JPH09307522A - High efficiency voice coder - Google Patents
High efficiency voice coderInfo
- Publication number
- JPH09307522A JPH09307522A JP12014496A JP12014496A JPH09307522A JP H09307522 A JPH09307522 A JP H09307522A JP 12014496 A JP12014496 A JP 12014496A JP 12014496 A JP12014496 A JP 12014496A JP H09307522 A JPH09307522 A JP H09307522A
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- efficiency
- speed
- pcm
- Prior art date
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は高速ディジタル専用
回線を使用し、音声帯域の信号伝送を高能率音声符号化
により行う通信網において、中継交換機に接続された高
能率音声符号化装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-efficiency voice coding apparatus connected to a repeater exchange in a communication network which uses a high-speed digital leased line and performs voice band signal transmission by high-efficiency voice coding.
【０００２】[0002]
【従来の技術】一般に、高能率音声符号化はＧ．７２８
（１６ＫＬＤ−ＣＥＬＰ）などに代表される音声符号化
方式であり、μ−ｌｏｗＰＣＭ（６４ｋｂｐｓ）音声符
号化に比べ１／４に圧縮でき、ＴＤＭなどと組合わせる
ことにより、専用回線のコストを低減できるため採用さ
れている。2. Description of the Related Art Generally, high-efficiency speech coding is based on G.264. 728
(16KLD-CELP), which is a voice coding method, can compress to 1/4 compared to μ-low PCM (64 kbps) voice coding, and can reduce the cost of a dedicated line by combining with TDM and the like. Has been adopted for.
【０００３】従来、高速ディジタル専用回線を使用し、
音声帯域の信号伝送を高能率音声符号化により行う通信
網において中継交換を行う場合、中継交換機がＰＢ信号
（ＤＴＭＦ）の局間信号の中継状態に移行したことを高
能率音声符号化装置が検出することによって、高能率音
声符号化装置が符号化・復号化を行わない中継状態へと
切替われるようになっている。Conventionally, a high-speed digital leased line has been used,
When relay switching is performed in a communication network that performs voice band signal transmission by high-efficiency voice encoding, the high-efficiency voice encoding device detects that the relay exchange has transitioned to a relay state of inter-station signal of PB signal (DTMF). By doing so, the high-efficiency speech coding apparatus is switched to the relay state in which coding / decoding is not performed.
【０００４】図１，図３及び図４を参照して詳細に説明
する。This will be described in detail with reference to FIGS. 1, 3 and 4.
【０００５】図１は高能率音声符号化を採用する通信網
の一例を示す。この通信網は電話機１，１１を収容して
回線交換を行なう交換機ＬＳ２，１０と、中継交換を行
なう中継交換機ＴＬＳ７と、符号化音声と他のデータ等
を多重化し高速ディジタル専用回線にのせる多重化装置
ＭＵＸ４，５，８と、高能率音声符号化・復号化を行な
う高能率音声符号化装置ＣＯＤＥＣ３，６，９とから構
成されている。ここで、ＣＯＤＥＣ６は入力の高能率符
号化音声信号をＰＣＭ音声信号に復号する復号化器と、
高能率符号化音声信号（１６ｋｂｐｓ）を通常のＰＣＭ
音声信号の伝送速度である６４ｋｂｐｓに速度変換する
速度変換回路と、ＴＬＳ７からのＰＣＭ音声信号を符号
化する符号化器と、速度変換された符号化データを復元
する速度変換回路と、ＴＬＳ７にむけてパススルー識別
信号（Ｘ．５０フレーム等）を７５０μＳ毎にビットス
チールによりＬＳＢに挿入する（図４参照）識別信号挿
入回路と、挿入された識別信号により中継状態を検出す
る中継状態検出回路とを含んでいる（詳細ブロックは図
示省略）。なお、中継呼の発生しないＬＳ２，１０対応
のＣＯＤＥＣ３，９はＣＯＤＥＣ６と異なり、符号化器
ＣＯＤ及び復号化器ＤＥＣだけの単純な構成で良い。FIG. 1 shows an example of a communication network that employs high efficiency speech coding. In this communication network, exchanges LS2 and 10 for accommodating telephones 1 and 11 for performing line exchange, a relay exchange TLS7 for performing relay exchange, coded voice and other data are multiplexed and placed on a high-speed digital leased line. The MUXs 4, 5 and 8 and the high-efficiency speech coding devices CODECs 3, 6 and 9 for performing high-efficiency speech coding / decoding. Here, the CODEC 6 is a decoder for decoding the input high-efficiency coded audio signal into a PCM audio signal,
High-efficiency coded audio signal (16 kbps) is converted to normal PCM
A speed conversion circuit for speed conversion to 64 kbps which is a transmission speed of an audio signal, an encoder for encoding the PCM audio signal from the TLS7, a speed conversion circuit for restoring the speed-converted encoded data, and a TLS7. A pass-through identification signal (X.50 frame or the like) is inserted into the LSB by bit stealing every 750 μS (see FIG. 4), and a relay state detection circuit for detecting the relay state by the inserted identification signal. Included (detailed block not shown). Unlike the CODEC 6, the CODECs 3 and 9 corresponding to the LSs 2 and 10 in which the relay call does not occur may have a simple configuration including only the encoder COD and the decoder DEC.
【０００６】この構成において、中継交換機の接続方式
が全蓄積一括送出以外の場合における電話機１から電話
機１１にむけて発信したときのＣＯＤＥＣ６のパススル
ー中継交換シーケンスを図３に示す。ＴＬＳ７はＬＳ２
からのＰＢ信号形式の選択信号（局間信号）を全て受け
ずに次の方路を決定できるため、ＬＳ１０向けの選択信
号を送出する前に中継動作に入る。このため図３のＤＥ
Ｔ点でＣＯＤＥＣ６の中継状態検出回路が働きパススル
ー状態となり、ＬＳ１０向けの選択信号が途切れてしま
う。FIG. 3 shows the pass-through relay exchange sequence of the CODEC 6 when a call is made from the telephone 1 to the telephone 11 in the case where the connection system of the relay exchange is other than the all-storage batch transmission in this configuration. TLS7 is LS2
Since the next route can be determined without receiving all the selection signals (inter-station signals) in the PB signal format from (1), the relay operation is started before the selection signal for the LS10 is transmitted. Therefore, the DE of FIG.
At the point T, the relay state detection circuit of the CODEC 6 operates to enter the pass-through state, and the selection signal for the LS10 is interrupted.
【０００７】[0007]
【発明が解決しようとする課題】上述したように、局間
信号にＰＢ信号を用いる場合、中継交換機によってはＰ
Ｂ信号伝送中に中継状態へ移行してしまう場合があり、
高能率音声符号化装置が中継交換機に同期して中継状態
へ移行してしまうことによって、正常なＰＢ信号が伝送
できなくなり、中継交換及び通信が確立しないという問
題がある。As described above, when the PB signal is used as the inter-station signal, the P
There is a case that it transits to the relay state during B signal transmission,
Since the high-efficiency voice encoding device shifts to the relay state in synchronization with the relay exchange, there is a problem that a normal PB signal cannot be transmitted and relay exchange and communication are not established.
【０００８】[0008]
【課題を解決するための手段】本発明の高能率音声符号
化装置は、中継交換機側からのＰＣＭ信号を高能率符号
化信号に符号化する符号化手段と、前記ＰＣＭ信号を高
能率符号化信号の伝送速度に変換する第１の速度変換手
段と、前記符号化手段及び前記第１の速度変換手段の出
力を選択し高速ディジタル専用回線側へ出力する第１の
選択手段と、前記専用回線側からの高能率符号化信号を
ＰＣＭ信号に復号化する復号化手段と、前記専用回線側
からの高能率符号化信号をＰＣＭ信号の伝送速度に変換
する第２の速度変換手段と、前記復号化手段及び前記第
２の速度変換手段の出力を選択し前記中継交換機側へ出
力する第２の選択手段と、前記中継交換機に出力するＰ
ＣＭ信号にこの中継交換機の中継状態を識別するための
識別信号を挿入する識別信号挿入手段と、ＰＣＭ信号に
挿入された識別信号を検出したときは前記第１及び第２
の選択手段をそれぞれ前記第１及び第２の速度変換手段
の出力選択側に切替えさせる中継状態検出手段と、前記
中継交換機側のＰＢ信号を監視しこのＰＢ信号を検出し
ている期間中は前記中継状態検出手段による識別信号の
検出と前記識別信号挿入手段による識別信号の挿入動作
を停止させるＰＢ検出手段とを備える。A high-efficiency speech coding apparatus according to the present invention comprises a coding means for coding a PCM signal from a repeater exchange side into a high-efficiency coded signal, and a high-efficiency coding for the PCM signal. First speed converting means for converting to a signal transmission speed, first selecting means for selecting the output of the encoding means and the first speed converting means and outputting to the high speed digital leased line side, and the leased line Decoding means for decoding a high-efficiency coded signal from the side into a PCM signal, second speed converting means for converting the high-efficiency coded signal from the dedicated line side into a transmission rate of the PCM signal, and the decoding Second selecting means for selecting the output of the converting means and the second speed converting means and outputting it to the transit exchange side, and P for outputting to the transit exchange.
Identification signal inserting means for inserting an identification signal for identifying the relay state of the repeater exchange in the CM signal, and the first and second when the identification signal inserted in the PCM signal is detected.
Relay state detecting means for switching the selecting means to the output selecting side of the first and second speed converting means, respectively, and the PB signal on the side of the repeater exchange is monitored and the PB signal is detected during the period. The relay state detecting means includes the detection of the identification signal and the PB detection means for stopping the operation of inserting the identification signal by the identification signal inserting means.
【０００９】この構成において、前記高速ディジタル専
用回線上の前記高能率符号化信号の伝送速度が１６ｋｂ
ｐｓであり、また前記識別信号は前記識別信号挿入手段
において前記ＰＣＭ信号に周期的にビットスチールによ
り挿入される。In this structure, the transmission rate of the high efficiency coded signal on the high speed digital leased line is 16 kb.
ps, and the identification signal is periodically inserted by bit steal into the PCM signal in the identification signal inserting means.
【００１０】[0010]
【発明の実施の形態】次に、本発明の実施の一形態につ
いて図面を参照しながら説明する。BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to the drawings.
【００１１】図２は本発明の高能率音声符号化装置の実
施の一形態を示し、図１に示す通信網のＣＯＤＥＣ６を
改良した詳細構成である。高能率音声符号化装置は高速
ディジタル専用回線に接続された多重化装置ＭＵＸ５を
介して入力される高能率符号化音声信号（１６ｋｂｐ
ｓ）をＰＣＭ音声信号（６４ｋｂｐｓ）に復号する復号
化器ＤＥＣ１３と、符号化音声信号を通常のＰＣＭ音声
信号の伝送速度である６４ｋｂｐｓに速度変換する速度
変換回路ＣＯＮＶ１２と、中継交換機ＴＬＳ７からのＰ
ＣＭ音声信号を符号化する符号化器ＣＯＤ１７と、速度
変換された符号化データを復元する速度変換回路ＣＯＮ
Ｖ１８と、ＴＬＳ７にむけてパススルー識別信号を挿入
する識別信号挿入回路ＧＥＮ１５と、挿入された識別信
号により中継状態を検出する中継状態検出回路ＤＥＴ１
９と、ＴＬＳ７からのＰＢ信号（ＤＴＭＦ）を検出しＤ
ＥＴ１９がＴＬＳ７の中継状態を検出した場合でもＰＢ
信号が検出されている間は選択回路ＳＥＬ１４，１６に
速度変換回路側へ切替えることを禁止するとともにＧＥ
Ｎ１５がＰＣＭ音声信号に識別信号を挿入することを禁
止するＰＢ検出回路ＰＢ２０とを備える。FIG. 2 shows an embodiment of the high-efficiency speech coding apparatus of the present invention, which is a detailed configuration in which the CODEC 6 of the communication network shown in FIG. 1 is improved. The high-efficiency speech coding apparatus is a high-efficiency coding speech signal (16 kbp) input via a multiplexer MUX5 connected to a high-speed digital leased line.
s) into a PCM voice signal (64 kbps), a decoder DEC13, a speed conversion circuit CONV12 for converting the coded voice signal into 64 kbps which is a normal PCM voice signal transmission speed, and a P from the repeater exchange TLS7.
Encoder COD17 for encoding CM voice signal and speed conversion circuit CON for restoring speed-converted encoded data
V18, an identification signal insertion circuit GEN15 for inserting a pass-through identification signal toward the TLS7, and a relay state detection circuit DET1 for detecting the relay state by the inserted identification signal.
9 and the PB signal (DTMF) from TLS7 is detected and D
Even if ET19 detects the relay status of TLS7, PB
While the signal is being detected, the selection circuits SEL14, 16 are prohibited from switching to the speed conversion circuit side and the GE
And a PB detection circuit PB20 for prohibiting N15 from inserting the identification signal into the PCM audio signal.
【００１２】上述した構成の高能率音声符号化装置ＣＯ
ＤＥＣ６を図１に示す通信網に適用した構成において、
電話機１から電話機１１に発信する場合について説明す
る。選択信号によりＬＳ２が行き先を決定し、ＣＯＤＥ
Ｃ３から高速ディジタル専用回線及びＭＵＸ４，５を介
してＣＯＤＥＣ６に接続される。ＣＯＤＥＣ６のＤＥＣ
１３側ではＧＥＮ１５によって識別信号の挿入されたＰ
ＣＭ音声信号を常にＴＬＳ７に向けて出力している。Ｐ
Ｂ信号形式の局間信号である選択信号を受けてＴＬＳ７
が中継交換状態になると、ＣＯＤＥＣ６のＣＯＤ１７側
のＤＥＴ１９が識別信号を検出する。これは図３のＤＥ
Ｔ点に相当するが、ＰＢ２０がＧＥＮ１５を動作禁止に
するとともに、ＤＥＴ１９がＳＥＬ１４，１６の切替動
作を禁止する。そのため選択信号であるＰＢ信号は途切
れることなく次局のＬＳ１０に伝送される。ＰＢ２０は
ＰＢ信号が検出されなくなると、それまで禁止していた
ＰＣＭ音声信号への識別信号の挿入と検出を再開させる
ので、ＤＥＴ１９がＳＥＬ１４をＣＯＮＶ１２に切替え
させ（図３のＳＥＬ時点）パススルー中継交換状態とな
る。A high-efficiency speech coder CO having the above-mentioned structure
In the configuration in which the DEC6 is applied to the communication network shown in FIG. 1,
A case of making a call from the telephone 1 to the telephone 11 will be described. The selection signal causes LS2 to determine the destination, and CODE
It is connected to CODEC 6 from C3 through the high-speed digital leased line and MUXs 4 and 5. DEC of CODEC6
On the 13 side, P with the identification signal inserted by GEN15
The CM audio signal is always output to TLS7. P
In response to a selection signal which is an inter-station signal of B signal format, TLS7
Becomes a relay exchange state, the DET 19 on the COD 17 side of the CODEC 6 detects the identification signal. This is the DE of Figure 3
Although it corresponds to the point T, the PB 20 prohibits the operation of the GEN 15 and the DET 19 prohibits the switching operation of the SELs 14 and 16. Therefore, the PB signal that is the selection signal is transmitted to the LS 10 of the next station without interruption. When the PB signal is no longer detected, the PB 20 restarts the insertion and detection of the identification signal into the PCM voice signal, which has been prohibited until then, so that the DET 19 switches the SEL 14 to the CONV 12 (at the time of SEL in FIG. 3) pass-through relay exchange. It becomes a state.
【００１３】[0013]
【発明の効果】以上説明したように本発明は、中継交換
機に接続される高能率音声符号化装置において、局間信
号にＰＢ（ＤＴＭＦ）信号を用いる中継交換の場合、Ｐ
Ｂ信号伝送中に中継交換機が中継状態へ移行しても、Ｐ
Ｂ検出手段を有することにより高能率音声符号化装置が
中継状態へ移行しないため、ＰＢ信号を正しく伝送で
き、中継交換及び通信を確立させることができる。As described above, according to the present invention, in the high efficiency voice coding apparatus connected to the repeater exchange, in the case of the repeater exchange using the PB (DTMF) signal as the inter-station signal, the P
Even if the transit exchange shifts to the transit state during B signal transmission, P
Since the high-efficiency speech coding apparatus does not shift to the relay state by having the B detecting means, the PB signal can be correctly transmitted, and relay switching and communication can be established.
【図１】本発明及び従来技術に関わる通信網の一例を示
す。FIG. 1 shows an example of a communication network according to the present invention and the related art.
【図２】本発明の実施の一形態を示すブロック図。FIG. 2 is a block diagram showing one embodiment of the present invention.
【図３】パススルー中継交換シーケンスを説明するため
の図。FIG. 3 is a diagram for explaining a pass-through relay exchange sequence.
【図４】速度交換フォーマットを示す図。FIG. 4 is a diagram showing a speed exchange format.
６ 高能率音声符号化装置（ＣＯＤＥＣ） ７ 中継交換機（ＴＬＳ） １２ 速度変換回路（ＣＯＮＶ） １３ 復号化器（ＤＥＣ） １４ 選択回路（ＳＥＬ） １５ 識別信号挿入回路（ＧＥＮ） １６ 選択回路（ＳＥＬ） １７ 符号化器（ＣＯＤ） １８ 速度変換回路（ＣＯＮＶ） １９ 中継状態検出回路（ＤＥＴ） ２０ ＰＢ検出回路（ＰＢ） 6 High-efficiency speech encoder (CODEC) 7 Repeater switch (TLS) 12 Speed conversion circuit (CONV) 13 Decoder (DEC) 14 Selection circuit (SEL) 15 Identification signal insertion circuit (GEN) 16 Selection circuit (SEL) 17 Encoder (COD) 18 Speed Conversion Circuit (CONV) 19 Relay State Detection Circuit (DET) 20 PB Detection Circuit (PB)
Claims (3)
符号化信号に符号化する符号化手段と、前記ＰＣＭ信号
を高能率符号化信号の伝送速度に変換する第１の速度変
換手段と、前記符号化手段及び前記第１の速度変換手段
の出力を選択し高速ディジタル専用回線側へ出力する第
１の選択手段と、前記専用回線側からの高能率符号化信
号をＰＣＭ信号に復号化する復号化手段と、前記専用回
線側からの高能率符号化信号をＰＣＭ信号の伝送速度に
変換する第２の速度変換手段と、前記復号化手段及び前
記第２の速度変換手段の出力を選択し前記中継交換機側
へ出力する第２の選択手段と、前記中継交換機に出力す
るＰＣＭ信号にこの中継交換機の中継状態を識別するた
めの識別信号を挿入する識別信号挿入手段と、ＰＣＭ信
号に挿入された識別信号を検出したときは前記第１及び
第２の選択手段をそれぞれ前記第１及び第２の速度変換
手段の出力選択側に切替えさせる中継状態検出手段と、
前記中継交換機側のＰＢ信号を監視しこのＰＢ信号を検
出している期間中は前記中継状態検出手段による識別信
号の検出と前記識別信号挿入手段による識別信号の挿入
動作を停止させるＰＢ検出手段とを備えることを特徴と
する高能率音声符号化装置。1. A coding means for coding a PCM signal from the repeater exchange side into a high-efficiency coded signal, and a first speed conversion means for converting the PCM signal into a transmission rate of the high-efficiency coded signal, First selection means for selecting the output of the encoding means and the first speed conversion means and outputting it to the high-speed digital leased line side, and for decoding the high-efficiency coded signal from the leased line side into a PCM signal Decoding means, second speed converting means for converting a high-efficiency coded signal from the dedicated line side into a transmission speed of a PCM signal, and selecting outputs of the decoding means and the second speed converting means. Second selecting means for outputting to the repeater exchange side; identification signal inserting means for inserting an identifying signal for identifying the relay state of the repeater exchange into the PCM signal for outputting to the repeater exchange; Identification Relay state detecting means for switching the first and second selecting means to the output selecting side of the first and second speed converting means, respectively, when a signal is detected,
PB detecting means for monitoring the PB signal on the side of the repeater exchange and stopping the operation of detecting the identification signal by the relay state detecting means and the operation of inserting the identification signal by the identification signal inserting means during the period of detecting the PB signal. A high-efficiency speech coding apparatus comprising:
能率符号化信号の伝送速度が１６ｋｂｐｓであることを
特徴とする請求項１記載の高能率音声符号化装置。2. The high-efficiency speech encoding apparatus according to claim 1, wherein the transmission rate of the high-efficiency encoded signal on the high-speed digital leased line is 16 kbps.
おいて前記ＰＣＭ信号に周期的にビットスチールにより
挿入されることを特徴とする請求項１記載の高能率音声
符号化装置。3. The high-efficiency speech coding apparatus according to claim 1, wherein said identification signal is periodically inserted into said PCM signal by bit steal in said identification signal inserting means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12014496A JP2878183B2 (en) | 1996-05-15 | 1996-05-15 | Highly efficient speech coder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12014496A JP2878183B2 (en) | 1996-05-15 | 1996-05-15 | Highly efficient speech coder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09307522A true JPH09307522A (en) | 1997-11-28 |
| JP2878183B2 JP2878183B2 (en) | 1999-04-05 |
Family
ID=14779062
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12014496A Expired - Fee Related JP2878183B2 (en) | 1996-05-15 | 1996-05-15 | Highly efficient speech coder |
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| Country | Link |
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| JP (1) | JP2878183B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100469270B1 (en) * | 2002-07-29 | 2005-02-02 | 엘지전자 주식회사 | Device and Method for processing speech signal in communication system |
-
1996
- 1996-05-15 JP JP12014496A patent/JP2878183B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100469270B1 (en) * | 2002-07-29 | 2005-02-02 | 엘지전자 주식회사 | Device and Method for processing speech signal in communication system |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2878183B2 (en) | 1999-04-05 |
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