JPH09261435A - Signal quality discrimination circuit and communication terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To confirm the reception quality of the reception side on the transmission side when communication terminal equipment on the transmission side and reception side is provided with no error correcting function such as error correction mode(ECM). SOLUTION: Concerning a system for performing radio communication while regarding a facsimile signal as a voice signal, a portable telephone terminal 1 connected to facsimile equipment 2 is provided with a signal quality discrimination circuit 10. This signal quality discrimination circuit 10 discriminates signal quality in a radio communication zone by monitoring the level of an interference signal existent at a non-used outgoing channel Ch2 during the transmission of the facsimile signal. Thus, the signal state in the radio zone of an incoming channel Ch1, namely, the quality of the facsimile signal received by facsimile equipment 5 on the reception side can be confirmed (estimated).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal quality judgment circuit and a communication terminal device in a wireless communication system, and more particularly, to a signal quality judgment circuit and a communication terminal device in a system which regards a facsimile signal as a voice signal for wireless communication. It is about.

[0002]

2. Description of the Related Art In recent years, automobile / mobile phone systems and simple mobile phone systems (PHS: Personal Handy-phone S)
wireless fax using a mobile communication terminal
Communication, so-called deemed voice communication is performed. In this deemed voice communication, as shown in FIG. 3, for example, the transmitting side facsimile device 50 and the mobile phone terminal 51 are connected, and the FAX signal output from the facsimile device 50 is transmitted by the mobile phone terminal 51 as a voice signal. Base station 5
2 and the destination network facsimile machine 54 via the network 53
Send to In this way, facsimile transmission similar to the case of using an ordinary analog telephone line can be performed.

In the above-mentioned deemed voice communication and facsimile communication using a normal telephone line, in order to correct an error of the FAX signal received by the receiving side, the transmitting side and the receiving side facsimile apparatuses usually have an error correction mode (EC).
It has an error correction function such as M: Error Correction Mode. In such a facsimile machine, even if an error occurs due to noise in the deemed voice signal transmitted from the mobile phone terminal 51 to the wireless section in the deemed voice communication, an error is generated.
The CM allows the receiving side to receive a relatively high quality signal.

[0004]

However, some facsimile machines do not have the above-mentioned error correction function for the reason of cost reduction and the like. In such a facsimile apparatus, the only guarantee of error is communication protocol control in which the reception side confirms the reception quality in phase D, and when the reception quality is low, a retransmission request is sent to the transmission side. Therefore, the sending side facsimile device cannot confirm how much error has occurred only by sending a retransmission request from the receiving side facsimile device for the transmitted deemed voice signal (FAX signal). That is, the transmitting side device cannot determine how well the receiving side device could receive the FAX signal. Especially, in the assumed voice communication, an error is likely to occur in a situation where a FAX signal is transmitted through a wireless line, a situation where the mobile phone terminal 51 is far away from the base station 52, and the like. Therefore, in the deemed voice communication performed without the error correction function, the user can
There is anxiety about the reception quality of the AX signal.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a transmitting side when a communication terminal device on the transmitting side and a receiving side does not have an error correction function such as ECM. It is an object of the present invention to provide a signal quality determination circuit and a communication terminal device capable of confirming the reception quality on the receiving side.

[0006]

In order to solve the above-mentioned problems, the invention according to claim 1 is a signal quality judgment circuit equipped in a communication terminal device in a system for performing communication by regarding a facsimile signal as a voice signal. The gist of the present invention is to monitor the level of an interfering signal existing in a communication section during the transmission of the facsimile signal to determine the signal quality of the communication section.

According to a second aspect of the present invention, in a system for performing wireless communication in which a facsimile signal is regarded as a voice signal, a signal quality determination circuit equipped in a communication terminal device, wherein during the transmission of the facsimile signal, The gist of the present invention is to monitor the level of an interfering signal existing in a communication channel of the communication terminal device that is not used and determine the signal quality of a wireless communication section.

According to a third aspect of the present invention, the communication terminal device includes a facsimile device and a mobile phone terminal connected to the facsimile device, and the signal quality determination circuit includes:
The gist is that it is installed in the mobile phone terminal.

According to a fourth aspect of the present invention, the communication terminal device includes a facsimile device and a mobile phone terminal connected to the facsimile device, and the signal quality determination circuit includes:
The gist is that it is installed in the fax machine.

According to a fifth aspect of the present invention, a communication terminal device used in a system for performing wireless communication by regarding a facsimile signal as a voice signal is a communication terminal device which is not in use during transmission of the facsimile signal. A signal quality determination unit that determines the signal quality of a wireless communication section by monitoring the level of an interfering signal existing in a communication channel, and outputs information about the reception quality of the facsimile signal based on the determination result of the signal quality determination unit And the output means for

According to a sixth aspect of the invention, the output means is skeptical about the reception quality of the facsimile signal based on the result of the determination by the signal quality determination means that the signal quality of the wireless communication section is low. The point is to output.

According to a seventh aspect of the present invention, the signal quality determining means determines, when the facsimile signal is continuously transmitted in a predetermined unit, a disturbance signal existing in the communication channel for each of the predetermined units. The level is monitored to determine the signal quality in the wireless communication section, and the output means outputs the facsimile signal based on the determination result of the signal quality determination means after the continuous transmission of the facsimile signal is completed. The gist is to output the information about the reception quality in association with the predetermined unit.

According to an eighth aspect of the present invention, the signal quality determining means determines, when the facsimile signal is continuously transmitted in a predetermined unit, a disturbance signal existing in the communication channel for each predetermined unit. The level is monitored to determine the signal quality of the wireless communication section, and the output means, based on the determination result of the signal quality determination means, every time the facsimile signal is transmitted in the predetermined unit. The main point is to output information about the reception quality of the facsimile signal.

(Operation) According to the invention described in claim 1,
During transmission of the facsimile signal, the level of the interfering signal existing in the communication section is monitored to determine the signal quality of the communication section. Therefore, it becomes possible to confirm the reception quality on the receiving side by the communication terminal device on the transmitting side.

According to the second aspect of the present invention, during transmission of the facsimile signal, the level of the interfering signal existing in the unused communication channel is monitored to determine the signal quality of the wireless communication section. Therefore, it becomes possible to confirm the reception quality on the receiving side by the communication terminal device on the transmitting side.

According to the third aspect of the invention, there is provided a portable telephone terminal equipped with a signal quality judging circuit. Claim 4
According to the invention described in (1), there is provided a facsimile apparatus including a signal quality determination circuit.

According to the invention described in claim 5, the signal quality of the wireless communication section is judged by the signal quality judging means during the transmission of the facsimile signal, and based on the judgment result,
Information about the reception quality of the facsimile signal is output by the output means. Therefore, the user can grasp the reception quality based on the information, and the anxiety about the reception quality is eliminated.

According to the sixth aspect of the invention, the output means outputs skeptical information regarding the reception quality of the facsimile signal based on the determination result that the signal quality in the wireless communication section is low. Therefore, the user can grasp the reception quality based on the information and perform processing such as retransmission.

According to the invention described in claim 7, after the continuous transmission of the facsimile signal is completed, the information about the reception quality of the facsimile signal is associated with a predetermined unit based on the determination result of the signal quality determination means. And output.

According to the eighth aspect of the present invention, every time the facsimile signal is transmitted in a predetermined unit, the information about the reception quality of the facsimile signal is output based on the determination result of the signal quality determining means. .

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, in the deemed voice communication according to the present embodiment, the transmission side facsimile apparatus 1 and the analog mobile phone terminal 2 are connected, and the FAX signal output from the facsimile apparatus 1 is transmitted to the mobile phone terminal 2 Is regarded as a voice signal and is transmitted to the receiving side facsimile device 5 via the base station 3 and the line network 4. Between the sending side facsimile apparatus 1 and the receiving side facsimile apparatus 5, a FA is used according to a predetermined communication protocol.
X signals are transmitted and received. In the present embodiment, the manuscript 1
FA generated based on the read image information for pages
The X signal is transmitted as one unit.

The mobile phone terminal 2 includes a FAX connector 6, a voice signal processing circuit 7, a radio circuit 8, a control circuit 9, a signal quality judging circuit 10, for connecting the transmitting side facsimile apparatus 1.
Microphone 11, receiver 12, first and second switches 1
3, 14, an input unit 15 including number keys and function keys, and a display unit 16 such as a liquid crystal display device.

The first switch 13 is a FAX connector 6
The connection between the voice signal processing circuit 7 and the transmission side terminal 6a of the FAX connector 6 and the connection between the processing circuit 7 and the microphone 11 are selectively switched according to the connection / disconnection of the facsimile apparatus 1 to / from. The second switch 14 is also connected to the processing circuit 7 in response to connection / disconnection with the FAX connector 6.
And the connection of the reception side terminal 6b of the FAX connector 6 and the connection of the processing circuit 7 and the receiver 12 are selectively switched.

The audio signal processing circuit 7 is
A microphone amplifier 7 a is provided for amplifying the level of the voice signal output from the microphone 11 or the level of the FAX signal output from the fax machine 1 via the FAX connector 6.
Further, the audio signal processing circuit 7 includes a receiver amplifier 7b that attenuates the level of the FAX signal as the audio signal or the deemed audio signal output from the wireless circuit 8 described later at the time of reception. The audio signal processing circuit 7 also includes a tone generator 7c that generates various tones such as a telephone number input by the input unit 15.

The radio circuit 8 converts a transmission signal into an RF signal at the time of transmission, and an IF signal at the time of reception.
An RF unit 8a for converting to an (intermediate frequency) signal is provided.
Further, the wireless circuit 8 transmits the audio signal and the F
The modulation / demodulation unit 8b is provided which modulates the AX signal and outputs the transmission signal to the RF unit, and when receiving, demodulates the IF signal from the RF unit and outputs the audio signal or the FAX signal to the audio signal processing circuit 7. . In the present embodiment, two frequency bands are assigned to the mobile phone terminal 2, an upstream channel Ch1 for transmission (terminal → base station) and a downstream channel Ch2 for reception (base station → terminal).

The signal quality judgment circuit 10 is connected between the reception side terminal 6b of the FAX connector 6 and the control circuit 9, and confirms the transmission phase (phases A to E) in the facsimile communication protocol. Further, the signal quality determination circuit 10 receives the reception wave signal of the downlink channel Ch2 for reception which is not used during the transmission of the FAX signal in the transmission phase C by the radio circuit 8, the audio signal processing circuit 7 and the second signal.
The signal is input as a determination signal via the switch 14 of. The determination signal includes a low-belel fax signal having a substantially uniform amplitude level, which is reflected from the receiving facsimile machine 5 and transmitted through the line network 4 and the base station 3. If there are noises, communication signals, and various kinds of interference signals such as fading in the wireless section of the downlink channel Ch1, the determination signal also includes the interference signals.

The signal quality judgment circuit 10 monitors the level of the judgment signal in order to judge the signal state in the wireless section. That is, as shown in FIG. 2, the determination circuit 10 determines whether or not the occurrence frequency of various interfering signals having a level L2 exceeding the substantially uniform amplitude level L1 of the reflected FAX signal exceeds a preset reference occurrence frequency. I will check. It should be noted that the reflected fax signal may be ignored, and the level magnitudes of various interfering signals and the frequency of occurrence of the signals may be checked.

When the level occurrence frequency exceeds the reference occurrence frequency, the signal quality judging circuit 10 judges that the wireless space of the receiving downlink channel Ch2 has a lot of noise and the signal condition in the wireless section is bad. Then, the determination result is output to the control circuit 9. That is, by this determination, the signal condition in the wireless space of the uplink channel Ch1 for transmission is also bad,
It is estimated that the quality of the FAX signal received by the receiving facsimile machine is low. The reference generation frequency is preset to a value that allows the user to sufficiently read the received facsimile image information output by the receiving-side facsimile device 5 in the deemed voice communication.

The control circuit 9 stores the determination result of the signal quality determination circuit 10 and confirms via the determination circuit 10 whether or not the facsimile line is disconnected in phase E. When the control circuit 9 confirms that the facsimile line has been disconnected, the reception-side facsimile apparatus 5 is displayed on the screen of the display unit 16 to prompt the user to retransmit based on the determination result of the signal quality determination circuit 10. Display a warning message that the signal may not have been successfully received. Further, when the FAX signal is continuously transmitted, the control circuit 9 stores the determination result of the signal quality determination circuit 10 in association with the number of pages of the transmission document. Then, based on the determination result, a warning message is displayed on the screen of the display unit 16 indicating that the FAX signal of the page of the original may not have been normally received.

Now, with the transmitting side facsimile apparatus 1 connected to the portable telephone terminal 2 configured as described above,
The user operates the fax machine 1 to enter the telephone number (FAX
Number) and press the start key 1a.
As shown in FIG. 2, in phase A, the facsimile machine 5 on the receiving side is connected to the facsimile line, and the called terminal identification signal is returned from the receiving side. Next, in phase B, preparation for transmission of a FAX signal is performed between the transmission side and the reception side, and in phase C, the FAX signal is modulated by the mobile phone terminal 2 into a transmission signal as a deemed voice signal. The transmission signal is converted into an RF signal and transmitted from the antenna 17 to the band of the upstream channel Ch1.

When the signal quality judgment circuit 10 confirms that the phase is C, the received wave signal of the unused downlink channel Ch2 for reception is transmitted to the radio circuit 8, the audio signal processing circuit 7 and the second switch 14. It is input as a determination signal through the monitor and the level of the determination signal is monitored. When the signal quality judging circuit 10 judges that the signal condition of the receiving downlink channel Ch2 in the wireless space is bad based on the judging signal, it outputs the judgment result to the control circuit 9. If the signal condition is good, nothing is output.

Next, in phase D, the transmission / reception of FAX signals for one page of the original document and the presence / absence of continuous transmission are confirmed. When continuous transmission is performed, the control signal returns to phase C again. , FAX signals are transmitted. Also at this time, the signal quality determination circuit 10 determines the signal state of the wireless section of the downlink channel Ch2. In this way, when the facsimile line is disconnected in phase E through phase D, the control circuit 9 cannot correctly receive the FAX signal on the screen of the display unit 16 by the receiving facsimile device 5 based on the determination result. Warning message that there is a possibility. Further, when the FAX signal is continuously transmitted, the control circuit 9 normally receives the FAX signal of the page of the document on the screen of the display unit 16 based on the determination result and the number of pages of the related transmission document. Display a warning message that it may not have occurred.

As described above, according to this embodiment, the following effects can be obtained. (1) During the transmission of the FAX signal, the signal state of the wireless section of the downlink channel Ch2 which is not used is determined on the transmission side (the mobile phone terminal 2). Therefore, based on the determination result, it is possible to estimate the signal state in the wireless section of the upstream channel Ch1 for transmission, that is, the quality of the FAX signal received by the receiving side facsimile apparatus.

(2) Based on the determination result of the signal state in the wireless section of the downlink channel Ch2, when the signal state is bad due to a lot of noise, the receiving side displays FAX on the screen of the display unit 16.
Added a warning message to the effect that the signal may not have been received normally. Therefore, the user on the transmission side can grasp the reception quality of the reception side by the warning display, and can perform the deemed voice communication without making the user feel uneasy about the reception quality.

(3) When continuous transmission of FAX signals is performed, a message indicating that the FAX signal of the original of which page may not have been normally received is displayed as a warning. Therefore, the user, based on the warning display,
Retransmission can be performed and confirmation can be made to the receiving side only for the original document related to the transmission failure, which improves the efficiency of the user's transmission work.

The present invention is not limited to the above embodiment, but may be carried out as follows. (A) In the above-described embodiment, the message about the reception quality is displayed on the screen of the display unit 16, but instead, the message may be warned from the receiver 12 by voice.

(B) In the above embodiment, the assumed voice communication is performed by using the facsimile device on the transmitting side and the receiving side. However, it is considered that the transmitting side and / or the receiving side is using the FAX modem and the personal computer. It may be voice communication.

(C) In the above embodiment, the signal quality judgment circuit 10 is provided in the mobile phone terminal 2, but it may be provided in the transmission side facsimile device 1. (D) In the above embodiment, the message is displayed on the screen of the display unit 16 after the transmission of all the fax signals is completed. However, every time the transmission of the fax signal in page units is completed, When it is estimated that the reception quality on the receiving side is low, a message about the reception quality may be displayed on the screen of the display unit 16.

(E) In the above embodiment, the message is displayed on the screen of the display unit 16 as a warning only when the signal condition of the downlink channel Ch2 is bad. However, when the signal condition is good, the receiving side is A message indicating that the FAX signal has been normally received may be displayed.

(V) The present invention may be applied not only to analog mobile phone terminals but also to deemed voice communication using digital mobile phone terminals of the PDC (Personal Digital Cellular) system or the like.

[0041]

As described in detail above, according to the present invention, when the communication terminal devices on the transmitting side and the receiving side do not have an error correction function such as ECM, the transmitting side confirms the receiving quality on the receiving side. can do.

[Brief description of drawings]

FIG. 1 is a block diagram showing a mobile phone terminal including a signal quality determination circuit.

FIG. 2 is an explanatory diagram of signal quality determination.

FIG. 3 is an explanatory diagram for explaining deemed voice communication.

[Explanation of Codes] 1 ... Facsimile device, 2 ... Mobile phone terminal (1 and 2 are included in communication terminal device), 10 ... Signal quality judging circuit as signal quality judging means, 9 ... Control circuit, 16 ... Display Section (9 and 16 constitute an output means), Ch1 ... upstream channel for transmission, Ch2 ... downstream channel for reception.

Claims (8)

[Claims] 1. A communication terminal device (1, 2) in a system in which a facsimile signal is regarded as a voice signal for communication.
A signal quality determination circuit (10) equipped in the device, wherein the level of an interfering signal existing in a communication section is monitored during transmission of the facsimile signal to determine the signal quality of the communication section. Signal quality judgment circuit. 2. In a system for performing wireless communication by regarding a facsimile signal as a voice signal, a communication terminal device (1,
A signal quality judgment circuit (10) equipped in 2), wherein a communication channel (Ch2) of the communication terminal device (1, 2) which is not used during transmission of the facsimile signal.
A signal quality judging circuit characterized by judging the signal quality of a wireless communication section by monitoring the level of an interfering signal existing in. 3. The communication terminal device (1, 2) includes a facsimile device (1) and a mobile phone terminal (2) connected to the facsimile device (1), and the signal quality determination circuit (10). The signal quality judgment circuit according to claim 1 or 2, characterized in that the signal quality judgment circuit is installed in the mobile phone terminal (2). 4. The communication terminal device (1, 2) includes a facsimile device (1) and a mobile phone terminal (2) connected to the facsimile device (1), and the signal quality determination circuit (10). The signal quality judgment circuit according to claim 1 or 2, characterized in that the signal quality judgment circuit is installed in the facsimile device (1). 5. A communication terminal device (1, 2) used in a system for performing wireless communication by regarding a facsimile signal as a voice signal, wherein the communication terminal device (1, 2) which is not used during transmission of the facsimile signal. 2) Communication channel (Ch2)
Based on the determination result of the signal quality determining means (10) for determining the signal quality of the wireless communication section by monitoring the level of the interfering signal existing in
A communication terminal device, comprising: an output unit (9, 16) for outputting information on the reception quality of the facsimile signal. 6. The output means (9, 16) is skeptical about the reception quality of the facsimile signal based on the result of the determination by the signal quality determination means (10) that the signal quality of the wireless communication section is low. The communication terminal device according to claim 5, wherein the communication terminal device outputs information. 7. The signal quality judgment means (10), when the facsimile signal is continuously transmitted in a predetermined unit, the communication channel (Ch2) in every predetermined unit.
The level of an interfering signal present in the wireless communication section to determine the signal quality of the wireless communication section, and the output means (9, 16) determines the signal quality determination means after the continuous transmission of the facsimile signal is completed. (1
The communication terminal device according to claim 5, wherein the communication terminal device outputs the information about the reception quality of the facsimile signal in association with the predetermined unit based on the determination result of 0). 8. The signal quality judgment means (10), when the facsimile signal is continuously transmitted in a predetermined unit, the communication channel (Ch2) in every predetermined unit.
The level of a disturbing signal present in the wireless communication section to determine the signal quality in a wireless communication section, and the output means (9, 16) outputs the signal every time the facsimile signal is transmitted in the predetermined unit. 6. The communication terminal device according to claim 5, wherein the communication terminal device outputs information on the reception quality of the facsimile signal based on the determination result of the quality determination means (10).