JPH08214342A - In-band signal communication system - Google Patents
In-band signal communication systemInfo
- Publication number
- JPH08214342A JPH08214342A JP1915195A JP1915195A JPH08214342A JP H08214342 A JPH08214342 A JP H08214342A JP 1915195 A JP1915195 A JP 1915195A JP 1915195 A JP1915195 A JP 1915195A JP H08214342 A JPH08214342 A JP H08214342A
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- tone
- band signal
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、専用線側から交換機側
へ通信を行うにあたり、帯域内信号方式によって電話交
換を行う場合、帯域内信号装置において呼び出し音およ
び話中音中継時に専用線からのノイズを減衰または無く
すようにする帯域内信号通信システムに関するものであ
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to communication from a leased line side to an exchange side, and when telephone exchange is performed by an in-band signaling system, the in-band signaling device is used to relay a ringing tone and a busy tone from the leased line. The present invention relates to an in-band signal communication system for attenuating or eliminating the noise of the above.
【０００２】なお、帯域内信号方式とは電話交換方式の
発信、選択信号送受、切断等の信号を音声帯域内の監視
信号で行うシステムである。The in-band signaling system is a system for transmitting signals of the telephone exchange system, transmitting / receiving selection signals, disconnecting signals, etc. by using supervisory signals in the voice band.
【０００３】[0003]
【従来の技術】従来のこのような分野の帯域内信号装置
は、呼び出し音および話中音中継時では、通話路へノッ
チフィルタを挿入し、監視信号の通過阻止のみを行って
いるものであった。2. Description of the Related Art A conventional in-band signal device in such a field is to insert a notch filter into a speech path and only prevent passage of a supervisory signal at the time of relaying a ringing tone and a busy tone. It was
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、上記し
た従来の帯域内信号装置におけるノイズ減衰方法では、
中継局交換機内でデジタル−アナログ変換により発生し
た量子化ノイズは、通過してしまうという問題点があっ
た。本発明は、上記問題点を除去し、帯域内信号装置に
おいて呼び出し音および話中音中継時に専用線からのノ
イズを減衰させるまたは無くする帯域内信号通信システ
ムを提供することを目的とする。However, in the above-described conventional noise attenuation method in the in-band signal apparatus,
There is a problem that the quantization noise generated by the digital-analog conversion in the relay station exchange passes through. SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the above problems and provide an in-band signal communication system that attenuates or eliminates noise from a leased line in relaying a ringing tone and a busy tone in an in-band signal device.
【０００５】[0005]
【課題を解決するための手段】本発明は、上記目的を達
成するために、 （１）専用線側から交換機側へ通信を行うにあたり、帯
域内信号方式によって電話交換を行う帯域内信号通信シ
ステムにおいて、呼び出し音または話中音中継時に通話
路へ挿入されるノイズ減衰回路（５）を設け、専用線
（Ｌ）からのノイズを減衰するようにしたものである。In order to achieve the above object, the present invention provides: (1) In-band signal communication system in which telephone exchange is performed by an in-band signal system in communication from the leased line side to the exchange side. In the above, a noise attenuating circuit (5) which is inserted into the communication path at the time of relaying a ringing tone or a busy tone is provided so as to attenuate noise from the leased line (L).
【０００６】（２）専用線側から交換機側へ通信を行う
にあたり、帯域内信号方式によって電話交換を行う帯域
内信号通信システムにおいて、呼び出し音・話中音検出
回路（１７）と呼び出し音・話中音発信回路（１５）を
設け、前記呼び出し音・話中音検出回路（１７）の検出
信号に基づいて、呼び出し音または話中音中継時のみ通
話路を切り離し、前記呼び出し音・話中音発信回路（１
５）を交換機側へ接続するようにしたものである。(2) A ringing tone / busy tone detecting circuit (17) and a ringing tone / talk in an in-band signal communication system in which a telephone exchange is performed by an in-band signaling system in performing communication from the leased line side to the exchange side. A middle tone transmitting circuit (15) is provided, and based on the detection signal of the ringing tone / busy tone detecting circuit (17), the call path is disconnected only when the ringing tone or the busy tone is relayed, and the ringing tone / busy tone is generated. Transmission circuit (1
5) is connected to the exchange side.
【０００７】[0007]
（Ａ）上記（１）記載の帯域内信号通信システムによれ
ば、専用線からの呼び出し音または話中音中継時、通話
路へノイズ減衰回路が挿入され、専用線からのノイズを
減衰することができる。実験結果ではホワイトノイズを
２０ｄＢ以上減衰することができた。(A) According to the in-band signal communication system described in (1), a noise attenuating circuit is inserted in the communication path at the time of relaying a ringing tone or a busy tone from a leased line to attenuate noise from the leased line. You can According to the experimental result, the white noise could be attenuated by 20 dB or more.
【０００８】また、ノイズ減衰回路は能動素子および汎
用演算増幅器のみで実現できるため、安価である。 （Ｂ）上記（２）記載の帯域内信号通信システムによれ
ば、専用線側からの呼び出し音または話中音中継時のみ
通話路が切り離され、呼び出し音・話中音発信回路が交
換機側へ接続されることにより、ノイズを完全に通過さ
せないようにすることができる。Further, the noise attenuating circuit can be realized only by the active element and the general-purpose operational amplifier, so that it is inexpensive. (B) According to the in-band signal communication system described in (2) above, the call path is disconnected only when the ringing tone or busy tone is relayed from the leased line side, and the ringing tone / busy tone transmitting circuit is sent to the exchange side. By being connected, noise can be prevented from passing completely.
【０００９】[0009]
【実施例】本発明の実施例について図を参照しながら説
明する。図１は本発明の第１実施例を示す帯域内信号通
信システムを示すブロック図である。専用線Ｌは、第１
の整合トランス１を介して、第１の増幅器２の入力へ接
続される。第１の増幅器２の出力は、第１のスイッチ３
の端子ａ、監視信号の通過阻止を行うためのノッチフィ
ルタ４及び帯域内信号検出回路６へ接続される。ノッチ
フィルタ４の出力は、ノイズ減衰回路５の入力及び第２
のスイッチ７の端子ｂへ接続される。ノイズ減衰回路５
の出力は、第２のスイッチ７の端子ａへ接続される。第
２のスイッチ７の端子ｃは第１のスイッチ３の端子ｂへ
接続され、また、第１のスイッチ３の端子ｃは第２の増
幅器８の入力へ接続される。Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an in-band signal communication system showing a first embodiment of the present invention. The dedicated line L is the first
Is connected to the input of the first amplifier 2 via the matching transformer 1. The output of the first amplifier 2 is the output of the first switch 3
Is connected to the terminal a, the notch filter 4 for blocking the passage of the monitor signal, and the in-band signal detection circuit 6. The output of the notch filter 4 is the input of the noise attenuating circuit 5 and the second
Is connected to the terminal b of the switch 7. Noise attenuation circuit 5
Is connected to the terminal a of the second switch 7. The terminal c of the second switch 7 is connected to the terminal b of the first switch 3, and the terminal c of the first switch 3 is connected to the input of the second amplifier 8.
【００１０】第２の増幅器８の出力は、第２の整合トラ
ンス９を介し構内交換機へ接続されている。また、構内
交換機からの地気信号Ｓａは地気信号検出回路１０へ接
続されている。なお、第１のスイッチ３は帯域内信号検
出回路６の検出結果および地気信号検出回路１０の検出
結果により制御され、第２のスイッチ７は地気信号検出
回路１０の検出結果により制御される。なお、図１にお
いて、ＳV1は音声及び帯域内信号、ＳV2は音声信号であ
る。The output of the second amplifier 8 is connected to a private branch exchange via a second matching transformer 9. Further, the ground signal Sa from the private branch exchange is connected to the ground signal detection circuit 10. The first switch 3 is controlled by the detection result of the in-band signal detection circuit 6 and the detection result of the ground signal detection circuit 10, and the second switch 7 is controlled by the detection result of the ground signal detection circuit 10. . In FIG. 1, S V1 is a voice and in-band signal, and S V2 is a voice signal.
【００１１】図２は図１に示されるノイズ減衰回路の回
路図であり、図２の（ａ）部は正帰還形２次ローパスフ
ィルタでカットオフ周波数３７１（Ｈｚ），Ｑ＝０．６
５７２５であり、図２の（ｂ）部は正帰還形２次ローパ
スフィルタでカットオフ周波数５９３（Ｈｚ），Ｑ＝
２．５３６１１であり、図２の（ａ）、（ｂ）部合わせ
てチェビシェフ特性４次ローパスフィルタ、カットオフ
周波数５５０（Ｈｚ）のフィルタを形成している。各図
２（ａ）、（ｂ）部のフィルタ構成、特性は一般的なも
のである。なお、Ｒ1 〜Ｒ8 は抵抗、Ｃ1 〜Ｃ4 はコン
デンサ、Ｓ1 はノイズ減衰回路への入力信号、Ｓ2 はノ
イズ減衰回路からの出力信号である。FIG. 2 is a circuit diagram of the noise attenuating circuit shown in FIG. 1. Part (a) of FIG. 2 is a positive feedback type second-order low-pass filter with a cutoff frequency of 371 (Hz) and Q = 0.6.
5725, the part (b) of FIG. 2 is a positive feedback second-order low-pass filter with a cutoff frequency of 593 (Hz), Q =
2.53611, and a Chebyshev characteristic fourth-order low-pass filter and a filter with a cutoff frequency of 550 (Hz) are formed by combining parts (a) and (b) of FIG. The filter configuration and characteristics of each of FIGS. 2A and 2B are general. Note that R 1 to R 8 are resistors, C 1 to C 4 are capacitors, S 1 is an input signal to the noise attenuating circuit, and S 2 is an output signal from the noise attenuating circuit.
【００１２】まず、平常状態では第１のスイッチ３は端
子ｂへ接続され、第２のスイッチ７は端子ｂへ接続され
ている。交換機側より発信信号（地気信号）Ｓａを受信
すると、第１のスイッチ３は状態を維持し、第２のスイ
ッチ７は端子ａへ接続され、通話路へノイズ減衰回路５
が挿入される。この時、相手側（専用線側）の状態によ
り呼び出し音または話中音が中継されている。次に、専
用線側より応答信号（帯域内信号の断）を帯域内信号検
出回路６により受信すると、第１のスイッチ３は端子ａ
へ接続され、第２のスイッチ７は状態を維持する。First, in a normal state, the first switch 3 is connected to the terminal b, and the second switch 7 is connected to the terminal b. When the transmission signal (ground signal) Sa is received from the exchange side, the first switch 3 maintains the state, the second switch 7 is connected to the terminal a, and the noise attenuating circuit 5 is connected to the communication path.
Is inserted. At this time, a ringing tone or a busy tone is relayed depending on the state of the other party (dedicated line side). Next, when a response signal (disconnection of the in-band signal) is received by the in-band signal detection circuit 6 from the dedicated line side, the first switch 3 causes the terminal a
And the second switch 7 maintains the state.
【００１３】そこで、交換機側よりの切断信号（オープ
ン状態）を受信すると、第１のスイッチ３は端子ｂへ接
続され、第２のスイッチ７は端子ｂへ接続される。ま
た、専用線より終話信号（帯域内信号）を受信すると、
第１のスイッチ３は端子ｂへ接続され、第２のスイッチ
７は状態を維持し、交換機側からの切断信号により第２
のスイッチ７は端子ｂへ接続される。Therefore, when the disconnection signal (open state) from the exchange side is received, the first switch 3 is connected to the terminal b and the second switch 7 is connected to the terminal b. Also, when receiving the end signal (in-band signal) from the leased line,
The first switch 3 is connected to the terminal b, the second switch 7 maintains the state, and the second signal is given by the disconnection signal from the exchange side.
Switch 7 is connected to terminal b.
【００１４】図３は本発明の第２実施例を示す帯域内信
号装置を示すブロック図である。専用線Ｌは、第１の整
合トランス１１を介し第１の増幅器１２へ接続される。
第１の増幅器１２の出力は、第１のスイッチ１３の端子
ａ、ノッチフィルタ１４、帯域内信号検出回路１６及び
呼び出し音・話中音検出回路１７へ接続される。ノッチ
フィルタ１４の出力は、第２のスイッチ１８の端子ａへ
接続され、呼び出し音・話中音発信回路１５の出力は第
２のスイッチ１８の端子ｂへ接続される。FIG. 3 is a block diagram showing an in-band signal apparatus showing a second embodiment of the present invention. The dedicated line L is connected to the first amplifier 12 via the first matching transformer 11.
The output of the first amplifier 12 is connected to the terminal a of the first switch 13, the notch filter 14, the in-band signal detection circuit 16 and the ringing tone / busy tone detection circuit 17. The output of the notch filter 14 is connected to the terminal a of the second switch 18, and the output of the ringing tone / busy sound transmitting circuit 15 is connected to the terminal b of the second switch 18.
【００１５】第２のスイッチ１８の端子ｃは、第１のス
イッチ１３の端子ｂへ接続される。第１のスイッチ１３
の端子ｃは、第２の増幅器１９の入力へ接続される。第
２の増幅器１９の出力は、第２の整合トランス２０を介
し構内交換機へ接続されている。また、構内交換機から
の地気信号Ｓａは地気信号検出回路２１へ接続されてい
る。The terminal c of the second switch 18 is connected to the terminal b of the first switch 13. First switch 13
Terminal c of is connected to the input of the second amplifier 19. The output of the second amplifier 19 is connected to the private branch exchange via the second matching transformer 20. Further, the ground signal Sa from the private branch exchange is connected to the ground signal detection circuit 21.
【００１６】なお、第１のスイッチ１３は帯域内信号検
出回路１６の検出結果および地気信号検出回路２１の検
出結果により制御され、第２のスイッチ１８は呼び出し
音・話中音検出回路１７の検出結果により制御されてい
る。呼び出し音・話中音検出回路１７および呼び出し音
・話中音発信回路１５は汎用ＩＣを用いてマイコンにて
監視・制御する。The first switch 13 is controlled by the detection result of the in-band signal detection circuit 16 and the detection result of the ground signal detection circuit 21, and the second switch 18 of the ring tone / busy sound detection circuit 17 is controlled. It is controlled by the detection result. The ringing tone / busy tone detecting circuit 17 and the ringing tone / busy tone transmitting circuit 15 are monitored / controlled by a microcomputer using a general-purpose IC.
【００１７】まず、平常状態では第１のスイッチ１３は
端子ｂへ接続され、第２のスイッチ１８は端子ａへ接続
されている。交換機側より発信信号（地気信号）を受信
すると、第１のスイッチ１３は状態を維持する。この
時、専用線側線呼び出し音又は話中音を受信し、呼び出
し音・話中音検出回路１７により検出された時のみ、第
２のスイッチ１８は端子ｂへ接続される。すなわち、通
話路は切り離され、呼び出し音又は話中音のみが送出さ
れる。First, in a normal state, the first switch 13 is connected to the terminal b and the second switch 18 is connected to the terminal a. When receiving the transmission signal (ground signal) from the exchange side, the first switch 13 maintains the state. At this time, the second switch 18 is connected to the terminal b only when the ringing tone or busy tone of the leased line is received and detected by the ringing tone / busy tone detecting circuit 17. That is, the communication path is separated and only the ringing tone or the busy tone is transmitted.
【００１８】次に、専用線側より応答信号（帯域内信号
の断）を受信すると、第１のスイッチ１３は端子ａ側へ
接続される。この時、専用線側の呼び出し音は断となっ
ているので、第２のスイッチ１８は端子ａへ接続されて
いる。交換機側よりの切断信号（オープン状態）を受信
すると、第１のスイッチ１３は端子ｂへ接続される。ま
た、専用線より終話信号（帯域内信号）を受信すると第
１のスイッチ１３は端子ｂへ接続される。なお、図３に
おいて、ＳV1は音声及び帯域内信号、ＳV2は音声信号で
ある。Next, when a response signal (disconnection of the in-band signal) is received from the dedicated line side, the first switch 13 is connected to the terminal a side. At this time, the ringing tone on the dedicated line side is cut off, so the second switch 18 is connected to the terminal a. When the disconnection signal (open state) is received from the exchange side, the first switch 13 is connected to the terminal b. Further, when the call end signal (in-band signal) is received from the dedicated line, the first switch 13 is connected to the terminal b. In FIG. 3, S V1 is a voice and in-band signal, and S V2 is a voice signal.
【００１９】第１実施例では、ノイズ減衰回路としてロ
ーパスフィルタを用いて説明したが、バンドパスフィル
タを用いることもできる。なお、本発明は上記実施例に
限定されるものではなく、本発明の趣旨に基づいて種々
の変形が可能であり、これらを本発明の範囲から排除す
るものではない。In the first embodiment, the low-pass filter is used as the noise attenuating circuit, but a band-pass filter can also be used. The present invention is not limited to the above-mentioned embodiments, and various modifications can be made based on the spirit of the present invention, and these modifications are not excluded from the scope of the present invention.
【００２０】[0020]
【発明の効果】以上、詳細に説明したように、本発明に
よれば、 （１）請求項１記載の発明によれば、専用線からの呼び
出し音または話中音中継時、通話路へノイズ減衰回路が
挿入され、専用線からのノイズを減衰することができ
る。実験結果ではホワイトノイズを２０ｄＢ以上減衰す
ることができた。As described above in detail, according to the present invention, (1) According to the invention described in claim 1, when the ringing tone or the busy tone is relayed from the leased line, noise is added to the communication path. An attenuator circuit is inserted to attenuate the noise from the leased line. According to the experimental result, the white noise could be attenuated by 20 dB or more.
【００２１】また、ノイズ減衰回路は能動素子および汎
用演算増幅器のみで実現できるため、安価である。 （２）請求項２記載の発明によれば、専用線側からの呼
び出し音または話中音中継時のみ通話路が切り離され、
呼び出し音・話中音発信回路が交換機側へ接続されるこ
とにより、ノイズを完全に通過させないようにすること
ができる。Further, the noise attenuating circuit can be realized only by the active element and the general-purpose operational amplifier, so that it is inexpensive. (2) According to the invention of claim 2, the call path is disconnected only when the ringing tone or busy tone is relayed from the leased line side,
By connecting the ringing tone / busy tone transmitting circuit to the exchange side, it is possible to completely prevent the passage of noise.
【図１】本発明の第１実施例を示す帯域内信号通信シテ
スムを示すブロック図である。FIG. 1 is a block diagram showing an in-band signal communication system showing a first embodiment of the present invention.
【図２】図１に示されるノイズ減衰回路の回路図であ
る。FIG. 2 is a circuit diagram of the noise attenuation circuit shown in FIG.
【図３】本発明の第２実施例を示す帯域内信号通信シテ
スムを示すブロック図である。FIG. 3 is a block diagram showing an in-band signal communication system showing a second embodiment of the present invention.
１，１１ 第１の整合トランス ２，１２ 第１の増幅器 ３，１３ 第１のスイッチ ４，１４ ノッチフィルタ ５ ノイズ減衰回路 ６，１６ 帯域内信号検出回路 ７，１８ 第２のスイッチ ８，１９ 第２の増幅器 ９，２０ 第２の整合トランス １０，２１ 地気信号検出回路 １５ 呼び出し音・話中音発信回路 １７ 呼び出し音・話中音検出回路 1, 11 1st matching transformer 2, 12 1st amplifier 3, 13 1st switch 4, 14 Notch filter 5 Noise attenuation circuit 6, 16 In-band signal detection circuit 7, 18 2nd switch 8, 19th 2 amplifier 9,20 2nd matching transformer 10,21 Geoelectric signal detection circuit 15 Ringing tone / busy tone transmitting circuit 17 Ringing tone / busy tone detecting circuit
Claims (2)
たり、帯域内信号方式によって電話交換を行う帯域内信
号通信システムにおいて、 呼び出し音または話中音中継時に通話路へ挿入されるノ
イズ減衰回路を設け、専用線からのノイズを減衰させる
ようにしたことを特徴とする帯域内信号通信システム。1. A noise attenuating circuit to be inserted into a communication path when a ringing tone or a busy tone is relayed in an in-band signal communication system in which a telephone exchange is performed by an in-band signal system when communication is performed from a leased line side to an exchange side. Is provided to attenuate the noise from the dedicated line, and the in-band signal communication system is characterized.
たり、帯域内信号方式によって電話交換を行う帯域内信
号通信システムにおいて、 呼び出し音・話中音検出回路と呼び出し音・話中音発信
回路を設け、前記呼び出し音・話中音検出回路の検出信
号に基づいて、呼び出し音または話中音中継時のみ通話
路を切り離し、前記呼び出し音・話中音発信回路を交換
機側へ接続するようにしたことを特徴とする帯域内信号
通信システム。2. A ringing tone / busy tone detection circuit and a ringing tone / busy tone transmitting circuit in an in-band signal communication system in which telephone exchange is performed by an in-band signal system when performing communication from the leased line side to the exchange side. Based on the detection signal of the ringing tone / busy tone detecting circuit, the call path is disconnected only when the ringing tone or busy tone is relayed, and the ringing tone / busy tone transmitting circuit is connected to the exchange side. An in-band signal communication system characterized by the above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01915195A JP3247268B2 (en) | 1995-02-07 | 1995-02-07 | In-band signal communication system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01915195A JP3247268B2 (en) | 1995-02-07 | 1995-02-07 | In-band signal communication system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08214342A true JPH08214342A (en) | 1996-08-20 |
| JP3247268B2 JP3247268B2 (en) | 2002-01-15 |
Family
ID=11991437
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01915195A Expired - Fee Related JP3247268B2 (en) | 1995-02-07 | 1995-02-07 | In-band signal communication system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3247268B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100464146B1 (en) * | 2000-06-23 | 2004-12-31 | 엘지전자 주식회사 | Apparatus for data selecting in switching system |
-
1995
- 1995-02-07 JP JP01915195A patent/JP3247268B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100464146B1 (en) * | 2000-06-23 | 2004-12-31 | 엘지전자 주식회사 | Apparatus for data selecting in switching system |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3247268B2 (en) | 2002-01-15 |
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