmitted (step 19) is performed.

In step 18, the high-speed procedure acknowledgment SN
If SF is detected, the procedure proceeds to the high-speed procedure (Step 29). If not detected, the procedure proceeds to Step 19. If the CED or the like is detected, the procedure proceeds to the standard procedure (Step 28). If a timeout has occurred without any detection (YES in step 20), the second high-speed procedure request signal SNSS for one CNG signal is transmitted (step 21), and the timer T2 is started (step 22). . After that, the same processing as the above-mentioned steps 18 to 20 is repeated (steps 23 to 25).
To determine whether the timeout has occurred (step 2
6). If the timer T has not timed out, the process proceeds to step 14, while if the timer T has timed out, it is determined that the other party has not responded and the line is disconnected (step 2).
7).

The receiving side detects whether there is an incoming call as shown in the flowchart of FIG. 8 (step 31),
If there is an incoming call, the line is connected (step 32), and a timer is started (step 33). Then, neither CNG nor SNSS is detected (N in step 34).
If the timeout has occurred (O, NO in step 35), a timeout occurs (YES in step 36), it is determined that the partner device is a device having no high-speed procedure, and a CED or the like is transmitted in accordance with the procedure of the G3 machine (step 37), and (Step 38).

If CNG is detected in step 34 (YES in step 34), another timer is started (step 41). Next, if the other device is a device having a high-speed procedure, an SNSS
Is transmitted, it is detected whether SNSS is transmitted (step 42).

If the SNSS is not detected (NO in step 42) and a timeout occurs (Y in step 43)
ES), the process proceeds to step 37, where CED or the like is transmitted (step 37), and the process proceeds to the standard procedure (step 38).

On the other hand, when the SNSS is detected in step 35 and when the SNSS is detected in step 42, it is determined that the partner device is a device having a high-speed procedure, and a high-speed procedure acknowledgment SNSF is transmitted. (Step 39), proceed to the high-speed procedure (Step 40).

By employing such a communication method, a control procedure after transmitting the SNSF can be performed at a high speed.

On the other hand, the calling side determines a tone signal (for example, a dial tone, a ringback tone, or a busy tone) from the station by the modem, and sets a redial condition in accordance with the determined tone signal. It is carried out.

However, in the above communication method, the calling side must repeatedly send a high-speed procedure request signal after dialing. Normally, the tone signal is determined by checking the tone frequency and the ON / OFF pattern by the modem. However, when the modem is transmitting a signal, the modem cannot generally detect the tone. Therefore, as described above, the high-speed procedure request signal SNSS
Is repeatedly transmitted, it is difficult to recognize the tone signal from the station.

The present invention has been made in view of the above circumstances, and has as its object to provide a facsimile communication method capable of determining a tone signal from a station while realizing a high-speed procedure in the communication method.

[0023]

In order to solve the above-mentioned problems, a facsimile communication method according to the present invention has a control procedure for transmitting and receiving a communication procedure signal by a low-speed modem and a control procedure for transmitting and receiving a communication procedure signal by a high-speed modem. After the calling-side dialing, the calling side repeatedly sends a high-speed procedure request signal by the low-speed modem without detecting the line connection, and the called side receiving the high-speed procedure request signal transmits the high-speed procedure request signal. This is a facsimile communication method in which the high-speed modem communicates the subsequent control procedures when a high-speed procedure response signal, which is a response of the high-speed procedure, is transmitted by the low-speed modem. Detect presence,
When a tone is detected, the transmission of the high-speed procedure request signal is stopped.

[0024]

According to the above arrangement, when a tone is detected, a high-speed procedure request signal is not transmitted, so that the modem can determine the tone signal by checking the tone frequency and the ON / OFF pattern. Become.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing the embodiments.

FIG. 1 is a block diagram showing the configuration of a facsimile apparatus according to the present invention.

The operation unit 1 includes various keys such as one-touch dial keys and numeric keys, a liquid crystal display, and the like. By the user operating the above keys,
The operation signal is provided to the main control unit 3.

The reading section 2 is composed of an image sensor such as a CCD, reads a document placed on a document table (not shown), and outputs the image data to the main control section 3.

The main control unit 3 controls the entire apparatus, and is a microcomputer peripheral device such as a ROM (not shown) storing a microcomputer and a control program, and a RAM temporarily storing various data. And controls the encoding and decoding of the image signal and the execution of the communication procedure.

The recording section 4 is constituted by a thermal printer or a laser printer or the like, and drives a head based on image data supplied from the main control section 3 to perform printing on recording paper.

The low-speed modem 5 is a low-speed modem defined by ITU-T Recommendation V21, and is used for communication in a normal control procedure. On the other hand, the high-speed modem 6 is a high-speed modem defined by ITU-T recommendations V27ter, V29, V33, and V17. To determine the tone signal from the station,
This is done by the modem monitoring the tone frequency and the ON / OFF pattern. The modem continuously monitors the tone signal during communication, but cannot detect the tone when transmitting the signal.

The network control unit (NCU) 7 is connected to the line 8 and detects a call signal from the line 8 to determine an incoming call as a process at the time of receiving a call, and performs a main control as a process at the time of calling. For example, dialing of the telephone number of the other party is performed.

Next, the procedure before the high-speed procedure in the facsimile apparatus of the present invention will be described with reference to the flowcharts of FIGS.

[Procedure on Transmitter Side] FIG. 2 is a flowchart showing a part of the control procedure before the high-speed procedure on the transmitter side, and FIG. 3 is a flowchart showing the control procedure of the remaining part. .

On the transmitting side, first, when the transmission key is pressed by the operator, dialing of the other party's telephone number is performed (step 51), and an interval of several seconds is taken after completion of the dialing (step 52). Next, a timer T (other party response waiting period) is started (step 53), and then CNG of 1100 Hz is transmitted for 0.5 seconds (step 54), and after an interval of 75 ms (step 55), Is detected (step 56). The tone signal recognition process (tone frequency and ON / OFF pattern detection)
It is always performed except when transmitting a signal.

If no tone from the station is detected in step 56, the high-speed procedure request signal SNSS is transmitted at a low speed (step 57), and the flow advances to step 58.
On the other hand, if a tone from the station is detected, the process proceeds to step 58 without transmitting the high-speed procedure request signal SNSS.

In step 58, the timer T1 is started. Note that the set value of the timer T1 differs depending on whether the process goes through step 57 or not. Timer T described later
The same applies to No. 2. Until the timer T1 times out, a process of detecting whether the high-speed procedure acknowledgment SNSF has been transmitted from the receiver side (step 59), and detecting whether CED, NSF, CSI, and DIS have been transmitted. The processing (step 60) is performed.

In step 59, the high-speed procedure acknowledgment SN
If the SF is detected, the procedure proceeds to the high-speed procedure (step 71). If the SF is not detected, the procedure proceeds to step 60. If the CED or the like is detected, the procedure proceeds to the standard procedure (step 70). If a timeout occurs without any of them being detected (YES in step 61), the presence or absence of a tone from the station is detected (step 62). If the tone from the station is not detected, the second high-speed procedure request signal SNSS for one CNG signal is transmitted at a low speed (step 63), and the process proceeds to step 64, while the tone from the station is detected. If so, step 64 without sending a signal.
Proceed to.

In step 64, the timer T2 is started. Thereafter, the same processing as the above-mentioned steps 59 to 61 is repeated (steps 65 to 67), and when the timer T2 times out, it is determined whether or not the timer T has timed out (step 68). If the timer T has not timed out, the process proceeds to step 54, while if the timer T has timed out, it is determined that the other party has not responded and the line is disconnected (step 69).

[Receiver side procedure] The receiver side executes a reception procedure in accordance with the flowchart of FIG. 6 shown in the conventional example.

FIG. 4 is a diagram showing a state in which the transmission of the high-speed procedure request signal SNSS is stopped in relation to the tone signal received from the station by the transmission procedure of the flowcharts shown in FIGS. is there. More specifically, FIG. 4A shows a pattern of CNG and a high-speed procedure request signal SNSS repeatedly transmitted after dialing on the calling side, and FIG. 4B shows a pattern of a busy tone. 3C shows a state in which the transmission of the high-speed procedure request signal SNSS is stopped by the busy tone, FIG. 4D shows a pattern of the ring-back tone, and FIG. 6E shows a pattern of the high-speed procedure request signal SNSS by the ring-back tone. FIG. 9 is a diagram illustrating a state in which transmission is stopped.

As shown in FIGS. 4C and 4D, if a tone is detected before the transmission of the high-speed procedure request signal SNSS, the high-speed procedure request signal SNSS is not transmitted. Since the modem can continue to detect the tone and check the tone frequency and the ON / OFF pattern, the tone signal can be surely recognized.

When a busy tone is recognized, a line disconnection process is performed. FIG. 4C does not show a line disconnection process when a busy tone is recognized.
This shows non-transmission or only transmission of SNSS due to tone detection or non-detection.

On the other hand, when the ringback tone is recognized, the high-speed procedure request signal SNSS continues after this recognition.
Must be sent repeatedly. Since it is not particularly necessary to stop the transmission of the high-speed procedure request signal SNSS for tone signal recognition after the ringback tone has been recognized, the high-speed procedure request signal SNSS is output regardless of tone detection after tone recognition. It may be sent.

FIG. 5 is a diagram showing a state in which the transmission of the high-speed procedure request signal SNSS is stopped by the ringback tone. FIG. 5A shows a case where the called party receives a call and responds to the standard procedure. FIG. 6B is a diagram showing a case where a called party receives a call and responds in a high-speed procedure.

That is, according to the communication method of the present invention, it is possible to realize a high-speed procedure while reliably determining a tone signal.

[0047]

As described above, according to the present invention, when the tone transmitted from the station is detected on the calling side, the high-speed procedure request signal is not transmitted, so that the modem continues to detect the tone. By checking the tone frequency and the ON / OFF pattern, the tone signal can be reliably recognized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a facsimile apparatus of the present invention.

FIG. 2 is a flowchart showing a part of a transmission side process in the facsimile communication method of the present invention.

FIG. 3 is a flowchart showing the remaining part of the transmission-side processing in the facsimile communication method of the present invention.

FIG. 4 is a diagram showing a state in which transmission of a high-speed procedure request signal is stopped in relation to a tone signal received from a station according to the transmission procedure of the flowcharts shown in FIGS. 2 and 3.

FIG. 5 is a diagram illustrating a state in which transmission of a high-speed procedure request signal SNSS is stopped by a ringback tone and a partner device responds by a standard procedure or a high-speed procedure.

FIG. 6 is a flowchart showing a part of a process in which a calling side repeatedly transmits a high-speed procedure request signal by a low-speed modem without detecting a line connection.

FIG. 7 is a flowchart showing a remaining processing part with respect to FIG. 6;

FIG. 8 is a flowchart showing a process considered to be performed on the receiving side corresponding to the process on the transmitting side shown in FIGS. 6 and 7;

FIG. 9 is a signal sequence diagram showing a communication procedure according to FIGS. 6 to 8;

FIG. 10 is a signal sequence diagram showing a communication procedure in a G3 standard facsimile machine.

[Explanation of symbols]

 Reference Signs List 1 operation unit 2 reading unit 3 main control unit 4 recording unit 5 low speed modem 6 high speed modem 7 NCU

Claims (1)

(57) [Claims] 1. A control procedure for transmitting / receiving a communication procedure signal by a low-speed modem and a control procedure for transmitting / receiving a communication procedure signal by a high-speed modem, and after the dialing of the calling side, the calling side detects a line connection. The high-speed procedure request signal is repeatedly transmitted by the low-speed modem without performing, and the called party receiving the high-speed procedure request signal transmits the high-speed procedure response signal, which is a response to the high-speed procedure request signal, by the low-speed modem. Is a facsimile communication method for communicating with a high-speed modem, and detects the presence or absence of a tone from a station before transmitting each high-speed procedure request signal, and stops transmitting the high-speed procedure request signal when a tone is detected. A facsimile communication method characterized in that: