JP2005123952A - Communication terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication terminal such as a facsimile machine capable of reducing communication errors when executing data communication such as image communication via an IP phone network. <P>SOLUTION: When detecting a call tone of an IP phone within a prescribed time (e.g., within 10 seconds) after a telephone number of an opposite party is dialed (YES in a step S7, and a step S8 shown in Figure), a main control section 1 of the facsimile machine 20 discriminates the call tone to be a call to the IP phone network and sets a high speed flag to an OFF state (step S21) so as to control a FAX MODEM 10 so that in this case (NO in step S12) a maximum symbol rate of the FAX MODEM 10 is set to 2,400 bauds and a maximum data speed of the FAX MODEM 10 is set to 9,600 bps (step S13). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a communication terminal apparatus that controls the maximum data rate or maximum symbol rate of a modem such as a facsimile apparatus.

  In the conventional G3 mode facsimile apparatus, training for transmitting and receiving test signals is performed before transmission of image data to determine communication conditions such as a data rate, and then transmission and reception of image data is performed.

  For example, in Patent Document 1, “one digit of a dial number indicated by a dial number signal to be sent to a line in a facsimile apparatus is used to prevent a malfunction such as a communication error from occurring by using the latest modulation method. It is determined whether or not the eye number matches a preset setting value (step S2 in FIG. 2 of Patent Document 1), and if they do not match (N in step S2), a fax is scanned using the V34 modulation method. Although it is transmitted (step S4), if they match (Y in step S2), the fax is transmitted after changing to the V17 modulation method (step S3). "

JP 2000-175011 A.

  In recent years, when performing facsimile image communication via an IP telephone network, there has been a problem that communication errors frequently occur when the modem data rate and symbol rate are high.

  An object of the present invention is to provide a communication terminal device such as a facsimile machine that can solve the above-described problems and reduce communication errors when data communication such as image communication is executed via an IP telephone network. It is in.

  The communication terminal device according to the present invention is a control means for controlling to reduce at least one of the maximum data rate and the maximum symbol rate of the modem when communicating by transmitting to the communication terminal device of the other party via the IP telephone network. It is provided with.

  In the above communication terminal device, whether or not the call was made to the other party's communication terminal device via the IP telephone network based on whether or not the IP phone ringing tone was detected within a predetermined time after dialing the other party's phone number It is further characterized by a determination means for determining whether or not.

  Further, in the communication terminal device, the control means does not mask and execute data communication based on the communication standard of V34 of ITU-T recommendation when transmitting to the other party communication terminal device via the IP telephone network. The modem is controlled to execute data communication based on the communication standard of V17 of ITU-T recommendation. Alternatively, in the communication terminal device, the control means sets the maximum data rate of the modem to 9600 bps when transmitting to the communication terminal device of the other party via the IP telephone network, or The modem is controlled to set the maximum symbol rate to 2400 baud.

  According to the communication terminal device of the present invention, when making a call to the communication terminal device of the other party via the IP telephone network, control is performed so as to reduce at least one of the maximum data rate and the maximum symbol rate of the modem. Therefore, it is possible to reduce the probability of occurrence of communication errors in data communication such as facsimile image communication, or to prevent communication errors, and to prevent unnecessary training procedures from being repeated (fallback). The time can be shortened and the increase in communication charges can be reduced.

  Embodiments according to the present invention will be described below with reference to the drawings.

<Embodiment>
FIG. 1 is a block diagram showing a configuration of a facsimile apparatus 20 having a modem control function based on a ringing tone of an IP telephone, which is an embodiment according to the present invention.

  When the main control unit 1 of the facsimile apparatus 20 of this embodiment detects the IP phone ringing tone within a predetermined time (for example, within 10 seconds) after dialing the telephone number of the other party (step S7 in FIG. 2). YES, and step S8) It is determined that the call originates to the IP telephone network and the high speed flag is set to OFF (step S21). At this time (NO in step S12), the maximum symbol rate of the fax modem 10 is set to 2400 baud. The fax modem 10 is controlled to set the maximum data rate of the fax modem 10 to 9600 bps (step S13).

  Here, the IP phone sound sent to the calling terminal within a predetermined time after dialing the other party's phone number is, for example, “pup” indicating a connection to the IP phone network. When connecting to the general telephone network instead of the IP telephone network, there is a case where there is no ringing tone for this IP telephone, or another ringing tone such as “puppup” may be transmitted.

  In FIG. 1, a facsimile apparatus 20 has a conventional facsimile communication function such as a G3 system and a modem control function based on a ringing tone of an IP telephone. The main control unit 1 is specifically composed of a CPU, and is connected to the following hardware units via the bus 13 to control them, and executes various software functions to be described later. The image reading unit 2 reads a document with a scanner using a CCD or the like, and outputs dot image data converted into black and white binary. The image recording unit 3 is an electrophotographic printer or the like, and prints out image data received from another facsimile apparatus by facsimile communication as a hard copy and records it. The display unit 4 is a display device such as a liquid crystal display device (LCD) or a CRT display, and displays the operation state of the facsimile device 20 and displays image data of a document to be transmitted and received image data. .

  The operation unit 5 includes character keys necessary for operating the facsimile apparatus 20, a dial keypad, a speed dial key, a one-touch dial key, various function keys, and the like. In addition, you may comprise so that a part or all of the various keys of this operation part 5 may be substituted by making the above-mentioned display part 4 into a touch panel system.

  The ROM 6 stores in advance various software programs that are necessary for the operation of the facsimile apparatus 20 and are executed by the main control unit 1. Here, the programs include at least the transmission processing program of FIG. The RAM 7 is configured by SRAM, flash memory, or the like, and is used as a working area for the main control unit 1 to store temporary data generated when the program is executed. When a flash memory is used as the RAM 7, the contents of the data are not lost even when the power is cut off due to a power failure, movement of the device, or the like. The image memory 8 is composed of a DRAM or the like, and stores image data to be transmitted or received image data. Note that the RAM 7 and the image memory 8 may be constituted by a hard disk memory.

  The fax modem 10 is a modem connected to the public telephone line L and having a function of a fax modem for normal facsimile communication. The fax modem 10 demodulates data of outgoing telephone number information received as an FSK signal and sends it to the main control unit 1. Output. An NCU (Network Control Unit) 11 is a hardware circuit that performs an operation of closing and opening a DC loop of an analog public telephone line L and having an automatic dial function. Is connected to the public telephone line L. Here, the NCU 11 detects the ID receiving terminal activation signal and the normal telephone call signal in the outgoing telephone number notification service, and transmits the primary response signal and the secondary response signal in the outgoing telephone number notification service as necessary. can do. The NCU 11 may be connected to a baseband transmission type digital line (for example, an ISDN line) via a predetermined terminal adapter and a DSU (Subscriber Line Termination Unit: Digital Service Unit).

  The facsimile apparatus 20 of the present embodiment configured as described above has a modem control function based on the ringing tone of an IP telephone in addition to a normal facsimile communication function such as the G3 system. In the facsimile communication function, the dot image data read by the image reading unit 2 is encoded by software in accordance with an encoding method such as MH, MR, or MMR defined by the standard for facsimile communication, and then the counterpart facsimile machine On the other hand, the encoded data received from the facsimile machine of the other party is also decoded into image data by software and output from the image recording unit 3 as a hard copy. The image memory 8 stores the image data as necessary, and conversely outputs the stored image data as necessary.

  Furthermore, a communication procedure in the V34 mode capable of data communication such as facsimile communication at high speed will be described. When data communication is performed with a communication terminal device such as a facsimile device, a modem device conforming to the communication procedure of the recommended V17 mode of the ITU-T (International Telecommunication Union-Telecommunication Standardization Sector), for example, is used. Then, it is performed according to the procedure defined in the recommendation T30, which is also a G3 standard facsimile communication procedure. In addition, an ultra-high speed communication procedure (hereinafter referred to as V34 mode communication procedure) with a maximum transmission rate of 33.6 kbps conforming to the recommendation V34 has been put into practical use. During communication execution, the receiving side can specify the communication speed according to the current line status, specifically S / N (signal-to-noise power ratio) and bandwidth. In this way, the communication speed is changed so that transmission is performed at the communication speed specified on the receiving side. When data communication is performed using the communication procedure in the V34 mode, the actual communication speed is determined by performing the pre-procedure in the same recommended V8 communication procedure.

  Here, the relationship between the data rate and the symbol rate when performing data communication in the V34 mode is shown in the following table.

[Table 1]
Relationship between data rate and symbol rate in V34 mode ―――――――――――――――――――――――――――――――――――
Data rate (bps) Symbol rate (symbols / second)
―――――――――――――――――――――――――――――――――――
2400 2400
4800 2400, 2800, 3000, 3200, 3429
7200 2400, 2800, 3000, 3200, 3429
9600 2400, 2800, 3000, 3200, 3429
12000 2400, 2800, 3000, 3200, 3429
14400 2400, 2800, 3000, 3200, 3429
16800 2400, 2800, 3000, 3200, 3429
19200 2400, 2800, 3000, 3200, 3429
21600 2400, 2800, 3000, 3200, 3429
24000 2800, 3000, 3200, 3429
26400 2800, 3000, 3200, 3429
28800 3000, 3200, 3429
31200 3200, 3429
33600 3429
―――――――――――――――――――――――――――――――――――

  Also, in the V17 mode of the ITU-T recommendation, the data rate and symbol rate are based on the communication result of the training signal between 14400 bps (symbol rate = 2400 symbols / second, etc.) to 2400 bps (symbol rate = 2400 symbols / second). It is determined.

  FIG. 2 is a flowchart showing the outgoing call processing according to the embodiment, which is executed by the main control unit 1 of the facsimile machine 20 of FIG.

  It is determined whether or not a call is made in step S1 of FIG. 2. If YES, the process proceeds to step S2, while if NO, the process returns to step S1. Next, in step S2, it is determined whether or not the same job is redial due to the previous communication being a communication error. If YES, the process proceeds to step S3. If NO, the process proceeds to step S5. Further, in step S3, it is determined whether or not the IP phone ringing tone detection flag has been set in the previous communication. If YES, the process proceeds to step S4. If NO, the process proceeds to step S5. In step S4, after setting the high speed flag to OFF, the process proceeds to step S5.

  In step S5, dial transmission processing for dialing the other party's telephone number is executed, and in step S6, a T1 timer is started. Then, in step S7, it is determined whether or not an IP telephone ringing tone has been detected. If YES, the process proceeds to step S8, whereas if NO, the process proceeds directly to step S9. In step S8, a ringing tone detection flag for the IP telephone is set, and in step S21, the high speed flag is set to OFF, and the process proceeds to step S9. In step S9, it is determined whether or not the 2100 Hz signal of the facsimile communication procedure has been detected. If YES, the process proceeds to step S12. If NO, the process proceeds to step S10. In step S10, it is determined whether or not the T1 timer has timed out. If YES, the process proceeds to step S11. If NO, the process returns to step S7. In step S11, for example, a redial process to be executed after 3 seconds is set, and then the process returns to step S1.

  In step S12, it is determined whether or not the high speed flag is on. If YES, the process proceeds to step S14. If NO, the process proceeds to step S13. In step S13, the maximum symbol rate is set to 2400 baud and the maximum data rate is set to 9600 bps. Then, the process proceeds to step S15. In step S14, the maximum symbol rate is set to 3429 baud and the maximum data communication speed is set to 33.6 kbps. Then, the process proceeds to step S15. In step S15, facsimile transmission processing is executed. In the first process of the facsimile transmission process, the training process is executed based on the set maximum symbol rate and the maximum data rate, and the symbol rate and data rate of the fax modem 10 that is actually executed based on the training signal. To transmit / receive image data. Further, after the line is released in step S16, the process returns to step S1.

  As described above, when the main control unit 1 of the facsimile apparatus 20 detects the IP phone ringing tone within a predetermined time (for example, within 10 seconds) after dialing the other party's telephone number (see FIG. 2). YES in step S7 and step S8) It is determined that the call originates on the IP telephone network, and the high speed flag is set to OFF (step S21). At this time (NO in step S12), the maximum symbol rate of the fax modem 10 is set to 2400 baud. And the fax modem 10 is controlled to set the maximum data rate of the fax modem 10 to 9600 bps (step S13). Therefore, it is possible to reduce the probability of occurrence of communication errors in data communication such as facsimile image communication, or to prevent communication errors, and to prevent unnecessary training procedures from being repeated (fallback). The time can be shortened and the increase in communication charges can be reduced.

<Modification>
In the above embodiment, an example of the facsimile apparatus 20 is described. However, the present invention is not limited to this, and for example, a telephone connected to a public network such as an IP telephone network, a public telephone network, or a public digital circuit network, The present invention can be applied to communication terminal devices including data communication devices.

  In the above embodiment, the maximum symbol rate is set to 2400 baud and the maximum data rate is set to 9600 bps in step S13. In step S14, the maximum symbol rate is set to 3429 baud, and the maximum data communication speed is set to 33.6 kbps. The present invention is not limited to this, and in step S13, the data communication based on the communication standard of ITU-T recommendation V34 is not masked and executed, and the data communication is executed based on the communication standard of ITU-T recommendation V17. The fax modem 10 may be controlled as described above, and the fax modem 10 may be controlled to execute data communication in the V34 mode in step S14 (hereinafter referred to as a modified example). The present invention is not limited to the embodiment of FIG. 2 and its modifications, and may be controlled to reduce at least one of the maximum data rate and the maximum symbol rate of the fax modem 10.

1 is a block diagram showing a configuration of a facsimile machine 20 having a modem control function based on a ringing tone of an IP telephone, which is an embodiment according to the present invention. It is a flowchart which shows the transmission process which concerns on embodiment performed by the main control part 1 of the facsimile apparatus 20 of FIG.

Explanation of symbols

1 ... main control part,
2. Image reading unit,
3 ... image recording unit,
4 ... display part,
5 ... operation part,
6 ... ROM,
7 ... RAM,
8 ... Image memory,
10. Fax modem,
11 ... NCU,
13 ... Bus
20 ... facsimile machine,
L: Public telephone line.

Claims (4)

  Communication comprising control means for controlling to reduce at least one of a maximum data rate and a maximum symbol rate of a modem when communicating by transmitting to a communication terminal device of the other party via an IP telephone network Terminal device.   Judgment means for judging whether or not a call is transmitted to the communication terminal device of the other party via the IP telephone network based on whether or not the ringing tone of the IP telephone is detected within a predetermined time after dialing the other party's telephone number The communication terminal apparatus according to claim 1, further comprising:   The control means does not mask and execute data communication based on the communication standard of ITU-T recommendation V34 when making a call to the communication terminal device of the other party via the IP telephone network, and communication of V17 of ITU-T recommendation. The communication terminal apparatus according to claim 1, wherein the modem is controlled to execute data communication based on a standard. The control means sets the maximum data rate of the modem to 9600 bps or sets the maximum symbol rate of the modem to 2400 baud when making a call to the other communication terminal device via the IP telephone network. The communication terminal device according to claim 1, wherein the communication terminal device is controlled.

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