KR100571959B1 - Method for changing transmitting/receiving mode of facsimile - Google Patents

Abstract

The present invention relates to a method for operating a facsimile, and a method for changing a transmission / reception mode of a facsimile for changing a transmission / reception mode of the facsimile information according to a state of a line line for transmitting / receiving information. The method of changing the sending / receiving mode of the facsimile is a method of transmitting the facsimile data, selecting an option to switch from the G3 mode that allows the sending / receiving data loss to the ECM mode without the sending / receiving data, and setting the standard transmission / reception speed of the modem to execute the option. After receiving the signal for requesting readjustment of the transmission speed from the receiving side after forming a call loop and transmitting the training data for determining the transmission / reception mode and the speed of the modem, the transmission speed of the current modem and the reference transmission / reception speed of the established modem are determined. In comparison, when the transmission speed of the current modem becomes the reference transmission / reception speed of the established modem, switching from the current transmission mode G3 mode to the ECM mode. According to the present invention, stable transmission and reception of facsimile data is possible even in a bad line state due to noise or the like. In addition, it reduces the communication time on the user side and enables the transmission and reception of data without error.

Description

How to change the sending / receiving mode of a fax {Method for changing transmitting / receiving mode of facsimile}

1 is a flowchart illustrating the operation of a conventional facsimile transmission method.

2 is a block diagram showing the configuration of a facsimile.

3 is a flowchart illustrating an operation of a method for setting a transmission / reception change mode of a user in the method for changing a fax transmission / reception mode according to the present invention.

4 is a flowchart illustrating an operation of a method of changing a facsimile transmission / reception mode of a transmitting side according to the present invention.

5 is a flowchart illustrating an operation of a method of changing a facsimile transmission / reception mode of a receiving side according to the present invention.

The present invention relates to a method for operating a facsimile, and more particularly, to a method for changing a transmission / reception mode of a facsimile for changing a transmission / reception mode of the facsimile information according to a state of a line line for transmitting / receiving information.

A facsimile machine is a device that outputs fax data transmitted through a telephone line from a transmitting side or allows a user to transmit fax data through an identical telephone line to an arbitrary receiving side. These facsimile machines typically include the functions of scanners, printers and telephones, and have recently been used as essential office automation equipment (OA) in homes and offices.

In general, the transmission and reception mode of the facsimile is the G3 mode in which a protocol method for transmitting and receiving image data is allowed according to the International Telecommunication Union (ITU) Recommendation T.30. It is divided into Error correction mode (ECM) that retransmits and recovers data.

G3 mode is one of the facsimile standards recommended by the International Telegraph and Telephone Advisory Committee (CCITT), which processes the screen signal digitally and increases the number of pixels to achieve the same resolution as in analog. Such a facsimile service using G3 has a limitation that can be used only through a general public switched telephone network in view of the current trend of using a digital mobile communication network.

ECM mode is an option of the ITU-T.30 protocol, which may cause errors due to line problems when sending and receiving facsimile images. The facsimile image binary data is analyzed to detect and recover the errors.

G3 mode can save communication time even if loss of data is allowed. ECM mode has no difference in data loss regardless of communication time.

1 is a flowchart illustrating the operation of a conventional facsimile transmission method. First, when a user feeds a plurality of transmission documents to be sent to a document feeder, the sending side facsimile performs a message transmission preparation step to prepare for message transmission. .

That is, the transmitting side facsimile transmits a calling tone (CNG: Calling Tone) indicating the start of transmission to the receiving side facsimile via the modem, the LIU, and the PSTN (step 100).

When the receiving fax machine connects the line by making a call from the sending fax machine, the receiving fax machine receives a response signal to the call tone (CNG), that is, a called station call (CED: Called Station Identification). ) Transmit the tone to the sending side facsimile for a certain period of time and indicate the standard function of the called station of the International Telegraph and Telephone Advisory Committee (CCITT), ie informing its own reception capability such as modem speed / compression method / resolution In step 102, a digital identification signal (DIS) frame for a predetermined time is transmitted to the transmitting side facsimile.

At this time, the sending fax checks the contents of the called station identification (DIS) frame sent from the receiving fax and compares the parameters set in the sending fax with the parameters of the receiving fax, and the modem speed / compression method / resolution for actual transmission. After setting the parameters of the receiver, it is carried in a response (DCS: Digital Command Signal) frame to the called party identification (DIS) frame and transmitted to the receiving side facsimile (step 104).

In addition, the sending side facsimile determines the initial transmission / reception speed, the transmission / reception scheme of the G3 and ECM modes, and zeros the data at a modem speed that is already set for training to determine the actual communication speed. Training Check (TCF) data transmitted for 1.5 seconds is transmitted to the receiving side facsimile through the modem, the LIU, and the PSTN (step 106).

The receiving side facsimile checks the training (TCF) data at the modem speed (i.e., transmission rate) already set through the sending side facsimile's response (DCS) frame. Sends a FAX (Fail To Train) frame to request reconditioning and transmits it.

When the sending side fax receives the FTT frame from the receiving side fax, the modem speed is lowered by one step regardless of the error rate of the data, and the response (DCS) frame and training (TCF) data is set to the lowered modem speed by the first step. Send back to the receiving fax.

The receiving side facsimile checks the training (TCF) data again at the modem speed already set through the sending side facsimile's response (DCS) frame. If the error still exceeds a certain rate, the modem returns to the sending side facsimile. It will send an FTT frame to request the rate readjustment.

When the receiving side fax receives another FTT frame from the receiving side facsimile, the modem speed is lowered by one step and the DCS and TCF data is transmitted back to the receiving side facsimile.

In addition, the transmitting side facsimile gradually decreases the modem speed by one step until the receiving side receives a Confirmable To Receive (CFR) frame indicating that the training data has been successfully received from the receiving side facsimile (305). And repeating the retransmission of the TCF data (step 108).

When the sending fax receives a Receivable (CFR) frame indicating that it has successfully received the training data from the receiving fax, the sending fax scans and sends the fax's actual image data, that is, the original data, at the preset modem speed, and then sends the next message. The operation of the step is performed (step 110).

As described above, the conventional facsimile attempts to communicate only in the G3 mode or the ECM mode defined by the user, even when performing a fallback due to a noise problem of a transmission / reception line. If noise is excessively generated in the transmission / reception line, data received in the G3 mode may be distorted to such an extent that image recognition is impossible.

The technical problem to be achieved by the present invention is to change the transmission and reception mode of the facsimile changing the transmission and reception mode of the facsimile information in accordance with the state of the line line for transmitting and receiving information in order to enable stable transmission and reception of the facsimile data even if the transmission and reception line conditions are not good To provide a method.

A method for changing a transmission / reception mode of a facsimile to solve the above technical problem to be solved by the present invention is a method of transmitting a facsimile data, comprising: (a) switching from a G3 mode allowing loss of transmission / reception data to an ECM mode without loss of transmission / reception data; Selecting an option and setting a reference transmit / receive rate of a modem for executing the option; (b) forming a call loop and receiving a signal for requesting readjustment of the transmission rate from the receiving side after the transmission of the training data for determining the transmission / reception mode and the speed of the modem; Comparing transmission and reception speeds; And (c) switching from the current transmission mode to the ECM mode when the transmission speed of the current modem becomes the reference transmission / reception speed of the modem.

According to the present invention, after the training data is transmitted, if the signal for requesting the transmission rate readjustment of the modem is not received from the receiving side, the actual image data is transmitted without changing the transmission / reception mode.

A method for changing a transmission / reception mode of a facsimile for solving the above technical problem to be solved by the present invention is a method of receiving a facsimile data, which includes: (a) the present invention in the process of receiving training data for determining a transmission / reception mode and a speed of a modem from a transmitter; Checking a transmission / reception line state; (b) when the current transmission / reception line state exceeds a reference value, switching from the G3 mode allowing loss of transmission / reception data to an ECM mode without loss of transmission / reception data; And (c) receiving image data transmitted from a transmitting side when the current transmission / reception line state is equal to or less than a reference value and no error occurs in the training data.

In the present invention, after step (b), the transmitting side requests for retransmission of training data according to a mode change.

In the present invention, when an error occurs in the training data in the step (c), it is characterized in that for transmitting to the transmitting side a signal for requesting the speed readjustment of the modem.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

FIG. 2 is a block diagram showing a facsimile configuration, which includes a LIU 200, an amplifier 202, a CODEC 204, a speaker 206, a HANDSET 208, a print unit 210, a SCAN unit 212, and an OPE. 214, the CPU, the MODEM 216, and the memory 218.

The LIU (Line interface unit) 200 forms a DC loop when interfacing with a general PSTN network and is responsible for transmitting and receiving analog signals such as network connection and network switching, and providing tone generation, tone detection, and HANDSET 208 interface. And many other features. In FIG. 2, the MODEM part is classified separately for convenience, but it may be designed to be included in the LIU.

The amplifier 202 amplifies and attenuates the analog signal transmitted to the LIU 200 in accordance with a physical communication standard.

The CODEC 204 transmits voice data to a PSTN network, converts a received analog voice signal into a digital signal, or converts a digital signal into an analog signal.

The print unit 210 is composed of a motor that performs printing and other circuits, and is responsible for printing image data.

The SCAN unit 212 is a part that converts an optical signal of image input data into an electrical signal.

OPE (Operating pannel) is a key-panel unit that provides a user with a terminal to operate.

CPU and MODEM 216 is a control unit for controlling all functions of the terminal device, which may include additional circuits in addition to the CPU, MODEM, but does not enumerate one by one.

The memory 218 stores system programs, data, and the like.

3 is a flowchart illustrating an operation of a method of setting a transmission / reception change mode of a user in a method of changing a facsimile transmission / reception mode according to the present invention. The user may activate the ECM automatic switching function of the G3 mode in USER OPTION. You can select the reference fallback speed at the time of transition. When the user selects the function of switching the G3 mode to the ECM mode in the USER OPTION (step 300), the reference fall-back speed is set (step 302). Here, the reference fall-back rate is a reference rate for switching from G3 mode to ECM mode when the modem speed specified by the receiver by the fall-back of the receiving end is reached.

When the user activates the ECM phone mode in the USER OPTION, the transmission and reception operation procedures are as shown in FIGS. 4 and 5.

4 is a flowchart illustrating an operation of a method of changing a facsimile transmission / reception mode of a transmitting side according to the present invention.

First, when the user feeds a plurality of transmission documents to be sent to the document feeder (not shown), the sending side fax performs a message transmission preparation step to prepare for message transmission.

That is, the transmitting side facsimile transmits a call tone (CNG) indicating the start of transmission to the receiving side facsimile through the modem 216, the LIU 200, and the PSTN (step 400).

In this way, when the receiving side facsimile device makes a call and the receiving side facsimile device connects the line, the sending side facsimile receives a response signal to the call tone (CNG) from the receiving side facsimile, that is, the called party's call (CED). Called Station Identification Receives a tone for a predetermined time and indicates the recipient's standard function of the International Telegraph Telephone Advisory Committee (CCITT), that is, its reception capability such as modem 216 speed / compression method / resolution In step 402, a receiver receives a Digital Identification Signal (DIS) frame to inform the user of the message.

At this time, the sending fax checks the contents of the called station identification (DIS) frame sent from the receiving fax, compares the parameters set in the sending fax with the parameters of the receiving fax, and then compares the speed / compression of the modem 216 for actual transmission. After setting the parameters such as the method / resolution, they are loaded in a response (DCS: Digital Command Signal) frame to the called station identification (DIS) frame and transmitted to the receiving side facsimile (step 404).

And the sending side facsimile is zero data at the modem speed already set for training, that is, to determine the initial transmission / reception speed and the transmission / reception scheme of the G3 and ECM modes and to determine the actual communication speed. ) Is transmitted to the receiving side facsimile through the modem 216, the LIU 200, and the PSTN (step 406).

In the receiving facsimile, if the training (TCF) data is checked through the response (DCS) frame of the sending facsimile at the speed (i.e., transmission speed) of the modem 216 that is already set, and error occurs more than a certain ratio, The sender facsimile transmits a signal to the sender facsimile (FTT: Failure To Train) frame for requesting modem speed readjustment, and the sender facsimile determines whether a FTT frame has been received from the receive facsimile (step 408).

When the transmitting side fax receives the FTT frame for the speed re-adjustment of the modem 216 from the receiving side fax, it is determined whether the current modem speed is the reference fall-back rate set by the user in step 302 of FIG. 3 (step 410). ).

If the current modem speed is the reference fall-back speed, the current G3 mode is switched to the ECM mode (step 412). After converting the G3 mode to the ECM mode, the DCS frame and the re-trained training data are transmitted from the receiving side facsimile, and then the process is repeated.

When the sending fax receives a Confirmation To Receive (CFR) frame indicating that it has successfully received the training data from the receiving fax, it scans the facsimile's actual image data, that is, the original data, at the preset modem speed. In operation 414, the operation of the next message transmission step is performed.

5 is a flowchart illustrating an operation of a method of changing a facsimile transmission / reception mode of a receiving side according to the present invention.

That is, the receiving side fax receives a Calling Tone (CNG) indicating the start of transmission from the transmitting side fax through the modem 216, the LIU 200, and the PSTN (step 500).

When the receiving fax machine connects the line by making a call from the sending fax machine, the receiving fax machine receives a response signal to the call tone (CNG), that is, a called station call (CED: Called Station Identification). ) Transmits a tone to the sending side facsimile for a predetermined time, and indicates the standard function of the called station of the International Telegraph Telephone Advisory Committee (CCITT), that is, its reception capability such as modem 216 speed / compression method / resolution In step 502, a Digital Identification Signal (DIS) frame for notifying the transmitter is transmitted to the transmitting side facsimile.

At this time, the sending fax checks the contents of the called station identification (DIS) frame sent from the receiving fax, compares the parameters set in the sending fax with the parameters of the receiving fax, and then compares the speed / compression of the modem 216 for actual transmission. After setting the parameters such as the method / resolution, the receiver side facsimile receives the received FAC (Digital Command Signal) frame and transmits the received facsimile (step 504).

Then, the receiving side facsimile is zero at the modem speed already set for training, that is, the modem 216 speed control to determine the initial transmission / reception speed and the transmission / reception scheme of the G3 and ECM modes from the transmission side facsimile, and to determine the actual communication speed. Training Check (TCF) data for transmitting zero data for about 1.5 seconds is received through the modem 216, the LIU 200, and the PSTN (step 506).

The receiving side facsimile receives the first training data and determines whether an EQM (Eye quality monitor) value representing the current line state exceeds a reference value (step 508). The receiving facsimile needs to receive the first training data and check the current line state. The procedure for checking the line state can refer to the S / N ratio characteristic, and also to receive the facsimile data. Use EQM value. The EQM is a line-quality probing vector calculated based on the amplitude and phase components of the received signal at each modem speed, and thus description thereof is omitted. The receiving facsimile evaluates the stability of the line by calculating the EQM value in the course of receiving the training data, and determines that the line state is not good when the predefined reference value is exceeded.

If the EQM (Eye quality monitor) value indicating the current line state exceeds the reference value, the line state is not good, so the G3 mode is switched to the ECM mode (step 510). This resets the G3 mode field in the DIS frame of the receiving facsimile and sets it to ECM mode so that the sending facsimile can transmit in ECM mode. However, if the sending facsimile does not support the ECM mode, communication can be made in the G3 mode even by changing the DIS frame of the receiving facsimile.

If the EQM (Eye quality monitor) value indicating the current line status is less than the reference value, and the line condition is good, the receiving side facsimile speed (i.e., transmission speed) of the modem 216 already set through the sending side facsimile response (DCS) frame. Check the training (TCF) data to determine whether more than a certain error rate (step 512).

In case of an error more than a certain rate by checking the training (TCF) data, a FFT (Fail To To Train) frame for requesting modem speed readjustment is transmitted to the transmitting side facsimile (step 514). . Upon receiving the FTT frame, the transmitting side facsimile transmits the DCS frame and the retrained training data to the receiving side facsimile and repeats the process.

If no error occurs over a certain rate by checking the training (TCF) data, the receiving side fax sends a Confirmation To Receive (CFR) frame indicating that the training data has been successfully received. In step 516, the processor transmits the message to the processor.

Thereafter, the receiving side facsimile receives the actual image data of the facsimile, i.e., scanned original data, from the transmitting side facsimile at the preset modem speed, and then performs the operation of the next message receiving step (step 518).

So far I looked at the center of the preferred embodiment for the present invention. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

As described above, according to the present invention, even when the line state is not good due to noise or the like, stable transmission and reception of the facsimile data is possible. In addition, it reduces the communication time on the user side and enables the transmission and reception of data without error.

Claims (5)

As a method of sending facsimile data, (a) selecting an option for switching from the G3 mode allowing loss of transmission / reception data to an ECM mode without loss of transmission / reception data, and setting a reference fallback speed of the modem for executing the option; (b) after receiving a signal for requesting readjustment of the transmission rate from the receiving side after forming a call loop and transmitting the training data for determining the transmission / reception mode and the speed of the modem, the transmission rate of the current modem and the reference poll of the set modem. Comparing bag speeds; And and (c) when the transmission speed of the current modem becomes the reference fallback speed of the set modem, switching from the current transmission mode G3 mode to the ECM mode. The method of claim 1, And transmitting the actual image data without changing the transmission / reception mode if the signal for requesting readjustment of the transmission speed of the modem is not received from the reception side after the training data transmission. As a method of receiving facsimile data, (a) In the process of receiving the training data for determining the transmission / reception mode and the speed of the modem from the transmitting side, using the line-quality probing vector value calculated based on the amplitude and phase components of the received signal at the speed of the modem. Checking a transmission / reception line state; (b) when the current transmission / reception line state exceeds a reference value, switching from the G3 mode allowing loss of transmission / reception data to an ECM mode without loss of transmission / reception data; And and (c) receiving image data transmitted from a transmitting side when the current transmission / reception line state is equal to or less than a reference value and no error occurs in the training data. 4. The method of claim 3, wherein after step (b) A method of changing a transmission / reception mode of a facsimile, characterized by requesting retransmission of training data according to a mode change from a transmitter. The method of claim 3, wherein in step (c) And transmitting a signal for requesting speed adjustment of the modem to the transmitting side when an error occurs in the training data.

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