JPH07193800A - Communication conference system - Google Patents

Abstract

PURPOSE:To attain a distributed conference system high in utilization ratio of a transmission line enabling many users to attend a conference using a comparatively small number of comparatively short lines. CONSTITUTION:The conference system is provided with a spatial propagation equipment 50 for converting a video signal and a sound signal into a radio wave or an optical signal and transmitting/receiving the signal, a line collecting equipment 40 for selectively synthesizing a video signal obtained from the equipment 50 and selectively adding a sound signal, a connection controller 20 for sending the video signal and the sound signal from the equipment 40 to a communication network, and intermultipoint communication controller 30 for selectively synthesizing video signals from many connection controllers 20 and selectively adding sound signals to control a communication conference.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multimedia communication conference system including video and audio.

[0002]

2. Description of the Related Art In the conventional communication conference system, a person mainly connecting a conference room between two points via a wide area network.
This system configuration is, for example, as shown in FIG.
A communication terminal device having an image system including a camera 903 and a television 902 capable of capturing images of a plurality of participants and displaying the images, and an audio system including a microphone 906 and a speaker 904 for capturing and reproducing the utterances of the plurality of participants. 90
Are basically connected by a wide area network 960. Camera 9
Participants can be captured by 03, the other participants can be displayed on the TV 902, and opinions and discussions can be exchanged using the microphone 906 and the speaker 904. This allows you to hold a immersive conference even when you are far away, saving you the cost and time of attending the conference. Here, the connection control device 901 is a device that controls these elements. Such systems are connected via a communication network (wide area network) 960 such as an INS network, so that a conference can be held even if they are separated from each other.

One of the problems with such a conventional teleconferencing system is that it must be assembled in a conference room during a conference. Normally, there is only one such conference room in one business office, the living room and the conference room are separated, and it is troublesome to manage the conference room and exchange keys, and you can use the telephone to talk from your seat to a distance. It is inconvenient when compared to that It is also difficult for participants from three or more business sites to attend the conference at the same time.
Also, the number of people who can participate in the conference room is at most 10. FIG. 15 shows a configuration example of a conference room of a conventional remote conference system.

In order to solve this inconvenience, a distributed conference system as shown in FIG. 16 has been devised in which each conference participant is assigned a conference terminal. In this system, the multimedia conference terminals 910-1 to 910-3 handling voice, video, text data, etc. are connected to the connection control device 920-.
1 to 920-3 and is connected to the communication network 960.
The multipoint communication control device 930 is the connection control device 920-1.
To 920-3 are connected in a star shape using a communication network such as an optical fiber cable. The transmission of multimedia data such as voice, video and text data is performed by ATM (Asy
B-ISDN (Broadband Int) using nchronous Transfer Mode technology
integrated Services Digital
It is efficiently transmitted by the Network technology. Figure 1
FIG. 17 shows an example of the display on the display 911 of the conference terminal in the distributed conference system shown in FIG.

By the way, there are members who frequently speak and members who speak only occasionally and listen to the conference. Therefore, if the usage distribution and processing of the transmission paths are divided into groups so that the members who frequently speak can be provided with the transmission paths as much as possible, the transmission paths can be used efficiently. However, in the distributed conference system shown in FIG. 16, the multimedia conference terminals 910-1 to 910-3 are connected to the connection control devices 920-1 to 920-3 on a one-to-one basis. Therefore, in order to increase the number of participants in the conference, it is necessary to increase the number of connection control devices, which naturally limits the number of participants in the conference, and the number of connectable terminals is at most 1.
The conference service can be provided only to 0 conference participants and 10 conference participants. Further, since the connection control devices 920-1 to 920-3 and the multipoint communication control device 930 also require connection of optical fiber cables, the number of optical fiber cables increases as the number of conference participants increases. Thus, even if the conference participants are not too far apart from each other, for example, in the same room or on the same floor, in order to provide services to the terminals, the connection control devices 920-1 to 920-3 need to be connected to the multipoint communication control device 930. You have to pull out the fiber optic cable. Therefore, in order to hold a communication conference with a large number of people, it is necessary to add an optical fiber cable and a connection control device, which increases the cost required for the equipment.

[0006]

As described above, in the conventional conference room type remote conference system, it is necessary for the conference participants to gather in the conference room, and in the distributed conference system using the conference terminals, Equipment and expenses were involved in laying optical fiber cables, etc., and the number of participants in the conference was limited, and the line usage efficiency was also poor.

An object of the present invention is to solve these problems and to realize a distributed conference system with a small number of lines and a relatively short line, in which a large number of users can participate and which has good line use efficiency.

[0008]

[Means for Solving the Problems] In a teleconference system in which a plurality of conference participants hold a teleconference between multiple points by connecting conference terminals that handle multimedia information including video signals, audio signals and data through a communication network. , A spatial propagation device that converts a video signal and an audio signal into a radio wave or an optical signal and transmits / receives the signal, a concentrator that selectively synthesizes the video signal from the spatial propagation device, and selectively adds an audio signal, and an image from the concentrator A connection control device for transmitting signals and audio signals to a communication network; and a multipoint communication control device for controlling a communication conference by selectively synthesizing video signals from a large number of connection control devices and selectively adding audio signals. Equipped with.

Further, the video signal subjected to the selective combining process and the audio signal subjected to the selective addition process by the multipoint communication control device are transmitted to the connection control device via the communication network, and the video signal and the audio signal are transmitted to a large number of spatial propagation devices. And means for providing a communication conference service to a large number of conference terminals.

Further, a plurality of connection control devices are divided into several groups, a communication line required for each group is connected to a multipoint communication control device, and a video signal and an audio signal are provided for each of the divided groups. Try to process the signal.

[0011]

According to the present invention, it is possible to realize a distributed conference system with a relatively small number of lines and a relatively short number of lines, in which a large number of users can participate, and in which the transmission line is used efficiently, Cost can be made economical. Further, by dividing the conference participants into groups, the transmission line can be used more efficiently.

[0012]

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

FIG. 1 is a diagram showing the configuration of a distributed conference system according to an embodiment of the present invention.

This system comprises a multipoint communication control device 3
0, the connection control devices 20-2 and 20-3 that can directly accommodate the conference terminals 10-1 and 10-2, and the terminals 10-3 to 10-10.
-5 or from the connection control device 20-1 to the terminal 10-
Video / audio text data transmitters / receivers 50-1 to 50, which are space propagation devices for converting signals such as audio / video / text data to 3 to 10-5 into radio signals on radio waves for transmission / reception
-4, a concentrator 40 for selectively synthesizing media such as images, voices, and text data sent from a number of spatial propagation devices shells, and an image, a sound selectively synthesized and output by the concentrator 40, A connection control device 20-1 for outputting a signal such as text data to the communication network 60;
Is configured as an element. As the communication network 60 to which the multipoint communication control device 30 and the connection control devices 20-1, 20-2, 20-3 are connected, an ATM wide area network such as B-ISDN, or an ATM-LAN (a local network). ATM-Loc
alArea Network) and STM (Synch)
It is possible to use a multimedia transfer LAN (ronous Transfer Mode).

FIG. 2 shows an example of the installation state of the conference terminals in this embodiment. The conference terminal 10 includes a video system including a camera 103 and a terminal body 101, a microphone and a speaker 10.
4 or a sound system composed of headphones and a spatial propagation device (a video / audio text data transceiver 50 in the figure) and the like.

The image from the camera 103 and the sound from the microphone are temporarily collected in the concentrator 40 via the space propagation device 50, and then via the connection control device 20-1 and the communication network 60, multipoint communication at a distance. It is sent to the control device 30.
The video and audio are selectively combined, and the conference terminals 10-1 to 10-1 connected to the connection control devices 20-1 to 20-3 are connected.
10-5, so that each conference participant can hear the voices of other participants and can see the video. The conference terminal 10 is composed of a connection device and a workstation or personal computer connected to the connection device. The workstation or personal computer has a built-in video board, and the connection control devices 20-1 to 20-3
The video transmitted from the terminal 10-1 or 10-2 directly to the terminal 10-1 or 10-2, or the video transmitted from the space propagation device 50 to the terminal 10-3 to 10-5 can be displayed in the window of the screen.

As a result, the terminals 10-1 and 10-2 can hold a communication conference via the connection control devices 20-2 and 20-3 and the multipoint communication control device 30, and the terminal 10-3 below the concentrator 40. 10-5 can also receive the conference service.

Further, in the case of the terminals 10-1 and 10-2, the multipoint communication control unit 30 divides the conference participants into two groups according to the degree of participation in the conference, and the conference terminals 10-1 and 10-2.
10-2 is divided into a paneler terminal and a floor terminal. As a device that sets the communication line for each group according to the attribute of the group to which it belongs and processes the video and audio for each group, it has a function to support the requests from the panel group and floor group. ing. For the processing of the panel group, the call control unit 303 of the multipoint communication control device 30 is connected to the connection control devices 20-2 and 2-2.
For communication with 0-3, each terminal 10-
Set every 1 and 10-2. On the other hand, for processing the floor group, a unidirectional distribution downlink is set between the connection control devices 20-2 and 20-3, and a floor terminal is set to a multi-destination broadcast distribution line. Then, if a floor terminal makes a message such as a question, an uplink is set up from any terminal.

FIG. 3 shows the configuration of the multipoint communication control device 30.

The line I / F unit 304 connects the device to the communication network 60.
Its main function is to interface with, and it also has the function of converting each media to ATM. The video processing unit 301 performs reduction processing by pixel thinning, composite processing of a plurality of video signals, video selection processing, and the like. The voice processing unit 302 performs N-1 addition processing for removing only the own voice from the voice signal from each terminal 10 and adding, loss insertion processing corresponding to the number of added signals, speaker detection processing, and overload processing. The signal after the addition is distributed to the terminals 10 connected to the respective connection control devices 20. Furthermore, the data processing unit 310
Has a data transmission / reception function and performs control communication by performing a statement process in response to a statement request from each terminal 10.
The control unit 311 manages the conference.

At the start of the conference, the call control unit 303 sets a one-way video / audio downlink for the floor group,
A communication network 60 is provided between the multipoint communication control device 30 and each terminal 10.
Set up a tree-shaped distribution line using the copy function in. On the other hand, if the floor group terminal wants to ask a question during the conference, the terminal sets up a data line from the data processing unit 310 and requests a speech, and in response to this, the multipoint control unit 30 receives the speech request. Statement control is performed to select a statement from any one of them. Then, a rising video / audio line is set between the terminal and the multipoint control unit 30, and a video signal from the selected terminal is transmitted to the video processing unit 301 and an audio signal is transmitted to the audio processing unit 302. Processing of video synthesis, switching, or audio addition is performed for each. Thereafter, these signals are transmitted from the video processing unit 301 and the audio processing unit 302 to each terminal and distributed. Between the multipoint communication control device 30 and the floor group connection control device 20, normally only a downward unidirectional line to the terminal 10 side is set. However, if necessary, the terminal 10 may ask a question or the terminal 10 may In order to participate in the debate, all the terminals 10 are connected in order to go up from the terminal 10 to the multipoint control unit 30 via the connection control unit 20 and individually set up a line, or to collect opinions from the terminals 10. It is possible to collect information at once by setting an upward unidirectional simultaneous line to the multipoint communication control device 30 side. As a result, the participants of the floor group terminal usually listen and hear the situation of the conference at the conference terminal, and also communicate with each other between the floor group terminals, but get the right to speak when necessary. You can ask questions, or participants in all terminals can participate in the vote.

Although the conference terminal 10 is divided into two groups in advance in this description, it is also possible to transfer the group to which the terminal belongs while the conference is in progress. Further, the multipoint communication control device 30 is based on the frequency of speech during the conference.
It is also possible to change the group affiliation of each terminal under the control of the side and replace the members.

FIG. 4 shows the configuration of the connection control device 20.

The line I / F unit 206 is a video transmission / reception unit 201.
Video signal from the audio signal from the audio transceiver 202,
Call control data from the call control unit 203, data transmission / reception unit 2
The data from 04 is received, multiplexed in an ATM cell, and transmitted to the multipoint control unit 30 via the communication network 60. On the contrary, the signal from the multipoint communication control device 30 is received via the communication network 60, each signal is separated, and the video transmission / reception unit 201, the voice transmission / reception unit 202, and the call control unit 2 are separated.
03, the data transmission / reception unit 204.

The connection control device 20 is the group B in FIG.
When the connection is the same as the terminal 10-1 of the terminal 10 or the terminal 10-2 of the group C, the video transmitting / receiving unit 201 is connected to the video board built in the terminal 10 and the camera 103, and the NTSC from the camera 103 is connected. The signal is digitized and sent to the line I / F unit 206. Further, the signal from the line I / F unit 206 is converted into an analog signal and sent to the video board built in the terminal 10. The voice transmitting / receiving unit 202 performs encoding / combining processing of a voice signal connected to the microphone and the speaker 104, and performs transmission / reception processing with the line I / F unit 206. The data transmission / reception unit 204 is connected to the terminal 10 and receives data from the terminal 10 from the multipoint communication control device 30.
The data stored in the multipoint control unit 30 can be sent to the terminal 10.

On the other hand, in the connection control device 20-1 connected to the concentrator 40 belonging to the group A, the video transmission / reception unit 20
1, the voice transmitting / receiving unit 202, and the data transmitting / receiving unit 203 are connected to the concentrator 40, and video, voice, and data signals are distributed to each terminal 10-3 to 10-5 via the video / voice / text data transceiver 50. To be done. In addition, the terminal 10-
The video, audio and data signals from 3 to 10-5 are transmitted by the video / audio / text data transmitter / receiver 50 to the concentrator 4.
The data are collected into 0 and subjected to a selective synthesizing process on the voice and the video, and then sent to the multipoint control unit 30.

The call control unit 203 supports control / monitoring of the line I / F unit 206 and connection control of video, voice and data to the line. The control unit 205 is the control highway 2
08 via the video transmission / reception unit 201 and the audio transmission / reception unit 2
02, the call control unit 203, and the data transmitting / receiving unit 204, and manages each.

5 to 8 show the functions of the video / audio / text data transmitter / receiver 50 shown in FIG. 1 separately for the transmitter and the receiver.

FIG. 5 shows the structure of a video / audio / text data transmitter used on the side of the terminals 10-3 to 10-5. Video / audio / text data transmitter is camera 103
Video signal input from (conference participant's own video signal)
After being amplified by the image amplifier 501, the image carrier generator 50 is generated according to the frequencies f4, f5, and f6 used in each device.
4 and AM modulator 503. Also microphone 10
The voice from the No. 6 is amplified by the voice amplifier 506 and is modulated by the voice carrier generator 508 and the FM modulator 507. Further, the text data from the terminal body 101 is modulated by the data carrier generator 510 and the FM modulator 509. Then, the AM-modulated video signal, the FM-modulated audio signal, and the text data are mixed and combined by the mixing and composing device 505, and the image / audio / signal connected to the concentrator by the antenna 511 as a radio wave radiator. Send to text data receiver.

FIG. 6 shows the configuration of a video / audio / text data receiver used on the side of the terminals 10-3 to 10-5. The video / audio / text data receiver is the concentrator 40.
Receives video / audio / text data from the video / audio / text data transmitter connected to. The received video, audio, and text data are sent to the multipoint control unit 3
0 processed downlink. That is, the video signal is a combination of the video signal sent from another terminal and the video signal from the terminals 10-3 to 10-5 connected below the concentrator 40, and again the multipoint communication control device 3 is processed.
0 is selected and synthesized, and the audio signal is obtained by adding the audio signal sent from another terminal and the audio / video signal from the terminals 10-3 to 10-5 connected below the concentrator. The multipoint communication control device 30 performs selective addition processing again. In the receiver, since the tuner 512 performs high frequency amplification and frequency conversion and then extracts video, audio, and text data, the video intermediate frequency amplification 513, the audio intermediate frequency amplification 515, and the text data intermediate frequency amplification 5
After performing step 18, the detection circuits 514, 516, and 519 perform AM detection on the video signal and FM detection on the voice and text data to extract the video signal, voice signal, and text data. After the video signal is extracted, it is input to the video controller board built in the terminal body 101 and displayed on the display. The audio signal is output to the speaker 104 or headphones. Further, the text data is converted into a level corresponding to a terminal interface such as RS-232C and output to the terminal body 101.

FIG. 7 shows the configuration of a video / audio / text data receiver installed on the side of the concentrator 40. This video / audio / text data receiver is used for terminals 10-3 to 10-3.
Receives video, audio, and text data that has passed through the video / audio / text data transmitter from -5.

The received video, audio, and text data are subjected to a synthesis process and an addition process in the concentrator 40, and are then sent to the communication network 60 by the connection control device 20-1 as a line to be transmitted to multiple points. It is processed by the inter-communication control device 30. That is, in the case of video, the video signal sent from another terminal and the terminal 10 connected below the concentrator 40
-3 to 10-5, if the video signal is voice, an audio signal transmitted from another terminal and an audio signal from the terminals 10-3 to 10-5 connected to the concentrator 40 and below. To receive. These signals are high-frequency amplified and frequency-converted by the tuner 512, and then video intermediate frequency amplification 513, audio intermediate frequency amplification 515, and text data intermediate frequency amplification 518 are performed in order to extract video, audio, and text data. After that, the video signal is AM detection, voice,
The text data is FM-detected, and the video signal, the audio signal, and the text data are extracted.

FIG. 8 shows the structure of a video / audio / text data transmitter installed on the concentrator 40 side. From the multipoint communication control device 30 to the terminals 10-3-1 through the communication network.
Send video, audio and text data to 0-5. The transmitter transmits the video signal, which is output from the connection control device 20-1 to the concentrator 40 and represents the conference participants themselves, to the video amplifier 501.
After being amplified by, the video carrier generator 504 and the AM modulator 503 perform modulation according to the frequency used in each device.
Further, the voice output from the connection control device 20-1 to the concentrator 40 is amplified by the voice amplifier 506 and modulated by the voice carrier generator 508 and the FM modulator 507. In addition, the text data from the terminal body 101 is transmitted to the data carrier generator 5
10 and the FM modulator 509. Then AM
The modulated video signal, the FM-modulated audio signal and the text data are mixed and combined by the mixing and composing device 505, and the video / audio / text data receiver connected to the terminal side by the antenna 511 as a radio wave radiator. Send.

FIG. 9 shows the structure of the image section 401 of the concentrator 40. The video section 401 is composed of an AD conversion section 4011, a video selection / combination section 4012, a frame synchronization section 4013, and a DA conversion section 4014, which is transmitted by radio waves or light from the terminals 10-3 to 10-5 and is propagated in space. The video signal output from the video / audio / text data transmitter / receiver 50-1 as an apparatus is input and synchronized as an NTSC or RBG video signal to synthesize the video signal. When synthesizing, a video is selected to determine from which terminal the video signal is to be displayed on one synthesizing screen. For example, the terminal 10-3
Or only the video from the terminal is displayed, or the terminals 10-3 to 10-
The control is performed such that the images from 5 are combined and displayed on one screen.

FIG. 10 shows the configuration of the image selection / synthesis unit 4012 in the image unit 401 of the concentrator 40.

The video signal digitized by the AD conversion unit 4011 and output from the frame synchronization unit 4013 is decided by the video selection control signal by the video selection unit 40121, and the screen for the synthesis is displayed. After being size-converted through a size conversion filter (consisting of both vertical and horizontal filters) 40122 for changing the size of, and once stored in the size conversion memory 40123,
It is output as a combined video signal. The combined video signal is DA converted and returned to an NTSC signal, then input from the concentrator 40 to the connection control device 20-1, further interfaced with the communication network 60, and transmitted to the multipoint communication control device 30. To be done.

FIG. 11 shows the structure of the frame synchronization unit 4013 in the video unit 401 of the concentrator 40.

Video / audio / text data transmitter / receiver 50
-1, the video signals received from the terminals 10-3 to 10-5 need to be processed once after being synchronized because the phases of the horizontal synchronizing signal and the frame synchronizing signal are independent. Therefore, when writing to the size conversion memory 40123, the received clock and frame pulse F
Address control is performed using 2V so that writing is performed. Further, at the time of reading, the internal clock synchronized with the communication network 60 in the concentrator 40 and the internal F2V are used for reading. At this time, the synchronous memory 40132-1 to
For the address control of 40132-3, it is necessary to prevent the received F2V pulse and the internal F2V pulse from having the same value and colliding. Therefore, when a collision occurs, the memory address jump control is performed so as to avoid it.

FIG. 12 shows the voice addition unit 402 of the concentrator 40.
Shows the configuration of.

The voice addition unit 402 is an A / D conversion unit 402.
1, the reception buffer 4022, and the audio signal from each terminal 10-3 to 10-5 is AD as in the case of video.
After the conversion, the delay is adjusted and the STM-multiplexed voice signal is transmitted to the connection control device 20-1.

The multimedia conference terminal 10 realized by the present invention displays a conference screen and text data on a large number of windows. A moving image display and a still image display are possible on this screen.

FIG. 13 shows a display example on the display of the terminal of the multimedia conference system realized by the present invention.

In FIG. 13, terminals 1 and 2 (10-1, 10)
-2) is the image that has been selectively combined by the multipoint control unit 30, and the terminals 3, 4 and 5 (1
The images of group A from 0-3 to 10-5) are the images that have been selectively combined by the line concentrator 40 and then selectively combined by the multipoint communication control device 30. In the video synthesizing process, if the cutout position and the display position are fixed, the process can be easily executed only by the size changing process.

As described above, in the case of providing a service to the conference participant terminals 10 that are in the same room, on the same floor, or the like and are separated from each other by only a few meters or a dozen meters, video, audio, etc. are converted into radio waves or optical signals. A space propagating device for transmitting and receiving is provided, and signals from this space propagating device are collected by the concentrator 40. At this time, each terminal 1
Signals from 0 use radio waves of different frequencies, and the radio field strength is selected according to the distance. Also,
If the concentrator 40 reproduces, selects, and synthesizes the signals and sends them to the connection controller 20, the multipoint-to-point communication controller 30 can process them as one group.

[0045]

As described above, a communication conference in which a plurality of conference participants conduct a communication conference between multiple points by connecting conference terminals that handle multimedia information including video signals, audio signals and data through a communication network. The system includes a space propagation device that converts a video signal and an audio signal into a radio wave or an optical signal and transmits / receives the signal, a concentrator that selectively synthesizes the video signal from the space propagation device, and performs a selective addition process on the audio signal. Multipoint communication control for controlling a communication conference by selectively combining and processing the video signals from a large number of connection control devices and the connection control device that sends the video and audio signals of the above to the communication network. A multipoint communication control device, and transmits the video signal selected and synthesized by the multipoint communication control device and the audio signal processed by the selective addition process to the connection control device via the communication network. Distributes the signal into a number of space propagation devices. Thus provide teleconference services to many of the conference terminal, using a relatively small, relatively short lines,
It is possible to realize a distributed conference system in which a large number of users can participate and which uses the transmission line efficiently, and it is possible to reduce the equipment cost.

Further, by dividing the conference participants into several groups and connecting the communication lines required for each group to the multipoint communication control device, the transmission line can be used more efficiently. it can.

[Brief description of drawings]

FIG. 1 is a configuration of an embodiment of a communication conference system of the present invention.

FIG. 2 is an example of installation of a terminal of the communication conference system shown in FIG.

FIG. 3 is a configuration of a multipoint communication control device of the communication conference system shown in FIG.

FIG. 4 is a configuration of a connection control device of the communication conference system shown in FIG.

5] Video / audio / of the communication conference system shown in FIG.
The configuration of the terminal side transmitter of the text data transceiver.

FIG. 6 is a video / audio / video of the communication conference system shown in FIG.
Configuration of the terminal-side receiver of the text data transceiver.

FIG. 7 is a video / audio / video of the communication conference system shown in FIG.
The configuration of the receiver on the concentrator side of the text data transceiver.

FIG. 8 is a video / audio / video of the communication conference system shown in FIG.
Constitution of the concentrator side transmitter of the text data transceiver.

FIG. 9 is a configuration of a video unit of the concentrator of the communication conference system shown in FIG.

10 is a configuration of a video selection / synthesis unit of the video unit shown in FIG.

11 is a configuration of a frame synchronization section of the video section shown in FIG.

12 is a configuration of a voice addition unit of the concentrator of the communication conference system shown in FIG.

FIG. 13 is a display example on the display of the terminal of the communication conference system shown in FIG.

FIG. 14 is a basic configuration of a conventional remote conference system.

FIG. 15 is a configuration of a conference room of a conventional remote conference system.

FIG. 16 is a basic configuration of a conventional distributed conference system.

FIG. 17 is a display example on a display of a terminal of a conventional distributed conference system.

[Explanation of symbols]

10, 910 Conference terminal 20, 920 Connection control device 30, 930 Multipoint communication control device 40 Concentrator 50 Video / audio text data transmitter / receiver 60, 960 Communication network 101 Terminal body 102 Keyboard 103, 903 Camera 104, 904 Speaker 106, 906 Microphone 201 Connection control device Video transmission / reception unit 202 Connection control device Audio transmission / reception unit 203 Connection control device Call control unit 204 Connection control device Data transmission / reception unit 205 Connection control device control unit 206 Connection control device Line I / F unit 208 Connection control device control Highway 301 Multipoint communication control device Video processing unit 302 Multipoint communication control device Voice processing unit 303 Multipoint communication control device Call control unit 304 Multipoint communication control device Line I / F unit 310 Multipoint communication control device Data processing unit 311 Multipoint communication Control device control unit 401 Concentrator device video unit 402 Concentrator device audio addition unit 501 Video audio text data transceiver Video amplifier 502 Video audio text data transceiver Sync signal generator 503 Video audio text data transceiver AM modulator 504 Video audio text data Transceiver Video carrier generator 505 Video / audio text data transceiver Mixed synthesizer 506 Video / audio text data transceiver Audio amplifier 507 Video / audio text data transceiver Audio FM modulator 508 Video / audio text data transceiver Audio carrier generator 509 Video / audio Text data transceiver Text data FM modulator 510 Video audio text data transceiver Text data carrier generator 511 Video audio text data transceiver Antenna 512 Video audio text data transceiver Tuner 513 Video audio text data transceiver Video intermediate frequency amplifier 514 Video audio text data transceiver Video detector 515 Video audio text data transceiver Audio intermediate frequency amplifier 516 Video audio text data transceiver Audio FM detector 517 Video audio text data transceiver Low frequency amplifier 518 Video / audio text data transceiver Text data Intermediate frequency amplifier 519 Video / audio text data transceiver Text data FM detector 520 RS232C level converter 901 Connection control device 902 TV 905 Facsimile 907 Electronic blackboard

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuo Une 1-6-1, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation

Claims (3)

[Claims] 1. A communication conference system in which a plurality of conference participants hold a communication conference between multiple points via a communication network, the conference terminal handling multimedia information consisting of a video signal, an audio signal and a data signal. A spatial propagation device for converting a voice signal and a data signal into a radio wave or an optical signal for transmission and reception, and a video signal from the spatial propagation device is selectively combined and processed, a voice signal is selectively added, and a data signal is accumulated and distributed. A concentrator, a connection control device for sending out video signals, audio signals and data signals from the concentrator to a communication network, and a process of selectively synthesizing video signals from a plurality of the connection control devices and accumulating and distributing data signals. And a multipoint communication control device for controlling a communication conference by selectively adding and processing voice signals. . 2. The video signal which is selectively combined and processed by the multipoint communication control device, the audio signal which is selectively added and the accumulated data signal are transmitted to the connection control device through a communication network, and the video signal and the audio signal are transmitted. 2. The communication conference system according to claim 1, further comprising means for distributing a signal and a data signal to a large number of the space propagation devices and providing a communication conference service to a large number of conference terminals. 3. A plurality of the connection control devices are divided into several groups, a communication line required for each group is connected to the multipoint communication control device, and a video signal is provided for each of the divided groups. 3. The communication conference system according to claim 1, further comprising processing an audio signal.