JP3380514B2 - Data communication device and facsimile 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 data communication device and a facsimile for reducing the time required for a pre-procedure in data communication using a modem, for example, facsimile communication.
It relates to the device .

[0002]

2. Description of the Related Art Recently, in this type of data communication apparatus, I
V. as specified in TU-T. 34 modem (28.
Data communication of 8 kbps) is performed. Also in the facsimile machine, the above V. T30A NEXF (so-called super G3) has been recommended by ITU-T as a communication standard for facsimiles using a 34 modem, and communication of image data is performed by executing a communication procedure in accordance with this communication standard.

The communication procedure will be described based on the sequence diagram shown in FIG. FIG. 12 is a control signal diagram of a pre-procedure for facsimile communication according to the related art. In FIG. 12, 1
0a is a communication procedure for selecting a modulation mode from V34 half duplex, V34 full duplex, V17 half duplex, and the like. Reference numeral 10b is a communication procedure related to line probing for inspecting the line and determining various parameters. 10c is a communication procedure for modem training. 10d is a communication procedure for setting modem parameters. 10e is a communication procedure of a facsimile control signal. 10f is a data communication procedure of the main channel. The upper side of the figure is the calling side sequence, and the lower side is the called side sequence. The sequence progresses from left to right.

The operation of the communication procedure configured as above will be described. First, after the line connection, in the communication procedure 10a for selecting the modulation mode, V. 21 modems (300 bps,
Full-duplex) is used to select the modulation mode and communication protocol that allow the calling and called sides to communicate with each other. V. In a facsimile machine using a H.34 modem, V.34 is used as the modulation mode.
34 Modem, and facsimile communication is selected as the communication protocol.

After that, the communication procedure 10 for line probing
In b, the calling party sends a line probing tone,
The call reception side receives the line and performs line inspection, and the training parameter is selected based on the line inspection result.

In the communication procedure 10c for modem training, a training signal is transmitted from the calling side based on the training parameters selected in the communication procedure 10b for line probing, and the training signal is received by the called side to determine the line characteristics. Learning of filter coefficient of adaptive equalizer for correction and reception quality inspection of training signal.

In the communication procedure 10d for selecting modem parameters, a 1200-bps full-duplex modem negotiates modem parameters between the calling side and the called side, and the modem parameters preset in the device and the above-mentioned Optimal modem parameters are selected from the line inspection result and the reception quality inspection of the training signal.

In the facsimile control signal communication procedure 10e, the facsimile control signals NSF, CSI, DIS, TSI, DCS,
Negotiation such as CFR is performed.

In the data communication procedure 10f, 2400 bp
A half-duplex modem from s to 28.8 kbps transmits image data from the calling side and receives the image data on the called side. When communicating at the maximum communication speed of 28.8 kbps, image data can be communicated in about 3 seconds per A4 sheet. The modem communicates according to the training parameter selected in the communication procedure 10b for communication line probing and the modem parameter selected in the communication procedure 10d for selecting modem parameter. The modem on the receiving side communicates using the filter coefficient learned in the modem training 10b in order to correct the line characteristic. By doing this,
Optimal data communication is performed according to the line quality.

[0010]

However, in the above-mentioned configuration of the prior art, about 7 seconds are required because a pre-procedure of 5 steps is required from the line connection to the start of the transmission of the image data. On the other hand, since the transmission time of one image data at the maximum communication speed of 28.8 kbps is about 3 seconds, when sending only one image, the total time required for the transfer is 11 seconds including about 1 second of the post procedure. On the other hand, the proportion of the pre-procedure reaches 60% or more. Therefore, as the number of transmissions and receptions increases, it is a waste that cannot be ignored in terms of communication time and communication cost.

In many cases, the facsimile machine is actually used, and only one facsimile machine is connected to one line, and the same modulation mode is always selected for the same communication partner. Therefore, if the previous communication mode is stored, it is not necessary to perform the modulation mode selection procedure for each communication.

Further, with the recent spread of digital exchanges, the difference in line characteristics due to the difference in paths in the exchanges disappears, and the same line characteristics are always obtained for the same communication partner. If it is stored, it is not necessary to perform the communication procedure related to the line probing for each communication.

Further, the training time is set according to the learning time of the filter coefficient of the adaptive equalizer on the receiving side, but normally, the training time is set long enough to satisfy all the lines. is doing. For this reason, in the case of a good line, the learning time of the filter coefficient may be shorter than the normal setting, which may result in a dead time of training.

The present invention, since <br/> is because in view of the problems described above, removes the communication procedure related to the communication procedure and line probing for the modulation mode selection, also optimize the communication procedure of modem training Data communication device and data communication device that can shorten the time of the pre-procedure of the communication procedure
And a facsimile machine .

[0015]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a sender which sends an identification signal in response to an incoming call.
And during the sending of the identification signal, the calling party performs a shortening procedure.
Detection means for detecting a signal indicating or a signal indicating a normal procedure
And information about line characteristics or optimal training time
And a detecting means for storing the shortening procedure.
When the signal is detected, the information stored in the storage means
Omitting transmission of line probing signals based on
Communication means for performing communication according to a procedure .

With this configuration, the short communication procedure can be executed.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a basic block diagram of the facsimile apparatus of this embodiment. In FIG. 1, 101 is a reading unit for reading an original image, and 102 is a recording unit for recording and outputting the received image. Reference numeral 103 denotes a control unit for controlling the entire apparatus, which also performs image signal encoding / decoding processing and communication procedure execution control. 104 is I
The T.T. of TU-T. There is a modem for implementing all the modulation and demodulation of the facsimile communication procedure defined in 30ANEXF, and a digital signal processing unit (D
SP) 104a and an analog front end unit (AFE) 104b having both A / D conversion and D / A conversion functions.
It is composed of. A line control unit (NCU) 105 controls dialing and calling for the line 106. An operation unit 107 includes various key input switches such as a dial key and a start key, and a display device for displaying information. The operation unit 107 is used to perform an operation operation. Reference numeral 108 denotes a memory for storing information corresponding to a communication partner having the function of the shortening procedure. In this example, as shown in FIG. 6, information such as a telephone number and a modem parameter is stored. Modem parameter is a power suppression value indicating signal power, a time value indicating training time, one of two types of high level and low level can be selected and set, carrier selection, pre-emphasis filter selection, and 5 steps to send to eye pattern The speed of the symbol is selected and the training constellation point is selected.

FIG. 2 is a functional block diagram of the digital signal processing unit (DSP) 104a of the modem shown in FIG.
A modem control unit 201 controls an interface with the control unit 103 and various modem functions. Reference numeral 202 is a tonal transmission unit that sends various tonal signals according to the communication procedure, and 203 is a tonal detection unit that identifies the tonal signal sent from the communication partner. 204 is ITU-
V. of T. Used in the communication procedure to select the modulation mode with 21 modems (300 bps, full duplex). 205 is ITU
-V of T. It is an INFO modem (600 bps, full-duplex) that performs INFO sequence communication defined by 34 modems, and is used in the communication procedure of line probing and the start procedure of the shortening procedure. 206 is V. of ITU-T. A control channel modem (1200 bps, full-duplex) defined by the V.34 modem is used. It is used in the setting of modem parameters for the main channel modem of the 34 modem and the communication procedure of the control signal of the facsimile. 207 is V. of ITU-T. 34
Main channel modem (2400 bps to 28.
It is used for image data communication at 8 kbps, half duplex. 208 is V. A line probing transmission unit for transmitting the line probing tone defined in No. 34, and the line probing tone is 150 Hz to 3750 Hz shown in FIG.
It is a combined signal of 21 types of tonal signals up to. 20
Reference numeral 9 is a line probing receiving unit that receives the above-mentioned line probing tone from the communication partner and performs line inspection, and actually performs spectrum analysis on the above received signal by a fast Fourier transform algorithm to determine the optimum symbol rate for the main channel modem 207. , Carrier selection and other modem parameter selection. 210 is V. 34
A training transmission unit 211 transmits a training signal of the modem, and a training reception unit 211 receives the training signal from the communication partner and learns the filter coefficient of the adaptive equalizer for correcting the line distortion.

A block diagram of the training receiving section 211 is shown in FIG. 401 is an analog front end 104b
There is a demodulator that converts the training reception signal Sp A / D-converted in step 1 from the passband to the complex baseband signal Yb, and 402 corrects the line distortion for the baseband signal Yb and outputs the reception signal Yr. Is an adaptive equalizer. Reference numeral 403 is a judging device for judging a judging point Yd for observing a deviation of points in the eye pattern from the received signal Yr. A subtracter 404 subtracts the determination point Yd from the received signal Yr and outputs an error signal Er. The above Yb, Yr, Yd, and Er are signals of complex numbers. The error signal Er is supplied to the adaptive equalizer 402, and the adaptive equalizer 402 learns the internal filter coefficient so that the error signal Er becomes smaller, and the learned internal filter coefficient is the main channel modem 20.
Used as a reception filter coefficient of 7. An absolute value calculator 405 calculates an absolute value of the error signal Er.
An LPF 6 smoothes the output signal Ea of the absolute value unit 405 by low-pass filtering. The output signal of the LPF 406 is E which represents the degree of correction of the line distortion of the adaptive equalizer 402.
Since this is a QM signal, the smaller the EQM signal, the more the line distortion is corrected. 407 is EQ
It is an equalization capability analysis unit that analyzes the correction capability of the line distortion of the adaptive equalizer 402 from the M signal, and from the start of training, the amount of change in the EQM signal is observed until the absolute value of the amount of change becomes smaller than a certain value. Is calculated as the optimum training time (see FIG. 5), and the final value of the EQM signal is noise power, and the training signal power (absolute value from the origin of the point in the eye pattern) vs. noise power (error of the point in the eye pattern) ) Ratio (S
N) is calculated. The optimum training time is used as the training time in the shortening procedure, and the SN is used for selecting the data transfer rate of the main channel modem 207. In the case of the shortening procedure, the optimum training time is not calculated.

The operation of the data communication apparatus configured as above will be described. The operation of the transmitting / calling side will be described. FIG. 7 is a flow chart showing the control operation at the time of transmitting and calling according to the present embodiment. First, calling is started according to the telephone number of the transmission partner and the transmission start instruction from the operation unit 107, and in step S601, the memory 108 is searched for whether or not the telephone number of the transmission partner is registered in the shortened procedure, and is registered. If not, the process proceeds to step S607 to make a dial call. Then, in step S608, ITU-T T30
Facsimile communication is performed by a normal communication procedure based on ANEXF. In the above normal communication procedure, if it is confirmed that the non-standard device signal NSF of the facsimile control signal has the facsimile machine of the transmission partner having the shortened procedure function, the shortened procedure registration flag is set. And step S60
At 9, it is determined whether or not the shortened procedure registration flag is set. If the above flag is not set, the processing ends. If the above flag is set, step S6 is performed.
In step 10, the shortening procedure is registered for the transmission partner, and the process proceeds to step 604. The contents to be registered in the shortened procedure are recorded in the memory 108 according to the memory configuration of the shortened procedure registration memory shown in FIG.

If the shortened procedure is registered in step S601, a dial call is made in step S602, and the shortened procedure communication is performed in step S603. In the above-mentioned shortened procedure communication, the modem parameter of the shortened procedure registration memory is transmitted to the transmission partner in the start procedure, and the communication is performed according to the modem parameter. Then, in step S604, it is determined whether or not there is a communication error, and if there is no communication error, the process proceeds to step S605. Then, in step S605, it is determined whether or not there is a data error during communication, and the process ends when the data error is small. Here, it is conceivable to make the determination based on the number of retransmissions in the ECM.

If it is determined in step S604 that there is a communication error, and if it is determined in step S605 that there are many data errors, the memory 108 is used to clear the shortened procedure registration for the transmission partner in step S606.
And then finish.

Next, the operation of the receiving and receiving side will be described.
FIG. 8 is a flow chart showing the control operation at the time of making and receiving a call in this embodiment. The incoming call is started according to the incoming call instruction from the line 106, and in step S701, the called terminal identification signal ANSam signal is transmitted.

Then, in step S702, the ANS is executed.
The signal from the calling side is detected while transmitting the am signal,
Quick tonal signal (QT
If S) is detected, shortened procedure communication is performed in step S703. In step S702, C in the normal procedure is performed.
When the M signal is detected, the ITU is processed in step S704.
-Perform normal procedure communication according to T30A EXF of T.
At that time, a shortened procedure registration flag indicating that the device itself has a shortened procedure function and an optimum training time are set in the nonstandard device signal NSF of the facsimile control signal in the above-described normal procedure communication.

Next, the communication procedure at the time of registration of the shortened procedure will be described. FIG. 9 is a control signal diagram of a communication procedure at the time of registration of the shortened procedure. Communication procedure for selecting modulation mode after line connection 80
1. Then, the communication procedure 802 for line probing, the communication procedure 803 for modem training, the communication procedure 804 for modem parameter setting, the communication procedure 805 for facsimile control signal, and the pre-procedure are performed, and data (image data) is sent. The data communication procedure 806 is performed.

The communication procedure 801 for selecting the modulation mode will be described. The calling side transmits a calling station identification signal CNG, and the called side transmits a called terminal identification signal ANSam. After that, the calling side transmits a CM indicating a function such as the modulation mode and the communication protocol of the calling side, and the called side transmits a JM indicating a communicable common function according to the received contents of the CM.
When the calling side confirms the JM signal, after transmitting the CJ, it transits to the communication procedure 802 for line probing. The called side also transmits the JM and, after detecting the CJ, transitions to the communication procedure 802 for line probing. CM, JM, C above
J is V. 21 Modem 204 (300 bps, full duplex) is used for communication. Based on the exchange here, for example, V. In the facsimile machine using the H.34 modem, the above V. 34 modem, and facsimile communication can be selected as a communication protocol.

A communication procedure 802 for line probing will be described. The calling side has a preset V.V. 34 INFO0c showing communication capability such as modulation speed and carrier frequency of modem, and line probing tones L1 and L2
To send. The called side transmits INFO0a indicating the preset communication capability and receives a line probing tone. The line probing tone is a composite signal of 21 kinds of tonal signals from 150 Hz to 3750 Hz shown in FIG. Optimal symbol rate, carrier selection and other modem parameter selection for. Then, the called side selects a training parameter that can be communicated from the selected contents and the contents of INFO0c and INFO0a, and
Set O0h and send. Above INFO0c, INF
O0a and INFO0h are INFO modem 205 (600
bps, full duplex). Further, in this communication procedure, as a response signal for synchronization, tone B, iB (180 degree phase with respect to tone B) on the calling side, and
Tones A and iA (180 ° phase to tone A) on the called side are used.

The communication procedure 803 for modem training will be described. The calling side uses the training parameters of INFO0h to train signals S, iS, PP, T.
Send RN. The called side receives the training signal and learns the filter coefficient of the adaptive equalizer 402 for correcting the line characteristic, and the equalization ability analysis unit 407 calculates the optimum training time and the noise power ratio SN. To do.

A communication procedure 804 for setting modem parameters will be described. The calling side and the called side use the procedure synchronization signal PP.
h, modem parameter MP related to ALT and data communication
h and the confirmation signal E of the MPh from the other side are transmitted, and the MPh is exchanged between the calling side and the called side. The MPh on the calling side is a modem parameter preset in the modem on the calling side, and the MPh on the called side is the preset modem parameter and the line inspection result of the line probing tone reception. , The modem parameters selected from the SN calculated from the training signal reception. The communication procedure for setting the modem parameters is the control channel modem 206 (1200 bps, full-duplex modem).
Be communicated using.

The communication procedure 805 of the facsimile control signal will be described. First, the non-standard device signal N from the called side.
SF, called terminal identification signal CSI, digital identification signal DI
Send S. The called side has a flag indicating that the NSF has a shortened procedure function, and the equalization capability analysis unit 4
The optimum training time calculated in 07 is set. The calling side receives the above NSF, CSI, and DIS, and then
After confirming that the called side has the shortened procedure function, the transmitting station identification signal TSI and the digital command signal DSC are transmitted. At that time, the calling party sets the shortened procedure registration flag. The called party transmits the reception preparation confirmation CFR after receiving the TSI and DCS. In cases other than the above, if either the calling side or the called side does not have the shortened procedure function, the shortened procedure registration flag is not set on the calling side. The communication procedure of the facsimile control signal is the control channel modem 206 (1200 bps, full-duplex modem).
Be communicated using.

The main channel data communication procedure 806 will be described. In this communication, the training parameters of INFO0h and the MPh are used to perform communication using modem parameters that satisfy both the calling side and the called side.
The calling side uses the procedure synchronization signals S, iS, P of the main channel.
P and B1 are transmitted, and then PIX (image data) is transmitted. The called side receives the procedure synchronization signals S, iS, PP, B
1 and subsequent PIX (image data) are received. The communication here is a main channel modem 207 (1200 bps
.About.28.8 kbps, half-duplex), and the reception of the main channel modem 207 on the called side is particularly performed by the adaptive equalizer 4 described above.
It is configured to correct the line distortion using the filter coefficient learned in 02. When communicating at the maximum communication speed of 28.8 kbps on the main channel, communication can be performed in about 3 seconds per A4 sheet.

As described above, the communication procedure at the time of registration of the shortened procedure is
By performing the normal procedure as recommended by ITU-T T30ANEXF and by registering the short procedure in the memory 108 on the calling side, it becomes possible to communicate using the short procedure from the next communication. Next, a communication procedure in the shortening procedure will be described. FIG. 10 is a control signal diagram of the communication procedure in the shortening procedure, showing from the connection of the line to the communication of the image data. After the line is connected, the communication procedure 901 for starting the shortened procedure is performed, and thereafter, the communication procedure 902 for modem training and the communication procedure 90 for modem parameter setting are performed by the normal communication procedure.
3, a facsimile control signal communication procedure 904 and a data communication procedure 905 for transmitting data (image data).

The communication procedure 901 for starting the shortening procedure will be described. The calling side transmits a calling station identification signal CNG, and the called side transmits a called terminal identification signal ANSam. The calling party detects the ANSam signal and then sends a quick tonal signal Q
The TS is transmitted, the response signal tone A from the called side is detected, and the tone B and QINFO are transmitted. The called side transmits tone A after detecting the quick tonal signal QTS from the calling side, and receives QINFO from the calling side. The above-mentioned QINFO is contents for each telephone number of the communication partner in the shortened procedure registration memory of FIG. 6, and includes training parameters (INFO0h) at the time of registered shortened procedure, optimum training time,
With the contents of the non-linear distortion correction selection, V. 21 modem 204
(300 bps, full duplex).

Regarding the communication procedure 902 of the modem training, the training parameter (I
NFO0h), communication is performed at the optimum training time.

Communication procedure 9 for setting modem parameters
The setting of the MPh of the called side that communicates in 03 is the above-mentioned QINFO
Selection based on the non-linear distortion correction selection and the SN information calculated in the communication procedure 902 of the modem training.

Regarding the communication procedure at the time of the shortening procedure, only the communication procedure for starting the shortening procedure is carried out by an original procedure, and after the communication procedure of the modem training which follows, the T30ANEX of ITU-T.
Communicate according to the recommendation of F and shorten the pre-procedure.

In the present embodiment, the memory configuration of the shortened procedure registration memory is designed to register the modem parameters in correspondence with the telephone number of the other party as shown in FIG. 6, but the shortened dial key and redial of the operation unit 107 are used. The other party's telephone number and the modem parameter may be registered in association with a key or the like to simplify memory management such as retrieval of the shortened procedure registration memory.

Further, in the present embodiment, the caller side performs the shortening procedure registration corresponding to the telephone number of the other party when dialing.
The modem parameter may be registered on the called side in correspondence with the calling side telephone number of the calling telephone number notification service by the exchange that has started the service in recent years. FIG. 11 shows a flowchart of the processing.

When the telephone number by the calling telephone number notification service is notified from the transmitter side to the receiver side (S801),
The receiver side searches for a telephone number (S802), and if there is a corresponding telephone number (S803, S804), shortened procedure communication is performed (S805). When there is no corresponding telephone number, the normal communication procedure is performed (S806).

A control signal diagram at this time is shown in FIG. When the telephone number is notified, the communication procedure 1001 is performed. In this communication procedure 1001, the receiving side sends a QTS signal to the transmitting side to notify that the shortened communication procedure will be performed. After this, the communication procedure 10 of the modem training is performed in the same manner as the above-mentioned procedure.
02, modem parameter setting communication procedure 1003, facsimile control signal communication procedure 1004, and data communication procedure 1005.

Further, in this control signal diagram, the QTS signal and the QINFO for notifying the modem parameter and the like are separately provided, but the procedure time can be shortened by including information such as the modem parameter and the like in the QTS signal.

By registering information such as modem parameters, optimum training time, and modulation mode in the memory on both the transmitting side and the receiving side, it becomes unnecessary to notify the information in the communication procedure, and the incoming call can be received. Then, the communication procedure 100
It is possible to omit 1 and start from the communication procedure 1002.

By controlling in this manner, it is possible to further shorten the communication time according to the procedure without sending information such as modem parameters from the transmitter side to the receiver side.

As described above, according to the present invention, the normal communication procedure for selecting the modulation mode, the line probing, and the modem training is performed, and the modem parameters selected at that time and the calculated optimum training time are stored in association with the partner telephone number. By doing so, the communication procedure for modulation mode selection and the communication procedure for line probing can be omitted according to the stored modem parameters and optimum training time in the subsequent communication, and the communication procedure for modem training can be performed at the optimum training time. , The time of the pre-communication procedure of communication can be significantly shortened without impairing the communication performance.

[0046]

According to the present invention, the stored modem parameters,
According to the optimum training time, the communication procedure for selecting the modulation mode and the communication procedure for line probing can be omitted, and the communication procedure for the modem training can be performed at the optimum training time. The time of the pre-communication procedure can be significantly reduced without any need.

[Brief description of drawings]

FIG. 1 is a block diagram of the basic configuration of a facsimile apparatus according to this embodiment.

FIG. 2 is a functional configuration diagram of a digital signal processing unit (DSP) shown in FIG.

FIG. 3 is an explanatory diagram showing a tone group of a line probing tone signal.

FIG. 4 is a block diagram of the training receiving unit shown in FIG.

5 is an explanatory diagram showing calculation of an optimal training time shown in FIG.

FIG. 6 is a memory configuration diagram of a shortened procedure registration memory.

FIG. 7 is a flowchart showing a control operation at the time of transmitting and calling according to the example of the present invention.

FIG. 8 is a flowchart showing a control operation when receiving and receiving a call according to the present embodiment.

FIG. 9 is a control signal diagram of a normal procedure when registering a shortened procedure.

FIG. 10 is a control signal diagram during the shortening procedure.

FIG. 11 is a flowchart showing a control operation when the telephone number notification service is used.

FIG. 12 is a control signal diagram when the telephone number notification service is used.

FIG. 13 is a conventional control signal diagram.

[Explanation of symbols]

101 Reader 102 recording section 103 control unit 104 modem 104a Digital signal processing unit (DSP) 104b Analog front end (AFE) 105 line controller 106 lines 201 Modem control unit 202 Tonal transmitter 203 Tonal detector 204 V. 21 modem 205 INFO modem 206 control channel modem 207 Main channel modem 208 Line probing transmitter 209 Line probing receiver 210 Training Transmitter 211 Training receiver 401 demodulator 402 Adaptive equalizer 403 Judgment unit 405 Absolute value instrument 406 Low Pass Fill 407 Equalization capability analysis section

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-191613 (JP, A) JP-A-6-164879 (JP, A) JP-A-5-219334 (JP, A) JP-A-3- 154566 (JP, A) JP-A-9-312749 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 1/32-1/36 H04N 1/42-1/44

Claims (2)

(57) [Claims] 1. A sender that sends an identification signal in response to an incoming call.
And during the sending of the identification signal, the calling party performs a shortening procedure.
Detection means for detecting a signal indicating or a signal indicating a normal procedure
And information about line characteristics or optimal training time
And a detecting means for storing the shortening procedure.
When the signal is detected, the information stored in the storage means
Omitting transmission of line probing signals based on
A data communication device comprising: communication means for performing communication according to a procedure . 2. A facsimile device comprising a scanner for reading a document, a printer for printing received data, and the data communication device according to claim 1 .