JPH10107995A - Facsimile equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly conduct control of a signal transmission level and correction of a frequency characteristic or the like in both the cases that the facsimile equipment is in use in connection to an analog telephone line and the facsimile equipment is used in connection to an ISDN line through the use of a terminal adaptor. SOLUTION: Depending on the result of selection by a selection button 22 that selects the connection of the facsimile equipment to an analog telephone line or to an ISDN line through the use of a terminal adaptor, in the case that the facsimile equipment is connected to an ISDN line through the use of a terminal adaptor, the transmission level of signals is made constant and the signals are sent without correcting amplitude of the signals at signal transmission, and in the case that the facsimile equipment is connected to an analog telephone line, the transmission level of signals is set variable and the amplitude of the signals is corrected at signal transmission.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus which can be connected to a plurality of types of lines.

[0002]

2. Description of the Related Art Recently, a DSU using an ISDN line has been proposed.
(Data service units) and G3 facsimile machines connected via TAs (terminal adapters) are increasingly used for communication.

[0003] However, with respect to such diversification of usage, the G3 facsimile apparatus has exactly the same control regardless of whether it is connected to an analog line or to an ISDN line via a terminal adapter. Had gone.

[0004]

As a G3 facsimile apparatus accommodating two types of lines, for example,
In Japanese Patent Application No. Hei 7-335827, a return communication is performed between two lines, and an ATT value (a value for determining a signal transmission level) and an NL value (a value for correcting a frequency characteristic of a subscriber line) are determined. A configuration that automatically determines the position has been proposed.

Therefore, in such a configuration, a user using an analog telephone line needs two lines, switches to an ISDN line, purchases a terminal adapter, and connects the telephone with the G3 facsimile apparatus used up to now. Think that you connected. Here, the distance from this place to the exchange is long, for example, the correction of NL is 7.2k.
m, and the transmission level is assumed to be transmitted at -3 dBm.

However, in such a case, since the distance between the facsimile apparatus and the terminal adapter is short and there is no loss, the signal transmission level does not decrease, and the terminal adapter is clamped beyond the dynamic range of the terminal adapter. was there.

The correction of NL is based on the f1 ^{/ 2} characteristic of the subscriber line cable (if the frequency f increases, f1 ^{/ 2}
And the loss increases). Here, since the A / D conversion is immediately performed by the terminal adapter, there is no increase in loss due to the f ^1/2 characteristic of the subscriber line cable.
Performing the NL correction has the disadvantage of over-equalization, distortion of the waveform, and communication errors.

According to the present invention, the control of the signal transmission level and the correction of the frequency characteristics are properly performed between the case where the terminal is connected to an analog telephone line and the case where the terminal is connected to an ISDN line using a terminal adapter. It is an object of the present invention to provide a facsimile apparatus that can perform the operation.

[0009]

Means for Solving the Problems The first invention of the present application is:
A facsimile apparatus which can be connected to an analog telephone line and which can be connected to an ISDN line by using a terminal adapter.
It has a selection means for selecting whether or not it is connected to the SDN line, and the control at the time of executing the G3 facsimile communication is changed according to the selection result of the selection means. Also,
The second invention of the present application uses a terminal adapter to provide I
When connected to an SDN line, the signal transmission level is kept constant. Further, the signal is transmitted without correcting the amplitude at the time of signal transmission. When the terminal is connected to an analog telephone line, the signal transmission level is set. And the signal is transmitted with the amplitude correction at the time of signal transmission being effective.

Thus, when transmitting to the ISDN line using the terminal adapter, the signal can be transmitted so as to match the dynamic range of the input side of the terminal adapter, and the signal transmission level with respect to the frequency characteristic can be flattened. It becomes possible to communicate.

A third invention of the present application is a facsimile apparatus that can be connected to an analog telephone line and can be connected to an ISDN line by using a terminal adapter. Using two lines, we conducted a test of terminal loopback and found no transmission loss.
If the loss with respect to the frequency is constant, it is determined that the terminal is connected to the ISDN line using the terminal adapter. If there is a transmission loss and if the loss with respect to the frequency is not constant, the terminal is connected to the analog telephone line. Is determined.

Thus, it is possible to automatically determine whether two lines are accommodated and connected to an analog line or connected to an ISDN line via a terminal adapter.
Further, based on this determination result, the first and second
It becomes possible to perform the control according to the invention of (1).

[0013]

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

An NCU (network control unit) 2 connects 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 addition circuit 12 to the telephone line 2a via the NCU 2, and transmits the signal from the other party via the NCU 2. The signal is received and sent to the modem 8 via the signal line 6a.

The modulator / demodulator 8 is based on ITU-T Recommendation V. 8,
V. 21, V.I. 27ter, 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 sending circuit 10 is a circuit for sending an ANSam signal. When a signal of signal level "1" is output to the signal line 20d, the ANSam sending circuit 10 sends an ANSam signal to the signal line 10a and sends it to the signal line 20d. When the signal of the signal level “0” is being output, no signal is output to the signal line 10a.

The addition circuit 12 inputs the information of the signal line 8a and the information of the signal line 10a, and adds the result of the addition to the signal line 12a.
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 encoded information, and also for storing received information or decoded information.

The selection button 22 is connected to an analog line or connected to an ISD through a terminal adapter (TA).
N is a button for selecting whether or not the connection is made to N. When this button 22 is pressed, a pressing pulse is generated on the signal line 22a.

The display circuit 24 is connected to an analog line or is connected to an ISDN via a terminal adapter (TA).
This is a circuit for displaying the selection status as to whether or not a connection is made. When a clear pulse is generated on the signal line 20f, "connection to an analog line" is displayed. Connect to ISDN line via TA "→" Connect to analog line "→" ISD via TA
"Connect to N line" is displayed.

When the display circuit 24 indicates "Connect to analog line", the display circuit 24 outputs a signal of signal level "0" to the signal line 24a, and outputs "ISDN via TA".
"Connect to line" is displayed on the signal line 24a.
A signal of signal level "1" is output.

The transmission level setting circuit 26 is a circuit for setting a transmission level, from 0 dBm to -15 dBm.
It can be set in 1 dB steps. Then, the information of the set transmission level is output to the signal line 26a.

The NL correction circuit 28 is a circuit for correcting NL (subscriber line cable), and is 1.8 km, 3.6 km.
The correction of the subscriber line cable corresponding to m, 5.4 km, and 7.2 km can be set, and the set information is output to the signal line 28a.

The control circuit 20 controls the entire facsimile apparatus. In particular, in the present embodiment, the control circuit 20 performs a process of changing the control for executing the G3 facsimile communication according to the selection result of the selection button 22. It is.

Specifically, when the terminal is connected to the ISDN line using a terminal adapter, the signal transmission level is kept constant, and the signal is transmitted without correcting the amplitude at the time of signal transmission. When connected to a telephone line, the signal transmission level is made variable by setting, and the amplitude correction at the time of signal transmission is made valid.

FIGS. 2 to 4 are flowcharts showing the control flow of the control circuit 20.

First, the operation is started in S0, and in S2, a clear pulse is generated on the signal line 20f, and the display circuit 24 displays that the connection of the analog line is selected.

Next, in S4, a signal of signal level "0" is output to the signal line 20a to turn off the CML, and in S6,
A signal having a signal level “0” is output to the signal line 20 d and
The state where the Sam signal is not transmitted is set.

Next, in S8 and S10, it is determined whether facsimile transmission or facsimile reception is selected. If facsimile transmission is selected, the process proceeds to S14. If facsimile reception is selected, the process proceeds to S32. If neither is selected, the process proceeds to S12, executes other processing, and returns to S4.

In step S14, it is determined whether the information on the signal line 24a is input and the display for selecting the connection of the analog line or the display for selecting the connection of the ISDN line via the terminal adapter is made. If it is displayed to select the connection of the analog line, the process proceeds to S16, and if it is displayed to select the connection of the ISDN line via the terminal adapter, the process proceeds to S20.

In step S16, information on the signal line 26a is input, and the set transmission level is set in the modem 8 via the signal line 20c. Next, in S18, the information of the signal line 28a is input, and the set NL correction value is input to the signal line 20a.
Set to the modem 8 via c. Thereafter, the process proceeds to S24.

At S20, the transmission / reception level of -8 dBm is set to the modem 8 via the signal line 20c. Next, in S22, the NL value is set to 0 km in the modem 8 via the signal line 20c. That is,
Since it does not pass through the subscriber line cable as an analog signal, it is not corrected. Thereafter, the process proceeds to S24.

With the settings of S20 and S22,
The transmission level of all signals is 4.4 Vpeak to
Since the signal does not exceed the peak and falls within the dynamic range of the terminal adapter, communication can be reliably performed.

Next, at S24, a signal of signal level "1" is output to the signal line 20a to turn on the CML, and the pre-procedure is performed at S26, the image signal is transmitted at S28, and the post-procedure is performed at S30.

In step S32, it is determined whether or not the information on the signal line 24a is input and the display for selecting the connection of the analog line or the display for selecting the connection of the ISDN line via the terminal adapter is displayed. If it is determined that the display for selecting the connection of the analog line is displayed, the process proceeds to S34, and if the display for selecting the connection of the ISDN line via the terminal adapter is displayed, the process proceeds to S38.

In S34, the information of the signal line 26a is input, and the set transmission level is set to the modem 8 via the signal line 20c. Next, in S36, the information of the signal line 28a is input, and the set NL correction value is input to the signal line 20a.
Set to the modem 8 via c. Thereafter, the process proceeds to S42.

At S38, the modem 8 is set to the transmission level of -8 dBm via the signal line 20c. Then, in S40, the modem 8 is set to set the NL value to 0 km via the signal line 20c. That is, since the signal does not pass through the subscriber line cable as an analog signal, it is not corrected. Thereafter, the process proceeds to S42.

With the settings of S38 and S40,
The transmission level of all signals is 4.4 Vpeak to
Since the signal does not exceed the peak and falls within the dynamic range of the terminal adapter, communication can be reliably performed.

Next, in S42, a signal of signal level "1" is output to the signal line 20a to turn on the CML. Then, the pre-procedure is executed in S44, the image signal is received in S46, and the post-procedure is executed in S48.

Next, a second embodiment of the present invention will be described.

In the second embodiment, the analog telephone line and the I
Perform a terminal loopback test using the SDN line,
If there is no transmission loss and the loss for frequency is constant,
It is determined that the terminal adapter is connected to the ISDN line using the terminal adapter. If there is a transmission loss and the loss with respect to the frequency is not constant, it is determined that the terminal is connected to an analog telephone line. Then, the control of FIGS. 2 to 4 of the first embodiment is executed.

FIG. 5 is a block diagram showing elements added to the respective elements of FIG. 1 of the first embodiment in the second embodiment. As shown, in this embodiment, the NCU 32,
Telephone 34, hybrid circuit 36, modem 38, A
An NSam sending circuit 40 and an adding circuit 42 are additionally provided. The individual functions are common to the NCU 2, the telephone 4, the hybrid circuit 6, the modem 8, the ANSam transmission circuit 10, and the addition circuit 12 in FIG.

Here, the NCU 2, telephone 4, hybrid circuit 6, modulator / demodulator 8, and adder circuit 12 shown in FIG. 1 are used as a communication unit A, and NCU 32, telephone 34, hybrid circuit 36, modulator / demodulator 38 shown in FIG. The circuit 42 will be described as a communication unit B.

FIGS. 6 and 7 are flow charts showing a part of the control of the control circuit 20 according to the present embodiment, which is different from FIGS. 2 to 4 of the first embodiment.

First, in FIG. 6, the operation is started in S50, and in S52, it is determined whether or not the line connection is registered. If the line connection is registered, the process proceeds to S68, and if the line connection is not registered. Proceed to S54.

In S54, the telephone line 2a is switched to the telephone line 3
2a, that is, from the communication unit A to the communication unit B,
Make a call connection. That is, both the communication unit A and the communication unit B
Turn L on.

In S56, the communication between the communication unit A and the communication unit B In step S58, a line probing signal is transmitted from the communication unit A to the communication unit B, and the communication unit B receives the line probing signal.

In S60, based on the reception result of the communication unit B,
The transmission loss is within 2 dB, ie, 300 Hz
It is determined whether or not the transmission loss calculated from the average energy up to 3400 Hz is within 2 dB. If it is within 2 dB, the process proceeds to S62, and if it exceeds 2 dB, the process proceeds to S66.

In S62, based on the reception result of the communication unit B,
It is determined whether the variation of the transmission loss for each frequency is also within 2 dB, and when it is within 2 dB, the process proceeds to S64,
If it exceeds 2 dB, the process proceeds to S66.

In S64, I is transmitted via the terminal adapter.
It is determined that it is connected to the SDN line and registered, and the process proceeds to S68. On the other hand, in S66, it is determined that the connection is made to the analog line and registered, and the process proceeds to S68.

In S68, it is determined whether or not communication in the communication section A is being selected or being executed.
The process advances to S70, and if the answer is negative, the process advances to S72.

In S70, S8 to S48 are executed for a predetermined time (for example, 300 μs). Here, S14, S3
The determination of 2 is made based on the registration of S64 and S66.

In S72, it is determined whether or not communication in the communication section B is selected or being executed. If the response is an affirmative response, the process proceeds to S74. If the response is a negative response, the process proceeds to S68.

In step S74, steps S8 to S48 are executed in block 32.
From block 42 to a predetermined time (for example, 300
μs) indicates execution. Here, S14, S
The judgment of No. 32 is made based on the registration of S64 and S66.

[0056]

As described above, according to the first and second aspects of the present invention, the ISD is provided by using the terminal adapter.
When transmitting to the N line, a signal can be transmitted so as to match the dynamic range of the input side of the terminal adapter, and the signal transmission level with respect to the frequency characteristic can be made flat, so that reliable communication can be performed.

Further, according to the third aspect, it is possible to automatically determine whether two lines are accommodated and connected to an analog line or to an ISDN line via a terminal adapter. The control according to the first and second aspects of the invention can be performed based on the determination result, and a convenient device can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the first embodiment.

FIG. 3 is a flowchart showing the operation of the first embodiment.

FIG. 4 is a flowchart showing the operation of the first embodiment.

FIG. 5 is a block diagram showing a configuration added in a second embodiment of the present invention.

FIG. 6 is a flowchart showing an operation added in the second embodiment.

FIG. 7 is a flowchart showing an operation added in the second embodiment.

[Explanation of symbols]

 2, 32: NCU, 4, 34: Telephone, 6, 36: Hybrid circuit, 8, 38: Modulator / demodulator, 10, 40: ANSam transmission circuit, 12, 42: Addition circuit, 14: Reading circuit, 16: Recording circuit , 18 memory circuit, 20 control circuit, 22 selection button, 24 display circuit, 26 transmission level setting circuit, 28 NL correction circuit.

Claims (3)

[Claims] 1. A facsimile apparatus connectable to an analog telephone line and connectable to an ISDN line using a terminal adapter, wherein the facsimile apparatus is connected to an analog telephone line or an ISDN line is connected to a terminal adapter. A facsimile apparatus which has a selection unit for selecting whether or not the G3 facsimile communication is performed, according to a selection result of the selection unit. 2. The method according to claim 1, wherein when the terminal is connected to the ISDN line using a terminal adapter, the signal transmission level is kept constant, and further, the signal is transmitted without correcting the amplitude at the time of signal transmission. A facsimile apparatus characterized in that when connected to a telephone line, a signal transmission level is made variable by setting, and a signal is transmitted with amplitude correction at the time of signal transmission enabled. 3. A facsimile apparatus which can be connected to an analog telephone line and which can be connected to an ISDN line by using a terminal adapter.
A terminal loopback test is performed. If there is no transmission loss and the loss with respect to the frequency is constant, it is determined that the terminal adapter is connected to the ISDN line using the terminal adapter, and there is a transmission loss and the loss with respect to the frequency is constant. If not,
A facsimile apparatus characterized in that it is determined that it is connected to an analog telephone line.