JP2007300336A - Communication terminal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication terminal device, such as a facsimile machine, securely continuing a facsimile reception procedure. <P>SOLUTION: The facsimile machine 20 includes an NCU 11 and a facsimile modem 10 which receive image data from an opposite-side facsimile machine by facsimile. When detecting an error line in the facsimile-received image data or detecting a carrier signal being interrupted for longer than a predetermined time, a main control unit 1 judges whether a frequency component of an FSK signal is detected, and performs control to receive a post message of the image data when detecting a frequency component of the FSK signal. Here, the main control unit 1 performs control to interrupt the detection of the frequency component of the FSK signal when no error line is detected in the facsimile-received image data and interruption of the carrier signal for longer than the predetermined time is not detected. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a communication terminal apparatus such as a facsimile apparatus.

  In Patent Document 1, even when image data is transmitted by ECM communication and synchronization is lost due to noise mixing during transmission of image data by high-speed modem mode, the normal transmission sequence can be restored by FSK mode. A conventional image data transmission processing method is disclosed. In the image data transmission processing method of Patent Document 1, when the image data for each block composed of a plurality of frames is being received in the high-speed modem mode, if synchronization is lost due to the inability to receive the synchronization flag included in the frame, forced After switching to the FSK mode and waiting for reception, when a transmission confirmation request signal transmitted by the FSK mode is received at the end of one block of image data from the transmission side, a retransmission request signal is sent to the transmission side. Request retransmission of the frame that could not be received correctly.

JP-A-4-345364.

  However, the conventional image data transmission processing method has a problem that the facsimile reception procedure cannot be reliably continued.

  An object of the present invention is to solve the above problems and provide a communication terminal apparatus such as a facsimile apparatus that reliably continues the facsimile reception procedure.

  According to a first aspect of the present invention, there is provided a facsimile apparatus for receiving image data from a counterpart communication terminal apparatus by facsimile, when an error line is detected in the received image data, or when a carrier signal is interrupted for a predetermined time or more. Control means for determining whether or not a predetermined frequency component of the facsimile procedure signal has been detected, and to control to receive a post message of image data when the predetermined frequency component is detected. It is provided with.

  In the communication terminal apparatus, the control means detects the predetermined frequency component when it does not detect an error line in the image data received by the facsimile and does not detect that the carrier signal has been interrupted for a predetermined time or longer. It is characterized by controlling to stop.

  Further, in the communication terminal device, the control means controls to stop detecting the predetermined frequency component when a signal indicating the end of each page of the image data is received. .

  Therefore, according to the communication terminal device of the present invention, when an error line is detected in image data received by facsimile or when it is detected that the carrier signal is interrupted for a predetermined time or more, a predetermined frequency component of the facsimile procedure signal is detected. By detecting this, it is possible to reduce erroneous detection of a predetermined frequency component in the image data and reliably continue the facsimile reception procedure, so that the reliability at the time of facsimile reception can be improved.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In addition, in each following embodiment, the same code | symbol is attached | subjected about the same component.

  FIG. 1 is a block diagram showing a configuration of a facsimile machine 20 according to an embodiment of the present invention. The facsimile machine 20 according to the present embodiment includes an NCU 11 and a fax modem 10 that receive image data from a facsimile machine of a partner, and the main control unit 1 detects an error line in the received image data. Alternatively, when it is detected that the carrier signal has been interrupted for a predetermined time or more, it is determined whether or not the frequency component of the FSK signal is detected. When the frequency component of the FSK signal is detected, a post message of image data is received. It is characterized by controlling to. Here, when the main control unit 1 does not detect an error line in the image data received by facsimile and does not detect that the carrier signal has been interrupted for a predetermined time or longer, the main control unit 1 stops detecting the frequency component of the FSK signal. Control. In addition, when receiving the RTC signal indicating the end of each page of the image data, the main control unit 1 performs control so as to stop detecting the frequency component of the FSK signal.

  In FIG. 1, a facsimile machine 20 includes a main control unit (CPU) 1, an image reading unit 2, an image recording unit 3, a display unit 4, an operation unit 5, a ROM 6, a RAM 7, and an image memory 8. , A fax modem 10 and an NCU (Network Control Unit) 11, and the components 1 to 11 are connected to each other via a bus 13. The NCU 11 is connected to a counterpart facsimile machine via a public telephone line L.

  The facsimile machine 20 has a facsimile communication function such as a conventional G3 system. Specifically, the main control unit 1 is composed of a CPU (Central Processing Unit) and is connected to the following hardware units via the bus 13 to control them, as well as various software described below. Perform the function.

  The image reading unit 2 reads an original with a scanner using a CCD or the like, and outputs dot image data changed to black and white. The image recording unit 3 is a printer apparatus such as an electrophotographic system, and prints out and records image data received from another facsimile apparatus by facsimile communication as a hard copy. The display unit 4 is a display device such as a liquid crystal display (LCD) or a CRT display, and displays the operation state of the facsimile device 20 and the image data of the original to be transmitted and the 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 are at least facsimile receptions of FIGS. 2 and 3 to be described later. Includes processing program. A RAM 7 (Random Access Memory) is configured by an SRAM (Static Random Access Memory), a flash memory, or the like, and is used as a working area of the main control unit 1 to store temporary data generated when a 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 includes a DRAM (Dynamic Random Access Memory) 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 that is connected to the public telephone line L via the NCU 11 and has a function of a fax modem for normal facsimile communication. The fax modem 10 receives outgoing telephone number information received as an FSK signal (frequency shift keying signal). Data is demodulated and output to the main control unit 1. The NCU 11 is a hardware circuit that performs closing and opening operations such as a DC loop of the analog public telephone line L and has an automatic dial function, and connects the fax modem 10 to the public telephone line L as necessary. 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 digital line of a baseband transmission system such as 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 normal facsimile communication function such as the G3 method. 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 in 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 converted into image data by software and output as a hard copy from the image recording unit 3. Note that the image memory 8 stores image data as necessary, and conversely outputs the stored image data as necessary.

  Furthermore, V.C. is capable of high-speed data communication such as facsimile communication. A 34-mode communication procedure will be described. When data communication is performed with a communication terminal device such as a facsimile machine, the recommendation V. of ITU-T (International Telecommunication Union-Telecommunication Standardization Sector) of the half duplex method, for example. The modem uses a modem that conforms to the 17-mode communication procedure, etc., and is a G3 standard facsimile communication procedure. Follow the procedure specified in 30. Also, the recommendation V.I. An ultra-high speed communication procedure (hereinafter referred to as a V.34 mode communication procedure) with a maximum transmission rate of 33.6 kbps conforming to the standard No. 34 has been put into practical use. In the 34-mode communication procedure, at the time of starting communication and during communication execution, the receiving side designates the communication speed according to the line status at that time, specifically, S / N (signal to noise power ratio) and bandwidth. It is possible for the transmission side to change the communication speed so that transmission is performed at the communication speed specified on the reception side. V. In the case of performing data communication in the 34-mode communication procedure, the same recommendation V. The actual communication speed is determined by performing the pre-procedure in 8 communication procedures.

  2 and 3 are flowcharts showing a facsimile reception process executed by the main control unit 1 of the facsimile machine 20 of FIG.

  In step S1 of FIG. 2, it is determined whether or not an incoming call has been received. If YES, the process proceeds to step S2. If NO, the process returns to step S1 to repeat the process. In step S2, a CNG signal (calling tone) is received and a CED signal (called station confirmation signal) is sent out. In step S3, an NSF signal (non-standard device signal) and a DIS signal (digital identification signal) are transmitted, and a TSI signal (transmission station identification signal) and a DCS signal (digital command signal) are received. In step S4, a training process is performed. In step S5, a CFR signal (reception preparation confirmation signal) is transmitted. In step S6, reception of image data is started from the counterpart facsimile machine. In step S6A, the FSK flag is initialized to zero. At this time, the mode is switched from the low-speed modem mode to the high-speed modem mode. In step S7, it is determined whether image data has been received. If YES, the process proceeds to step S8 in FIG. 3, whereas if NO, the process proceeds to step S15.

  In step S8 of FIG. 3, the received image data is decoded. In step S9, it is determined whether or not an RTC signal that is a predetermined code indicating the end of the image data is detected in the received image data. If YES, the process proceeds to step S19 in FIG. Advances to step S10. In step S10, it is determined whether or not the carrier is disconnected. If YES, the process proceeds to step S11. If NO, the process proceeds to step S12. Specifically, for example, when the carrier signal is cut for a certain time (for example, 6 seconds), it is determined that the carrier is cut. In step S11, a decoding error is determined. In step S12, it is determined whether an error line has been detected in the decoding process in step S8, or whether a decoding error has been determined in step S11 due to a carrier interruption. If YES, the process proceeds to step S13. If NO, Advances to step S14. In step S13, after setting the FSK flag to 1, the process proceeds to step S15 in FIG. In step S14, the FSK flag is set to 0, and then the process proceeds to step S15 in FIG.

  In step S15 of FIG. 2, it is determined whether or not the reception of the image data has been completed. If YES, the process proceeds to step S19. If NO, the process proceeds to step S16. In step S16, it is determined whether or not the FSK flag is 1. If YES, the process proceeds to step S17. If NO, the process returns to step S6A and the process is repeated. In step S17, the frequency component of the FSK signal is detected. The frequency component of the FSK signal is, for example, a frequency component of 1650 Hz. At this time, the high-speed modem mode is switched to the low-speed modem mode. In step S18, it is determined whether or not the frequency component of the FSK signal has been detected. If YES, the process proceeds to step S19. If NO, the process returns to step S6A and the process is repeated. Specifically, when the frequency component of 1650 Hz is continuously detected for 800 msec, it is determined that the frequency component of the FSK signal has been detected. In step S19, for example, a post message signal such as an EOP signal (procedure end signal), an EOM signal (message end signal), or an MPS signal (multipage signal) is received. In step S20, a response signal (for example, MCF signal (message confirmation signal)) for the post message signal is transmitted. In step S21, it is determined whether or not there is a next page based on the data in the post message signal. If YES, the process returns to step S6A to repeat the process. If NO, the process proceeds to step S22. In step S22, a DCN signal (line disconnection command signal) is received from the partner facsimile machine at the normal end, and a line is released by transmitting a DCN signal to the partner facsimile apparatus at the end of the error, and then step S1. Return to and repeat the process.

  As described above, the facsimile apparatus 20 according to the present embodiment includes the NCU 11 and the facsimile modem 10 that receive image data from the facsimile apparatus of the other party by facsimile, and the main control unit 1 receives the image data received by facsimile. When an error line is detected or when it is detected that the carrier signal has been interrupted for a predetermined time or more, it is determined whether or not the frequency component of the FSK signal is detected, and the frequency component of the FSK signal is detected. Control to receive data post message. Here, in the facsimile apparatus 20, when the main control unit 1 does not detect an error line in the image data received by facsimile and does not detect that the carrier signal has been interrupted for a predetermined time or longer, the main control unit 1 determines the frequency component of the FSK signal. Control to stop detection. In the facsimile apparatus 20, the main control unit 1 controls to stop detecting the frequency component of the FSK signal when the RTC signal indicating the end of each page of the image data is received. Therefore, when an error line is detected in the image data received by facsimile or when it is detected that the carrier signal has been interrupted for a predetermined time or more, the frequency component of the FSK signal is detected to thereby detect a predetermined frequency in the image data. Since it is possible to reduce erroneous detection of components and reliably continue the facsimile reception procedure, it is possible to improve the reliability during facsimile reception.

  As described above in detail, according to the communication terminal device of the present invention, when an error line is detected in image data received by facsimile or when it is detected that the carrier signal is interrupted for a predetermined time or more, the FSK signal By detecting the frequency component, erroneous detection of a predetermined frequency component in the image data is reduced, and the facsimile reception procedure is reliably continued, so that the reliability at the time of facsimile reception can be improved.

1 is a block diagram illustrating a configuration of a facsimile machine 20 according to an embodiment of the present invention. 3 is a flowchart showing a facsimile reception process executed by a main control unit 1 of the facsimile apparatus 20 of FIG. 3 is a flowchart showing a facsimile reception process executed by a main control unit 1 of the facsimile apparatus 20 of FIG.

Explanation of symbols

1 ... main control unit (CPU),
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: A facsimile machine.

Claims (3)

Receiving means for receiving image data by facsimile from the communication terminal device of the other party;
When an error line is detected in the image data received by the facsimile or when it is detected that the carrier signal has been interrupted for a predetermined time or more, it is determined whether or not a predetermined frequency component of the facsimile procedure signal has been detected. A communication terminal device comprising: control means for controlling to receive a post message of image data when a frequency component is detected.   The control means controls to stop detecting the predetermined frequency component when detecting no error line in the image data received by the facsimile and not detecting that the carrier signal is interrupted for a predetermined time or longer. The communication terminal device according to claim 1. 3. The communication according to claim 1, wherein the control unit performs control so that detection of the predetermined frequency component is stopped when a signal indicating the end of each page of the image data is received. 4. Terminal device.

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