JPH09261360A - Data communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide data communication equipment with which an optimum transmission line can be corrected corresponding to the destination of a communicating party. SOLUTION: This equipment has a register circuit 24 for registering information for fixedly correcting the transmission line corresponding to the transmission party and at the time of communication execution, communication is executed based on the information, which is reported by the procedure signal of opposite side equipment, for correcting the variable transmission line. Further, by updating the information, which is registered in the register circuit 24, for fixedly correcting the transmission line based on the reported information for correcting the variable transmission line, a fixed equalizer can be inserted almost at the intermediate part of a dynamic range, with which the characteristics of the transmission line can be automatically corrected, between the equipment corresponding to the destination of each transmission party and high-reliability communication is enabled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data communication apparatus such as a facsimile apparatus having a means for fixedly correcting a transmission line.

[0002]

2. Description of the Related Art In a conventional facsimile machine, the high frequency loss becomes large due to the f ^1/2 characteristic of the subscriber line from the facsimile machine to the telephone office (terminal station). Then, this loss amount increases substantially in proportion to the length of the subscriber line. Therefore, in order to correct this, the facsimile apparatus has a fixed amplitude equalizer of 1.8 Km, as shown in FIG.
It was possible to set 3.6km and 7.2km.

[0003]

However, in the above-mentioned conventional example, the fixed amplitude equalizer is always fixed to the communication partner, and once set, it cannot be changed until it is set again by the serviceman. For this reason, there is a drawback that it is not possible to deal with the case where the position of the exchange (terminal station) is changed or the place where the facsimile is installed is changed.

Further, it is necessary to determine the value of the fixed amplitude equalizer each time it is installed, which is very complicated.

It is an object of the present invention to provide a data communication device capable of optimally correcting a transmission line according to a communication partner.

[0006]

Means for Solving the Problems The first invention of the present application is:
It has a registration means for registering information for fixedly correcting the transmission path corresponding to the transmission partner, and when communication is executed, communication is performed based on the information for correcting the variable transmission path notified by the procedure signal of the partner device. Then, based on the notified information for correcting the variable transmission path, the information for fixedly correcting the transmission path registered in the registration means is updated. Correspondingly, the fixed equalizer can be inserted between the devices at the middle of the dynamic range where the characteristics of the transmission path can be automatically corrected, and highly reliable communication becomes possible.

The second invention of the present application is such that information for fixedly correcting the transmission path is registered based on the pre-emphasis information designated by the receiver.
In the third invention of the present application, if the pre-emphasis designated by the receiver is a designation for correcting the high frequency band of the frequency component, this time, in contrast to the information for fixedly correcting the currently registered transmission path, The specified correction amount is fed back and registered in the registration means as a correction value. Further, according to the fourth invention of the present application, when the pre-emphasis designated by the receiver is continuously uncorrected for a predetermined number of times, information for fixedly correcting the currently registered transmission path is provided. On the other hand, the amount of correction in the high frequency band is reduced by a predetermined amount and registration is made in the registration means. From the above, V. In H.34 communication, it is possible to correct the optimum transmission path, and it is possible to perform highly reliable communication.

[0008]

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

The NCU (network control unit) 2 is connected to a terminal of the line in order to use the telephone network for data communication and the like,
It controls connection of a telephone exchange network, switches to a data communication path, and holds a loop. The NCU 2 connects the telephone line 2a to the telephone 4 when the signal level (signal line 20a) from the control circuit 20 is “0”, and connects the telephone line 2a when the signal level is “1”. It is connected to the facsimile machine side.
In a normal state, the telephone line 2a is connected to the telephone 4 side.

The hybrid circuit 6 separates the transmission system signal and the reception system signal, sends the transmission signal from the fixed amplitude correction circuit 22 to the telephone line 2a via the NCU2, and the signal from the other side to the NCU2. It is received via the signal line and sent to the modulator / demodulator 8 via the signal line 6.

The modulator / demodulator 8 complies with ITU-T Recommendation V.6. 8,
V. 21, V.I. 27 ter, V.I. 29, V.I. 17, V.I.
34, and performs modulation and demodulation based on
Each transmission mode is designated by the signal line 20c. The modulator / demodulator 8 receives a signal output on a signal line 20b, outputs modulated data on a signal line 8a, receives a received signal output on a signal line 6a, and outputs demodulated data on a signal line 8b. Output.

The ANSam transmission circuit 10 is a circuit for transmitting the ANSam signal. When the signal of the signal level "1" is output to the signal line 20b, the ANSam signal is transmitted to the signal line 10a and the signal line 20d. When the signal of the signal level "0" is output to the signal, no signal is output to the signal 10a.

The adder circuit 12 inputs the information of the signal line 8a and the information of the signal line 10a, and adds the result of addition.
a. The reading circuit 14 reads an image of a document and outputs the read image data to a signal line 14a. The recording circuit 16 is for sequentially recording information output to the signal line 20e line by line.

The memory circuit 18 is used for storing raw information of read data or coded information, and for storing received information, decoded information or the like.

The fixed amplitude correction circuit 22 inputs the information output to the signal line 12a, performs the correction specified on the signal line 20f, and outputs the corrected information to the signal line 22a. Here, as elements that can be corrected, in addition to the corrections of 1.8 Km, 3.6 Km, and 7.2 Km shown in FIG. 2, there are corrections of indexes 1 to 10 shown in FIGS. There is. It should be noted that the correction values shown in FIG.
The correction values shown in FIG. 6 can be added.

The registration circuit 24 is connected via a signal line 24a.
This is a circuit for registering information of a fixed amplitude equalizer corresponding to each destination. Here, 01 to 24 of one-touch dial
Assuming the above, the correction of 3.6 Km is registered as the default value corresponding to these. The number of times the pre-emphasis amplitude correction is not required, which corresponds to 01 to 24 of the one-touch dial, that is,
Pre-emphasis filter index is consecutive 0
Has a counter that counts the number of times specified.

The operation unit 26 has a one-touch dial, a speed dial, a set key, a ten-key pad, a start key, a one-touch dial, a key necessary for registering a speed dial, and other function keys, and the pressed key information is a signal. Output on line 26a.

The control circuit 20 controls the entire facsimile apparatus. In particular, in the present embodiment, the control circuit 20 is based on the information for correcting the variable transmission line notified by the procedure signal from the partner at the time of executing communication. , The registration circuit 24
The processing for changing the information for fixedly correcting the transmission path registered in is performed. Here, the transmitter registers information for fixedly correcting the transmission path based on the pre-emphasis information designated by the receiver.

More specifically, if the pre-emphasis designated by the receiver is a designation for correcting the high frequency range of the frequency component, the transmitter uses information for fixedly correcting the currently registered transmission path. On the other hand, the predetermined amount of the correction amount designated this time is registered in the registration circuit 24 as a feedback correction value. Also, the transmitter does not correct the pre-emphasis specified by the receiver, that is, the index is 0.
If a predetermined number of times occurs, for example, three times in succession, the high-frequency correction amount is reduced by a predetermined amount with respect to the information for fixedly correcting the currently registered transmission path, and the registration circuit 24 is notified. I will register.

7 to 11 are flowcharts showing the control flow of the control circuit 20 in this embodiment.

First, in S32, all 3.6 Km as a fixed amplitude correction amount is registered in the one-touch dials 01 to 24 in the registration circuit 24 through the signal line 24a, and the index 0 designated by the pre-emphasis is consecutively counted. Register 0. In addition, the pre-emphasis correction amount (see FIG.
6) is set to index 0.

In S34, a signal of signal level "0" is output to the signal line 20a to turn off the CML, and in S36,
The signal of the signal level "0" is output to the signal line 20d, and AN
Does not send Sam signal.

In S38, it is determined whether or not a call is selected. If a call is selected, the process proceeds to S42. If no call is selected, the process proceeds to S40 and other processes are performed.

In S42, the fixed amplitude correction information registered in the registration circuit 24 in correspondence with the designated one-touch dial, specifically, the correction Km of the subscriber line cable shown in FIG. 3 to 6 outputs the correction obtained by adding the two corrections indicated by the pre-emphasis indexes 1 to 10 to the signal line 20f, and the fixed amplitude correction circuit 22.
Realized by.

Next, in S44, a call is made to the designated destination. Then, in S46, the signal of the signal level "1" is output to the signal line 20a to turn on the CML.

In S48, the V. It is determined whether or not the ANSam signal of No. 8 is detected, and if it is detected, the process proceeds to S60, and if not detected, the process proceeds to S52.

In S52, the V. 21 NSF / CSI /
It is determined whether or not the DIS signal has been received, and if received, S5
If not received, go to S54.

In S54, it is determined whether or not the T1 timer has timed out. If the time has expired, the process proceeds to S34, and if not, the process proceeds to S50.

In step S56, the receiver of the other party receives the V. It is determined whether there is a communication function of V.34.
If there is no communication function of V.34, the process proceeds to S68, and V.34. 21 pre-procedure, V.21. 27 ter, V.I. 29, V.I. 17 image transmission (S70), V.17. The post-procedure 21 (S72) is performed.

In addition, V. If there is a communication function of 34, S5
Proceed to V.8. The CI signal of No. 8 is transmitted and it progresses to S60.
In S60, the V. No. 8 CM signal is transmitted, JM signal is received, and CJ signal is transmitted.

Next, in step S62, line-proping is transmitted, and in step S64, INFOh is received. This makes it possible to determine the pre-emphasis information.

FIG. 12 is an explanatory diagram showing the contents of INFOh. Here, from INFOh bit23 to bit2
6 specifies the index of the pre-emphasis filter.

In S66, it is judged whether or not the designation of the pre-emphasis index is 0, and if it is 0, S7
If it is not 0, that is, if it is any of 1 to 10, the process proceeds to S94.

In S74, the value of the number of consecutive times that the index designated by the pre-emphasis corresponding to the one-touch dial that has been called is 0 is incremented by 1 and registered in the registration circuit 24.

At S76, the remaining V. 34, and in S78, V. 34 image transmission is performed. Furthermore, S
In 80, V. 34 post-procedure.

In S82, a signal of signal level "0" is output to the signal line 20a to turn off CML.

In S84, the value of the number of consecutive times of the index 0 incremented in S74 is 3 or more, that is,
It is judged from the same receiver that it is continuously notified that 3 communications and pre-emphasis are not designated. If it is 3 or more, the process proceeds to S86. If it is less than 3, the process proceeds to S34.

At S86, the current setting of the fixed equalizer is made by judging whether or not the correction of any of indexes 1 to 10 shown in FIGS. 3 to 6 is used as the fixed equalizer. To S92, and to S88 if not.

S88 corresponds to the destination with which communication has been made up to now, and if the current correction of the fixed equalizer is 7.2 Km, 3.6.
Km, similarly, if 3.6Km, 1.8Km, 1.8K
If m, the correction amount is reduced by 1 to 0 Km, and the circuit 24
Register with.

In S90, the index designated by the pre-emphasis corresponding to the destination communicated up to now is 0.
The value of the number of consecutive times of the number of times is 0 is registered in the registration circuit 24.

In S92, if the index is 10, the fixed amplitude correction value corresponding to the pre-emphasis corresponds to the destination communicated up to now, and if the index is 10, the index 9 is entered.
Similarly, if index 9 is index 8, index 8 is index 7, index 7 is index 6, index 6 is index 0
(Not index 5), index 5 to index 4, index 4 to index 3,
If index 3, go to index 2, index 2
If so, the index 1 is registered, and if the index 1 is registered, the index 0 is registered in the registration circuit 24.

Further, in S94, it is assumed that XKm, index Y and the registration circuit 24 are registered as fixed amplitude correction amounts corresponding to the destinations which have been communicated up to now. If the current designation is pre-emphasis indexes 1, 2, 3, 4, and 5, the index Y is 0.
5 to 5, the new indexes Y are Y + 1, Y + 1, Y + 1, Y + 2, Y, respectively.
Assuming +2, if the value of this index exceeds 5, the subscriber line cable length is set to 5, and if 0, it is 1.8 Km, and if 1.8 Km, 3.6 Km and 3.6 Km.
If so, increase to 7.2 km. If the current value is 7.2 Km, it is left as it is.

Similarly, if the designations this time are pre-emphasis indexes 6, 7, 8, 9, and 10, if the indexes are included in 0, 6 and 10, respectively, in order.
Y + 1, Y + 1, Y + as new index Y
Assuming 1, Y + 2, Y + 2 (additional 5 is added if the current index is Y = 0), if the index value exceeds 10, it is set to 10, and if the subscriber line cable length is 0, 1. 8km, 1.8km 3.6
If Km or 3.6 Km, increase to 7.2 Km. If the current value is 7.2 Km, it is left as it is. Then, these are registered in the registration circuit 24 as the values of the fixed amplitude correction after the next time.

If the designation of the index by the pre-emphasis this time is 1, 2, 3, 4, 5 and the index Y is 6, 7, 8, 9, 10 respectively, it is currently registered. Index Y is 1, 2, 3, 4,
If the index designation by pre-emphasis this time is 6, 7, 8, 9, 10 and the index Y is 1, 2, 3, 4, 5, then each is registered as current. The index Y is 6, 7, 8,
Judge as 9, 10 and perform the above control.

Next, in S96, the modulator / demodulator 8 corrects the pre-emphasis index that has just been designated. Next, in S98, the V. 34, and S1
00, V. 34 image transmission is performed. Further, S102
Then, V. The post-procedure of S34 is performed, and the process proceeds to S34.

[0046]

As described above, according to the first invention of the present application, it becomes possible to automatically correct the characteristics of the transmission line between the devices corresponding to each transmission destination, and the reliability is improved. This has the effect of enabling high communication.

According to the second to fourth inventions of the present application, V.
In the H.34 communication, it is possible to optimally correct the transmission path, and it is possible to perform highly reliable communication.

[Brief description of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is an explanatory diagram showing amplitude correction characteristics of a subscriber line cable.

FIG. 3 is an explanatory diagram showing an amplitude correction characteristic by pre-emphasis.

FIG. 4 is an explanatory diagram showing amplitude correction characteristics by pre-emphasis.

FIG. 5 is an explanatory diagram showing amplitude correction characteristics by pre-emphasis.

FIG. 6 is an explanatory diagram showing an amplitude correction characteristic by pre-emphasis.

FIG. 7 is a flowchart showing the operation of the embodiment.

FIG. 8 is a flowchart showing the operation of the above embodiment.

FIG. 9 is a flowchart showing the operation of the embodiment.

FIG. 10 is a flowchart showing the operation of the embodiment.

FIG. 11 is a flowchart showing the operation of the above embodiment.

FIG. It is explanatory drawing which shows the content of INFOh in 34.

[Explanation of symbols]

 2 ... NCU, 4 ... Telephone, 6 ... Hybrid circuit, 8 ... Modulator / demodulator, 10 ... ANSam sending circuit, 12 ... Adder circuit, 14 ... Read circuit, 16 ... Recording circuit, 18 ... Memory circuit, 20 ... Control circuit, 22 ... fixed amplitude correction circuit, 24 ... registration circuit, 26 ... operation unit.

Claims (4)

[Claims] 1. A registration means for registering information for fixedly correcting a transmission line corresponding to a transmission partner, and correcting a variable transmission line notified by a procedure signal of a partner device when communication is executed. The communication is executed based on the information, and further, the information for fixedly correcting the transmission path registered in the registration means is updated based on the notified information for correcting the variable transmission path. Data communication device. 2. The data communication device according to claim 1, wherein information for fixedly correcting the transmission path is registered based on the pre-emphasis information designated by the receiver. 3. The pre-emphasis specified by the receiver according to claim 2, when the pre-emphasis is specified to correct the high frequency range of the frequency component, the information for fixedly correcting the currently registered transmission path A data communication device, characterized in that a predetermined correction amount specified this time is fed back to be registered as a correction value in the registration means. 4. The information according to claim 2, wherein the pre-emphasis designated by the receiver is a correction for a currently registered transmission line when the correction-free pre-emphasis occurs a predetermined number of times in a row. A data communication device, characterized in that the amount of correction in a high frequency band is reduced by a predetermined amount and registration is performed in the registration means.