JPH09200213A - Audio information transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve transmission efficiency by transmitting an audio cell while using an asynchronous transfer mode(ATM) network. SOLUTION: A sound/silence detection part 3 discriminates the sound/silence of audio frame and discriminates the head 1 end of sound information. A status adding function part 4 adds head/end information from the sound/silence detection part 3 to data for one cell from an assembly buffer 2. An SN part 5 generates the pay-load section of the cell by adding a sequence number to the data to which the head/end information is added. A header adding function part 6 generates an ATM cell, for which a header is added to the pay-load section of the cell, and sends it out to the ATM network. An additional information monitoring function part 9 detects the head/end information in the pay-load section of the cell received from the ATM network through a header check part 8 and corresponding to that detected result, an SN check part 10 and a delay fluctuation absorption buffer 11 are controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voice information transmission system, and more particularly to an ATM (Asynchronous T) system.
AAL (AT) in transfer mode technology
M Adaptation Layer) Type 1 S
AR (Segmentation And Rease)
The present invention relates to a voice cell transmission device having a mamble subscriber) processing function.

[0002]

2. Description of the Related Art Conventionally, in a voice cell transmission apparatus of this type, a transmitter has a voice / non-voice detection function for voice information including voiced information and silence information, and a voice stored in a transmission data buffer. When the information is determined to be voiced information by the voiced / non-voiced detection function, the head information or the tail information of the voiced information and the sequence number are added to the cell header and the cell is transmitted.

When the voice information stored in the transmission data buffer is determined to be the silence information by the voice / silence detection function, the information indicating the silence is added to the cell header of the first cell,
The top cell is being sent.

Further, the receiving section has a function of reproducing voiced information and reproduction of silent information based on the additional information added in the header of the received cell.

In this voice cell transmission apparatus, the transmitter unit packetizes voice information for each basic unit to generate a voice cell, detects whether the generated voice cell is a voice cell or a silent cell, and transmits the cell. Are in control.

In the case of a voiced cell, the head cell and the tail cell are respectively detected, the head / tail information is added to the cell headers of those cells, and the sequence numbers are added to the cell headers of all the voiced cells.

In the case of a silent cell, information indicating silence information is added to the cell header of the leading silent cell, and the leading silent cell is transmitted.

In the receiving section, based on the additional information added in the cell header of the received cell, the voiced cells are decomposed and cell interpolation is performed at the time of discarding the cells to reproduce the voiced information and receive the silent cells. The silent cell is played until the voiced cell is received and the silent information is played back. The above-mentioned voice cell transmission device is described in detail in Japanese Patent Laid-Open No. 5-244201.

[0009]

In the above-mentioned conventional voice cell transmission apparatus, since the head / tail information, sequence number information and silence information are defined in the cell header, the voice cell is transmitted using the ATM network. Can not do it.

Further, since one cell of the leading silent cell of the silent information is transmitted in order to recognize the silence, the number of cells on the transmission path is increased as compared with the case of only the voiced cells, and the transmission efficiency is lowered. I will end up.

Therefore, an object of the present invention is to solve the above problems and provide a voice information transmission system capable of transmitting voice cells using an ATM network and improving the transmission efficiency. is there.

[0012]

In a first voice information transmission system according to the present invention, voice information including a voiced portion and a voiceless portion is transferred to a cell including an information field which is a user information storage portion and a header portion. A voice information transmission system comprising: a transmitting device for converting and transmitting; and a receiving device for receiving the cell and reproducing the voiced part and the silent part from the cell, wherein the beginning and the end of the voiced part. The transmitting device is provided with a detecting means for detecting the above and an adding means for adding in the information field additional information indicating each of the beginning and the end of the voiced portion detected by the detecting means.

The second voice information transmission system according to the present invention has, in addition to the above-mentioned structure, a voiced / non-voiced detection means for detecting the voiced portion and the voiceless portion, and the voice / non-voice detection means to output the voiceless sound. The transmitting device comprises means for suppressing transmission of the cell when a portion is detected.

In the third voice information transmission system according to the present invention, the voice information including the voiced portion and the voiceless portion is converted into a cell including an information field and a header portion, which is a storage portion of user information, and is transmitted. A voice information transmission system including a device and a receiving device for receiving the cell and reproducing the voiced part and the silent part from the cell, the voice information transmission system being added in the information field received from the transmitter. Additional information detecting means for detecting additional information indicating the beginning and the end of the voiced portion, a checking means for checking the sequence number of the header portion according to the detection result of the additional information detecting means, and the checking means The means for reproducing the voiced portion according to the check result, and the means for reproducing the silent portion according to the detection result of the additional information detecting means are provided. It is provided on a communication apparatus.

In a fourth audio information transmission system according to the present invention, in the above-mentioned configuration, the means for reproducing the silent portion detects the additional information indicating the end of the voiced portion by the additional information detecting means. The silent portion is reproduced until the cell to which the additional information indicating the head of the voiced portion is added can be reproduced.

In the fifth voice information transmission system according to the present invention, the voice information including a voiced portion and a voiceless portion is converted into a cell including an information field and a header portion, which is a user information storage portion, and is transmitted. A voice information transmission system, comprising: a device; and a receiving device that receives the cell and reproduces the voiced part and the silent part from the cell, the detection means detecting the beginning and end of the voiced part. And the additional information added to the information field, the additional information adding means for adding additional information indicating the beginning and the end of the voiced portion detected by the detecting means in the information field, and the additional information added in the information field. Of additional information detecting means for detecting the sequence number of the header portion according to the detection result of the additional information detecting means, Means for reproducing said sound part according to Ekku result, and means for reproducing the silence according to a detection result of the additional information detection means includes the receiving device.

In addition to the above structure, the sixth voice information transmission system according to the present invention has a voice / sound detection means for detecting the voiced portion and the voiceless portion, and the voice / voiceless detection means for the voiceless / soundless portion. The transmitting device comprises means for suppressing transmission of the cell when a portion is detected.

In a seventh audio information transmission system according to the present invention, in the above-mentioned structure, the means for reproducing the silent portion detects the additional information indicating the end of the voiced portion by the additional information detecting means. The silent portion is reproduced until the cell to which the additional information indicating the head of the voiced portion is added can be reproduced.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the operation of the present invention will be described below.

The present invention has the following functions based on the fact that the AAL type 1 is adopted to perform the transmission by the ATM cell so that the voice cell can be transmitted by using the ATM network. .

The transmitting side is provided with a detection function for detecting voiced / non-voiced information of voice information when generating a cell, and information indicating the head of the voiced information in the payload of the cell at the head of the voiced cell. To generate a cell by adding information indicating the end of the voiced information to the payload of the cell at the end of the voiced cell. At that time, add a sequence number to each cell,
Only voiced cells are sent out.

On the receiving side, a sequence number check is performed on the basis of the additional information of the received cell, cell interpolation is performed when cell loss is detected, and voice information is reproduced. Further, when reproducing the silent information on the receiving side, the reproduction of the silent information is started after the cell having the end information is reproduced, and the silent information is reproduced until the next received voiced cell becomes reproducible.

As described above, the head / tail information is added in the payload of the cell, and the receiving side controls the sequence number check and the delay fluctuation absorption buffer based on this additional information to determine the presence / absence of voice / silence. Play.

As a result, voice cells can be transmitted using the ATM network, and the transmission efficiency can be improved.

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In the figure, a voice cell transmission apparatus according to an embodiment of the present invention includes a voice frame synchronization detection unit 1, an assembly buffer 2, a voice / non-voice detection unit 3, a status addition function unit 4, an SN (sequence number) unit 5, and a header addition. It has a transmission section including a function section 6, a header check section 8, an additional information monitoring function section 9, an SN check section 10, a reception section including a delay fluctuation absorption buffer 11 and a reassembly buffer 12.

In the transmitting section, the audio frame synchronization detecting section 1 constantly monitors the synchronization of the audio frames of the received silence compressed audio signal, and the assembly buffer 2 is used for each audio frame.
To accumulate. The assembly buffer 2 stores a voice frame, and sends one cell of data to the status addition function unit 4 in response to the sending permission from the sound / silence detection unit 3.

The sound / silence detection unit 3 determines whether or not there is sound in a voice frame for two frames, and also determines the beginning and end of speech information, and the assembly buffer 2
To the status addition function unit 4
The tail information and the head information are sent to the SN unit 5, respectively.

The status addition function unit 4 uses the data of one cell from the assembly buffer 2 to detect the sound / silence detection unit 3.
The head / tail information is added and the information is sent to the SN unit 5.
The SN unit 5 adds a sequence number to the data to which the head / tail information is added by the status addition function unit 4 to generate a payload portion of the cell.

The header addition function unit 6 attaches a header to the payload portion of the cell generated by the SN unit 5 to generate an ATM cell, and sends the ATM cell to an ATM network (not shown).

In the receiving section, the header check section 8
The corresponding cell is fetched from the TM network and the header of the received cell is checked. When the header check unit 8 determines that the received cell is addressed to itself, the header check unit 8 sends the received cell to the additional information monitoring function unit 9 and the SN check unit 10.

The additional information monitoring function unit 9 detects the additional information in the payload of the received cell, and when it detects that the additional information is the head information, it outputs a reset signal to the SN check unit 10 and the SN check unit 10 Sequence number expected value of is set to 0.

After that, the additional information monitoring function unit 9 outputs the head information to the delay fluctuation absorbing buffer 11 and sets the initial accumulation timer of the delay fluctuation absorbing buffer 11. When the additional information monitoring function unit 9 detects that the additional information of the received cell is tail information, it outputs the tail information to the delay fluctuation absorbing buffer 11 and the delay fluctuation absorbing buffer 11
Set the end cell address of.

The SN check unit 10 checks the sequence number of the received cell, performs cell interpolation when detecting cell discard, and stores the received cell in the delay fluctuation absorption buffer 11. After the initial accumulation is completed, the delay fluctuation absorption buffer 11 sets T
DM (Time Division Multipl)
e: Time division multiplex) The converted data is stored in the reassembly buffer 12 cell by cell, and the data is transmitted.

When the delay fluctuation absorption buffer 11 sends out data up to the end cell address, the reproduction of silent data is started and the initial accumulation of newly received cells is completed.
Data stored in reassembly buffer 12 (silent data)
The silent data is played back until the noise disappears.

FIG. 2 is a block diagram showing the system configuration of an embodiment of the present invention. In the figure, a voice information transmission system according to an embodiment of the present invention includes terminals 21, 29 and a PB.
X (Private Branch eXchange)
e) 22, 28 and transcoder (TRC) 23, 2
7, voice cell transmission devices 24 and 26, and an ATM network 25.

The digital voice signal sent from the terminal 21 through the PBX 22 is silence-compressed by the transcoder 23 and sent to the voice cell transmission device 24. The voice cell transmission device 24 uses only the voice information in the digital silence compression voice signal which is silence-compressed by the transcoder 23.
The cells are assembled into cells and the ATM cells are sent to the ATM network 25.

The voice cell transmission device 26 takes in an ATM cell from the ATM network 25, detects the head information and the tail information in the payload of the received cell, reproduces the voiced information and the silence information, and sends them to the transcoder 27. To do.

The transcoder 27 is a voice cell transmission device 2
The audio data received from the No. 6 is decoded, and the decoded audio data is sent to the terminal 29 through the PBX 28.
Here, since the voice cell transmission devices 24 and 26 are configured as shown in FIG. 1, the digital voice signal transmitted from the terminal 29 through the PBX 28 is also transmitted to the terminal 21 by the above-described processing operation.

FIG. 3 is a flow chart showing the processing operation of the transmitting section of the voice cell transmission apparatus shown in FIG. 1, and FIG.
6 is a flowchart showing the processing operation of the receiving section of the voice cell transmission device shown in FIG. 5, and FIG. 5 is a timing chart showing the processing operation of one embodiment of the present invention.

The operation of the embodiment of the present invention will be described with reference to FIGS. Where transcoder 2
A voice frame is assembled in the digital silence compression voice signal which is silence-compressed in 3, 27, and a bit indicating voice / non-voice is included in this voice frame (hereinafter referred to as EXT bit).
Is defined.

In the transmitting section, the audio frame synchronization detecting section 1 constantly monitors the audio frame synchronization of the digital silence compression audio signal received from the transcoders 23 and 27,
The data is stored in the assembly buffer 2 in units of audio frames.
The assembly buffer 2 stores voice frames, and
In response to the transmission permission from the silence detector 3, one cell of data is transmitted to the status addition function unit 4.

Upon receiving the EXT bit of the voice frame stored in the assembly buffer 2 (step S1 in FIG. 3), the sound / silence detecting section 3 detects a change in the EXT bit (step S2 in FIG. 3).

When the sound / silence detection unit 3 detects that the EXT bit has changed (step S3 in FIG. 3), it determines whether the EXT bit has changed to sound or silence (step S4 in FIG. 3). ).

When the sound / silence detection unit 3 determines that the EXT bit has changed to sound, it sends the head information to the status addition function unit 4 and the SN unit 5 (step S5 in FIG. 3).
The status addition function unit 4 sets the head information from the sound / silence detection unit 3 as additional information (step S in FIG. 3).
6), the SN unit 5 sets the sequence number to "0" (step S7 in FIG. 3).

At this time, the sound / silence detection unit 3 sends the sending permission to the assembly buffer 2, so that the assembly buffer 2 sends the data for one cell to the status addition function unit 4 (step S8 in FIG. 3). ).

The status addition function unit 4 uses the data for one cell from the assembly buffer 2 to detect the sound / silence detection unit 3.
Is added to the SN section 5 (step S9 in FIG. 3).

The SN section 5 attaches a sequence number to the data to which the head information is added by the status addition function section 4 (see FIG. 3).
In step S10), the payload part of the cell is generated.
The header addition function unit 6 attaches a header to the payload portion of the cell generated by the SN unit 5 to generate an ATM cell (see FIG.
In step S11), the ATM cell is sent to the ATM network 25.

When the sound / silence detection unit 3 determines that the EXT bit has changed to silence, the tail information is sent to the status addition function unit 4 and the SN unit 5 (step S in FIG. 3).
12). The status addition function unit 4 sets the tail information from the sound / silence detection unit 3 as the additional information (step S13 in FIG. 3).

At this time, the sound / silence detection unit 3 sends the sending permission to the assembly buffer 2, so that the assembly buffer 2 sends the data for one cell to the status addition function unit 4 (step S8 in FIG. 3). ).

The status addition function unit 4 uses the data for one cell from the assembly buffer 2 to detect the sound / silence detection unit 3
Is added to the end information (step S9 in FIG. 3) and sent to the SN unit 5.

The SN section 5 attaches a sequence number to the data to which the end information is added by the status addition function section 4 (see FIG. 3).
In step S10), the payload part of the cell is generated.
The header addition function unit 6 attaches a header to the payload portion of the cell generated by the SN unit 5 to generate an ATM cell (see FIG.
In step S11), the ATM cell is sent to the ATM network 25.

On the other hand, when the sound / silence detection section 3 detects that the EXT bit has not changed (step S3 in FIG. 3), the EXT
It is determined whether the bit is voiced or silent (step S14 in FIG. 3).

If the EXT bit is sound, the sound / silence detection unit 3 sends a transmission permission to the assembly buffer 2. Therefore, the assembly buffer 2 sends one cell of data to the status addition function unit 4. Yes (Fig. 3 Step S
8).

The SN section 5 attaches a sequence number to the data sent through the status addition function section 4 (step S10 in FIG. 3) and generates a payload portion of the cell. The header addition function unit 6 attaches a header to the payload portion of the cell generated by the SN unit 5 to generate an ATM cell (step S11 in FIG. 3), and sends the ATM cell to the ATM network 25.

If the EXT bit is silent, the sound / silence detection section 3 sends a disallowance to the assembly buffer 2, so that the assembly buffer 2 discards the accumulated data (step S15 in FIG. 3).

In the receiving section, the header check section 8
The corresponding cell is fetched from the TM network and the header of the received cell is checked. When the header check unit 8 determines that the received cell is addressed to itself, the header check unit 8 sends the received cell to the additional information monitoring function unit 9 and the SN check unit 10.

The additional information monitoring function unit 9 detects the additional information in the payload of the received cell (steps S21 and S2 in FIG. 4).
2) When it is detected that the additional information is the head information (step S25 in FIG. 4), the reset signal is output to the SN check unit 10 (step S26 in FIG. 4), and the expected sequence number of the SN check unit 10 is set to 0. Set to.

After that, the additional information monitoring function unit 9 outputs the head information to the delay fluctuation absorption buffer 11 and sets the initial accumulation timer of the delay fluctuation absorption buffer 11 (FIG. 4).
Step S27).

When the additional information monitoring function unit 9 detects that the additional information of the received cell is the end information (step S25 in FIG. 4), the end information is added to the delay fluctuation absorption buffer 11
To the end cell address of the delay fluctuation absorbing buffer 11 (step S29 in FIG. 4).

The SN check unit 10 checks the sequence number of the received cell (steps S23, 26, 2 in FIG. 4).
8) When cell discard is detected, cell interpolation is performed and the received cell is accumulated in the delay fluctuation absorption buffer 11 (steps S24, 27, 29 in FIG. 4). Delay fluctuation absorption buffer 11
After the initial storage is completed, the TDM-converted data is stored in the reassembly buffer 12 cell by cell and transmitted.

When the delay fluctuation absorption buffer 11 sends out data up to the end cell address, the reproduction of silent data is started, and the initial accumulation of the newly received reception cell is completed,
Data stored in reassembly buffer 12 (silent data)
The silent data is played back until the noise disappears.

In this way, at the time of transmission, the status addition function unit 4 adds the head / tail information in the payload of the cell,
The SN check unit 1 based on the head / tail information in the payload detected by the additional information monitoring function unit 9 when the cell is received.
By controlling the sequence number check by 0 and controlling the delay fluctuation absorption buffer 11, it is possible to reproduce the silent information between the voiced data.

Further, by defining the head / tail information in the payload of the cell, it becomes possible to transmit the voice cell through the ATM network 25. Therefore, it becomes possible to transmit voice cells using the ATM network 25 and minimize voice deterioration due to cell discard. In addition, the circuit scale can be suppressed to be small in order to realize silent reproduction and discard guarantee.

[0064]

As described above, according to the present invention, additional information indicating the beginning or end of a voiced portion is added to the information field, which is the storage portion of user information, and is transmitted, and the information field is received. The ATM network is used by checking the sequence number of the header part according to the additional information added to the header, playing the voiced part according to the result, and playing the silent part according to the additional information. Thus, there is an effect that a voice cell can be transmitted and the transmission efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a system configuration according to an embodiment of the present invention.

FIG. 3 is a flowchart showing a processing operation of a transmission unit of the voice cell transmission device shown in FIG.

FIG. 4 is a flowchart showing a processing operation of a receiving unit of the voice cell transmission device shown in FIG.

FIG. 5 is a timing chart showing the processing operation of the embodiment of the present invention.

[Explanation of symbols]

 1 voice frame synchronization detection unit 2 assembly buffer 3 voice / silence detection unit 4 status addition function unit 5 sequence number unit 6 header addition function unit 8 header check unit 9 additional information monitoring function unit 10 sequence number check unit 11 delay fluctuation absorption buffer 12 Reassembly buffer

Claims (7)

[Claims] 1. A transmission device for converting voice information composed of a voiced part and a silent part into a cell composed of an information field and a header part, which is a storage part of user information, and transmitting the cell, and receiving the cell to receive the cell. A voice information transmission system including a receiving device for reproducing the voiced part and the silent part from a cell, the detection means for detecting the beginning and end of the voiced part, and the detection means in the information field. The voice information transmission system, wherein the transmitter has an addition means for adding additional information indicating the beginning and the end of the detected voiced portion. 2. A voiced / non-voiced detection unit for detecting the voiced portion and the voiceless portion, and a unit for suppressing transmission of the cell when the voiced / voiceless detection unit detects the voiceless portion. The voice information transmission system according to claim 1, wherein the voice information transmission system includes the transmitter. 3. A transmission device for converting voice information consisting of a voiced part and a silent part into a cell composed of an information field which is a storage part of user information and a header part and transmitting the cell, and receiving the cell and receiving the cell. A voice information transmission system including a receiving device for reproducing the voiced part and the silent part from a cell, wherein each of the beginning and the end of the voiced part added in the information field received from the transmitting device. Additional information detection means for detecting the additional information shown, check means for checking the sequence number of the header portion according to the detection result of the additional information detection means, and the voiced portion of the sound portion according to the check result of the checking means. The voice information transmission, characterized in that the receiving device has means for reproducing and means for reproducing the silent portion according to the detection result of the additional information detecting means. Delivery system. 4. A cell to which the means for reproducing the silent portion is added with the additional information indicating the beginning of the voiced portion after the additional information detecting means detects the additional information indicating the end of the voiced portion. 4. The audio information transmission system according to claim 3, wherein the silent portion is reproduced until the reproduction of the sound is possible. 5. A transmission device for converting voice information consisting of a voiced part and a silent part into a cell composed of an information field which is a storage part of user information and a header part, and transmitting the cell, and receiving the cell and receiving the cell. A voice information transmission system including a receiving device for reproducing the voiced part and the silent part from a cell, wherein the detection means detects the beginning and end of the voiced part, and the detection means in the information field. Additional information detecting means for detecting the additional information added in the information field, the transmitting device having additional means for adding additional information indicating the beginning and the end of the detected voiced portion, respectively, Checking means for checking the sequence number of the header portion according to the detection result of the additional information detecting means, and reproduction of the voiced portion according to the check result of the checking means. Voice information transmission system, comprising cormorants means, and means for reproducing the silence according to a detection result of the additional information detection means to the receiving device. 6. A sound / silence detecting means for detecting the sound portion and the silent portion, and means for suppressing transmission of the cell when the sound / silence detecting portion detects the sound portion. The voice information transmission system according to claim 5, wherein the voice information transmission system is included in a transmitter. 7. The cell for reproducing the silent portion is a cell to which additional information indicating the end of the voiced portion is detected by the additional information detection means and then additional information indicating the beginning of the voiced portion is added. 7. The voice information transmission system according to claim 5, wherein the silent portion is reproduced until the reproduction of the voice information becomes possible.