JPH02270427A - Optical submarine repeater - Google Patents
Optical submarine repeaterInfo
- Publication number
- JPH02270427A JPH02270427A JP1090732A JP9073289A JPH02270427A JP H02270427 A JPH02270427 A JP H02270427A JP 1090732 A JP1090732 A JP 1090732A JP 9073289 A JP9073289 A JP 9073289A JP H02270427 A JPH02270427 A JP H02270427A
- Authority
- JP
- Japan
- Prior art keywords
- signal
- repeater
- monitoring
- monitor
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 28
- 238000012544 monitoring process Methods 0.000 claims abstract description 55
- 230000001172 regenerating effect Effects 0.000 claims description 16
- 238000001228 spectrum Methods 0.000 abstract description 10
- 230000005540 biological transmission Effects 0.000 abstract description 8
- 239000013307 optical fiber Substances 0.000 abstract description 5
- 238000000926 separation method Methods 0.000 abstract description 4
- 238000000034 method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000284 extract Substances 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、光海底ケーブルシステムの光海底中継器（以
下、中継器という）に関し、特にインサービスの監視機
能を備えた中継器に関するものである。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an optical submarine repeater (hereinafter referred to as a repeater) for an optical submarine cable system, and particularly relates to a repeater equipped with an in-service monitoring function. be.
従来、この種の中継器としては、ＦＤＭ海底同軸ケーブ
ルシステムで用いられるものでは、監視周波数発振器を
備えたものや、割り当て周波数で利得を高くするループ
ゲイン方式のものなどがある。そして、ＰＣＭ光海底ケ
ーブルシステムで用いられるものでは、端局からのコマ
ンド信号により、符号誤り率の測定、およびフレームフ
ォーマットの置換によるレーザダイオードのバイアス電
流の測定を行うものなどがある。（例えば、Ｊｏｕｒ−
ｎａｌ ｏｆ Ｌｉｇｈｔｗａｖｅ Ｔｅｃｈｎｏｌｏ
ｇｙ、 Ｖｏｌ、 ＬＴ −２。Conventionally, as this type of repeater used in FDM submarine coaxial cable systems, there are those equipped with a monitoring frequency oscillator, and those using a loop gain method that increases the gain at the assigned frequency. Some systems used in PCM optical submarine cable systems measure code error rates and laser diode bias currents by replacing frame formats in response to command signals from terminal stations. (For example, Jour-
nal of Lightwave Technolo
gy, Vol, LT-2.
！ｔ ６ 、ＤＥＣ，１９８４）
〔発明が解決しようとする課題〕
しかし上述した従来のＰＣＭ光海底ケーブルシステムで
用いられる中継器では、コマンド信号を端局から中継器
に送る必要があり、コマンド信号は伝送信号と同速度で
多重化されるため、伝送信号に悪影響を及ぼす場合があ
る。また、中継器ではランダムに伝送される伝送信号か
らコマンド信号を正確に抽出しなければならないため、
高度な技術が必要となり、複雑で大規模な監視回路を設
けなければならず、不経済である。さらに、端局でも同
様に監視制御装置が大規模となって不経済であり、しか
も装置のコントロールに熟練のオペレータが必要である
。! t 6, DEC, 1984) [Problems to be Solved by the Invention] However, in the repeaters used in the conventional PCM optical submarine cable system described above, it is necessary to send command signals from the terminal station to the repeater; Since it is multiplexed at the same speed as the transmission signal, it may have an adverse effect on the transmission signal. In addition, since repeaters must accurately extract command signals from randomly transmitted transmission signals,
This requires advanced technology and requires a complex and large-scale monitoring circuit, which is uneconomical. Furthermore, the monitoring and control equipment at the terminal stations is similarly large-scale and uneconomical, and moreover, a skilled operator is required to control the equipment.
本発明の目的は、このような欠点を除去し、中継器の監
視のために端局からコマンド信号を送出する必要がなく
、しかも簡素で小規模な監視回路を用いた中継器を提供
することにある。It is an object of the present invention to provide a repeater that eliminates such drawbacks, eliminates the need to send command signals from a terminal station for monitoring the repeater, and uses a simple and small-scale monitoring circuit. It is in.
本発明は、ＰＣＭ光海底ケーブルシステムを構成する晃
海底中継器において、
前記システムの光海底中継器を構成する再生増幅器に監
視回路を設け、この監視回路を、前記再生増幅器固有の
周波数の監視信号を発生する発振器と、
この発振器が出力する前記監視信号を前記中継器の状態
を表す信号で変調する変調器と、この変調器で変調され
た前記監視信号を光信号に変換してケーブルに送出する
光信号送出手段とにより構成したことを特徴とする。The present invention provides an optical submarine repeater constituting a PCM optical submarine cable system, in which a monitoring circuit is provided in a regenerative amplifier constituting the optical submarine repeater of the system, and the monitoring circuit is connected to a monitoring signal of a frequency specific to the regenerative amplifier. an oscillator that generates a signal, a modulator that modulates the monitoring signal output by the oscillator with a signal representing the state of the repeater, and a modulator that converts the monitoring signal modulated by the modulator into an optical signal and sends it to a cable. The invention is characterized in that it is constituted by an optical signal sending means.
次に本発明の実施例について図面を参照して説明する。 Next, embodiments of the present invention will be described with reference to the drawings.
第１図は本発明による中継器の一実施例を示すブロック
図である。この中継器３は２つの再生増幅器４を備え、
それぞれ海底ケーブル１を構成する光ファイバ２に接続
されている。FIG. 1 is a block diagram showing one embodiment of a repeater according to the present invention. This repeater 3 includes two regenerative amplifiers 4,
Each is connected to an optical fiber 2 constituting a submarine cable 1.
各再生増幅器４は、再生増幅回路の構成要素として、受
光回路（ＡＰＤ）５、等化増幅回路（ＥＱＬ）？、タイ
ミング回路（ＴＩＭ）８、識別回路（ＤＥＣ）９、発光
素子駆動回路（ＬＤＤ）１３、発光素子（ＬＤ）１４を
備え、監視回路の構成要素として、監視発振器（Ｏ２０
）１２、変調器（ＭＯ、Ｄ） 、１５．１６、周波数分
離フィルタ（Ｈ／Ｌ）６、増幅器（ＡＭＰ）１０、なら
びに結合器（ＨＹＢ）１１を備えている。Each regenerative amplifier 4 includes a light receiving circuit (APD) 5, an equalizing amplifier circuit (EQL), and an equalizing amplifier circuit (EQL) as components of the regenerative amplifier circuit. , a timing circuit (TIM) 8, an identification circuit (DEC) 9, a light emitting device drive circuit (LDD) 13, and a light emitting device (LD) 14, and a monitoring oscillator (O20) as a component of the monitoring circuit.
) 12, modulators (MO, D), 15.16, frequency separation filter (H/L) 6, amplifier (AMP) 10, and combiner (HYB) 11.
各再生増幅器４に入力される伝送信号は、端局から送出
される線路伝送速度のＰＣＭ信号に各中継器で発生する
監視信号が重畳されたものであり、監視信号は低周波単
一スペクトラムをもち、その周波数は各再生増幅器固有
のものとなっている。The transmission signal input to each regenerative amplifier 4 is a PCM signal at the line transmission speed sent out from the terminal station and the monitoring signal generated at each repeater is superimposed, and the monitoring signal has a low frequency single spectrum. However, the frequency is unique to each regenerative amplifier.
各再生°増幅器４の受光回路５は光ファイバ２から光信
号を受信し、電気信号に変換して周波数分離フィルタ６
に出力する。周波数分離フィルタ６は、受光回路５から
電気信号を受は取ると、高周波帯域のＰＣＭ信号と低周
波帯域の監視信号群とを分離し、前者は等化増幅回路７
に、後者は増幅器１０に出力する。The light receiving circuit 5 of each regenerative amplifier 4 receives the optical signal from the optical fiber 2, converts it into an electrical signal, and converts it into a frequency separation filter 6.
Output to. When the frequency separation filter 6 receives the electrical signal from the light receiving circuit 5, it separates the PCM signal in the high frequency band and the monitoring signal group in the low frequency band, and the former is separated from the equalization amplifier circuit 7.
The latter is then output to the amplifier 10.
等化増幅回路７に与えられたＰＣＭ信号は、等化増幅回
路７とこれに接続された識別回路９およびタイミング回
路８により再生増幅され、発光素子駆動回路１３に出力
される。また、増幅器１０に与えられた監視信号群は、
そこで中継区間の光フアイバ損失を補償するために増幅
され、結合器１１に出力される。The PCM signal applied to the equalization amplifier circuit 7 is regenerated and amplified by the equalization amplifier circuit 7 and the identification circuit 9 and timing circuit 8 connected thereto, and is output to the light emitting element drive circuit 13. Moreover, the monitoring signal group given to the amplifier 10 is
Thereupon, the signal is amplified to compensate for optical fiber loss in the repeater section, and is output to the coupler 11.
一方、監視発振器１２は再生増幅器固有の周波数の低周
波単一スペクトラムの監視信号を発生し、変調器１５に
出力する。変調器１５に出力された監視信号は、変調器
１５で受光回路５の動作状態を表す信号により１次変調
され、さらに変調器１６により発光素子１４の動作状態
を表す信号で２次変調される。なお、受光回路５および
発光素子１４の動作状態とはバイアス電圧、バイアス電
流、発光素子背面光電流などであり、また、１次変調と
２次変調とは、例えば振幅変調、周波数変調、位相変調
など異なった変調方式により行う。これらの変調を受け
た監視信号は結合器１１で、増幅器１０からの監視信号
群に重畳される。結合器１１の出力は発光素子駆動回路
１３で、識別回路９からの再生されたＰＣＭ信号に重畳
され、発光素子１４を駆動して次の中継区間へ光信号と
して送出される。On the other hand, the monitoring oscillator 12 generates a monitoring signal of a low frequency single spectrum having a frequency specific to the regenerative amplifier, and outputs it to the modulator 15. The monitoring signal output to the modulator 15 is firstly modulated by the modulator 15 with a signal representing the operating state of the light receiving circuit 5, and further secondarily modulated by the modulator 16 with a signal representing the operating state of the light emitting element 14. . Note that the operating states of the light receiving circuit 5 and the light emitting element 14 include bias voltage, bias current, light emitting element backside photocurrent, etc., and primary modulation and secondary modulation include, for example, amplitude modulation, frequency modulation, and phase modulation. This is done using different modulation methods such as These modulated monitoring signals are superimposed on a group of monitoring signals from the amplifier 10 in a combiner 11 . The output of the coupler 11 is superimposed on the regenerated PCM signal from the identification circuit 9 by the light emitting element drive circuit 13, drives the light emitting element 14, and is sent as an optical signal to the next relay section.
第２図はこのような中継器３が送出し、端局が受信する
信号をスペクトラムで表したもので、周波数ｆ□のスペ
クトラムは１番目の中継器より送出された監視信号を表
し、周波数ｆ、７のスペクトラムはｎ番目の中継器より
送出された監視信号をｉｔ。また、周波数ｆ０のスペク
トラムは線路伝送速度のＰＣＭ信号の基本周波数成分の
ものであリ、周波数２ｆｏおよび３ｆｏのスペクトラム
はその２次高調波および３次高調波のスペクトラムであ
る。そして、端局では複数の狭帯域フィルタを備え、°
それぞれのフィルタにより各周波数ｆ０〜ｆ ｓｎの監
視信号を抽出して各再生増幅器をインサービスで監視す
る。Figure 2 shows the spectrum of the signal sent out by such a repeater 3 and received by the terminal station.The spectrum at frequency f□ represents the monitoring signal sent out from the first repeater, and the spectrum at frequency f , 7 represents the monitoring signal sent from the n-th repeater. Further, the spectrum at frequency f0 is the fundamental frequency component of the PCM signal at the line transmission speed, and the spectra at frequencies 2fo and 3fo are the spectra of its second and third harmonics. The end station is equipped with multiple narrowband filters,
Each filter extracts a monitoring signal of each frequency f0 to fsn to monitor each regenerative amplifier in-service.
上述したように再生増幅器４の変調器１５．１６では、
受光回路５および発光素子１４の動作状態を表わす信号
によって監視信号を異なった方式で変調する。第３図お
よび第４図は、それぞれ異なる変調方式で変調された監
視信号の例を示すもので、具体的には端局で抽出された
監視信号の波形を示している。そして、第３図は、受光
回路５の動作状態を表わす信号で周波数ｆ Ｓｆｉの監
視信号を周波数変調し、発光素子１４の動作状態を表す
信号で振幅変調した場合の監視信号を示す。端局では、
この監視信号の振幅より発光素子１４の動作状態を知る
ことができ、一方、周波数より受光回路５の動作状態を
知ることができる。また、第４図は受光回路５の動作状
態を表す信号で周波数ｆ Ｉｌｌの監視信号を周波数変
調し、発光素子１４の動作状態を表す信号で位相変調し
た場合の監視信号を示す。図中、ｔｌ＋ Ｚ＋Ｌ３は
発光素子１４の動作状態により変化する監視信号の位相
反転の周期を表す。As mentioned above, in the modulators 15 and 16 of the regenerative amplifier 4,
The monitoring signal is modulated in different ways depending on the signals representing the operating states of the light receiving circuit 5 and the light emitting element 14. 3 and 4 show examples of supervisory signals modulated using different modulation methods, and specifically show the waveforms of the supervisory signals extracted at the terminal station. FIG. 3 shows a monitoring signal obtained by frequency-modulating the monitoring signal of frequency f Sfi with a signal representing the operating state of the light-receiving circuit 5 and amplitude-modulating it with a signal representing the operating state of the light-emitting element 14. At the end station,
The operating state of the light emitting element 14 can be known from the amplitude of this monitoring signal, while the operating state of the light receiving circuit 5 can be known from the frequency. Further, FIG. 4 shows a monitoring signal obtained by frequency-modulating the monitoring signal of frequency f Ill with a signal representing the operating state of the light-receiving circuit 5 and phase-modulating it with a signal representing the operating state of the light-emitting element 14 . In the figure, tl+Z+L3 represents the period of phase inversion of the monitoring signal that changes depending on the operating state of the light emitting element 14.
端局では、この監視信号の周波数より受光回路５の動作
状態を知ることができ、一方、位相の反転周期より発光
素子１４の動作状態を知ることができ°る。At the terminal station, the operating state of the light receiving circuit 5 can be known from the frequency of this monitoring signal, and on the other hand, the operating state of the light emitting element 14 can be known from the phase inversion period.
なお、受光回路５および発光素子１４の動作状態を表す
信号で変調された監視信号をＰＣＭ信号に重畳させる場
合、監視信号をアナログ信号として重畳させるので、監
視信号のレベルはＰＣＭ信号の１／１０以下の低レベル
とすることができ、ＰＣＭ信号のＳ／Ｎ比を大きくとる
ことができる。Note that when superimposing a monitoring signal modulated with a signal representing the operating state of the light receiving circuit 5 and the light emitting element 14 on a PCM signal, the monitoring signal is superimposed as an analog signal, so the level of the monitoring signal is 1/10 of the PCM signal. The S/N ratio of the PCM signal can be increased.
以上説明したように本発明はＰＣＭ光海底ケーブルシス
テムを構成する光海底中継器において、システムの光海
底中継器を構成する再生増幅器に監視回路を設け、この
監視回路を、再生増幅器固有の周波数の監視信号を発生
する発振器と、この発振器が出力する監視信号を中継器
の状態を表す信号で変調する変調器と、この変調器で変
調された監視信号を光信号に変換してケーブルに送出す
る光信号送出手段とにより構成している。As explained above, the present invention provides an optical submarine repeater that constitutes a PCM optical submarine cable system, in which a monitoring circuit is provided in the regenerative amplifier that constitutes the optical submarine repeater of the system, and this monitoring circuit is connected to a frequency specific to the regenerative amplifier. An oscillator that generates a monitoring signal, a modulator that modulates the monitoring signal output by the oscillator with a signal representing the state of the repeater, and a modulator that converts the monitoring signal modulated by this modulator into an optical signal and sends it to the cable. and an optical signal sending means.
従って本発明の光海底中継器では、従来のようにインサ
ービスの監視を行うために端局がら中継器を制御するコ
マンド信号を送出する必要がなく、コマンド信号が伝送
信号に影響を与えるといったことがない。また、コマン
ド信号を抽出する必要もないので、監視回路は簡素で小
規模となり、経済性が高まる。さらに、端局でも同様に
監視制御装置の小規模化が可能となるので経済性が向上
し、しかも装置のコントロールに熟練のオペレータを必
要としない。Therefore, with the optical submarine repeater of the present invention, there is no need for the terminal station to send out a command signal to control the repeater in order to perform in-service monitoring as in the past, and there is no need for the command signal to affect the transmitted signal. There is no. Furthermore, since there is no need to extract the command signal, the monitoring circuit is simple and small-scale, increasing economic efficiency. Furthermore, since it is possible to downsize the supervisory control device at the terminal station as well, economic efficiency is improved, and moreover, a skilled operator is not required to control the device.
また、この光海底中継器を用いることにより、中継器の
監視回路・および端局の監視制御装置が共に簡素で小規
模となり、操作も簡単なため、保守が容易となり、シス
テムの信頼性が向上する。In addition, by using this optical submarine repeater, both the repeater's monitoring circuit and the terminal station's monitoring and control equipment are simple and small-scale, and operation is simple, making maintenance easier and improving system reliability. do.
第１図は本発明による光海底中継器の一実施例を示すブ
ロック図、
第２図は監視信号および伝送信号のスペクトラムを示す
グラフ、
第３図、第４図は変調された監視信号を示す波形図であ
る。
１・・・海底ケーブル
２・・・光ファイバ
３・・・中継器
４・・・再生増幅器
５・・・受光回路
７・・・等化増幅回路
８・・・タイミング回路
９・・・識別回路
１０・・・増幅器
１１・・・結合器
１２・・・監視発振器
１３・・・発光素子駆動回路
１４・・・発光素子
１５、１６・・・変調器Fig. 1 is a block diagram showing an embodiment of an optical submarine repeater according to the present invention, Fig. 2 is a graph showing spectra of a monitoring signal and a transmission signal, and Figs. 3 and 4 show modulated monitoring signals. FIG. 1... Submarine cable 2... Optical fiber 3... Repeater 4... Regenerative amplifier 5... Light receiving circuit 7... Equalization amplifier circuit 8... Timing circuit 9... Identification circuit 10...Amplifier 11...Coupler 12...Monitoring oscillator 13...Light emitting element drive circuit 14...Light emitting elements 15, 16...Modulator
Claims (1)
中継器において、 前記システムの光海底中継器を構成する再生増幅器に監
視回路を設け、この監視回路を、 前記再生増幅器固有の周波数の監視信号を発生する発振
器と、 この発振器が出力する前記監視信号を前記中継器の状態
を表す信号で変調する変調器と、 この変調器で変調された前記監視信号を光信号に変換し
てケーブルに送出する光信号送出手段とにより構成した
ことを特徴とする光海底中継器。(1) In an optical submarine repeater constituting a PCM optical submarine cable system, a monitoring circuit is provided in a regenerative amplifier constituting the optical submarine repeater of the system, and this monitoring circuit transmits a monitoring signal of a frequency specific to the regenerative amplifier. a modulator that modulates the monitoring signal output by the oscillator with a signal representing the state of the repeater; and converting the monitoring signal modulated by the modulator into an optical signal and transmitting it to a cable. 1. An optical submarine repeater comprising an optical signal transmitting means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9073289A JPH07120984B2 (en) | 1989-04-12 | 1989-04-12 | Optical submarine repeater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9073289A JPH07120984B2 (en) | 1989-04-12 | 1989-04-12 | Optical submarine repeater |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02270427A true JPH02270427A (en) | 1990-11-05 |
| JPH07120984B2 JPH07120984B2 (en) | 1995-12-20 |
Family
ID=14006739
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9073289A Expired - Lifetime JPH07120984B2 (en) | 1989-04-12 | 1989-04-12 | Optical submarine repeater |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07120984B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5274496A (en) * | 1992-01-20 | 1993-12-28 | Fujitsu Limited | Optical amplifying repeater with monitor and control function |
| JPH07115391A (en) * | 1993-10-15 | 1995-05-02 | Nec Corp | Optical submarine cable grappling method and optical submarine cable system |
| JP2007533275A (en) * | 2004-04-14 | 2007-11-15 | フィニサー コーポレイション | Out-of-band data communication between network transceivers |
| WO2021177309A1 (en) * | 2020-03-02 | 2021-09-10 | 日本電気株式会社 | Monitor signal light output device, subsea apparatus, and optical communication system |
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| JPS59176937A (en) * | 1983-03-26 | 1984-10-06 | Nec Corp | System for supervising optical relay transmission line |
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1989
- 1989-04-12 JP JP9073289A patent/JPH07120984B2/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS507888A (en) * | 1973-05-23 | 1975-01-27 | ||
| JPS5011734A (en) * | 1973-06-04 | 1975-02-06 | ||
| JPS59176937A (en) * | 1983-03-26 | 1984-10-06 | Nec Corp | System for supervising optical relay transmission line |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5274496A (en) * | 1992-01-20 | 1993-12-28 | Fujitsu Limited | Optical amplifying repeater with monitor and control function |
| JPH07115391A (en) * | 1993-10-15 | 1995-05-02 | Nec Corp | Optical submarine cable grappling method and optical submarine cable system |
| JP2007533275A (en) * | 2004-04-14 | 2007-11-15 | フィニサー コーポレイション | Out-of-band data communication between network transceivers |
| WO2021177309A1 (en) * | 2020-03-02 | 2021-09-10 | 日本電気株式会社 | Monitor signal light output device, subsea apparatus, and optical communication system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07120984B2 (en) | 1995-12-20 |
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