JPH08223305A - Voice conference system - Google Patents

Abstract

PURPOSE: To realize a voice conference system without troublesoure cords when a head set is used to make voice conference. CONSTITUTION: A master set 32 is connected to plural pocket-sized slave sets 331 -33N through a radio channel and conference participants use headsets 481 -48N to take part in the conference. A channel 31 connecting to the master set 32 is used to make conference with other conference participants through a master set (not shown). The master set 32 sends a voice signal whose center frequency if f0 from a modulator 36 to the slave sets 331 -33N and they send voice signals whose center frequencies are f0 -fN different from each other to demodulators slave sets 371 -37N corresponding to the master set 32. Since each of conference participants is talked with each other by a radio channel, a cord tying the master set is not required.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voice conference apparatus for connecting a plurality of points to make a conference by voice.

[0002]

2. Description of the Related Art Of the audio conference devices that hold audio conferences,
For example, when some persons in the living room participate in a conference, these conference participants often hold a conference using a headset. This is because if a speaker hears the speech of another conference participant sent via the line, it may worsen the business environment of a person who is not participating in the conference.

FIG. 4 shows the configuration of a terminal device of a conventional audio conference apparatus using a headset. The terminal device 11 is connected to a conference partner (not shown) via a line 12. In this example, three wires 13 ₁ , 13 ₂ and 13 ₃ are drawn from the terminal device 11, and headsets 14 ₁ , 14 ₂ and 14 are respectively provided at the ends of these wires.
₃ is connected. Each of 14 ₁ , 14 ₂ and 14 ₃ is provided with a microphone 15 for inputting voice and a headphone 16 for outputting voice, and has a structure such that a human head holds them.

The audio signal 18 received from the line 12 is amplified by an amplifier 19 and the respective wires 13 ₁ , 1
Headsets 14 ₁ , 14 ₂ and 14 through 3 ₂ and 13 _3.
3 is supplied to the ears of the conference participants from the headphones 16. In addition, the voices of the individual conference participants are transmitted to the respective headsets 14 ₁ , 14 ₂ ,
The line 12 is input from the microphone 15 of 14 ₃ and mixed by the mixer 21 and further subjected to predetermined signal processing.
Sent to

[0005]

As described above, in the conventional audio conference apparatus, the headsets 14 ₁ , 14 ₂ and 14 _{3 in} which the microphone 15 and the headphone 16 are combined are connected to the conference terminal device 11 by the wires 13 ₁ and 13 _2. , 13 ₃ were connected. For this reason, the participants of the conference are restricted in their movement range by the length of the cords or the wires 13 ₁ , 13 ₂ , 13 ₃ . In addition, the wires 13 ₁ , 13 ₂ , 13 ₃
When the length of the headset is increased, the headset itself becomes heavy and bothersome because it is caught by other objects, entangled, and further pulled by the wires 13 ₁ , 13 ₂ , 13 ₃ .

SUMMARY OF THE INVENTION It is an object of the present invention to provide a voice conference device in which cords do not get in the way when a voice conference is held using a headset.

[0007]

According to a first aspect of the present invention, (a) a wireless transmitting means for wirelessly transmitting a voice of a conference participant as a voice signal and a voice of another conference participant. Each of the conference participants individually has a wireless reception means for wirelessly receiving a signal, and (b) is connected to the conference participants other than the conference participants who own these slaves by a line. Wired transmitting / receiving means for transmitting / receiving an audio signal via a line, and an audio signal obtained from this wired transmitting / receiving means are respectively transmitted to the wireless receiving means of the handset, while being transmitted from the wireless transmitting means of these handset. The audio conference apparatus is provided with a base unit having a wireless transmission / reception means for receiving the voice signal and transmitting it to the wired transmission / reception means.

That is, according to the first aspect of the present invention, since the parent device is connected to the line and the child device for the conference participants to input and output voice is wirelessly connected to the parent device, the child device side Such a code does not restrict the movement of the conference participants because it can move freely within the range where it can communicate with the base unit and there is no need to place a code between them.

According to a second aspect of the present invention, the slave unit of the first aspect of the invention has a wireless receiving means for receiving an audio signal of the same frequency from the master unit, and a frequency different from that of the master unit and for each slave unit. And wireless transmission means for transmitting audio signals at different frequencies.

As described above, according to the second aspect of the present invention, the frequency of transmitting the audio signal to the master unit is different for each slave unit.
It is possible to adjust the level of the voice signal of each person on the base unit side, or to block the input itself in order to prevent noise input from the microphone of a person who is not making a statement.

According to a third aspect of the present invention, the slave unit of the first aspect of the invention has a wireless receiving means for receiving an audio signal of the same frequency from the master unit, and is common to all slave units different in frequency from the master unit. Wireless transmission means for transmitting a voice signal at the frequency of.

As described above, according to the third aspect of the invention, since the voice signal for each slave unit is received by the master unit at the same frequency,
There is no need to mix these signals, as would be the case if they were received on separate frequencies.

According to a fourth aspect of the invention, the slave unit according to the second or third aspect of the invention has a built-in battery having a size to be accommodated in a pocket, and a microphone for inputting the voices of conference participants. It is characterized in that a headset having headphones for listening to the voices of other conference participants is connected to the headset.

As described above, according to the fourth aspect of the invention, since the child device is sized to be accommodated in the pocket, if the cordless handset is accommodated in the pocket of the jacket, the wire between the headset and the headset is for business activities. It will not cause any obstacles.

The invention according to claim 5 is characterized in that the slave unit according to the invention according to claim 3 transmits the audio signals of its own conference participants to the master unit in a time division manner.

As described above, in the invention according to the fifth aspect, since the slave unit transmits the voice signals of its own conference participants to the master unit in a time division manner, the voices of a plurality of conference participants are used using the same frequency. Can be adjusted independently on the master side.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments.

FIG. 1 shows the configuration of the audio conference apparatus on the terminal side according to an embodiment of the present invention. The terminal of the audio conference device is a master unit 32 connected to the line 31, and a plurality of slave units 33 ₁ , 33 ₂ , ...
... is composed of 33 _N. The line 31 may be an ISDN (Integrated Services Digital Network) other than an analog line and a digital line. Although not shown in the figure, a master unit of a conference participant is connected to the end of the line 31, and one or more slave units are wirelessly connected to this master unit.

By the way, the audio signal 3 received from the line 31
After being amplified by the amplifier 35, the signal No. 4 is input to the modulator 36 and modulated. Then, a radio wave is transmitted to each of the slave units 33 ₁ , 33 ₂ , ... 33 _N via an antenna (not shown). The modulator 36 of this embodiment has an oscillation frequency of 322.
MHz or less, and the electric field strength is 500μ at a distance of 3m
Generates radio waves below V / m. This is a necessary and sufficient output for use in a conference, and does not require a license because the output is small.

The master unit 32 includes slave units 33 ₁ , 33 ₂ , ...
33 _N number of demodulators 37 ₁ , 37 ₂ , ... 37
_N is provided. Corresponding slave units 33 ₁ , 33 ₂ , ...
The radio wave sent from 33 _N is received by an antenna (not shown), and these demodulators 37 ₁ , 37 ₂ , ...
The signals are separately demodulated at 37 _N and become voice signals. The mixer 38 is composed of an adder, and demodulators 37 ₁ , 37 ₂ , ...
The audio signals output from 37 _N are added and synthesized.

The output of the mixer 38 is input to a variable gain amplifier (AGC) 40 through a low pass filter (LPF) 39 and amplified. The low-pass filter 39 removes only high-frequency noise components unnecessary for normal conversation. This is because in the case where the number of conference participants is large, such a high-frequency noise component may occur when the inputs of many microphones are added and synthesized by the mixer 38, and this is removed. . This noise component is mainly composed of acoustic background noise and thermal noise generated from the resistance inside the amplifier.

The variable gain amplifier 40 is used to prevent the line 31 and the like from being damaged when the output of the mixer 38 becomes excessive in the case where the number of conference participants is large. There is. The variable gain amplifier 40 operates as a level limiter that automatically lowers the output level of the low-pass filter to a predetermined value or less when the output level of the low-pass filter reaches the level at which the trouble may occur. The output of the variable gain amplifier 40 is the line 3
1 will be sent.

On the other hand, each slave unit 33₁, 33₂, ...
… 33_NIs small and light enough to fit in your clothes pocket
Can be These cordless handsets 33₁, 33₂, ……
33 _NIs the sound generated by demodulating the radio waves emitted from the base unit 32 side.
Demodulator 41 for voice signal and power amplification of this voice signal
Power amplifier 42 for amplifying the sound to be transmitted
The amplifier 43, the modulator 44 for modulating the amplified voice, and
And a battery 45 for supplying electric power to each of these circuit devices.
It has and.

In addition, each child device 33₁, 33₂, ...
… 33_NA relatively short wire 47 ₁, 47₂, ... 4
7_NThrough the headset 48₁, 48₂, ...... 48_N
Are connected. These headsets 48₁, 48
₂, ...... 48_NHeadphones 49 and microphone 50
It is equipped. Microphone 50 has a condenser
A kurophone is used and its power source is
Doset 48₁, 48 ₂, ...... 48_NConnected to the child machine
33₁, 33₂, …… 33_NThe battery 45 of is used
Swelling. The headphones 49 are composed of speakers.
Has been established.

In the audio conference apparatus having such a configuration, the base unit 3
The modulator 36 on the second side has a single frequency f ₀Voice signal by radio wave
Is sent. Each child machine 33₁, 33₂, …… 33
_NThe demodulator 41 of converts this to a low frequency audio signal,
The sound is output from the headphones 49 after being amplified by the power amplifier 42.
I will be forced. The sound sent through the line 31 in this way
Voice signal is cordless handset 33₁, 33₂, …… 33_NOwn each
It is heard by people.

On the other hand, each slave unit 33 ₁ , 33 ₂ , ... 33 _N
The modulator 44 of these headsets 48 ₁ , 4
8 _2, .... 48 frequency respectively different audio signal amplified by the input amplifier 43 from the microphone 50 of the _N f _1, f _2, modulates a radio wave ... f _N. Base unit 32
Each of the demodulators 37 ₁ , 37 ₂ , ... 37 _N demodulates the audio signal of the corresponding frequency and converts it into an electric signal.

FIG. 2 is a block diagram of the voice conferencing device on the terminal side.
It shows the frequency allocation of the master unit and each slave unit.
It In the figure, the horizontal axis represents frequency and the vertical axis represents amplitude.
It The modulator 36 in the parent device 32 shown in FIG.
The center frequency f of the audio signal received from₀Modulate with. This
On the other hand, each slave unit 33₁, 33₂, …… 33_NModulation of
The center frequency of the sound to be transmitted is different from that of the instrument 44.
Frequency f₁, F ₂, …… f_NRadio wave is output
It Each of these frequencies f₀, F₁, F₂, …… f_NRadio wave
Is band-limited by the respective modulators 36 and 44.
Therefore, the bands do not overlap each other. Figure
Then, with respect to the baseband signal 51, each frequency f₀, F
₁, F₂, …… f_NRadio waves have higher and higher frequencies.
It is arranged so that Therefore, the line 31
The voice of the conference participant on the other side sent from the demodulator 37
₁, 37₂, ...... 37_NReceived by a different handset
The voice of 33 is the demodulator 37 of the base unit 32₁, 37₂, …… 3
7_NWill not be mixed and entered.

In this way, the demodulators 37 ₁ , 37 ₂ ,
The audio signal converted by 37 _N is sent to the line 31 through the mixer 38, the low-pass filter 39 and the variable gain amplifier 40 in this order.

In this embodiment, the mixer 38 is used to make each slave unit 3
Since the audio signals sent from 3 ₁ , 33 ₂ , ... 33 _N are mixed, it is possible to adjust the respective audio levels and send them to the line.

Modification

FIG. 3 shows a voice conference device according to a modification of the present invention.
It shows the configuration of the terminal. Base unit of this terminal
32A has one demodulator 37. Also, each cordless handset
33 ₁, 33₂, …… 33_NThe modulators 44 of the
One center frequency f₁The voice signal modulated by
It is outputting. The demodulator 37 receives these in common
It demodulates and outputs the audio signal as a low pass filter.
I'm trying to input directly to the filter 39.

In this way, each slave unit 3 has the same frequency f _1.
The form of receiving the audio signals of 3 ₁ , 33 ₂ , ... 33 _N may be a form in which the audio signals are simply mixed in an analog manner and received, or the respective slave units 33 ₁ , 33 3 are received.
₂ , ... 33 _N may determine the time zones to be received, and the radio waves of the same frequency f ₁ may be transmitted during the assigned time zones.

In the embodiment, each demodulator 37 ₁ , 3
The mixer 38 was placed directly after 7 ₂ , ... 37 _N ,
A low-pass filter 39 is arranged after each of the demodulators 37 ₁ , 37 ₂ , ... 37 _N , and a variable gain amplifier 40 is further provided.
May be separately arranged in the subsequent stage, and the mixer 38 may be arranged after that. As a result, it is possible to correct the difference in level of the audio signals sent from the respective slave units 33 ₁ , 33 ₂ , ... 33 _N and send the corrected signals to the line 31.

[0034]

As described above, according to the first aspect of the present invention, the master unit is connected to the line, and the slave unit for the conference participants to input and output voice is wirelessly connected to the master unit. Since the cordless handset can move freely within the range where it can communicate with the parent device, there is no need to place a cord between them, so such a cord restricts the movement of the conference participants. There is no.

Further, according to the invention as set forth in claim 2, since the wireless transmission means for transmitting the audio signal at the frequency different from the frequency of the master unit and different for each slave unit is provided, on the master unit side. It is also possible to adjust the level of the voice signal of each person, or to block the input itself in order to prevent noise input from the microphone of a person who is not making a statement.

Further, according to the third aspect of the invention, since the voice signal for each child device is received by the parent device at the same frequency, it is necessary to mix these signals, unlike the case where they are received at individual frequencies. Therefore, the structure of the device can be simplified and the cost can be reduced.

Further, according to the invention as set forth in claim 4, since the child device is sized so as to be accommodated in the pocket, if the cordless handset is accommodated in, for example, the pocket of the jacket, the wire between the headset and the office is clerical. It will not hinder their activities.

Further, according to the invention as set forth in claim 5, since the slave unit transmits the voice signals of its own conference participants to the master unit in a time-division manner, the same frequency is used for the plurality of conference participants. It becomes possible for the master unit to independently adjust the sound.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a configuration on a terminal side of a voice conference device according to an embodiment of the present invention.

FIG. 2 is a frequency characteristic diagram showing frequency allocation of the master unit and each slave unit on the terminal side of the audio conference apparatus of the present embodiment.

FIG. 3 is a schematic configuration diagram showing a configuration on a terminal side of a voice conference device in a modified example of the present invention.

FIG. 4 is a schematic configuration diagram showing a configuration of a terminal device of a conventional audio conference apparatus using a headset.

[Explanation of symbols]

31 lines 32,32A base unit 33 ₁ ~ 33 _N handset 36, 44 a modulator 37 and 41 demodulator 38 mixer 39 low pass filter 40 a variable gain amplifier 47 wire 48 headset 49 headphones 50 microphone

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H04M 3/56 H04M 3/56 Z

Claims (5)

[Claims] 1. Each conference has wireless transmission means for wirelessly transmitting the voice of a conference participant as a voice signal and wireless receiving means for wirelessly receiving the voice of another conference participant as a voice signal. Participants have their own handsets, and a wired transmission / reception means for connecting and receiving audio signals via the lines that are connected to conference participants other than the conference participants who own these handsets, and this wired transmission / reception. Wireless transmission / reception means for transmitting the audio signals obtained from the respective means to the wireless reception means of the slave unit, and receiving the audio signals transmitted from the wireless transmission means of these slave units and sending them to the wired transmission / reception means. A voice conferencing apparatus comprising: a base unit having a. 2. The cordless handset has a radio receiving means for receiving an audio signal of the same frequency from the parent device, and a radio transmission means for transmitting an audio signal at a frequency different from that of the parent device and different for each child device. The audio conference apparatus according to claim 1, further comprising: 3. The wireless unit receives wireless signals of the same frequency from the base unit, and wireless transfer unit transmits audio signals at a frequency common to all the remote units different from the frequency of the base unit. 2. The method according to claim 1, further comprising:
The audio conference device described. 4. A head having a built-in battery in a size that can be accommodated in a pocket of the child device, each of which has a microphone for inputting a voice of a conference participant and a headphone for listening to a voice of another conference participant. 4. The audio conference device according to claim 2, wherein the set is connected to the set. 5. The audio conference apparatus according to claim 3, wherein the child device transmits the audio signals of its own conference participants to the parent device in a time division manner.