JP2010246139A - Voice communication apparatus and voice communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an advantage of voice quality even if an already existing telephone etc. utilizes a broad-band transmission path, such as an IP network. <P>SOLUTION: A voice communication apparatus is interposed between a telephone and a broad-band transmission path having a communication band broader than the voice band limited by the call-transmission characteristics and the call-reception characteristics of the telephone and has a transmission system frequency characteristic correction means for correcting the frequency characteristics of a call-transmission signal from the telephone, a reception system frequency characteristic correcting means for correcting the frequency characteristics of a call-reception signal to the telephone, and a corrected frequency characteristic setting means for measuring the call-transmission characteristics or the call-reception characteristics of the telephone and variably setting the corrected frequency characteristics of the transmission system frequency characteristic correcting means and the reception system frequency characteristic correcting means in accordance with the measurement result. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a voice communication apparatus and a voice communication system, for example, a voice communication apparatus incorporated in a telephone, a voice communication apparatus containing a telephone, and a voice communication system having the voice communication apparatus as an element.

  In recent years, voice communication (VoIP) using an IP network such as the Internet has become popular. Also in voice communication using such an IP network, a voice signal band limited to 4 kHz (so-called telephone band signal) has been transmitted.

  This is due to the restriction that an audio signal of 4 kHz or higher should not be input in a wired transmission line (general public telephone network). However, there is no such limitation in the IP network, and voice communication using a wide band (a signal having a band of 4 kHz or more) is possible.

  However, in an existing normal telephone that is not an IP network telephone (IP dedicated telephone), a wideband signal captured by a transmitter (microphone) is band-limited to 4 kHz or less as shown in FIG. 2. A speech reception characteristic (for example, a band filter) having a speech characteristic (for example, a band filter) and generating a sound from a receiver (speaker) by limiting the band of a received signal from the transmission path to 4 kHz or less as shown in FIG. (By filter). For this reason, even if the transmission path permits a band signal of 4 kHz or higher as in the IP network, only voice communication quality equivalent to that in the case of a general public telephone network can be achieved.

  Therefore, in order to realize high-quality communication using a broadband signal using an IP network, the telephone itself needs to have broadband transmission characteristics and reception characteristics.

  However, many existing telephones in the world have transmission characteristics and reception characteristics that limit the bandwidth to 4 kHz or less as described above, and transmission like an IP network that allows broadband signals. It is not possible to enjoy the merit of voice quality through the road.

  Therefore, there is a demand for a voice communication device and a voice communication system that can obtain voice quality merit even when an existing telephone or the like uses a transmission path such as an IP network that allows wideband signals. .

  The voice communication apparatus according to the first aspect of the present invention is: (1) a voice communication apparatus interposed between a telephone and a broadband transmission line having a wider communication band than the voice band limited by the transmission characteristics and reception characteristics of the telephone. And (2) transmission system frequency characteristic correction means for correcting the frequency characteristic of the transmission signal from the telephone, and (3) reception system frequency characteristic correction means for correcting the frequency characteristic of the reception signal to the telephone. (4) Correction frequency characteristics for measuring transmission characteristics and / or reception characteristics of the telephone and variably setting the correction frequency characteristics of the transmission frequency characteristic correction means and the reception frequency characteristic correction means according to the measurement result And setting means.

  According to a second aspect of the present invention, there is provided a voice communication system in which two telephones as call partners are connected via a broadband transmission line having a wider communication band than a voice band in which a transmission characteristic and a reception characteristic of each telephone are limited. The telephones are connected to the broadband transmission line via the voice communication apparatus according to the first aspect of the present invention.

  According to the present invention, it is possible to realize a voice communication apparatus and a voice communication system capable of obtaining voice quality merit even when an existing telephone or the like uses a broadband transmission path.

It is a block diagram which shows the structure of the audio | voice communication system of 1st Embodiment. It is explanatory drawing which shows the transmission characteristic and reception characteristic of a general telephone. It is a block diagram which shows the principal part structure of the audio | voice communication apparatus of 1st Embodiment. It is explanatory drawing of the function of the transmission F special correction | amendment part of 1st Embodiment. It is explanatory drawing of the function of the reception F special correction | amendment part of 1st Embodiment. It is explanatory drawing which shows the frequency characteristic example of the input audio | voice signal with which operation | movement description of 1st Embodiment is provided. It is a block diagram which shows the structure of the transmission F special correction | amendment part of 2nd Embodiment. It is explanatory drawing which shows the correction frequency characteristic of each correction filter of FIG. It is a block diagram which shows the principal part structure of the audio | voice communication apparatus of 3rd Embodiment. It is a block diagram which shows the principal part structure of the audio | voice communication apparatus of 4th Embodiment. It is a block diagram which shows the principal part structure of the audio | voice communication apparatus of 5th Embodiment.

(A) First Embodiment Hereinafter, a first embodiment of a voice communication apparatus and a voice communication system according to the present invention will be described with reference to the drawings.

(A-1) Configuration of the First Embodiment FIG. 1 is a block diagram showing the configuration of the voice communication system 1 of the first embodiment.

  In FIG. 1, a voice communication system 1 according to a first embodiment executes communication between two end nodes via an IP network 2.

  Each end node includes the voice communication devices 10 and 20 of the first embodiment and telephones 11 and 12 accommodated in the voice communication devices 10 and 20. Note that the telephones 11 and 12 may be facsimile apparatuses or the like as long as they transmit signals in a voice band that is band-limited by a general public telephone network.

  In the case of the first embodiment, each of the telephones 11 and 12 is an existing telephone having transmission characteristics and reception characteristics that limit the band to 4 kHz or less. Therefore, the illustration of the internal configuration is omitted, and the functional description of each part is omitted.

  Each of the voice communication devices 10 and 20 processes a voice signal so as to be compatible with broadband communication by the IP network 2, and includes a characteristic configuration of the transmission system shown in FIG. 3A and a configuration shown in FIG. It has the characteristic configuration of the receiving system.

  The characteristic configuration of the transmission system in each of the voice communication apparatuses 10 and 20 includes a transmission F special correction unit 31 and a voice-IP packet conversion unit 32.

  The transmission F special correction unit 31 is composed of, for example, an analog filter or a digital filter, and includes a voice signal (including a signal other than voice such as a facsimile signal) output from the corresponding telephones 11 and 12 toward the IP network 2. The frequency characteristic (F characteristic) is flattened over the entire predetermined voice band. For example, the frequency characteristics of an audio signal output from the telephones 11 and 12 and band-limited in consideration of a general public telephone network as shown in FIG. The limit is increased and the limit is restored as shown in FIG. FIG. 4C shows the correction frequency characteristic by the transmission F special correction unit 31. FIG. 4 shows an example in which 0 to 8000 Hz is flattened as the audio band, but the present invention is not limited to this. Moreover, it is not limited to a perfect flat, You may have some distortion.

  Here, since the models of the telephones 11 and 12 connected to the voice communication apparatuses 10 and 20 are not fixed, the transmission F special correction unit 31 that can change the correction frequency characteristic is applied, and the voice communication apparatuses 10 and 20 are applied. It is preferable that the installation operator or the like can adjust the correction frequency characteristic by operating the operation element or the like (see the second embodiment).

  The voice-IP packet conversion unit 32 assembles an IP packet that can be sent to the IP network 2 from the voice signal after the frequency characteristic correction output from the transmission F special correction unit 31.

  The characteristic configuration of the reception system in each of the voice communication apparatuses 10 and 20 includes an IP packet-voice conversion unit 41 and a reception F special correction unit 42.

  The IP packet-speech conversion unit 41 decomposes the IP packet that has arrived from the IP network 2 side and restores the voice signal. The restored frequency characteristic of the audio signal has been subjected to correction processing by the transmission F special correction unit 31 and is similar to the frequency characteristic of the audio signal output from the transmission F special correction unit 31.

  The reception F special correction unit 42 is constituted by, for example, an analog filter, and performs correction for raising the band component attenuated by the reception characteristic in advance in consideration of the reception characteristic of the corresponding telephones 11 and 12. For example, when the reception characteristics of the telephones 11 and 12 are as shown in FIG. 5A in consideration of a general public telephone network, the frequency characteristics of the voice signal from the IP packet-voice conversion unit 41 (the above-described figure). 4 (B)) is preliminarily raised for the band component attenuated by the reception characteristic and corrected to an audio signal having a frequency characteristic as shown in FIG. 5 (B). FIG. 5C shows a correction frequency characteristic by the reception F special correction unit 42. Although FIG. 5 shows an example in which the frequency range of 0 to 8000 Hz is corrected, the correction frequency range is not limited to this.

  Here, since the models of the telephones 11 and 12 connected to the voice communication apparatuses 10 and 20 are not fixed, the reception F special correction unit 42 that can change the correction frequency characteristic is applied, and the voice communication apparatuses 10 and 20 are applied. It is preferable that the installation operator or the like can adjust the correction frequency characteristic by operating the operation element or the like (see the second embodiment).

(A-2) Operation of the First Embodiment Next, the operation of the voice communication system 1 of the first embodiment will be described. In the following description, it is assumed that the telephone 11 is a voice signal transmitting telephone and the telephone 12 is a voice signal receiving telephone.

  The voice produced by the user of the telephone 11 is captured by the transmitter 11S of the telephone 11 and converted into an electric signal (voice signal). The voice signal is taken into account by the telephone main body 11B in consideration of a general public telephone network. Bandwidth is limited. In the following description, it is assumed that the frequency characteristic of the audio signal from the transmitter 11S is flat throughout the entire audio band as shown in FIG. Here, being flat throughout the entire voice band means that the frequency characteristic is flat at, for example, 8 kHz or less.

  In this case, the audio signal after being band-limited by the telephone main body 11B has a low frequency (300 Hz or less) or a high frequency (3400 Hz or more) attenuated as shown in FIG.

  The transmission F special correction unit 31 of the voice communication apparatus 10 to which such a band-limited voice signal is given has the frequency of the input voice signal based on the correction frequency characteristic (see FIG. 4C) that the transmission F special correction unit 31 has. The characteristic is corrected, and an audio signal having a frequency characteristic that is flat over the entire audio band is output as shown in FIG.

  The voice signal after the frequency characteristic correction output from the transmission F special correction unit 31 is converted into an IP packet by the voice-IP packet conversion unit 32 and transmitted to the IP network 2.

  The IP packet-voice conversion unit 41 of the voice communication apparatus 20 to which the IP packet is input from the IP network 2 side restores the voice signal by decomposing the IP packet, and the restored voice signal is sent to the reception F special correction unit 42. Given.

  The restored audio signal has a frequency characteristic similar to that shown in FIG. 4B, but is attenuated by the reception characteristic by the reception F special correction unit 42 having the correction frequency characteristic shown in FIG. 5C. The band component is lifted in advance and converted into an audio signal having frequency characteristics as shown in FIG.

  The telephone body 12B attenuates the low frequency and high frequency in the input audio signal by its reception characteristics, but since the attenuation band is raised in advance by the reception F special correction unit 42, the attenuated audio signal is This is the same as the frequency characteristic (see FIG. 6) of the voice signal captured by the transmitting telephone set 11, and the voice signal is sounded and output from the receiver 12R.

(A-3) Effects of First Embodiment As described above, according to the first embodiment, voice communication is performed via a broadband transmission path (IP network) by a telephone set compatible with the general public network. In addition, the frequency communication correction function of the voice communication apparatus can perform communication using a wideband voice signal, and the voice quality can be improved.

(B) Second Embodiment Next, a second embodiment of the voice communication apparatus and the voice communication system according to the present invention will be briefly described with reference to the drawings.

  The insertion position on the system of the voice communication apparatus of the second embodiment is the same as that of FIG. 1 according to the first embodiment.

  In the case of the second embodiment, the transmission F special correction unit 31 and the reception F special correction unit 42 in the voice communication apparatuses 10 and 20 are different from those of the first embodiment.

  FIG. 7 is a block diagram showing a detailed configuration of the transmission F special correction unit 31 in the second embodiment. The detailed configuration of the reception F special correction unit 42 is the same as the detailed configuration of the transmission F special correction unit 31.

  The transmission F special correction unit 31 of the second embodiment includes a plurality (three in FIG. 7) of correction filters 31-1, 31-2, and 31-3, and the plurality of correction filters 31-1. , 31-2 and 31-3, a selection switch 31S for selecting one of them.

  The correction filters 31-1, 31-2, and 31-3 have different correction frequency characteristics according to the transmission characteristics of the telephones 11 and 12, as shown in FIGS.

  The selection switch 31S enables one correction filter 31-1, 31-2, or 31-3 according to a selection signal from the outside. The selection switch 31S may be provided on the input side of the correction filters 31-1, 31-2, and 31-3, may be provided on the output side, and may further be provided on the input side and the output side. It may be provided on both sides.

  The selection signal to the selection switch 31S may be based on an operation of a user or an installation worker of the voice communication apparatuses 10 and 20, or may be automatically generated by the apparatus (third To the fifth embodiment), or may be acquired from an external device. In the case of importing from an external device, for example, information on the correspondence relationship between the telephone type and the corrected frequency characteristic is stored in a server on the IP network 2, and the telephone type is input using the PB button of the telephone. And obtaining a selection signal from the server.

  For example, when connecting the voice communication devices 10 and 20 to the telephones 11 and 12, the user, the installation worker of the voice communication devices 10 and 20, etc. conducts a telephone call experiment or the like with each correction filter selected, and the optimum The correction filter is determined, and the voice communication apparatuses 10 and 20 are set with the determined optimal correction filter.

  The subsequent operation during a call is the same as that in the above-described first embodiment, and a description thereof will be omitted.

  As described above, according to the second embodiment, the same effect as that of the first embodiment can be obtained, and in addition to this, the correction frequency characteristic can be changed according to the type of the telephone connected to the voice communication device. Since it can be selected, there is an effect that the call quality can be further improved.

(C) Third Embodiment Next, a third embodiment of the voice communication apparatus and the voice communication system according to the present invention will be described with reference to the drawings.

  The insertion position on the system of the voice communication apparatus of the third embodiment is the same as that of FIG. 1 according to the first embodiment.

  In the case of the third embodiment, the internal characteristic configuration of the voice communication apparatus is different from that of the first embodiment, and the characteristic configuration is shown in FIG. In FIG. 9, the same and corresponding parts as those in FIG. 3 according to the first embodiment are denoted by the same reference numerals.

  The voice communication apparatuses 10 and 20 according to the third embodiment include four switches in addition to the transmission F special correction unit 31, the voice-IP packet conversion unit 32, the IP packet-voice conversion unit 41, and the reception F special correction unit 42. 51A to 51D, a frequency analysis unit 52, a white noise generator 53, and an operation mode control unit 54. The transmission F special correction unit 31 and the reception F special correction unit 42 according to the third embodiment can change the correction frequency characteristic.

  In the case of the third embodiment, there are a normal mode and an F special setting mode for setting a correction frequency characteristic as operation modes.

  When the F special setting mode is instructed (or, for example, when the initial connection between the telephones 11 and 12 and the voice communication devices 10 and 20 is automatically detected), the operation mode control unit 54 transmits the F special correction unit. Each unit is operated so that the correction frequency characteristics of 31 and the reception F special correction unit 42 are automatically set.

  The four switches 51A to 51D are for switching signal paths between the normal mode and the F special setting mode.

  The frequency analysis unit 52 includes, for example, an FFT unit and functions in the F special setting mode. The frequency analysis unit 52 is used to detect the frequency characteristic of the signal given from the connected telephone set 11 or 12.

  The white noise generator 53 generates white noise when viewed in the entire voice band, and functions in the F special setting mode.

  Next, the operation of the voice communication apparatuses 10 and 20 in the F special setting mode will be described. In FIG. 9, the telephone is omitted, but the telephone is also described using the reference numerals in FIG.

  When the F special setting mode is instructed, first, the operation mode control unit 54 connects the switches 51A to 51D to the a terminal, and then activates the frequency analysis unit 52.

  At this time, a signal of background noise (which is assumed to be white noise in the third embodiment) captured by the transmitters 11S and 12S of the telephones 11 and 12 connected to the voice communication apparatuses 10 and 20 is used. On the other hand, a signal reflecting the transmission characteristics of the telephone bodies 11B and 12B is input to the frequency analysis unit 52. Thereby, the frequency analysis unit 52 detects the transmission characteristics of the telephones 11 and 12 and causes the transmission F special correction unit 31 to set a correction frequency characteristic corresponding to the transmission characteristics.

  For example, in the case where the transmission F special correction unit 31 has the configuration of the second embodiment, the measured transmission characteristics have a small attenuation in the low range (300 Hz or less) or the high range (3400 Hz or more). If so, the correction filter 31-3 in FIG. 7 is selected. Further, if a digital field whose characteristics can be changed for each frequency is applied as the transmission F special correction unit 31, the transmission F special correction unit 31 so as to realize a reverse characteristic of the measured transmission characteristic. Set the F characteristics of

  Next, the operation mode control unit 54 connects the switches 51A and 51B to the b terminal, the switch 51C to the a terminal, and connects the switch 51D to the c terminal, and then activates the frequency analysis unit 52 and the white noise generator 53. Let

  At this time, the white noise generator 53 generates white noise, and the generated white noise is influenced by the reception characteristics of the telephone bodies 11B and 12B, and then is emitted from the receivers 11R and 12R. The sound output is captured by the transmitters 11S and 12S, and the transmission characteristics of the telephone bodies 11B and 12B are reflected, and then input to the frequency analysis unit 52 via the transmission F special correction unit 31.

  Since the correction frequency characteristic of the transmission F special correction unit 31 is set so as to recover the band limitation of the transmission characteristic, the signal input to the frequency analysis unit 52 at this time is the telephone 11, It can be considered that only 12 reception characteristics are reflected. The frequency analysis unit 52 detects the reception characteristics of the telephones 11 and 12 and causes the reception F special correction unit 42 to set a correction frequency characteristic corresponding to the reception characteristics.

  When the processing as described above is completed, the operation mode control unit 54 connects all the switches 51A to 51D to the b terminal and shifts to the normal mode.

  As described above, according to the third embodiment, the same effect as that of the first embodiment can be obtained, and in addition to this, the transmission characteristics and reception characteristics of the telephone connected to the voice communication device are measured. Thus, the correction frequency characteristic can be set, so that the correction frequency characteristic can be set for each telephone and the call quality can be further improved.

(D) Fourth Embodiment Next, a fourth embodiment of the voice communication apparatus and the voice communication system according to the present invention will be described with reference to the drawings.

  FIG. 10 is a block diagram showing an internal characteristic configuration of the voice communication apparatus according to the fourth embodiment. The same reference numerals are given to the same and corresponding parts as those in FIG. 9 according to the third embodiment. . In the voice communication device of the fourth embodiment, the switch 51D and the white noise generator 53 in the third embodiment are omitted.

  The voice communication devices 10 and 20 of the fourth embodiment are based on the characteristic that the transmission characteristics and the reception characteristics of the telephones 11 and 12 are similar, and the operation in the F special setting mode is the third. This is different from the embodiment.

  When the F special setting mode is instructed, the operation mode control unit 54 first connects the switches 51A to 51C to the a terminal and then activates the frequency analysis unit 52.

  At this time, a signal of background noise (which is assumed to be white noise in the fourth embodiment) captured by the transmitters 11S and 12S of the telephones 11 and 12 connected to the voice communication apparatuses 10 and 20 is used. On the other hand, a signal reflecting the transmission characteristics of the telephone bodies 11B and 12B is input to the frequency analysis unit 52. As a result, the frequency analysis unit 52 detects the transmission characteristics of the telephones 11 and 12, and transmits the corrected frequency characteristics of the transmission system and the reception system according to the transmission characteristics to the transmission F special correction unit 31 and the reception F special correction unit. 42 is set.

  When the above process is completed, the operation mode control unit 54 connects all the switches 51A to 51C to the b terminal and shifts to the normal mode.

  As described above, according to the fourth embodiment, the same effects as those of the third embodiment can be obtained.

(E) Fifth Embodiment Next, a fifth embodiment of the voice communication apparatus and the voice communication system according to the present invention will be described with reference to the drawings.

  FIG. 11 is a block diagram showing an internal characteristic configuration of the voice communication apparatus according to the fifth embodiment. The same reference numerals are given to the same and corresponding parts as those in FIG. 9 according to the third embodiment. .

  The voice communication device according to the fifth embodiment includes voice communication device main bodies 10A and 20A and F-special measurement accessory devices 10B and 20B.

  The F special measurement accessory devices 10B and 20B function only in the F special setting mode, and are connected to the voice communication apparatus main bodies 10A and 20A only in the F special setting mode by an installation operator or the like. It may be always connected to the voice communication apparatus main bodies 10A and 20A, and is accommodated in the voice communication apparatus main bodies 10A and 20A, and is taken out and used only by the installation worker in the F special setting mode. It may be.

  The F special measurement accessory devices 10B and 20B include a white noise generator 53, a speaker 55, a microphone 56, and a switch 57A. On the other hand, the voice communication device main bodies 10A and 20A include a frequency analysis unit 52, an operation mode control unit 54, and switches 57B to 57E as components for F special setting.

  Next, the operation of the voice communication apparatuses 10 and 20 of the fifth embodiment in the F special setting mode will be described.

  Before instructing the F special setting mode, the worker makes the speaker 55 and the microphone 56 of the F special measurement accessory devices 10B and 20B approach the transmitters 11S and 12S and the receivers 11R and 12R, respectively. For example, it is preferable that the external shape of the accessory devices 10B and 20B for F-species measurement be a shape on which the handset 13 can be placed, and that when the handset 13 is placed, it automatically approaches and opposes.

  When the F special setting mode is instructed, first, the operation mode control unit 54 sets the switches 57A to 57E to the a terminal, b terminal, off (a state where neither the a terminal nor the b terminal is connected), a terminal, off. Then, the white noise generator 53 and the frequency analysis unit 52 are activated.

  At this time, the white noise generator 53 generates white noise, which is generated by the speaker 55 and captured by the transmitters 11S and 12S of the telephones 11 and 12 connected to the voice communication apparatuses 10 and 20. Then, a signal reflecting the transmission characteristics of the telephone bodies 11B and 12B is input to the frequency analysis unit 52.

Thereby, the frequency analysis unit 52 detects the transmission characteristics of the telephones 11 and 12 and causes the transmission F special correction unit 31 to set a correction frequency characteristic corresponding to the transmission characteristics.

  Next, the operation mode control unit 54 turns on the switches 57A to 51E for the b terminal, off (a state where neither the a terminal nor the b terminal is connected), the b terminal, the b terminal, and on, and then generates white noise. The unit 53 and the frequency analysis unit 52 are activated.

  At this time, the white noise generator 53 generates white noise, and the generated white noise is influenced by the reception characteristics of the telephone bodies 11B and 12B, and then is emitted from the receivers 11R and 12R. This sound output is captured by the microphone 56 and input to the frequency analysis unit 52.

  At this time, the signal input to the frequency analysis unit 52 reflects only the reception characteristics of the telephones 11 and 12 with respect to white noise. The frequency analysis unit 52 detects the reception characteristics of the telephones 11 and 12 and causes the reception F special correction unit 42 to set a correction frequency characteristic corresponding to the reception characteristics.

  When the processing as described above is completed, the operation mode control unit 54 turns off the switches 57A to 51E (a state in which neither the a terminal nor the b terminal is connected), a terminal, a terminal, or off (also in the a terminal). In a state where the terminal b is not connected to the terminal b), the terminal is turned off to shift to the normal mode.

  As described above, according to the fifth embodiment, the same effect as that of the third embodiment can be obtained, and in addition to this, the transmission characteristic and the reception characteristic are also measured using generated white noise. In addition, since the correction frequency characteristic can be set, it is possible to further improve the call quality.

(F) Other Embodiments In each of the above embodiments, the voice communication apparatus has been described as an apparatus having a frequency characteristic correction function according to the transmission characteristics and reception characteristics of a telephone and a communication function with an IP network. Further, it may be constructed as a device having only a function of correcting frequency characteristics according to transmission characteristics and reception characteristics, or may be constructed as a device having other functions. As an example of the latter case, a gateway device that switches and connects a telephone to either a general public telephone network or an IP network can be cited. In this case, the above-described characteristic configuration functions only when connecting to an IP network. You may do it.

  In each of the above embodiments, the voice communication device is shown separately from the telephone. However, the voice communication apparatus may be incorporated in the telephone. Even in this case, since the basic telephone configuration is the same as that of the conventional telephone set, it is possible to improve the call quality by broadband communication without requiring a design change of that part. The term “voice communication device” in the claims includes this case.

  Further, in each of the above-described embodiments, the transmission F special correction unit has a correction characteristic that makes the corrected frequency characteristic flat across the entire voice band, and the reception F special correction unit determines that the corrected signal is affected by the reception characteristic. The transmission F characteristic correction unit has a correction characteristic such that the corrected frequency characteristic has a predetermined frequency characteristic. The reception F special correction unit may have a correction characteristic such that the frequency characteristic after being affected by the reception characteristic has a predetermined frequency characteristic, and these correction characteristics are completely in correspondence with each other. It doesn't even have to be a thing.

The predetermined frequency characteristic here may be a characteristic that improves the quality of the call through the broadband transmission path as compared with the case where it is merely affected by the transmission characteristic or the reception characteristic.

  DESCRIPTION OF SYMBOLS 1 ... Voice communication system, 2 ... IP network, 10, 20 ... Voice communication apparatus, 10A, 20A ... Voice communication apparatus main body, 10B, 20B ... F special measurement accessory apparatus, 11, 12 ... Telephone, 31 ... Transmission F Special correction unit, 31-1 to 31-3 ... correction filter, 31S, 51A to 51D, 57A to 57E ... switch, 42 ... reception F special correction unit, 52 ... frequency analysis unit (FFT), 53 ... white noise generator 54 ... operation mode control unit, 55 ... speaker, 56 ... microphone.

Claims (5)

A voice communication device interposed between a telephone and a broadband transmission line having a wider communication band than a voice band in which a transmission characteristic and a reception characteristic of the telephone are limited,
Transmission frequency characteristic correcting means for correcting the frequency characteristic of the transmission signal from the telephone;
A receiving system frequency characteristic correcting unit for correcting a frequency characteristic of a received signal to the telephone; and a transmitting characteristic and / or a receiving characteristic of the telephone are measured, and the transmitting system frequency characteristic correcting unit and the receiving system are measured according to a measurement result. And a correction frequency characteristic setting means for variably setting the correction frequency characteristic of the frequency characteristic correction means.   2. The voice communication apparatus according to claim 1, wherein the correction frequency characteristic setting means uses the measurement result of the transmission characteristic of the telephone as the measurement result of the reception characteristic of the telephone. The correction frequency characteristic setting means is
A white noise generating unit that generates white noise;
A transmission characteristic measuring unit that generates a white noise generated by the white noise generation unit and processes a signal obtained by the transmitter capturing the white noise that is generated and output to measure a transmission characteristic;
The white noise generated by the white noise generating unit is output as a sound from the receiver, and has a reception characteristic measuring unit that captures and processes the white noise that is generated and output to measure the reception characteristic,
The voice communication apparatus according to claim 1, wherein correction frequency characteristics of the transmission system frequency characteristic correction unit and the reception system frequency characteristic correction unit are set according to a measurement result. The correction frequency characteristic setting means is
A white noise generating unit that generates white noise, a white noise output unit that generates and outputs the white noise generated by the white noise generating unit, and a signal that captures the sound output by the telephone receiver A speech processing unit that measures a transmission characteristic by processing a signal obtained by capturing a white noise output by a transmitter from the white noise output unit of an external measurement device including a signal return unit that supplies the device to the apparatus. A characteristic measuring unit;
The signal of the device for measurement that has received white noise from the white noise generation unit of the device for measurement and that has output the white noise from the handset of the telephone and captured the white noise that has been produced and output. A reception characteristic measuring unit that processes the signal supplied from the reflux unit and measures the reception characteristic;
The voice communication apparatus according to claim 1, wherein correction frequency characteristics of the transmission system frequency characteristic correction unit and the reception system frequency characteristic correction unit are set according to a measurement result. In a voice communication system in which two telephones of the other party are connected via a broadband transmission line having a wider communication band than the voice band in which the transmission characteristics and reception characteristics of each telephone are limited,
A voice communication system, wherein each of the telephones is connected to the broadband transmission line via the voice communication apparatus according to any one of claims 1 to 4.

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