JPH03258038A - Monitor system for optical fiber relay transmission line - Google Patents
Monitor system for optical fiber relay transmission lineInfo
- Publication number
- JPH03258038A JPH03258038A JP2056981A JP5698190A JPH03258038A JP H03258038 A JPH03258038 A JP H03258038A JP 2056981 A JP2056981 A JP 2056981A JP 5698190 A JP5698190 A JP 5698190A JP H03258038 A JPH03258038 A JP H03258038A
- Authority
- JP
- Japan
- Prior art keywords
- optical
- signal
- optical fiber
- circuit
- wavelength
- 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.)
- Pending
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 47
- 230000005540 biological transmission Effects 0.000 title claims abstract description 25
- 230000003287 optical effect Effects 0.000 claims abstract description 78
- 238000012544 monitoring process Methods 0.000 claims description 32
- 238000004891 communication Methods 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 9
- 238000005086 pumping Methods 0.000 claims description 9
- 230000001172 regenerating effect Effects 0.000 claims description 9
- 238000006243 chemical reaction Methods 0.000 abstract description 4
- 230000003321 amplification Effects 0.000 abstract description 2
- 238000003199 nucleic acid amplification method Methods 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 230000008929 regeneration Effects 0.000 description 2
- 238000011069 regeneration method Methods 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/29—Repeaters
- H04B10/291—Repeaters in which processing or amplification is carried out without conversion of the main signal from optical form
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
- H04B10/077—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using a supervisory or additional signal
- H04B10/0777—Monitoring line amplifier or line repeater equipment
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B2210/00—Indexing scheme relating to optical transmission systems
- H04B2210/07—Monitoring an optical transmission system using a supervisory signal
- H04B2210/078—Monitoring an optical transmission system using a supervisory signal using a separate wavelength
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
- Optical Communication System (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は光ファイバ中継伝送路の監視方式に関し、特に
ファイバと光中継器とを交互に接続して構成される光フ
ァイバ中継伝送路の障害位置の標定および伝送路の監視
を行う光ファイバ中継伝送路の監視方式に関する。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for monitoring optical fiber relay transmission lines, and in particular to a method for monitoring optical fiber relay transmission lines that is configured by alternately connecting fibers and optical repeaters. This invention relates to a monitoring method for optical fiber relay transmission lines that locates the position and monitors the transmission line.
従来、この種の光ファイバ中継伝送路ではパルス変調方
式が一般的に利用され、光信号は通信用主信号によりパ
ルス変調される。この光信号の波長をλ□とすると、こ
の光信号が伝送される同一の光ファイバに別の波長たと
えば波長λ２の光信号を多重伝送し、この波長λ２の光
信号を監視に使用する方式がある。この従来の方式の光
中継器では、波長λ２の光信号を光電変換して電気信号
に変換して処理している。Conventionally, in this type of optical fiber relay transmission line, a pulse modulation method is generally used, and an optical signal is pulse modulated by a communication main signal. Letting the wavelength of this optical signal be λ□, a method is to multiplex transmit an optical signal of another wavelength, for example, wavelength λ2, to the same optical fiber through which this optical signal is transmitted, and use this optical signal of wavelength λ2 for monitoring. be. In this conventional type optical repeater, an optical signal of wavelength λ2 is photoelectrically converted into an electrical signal for processing.
上述した従来の光ファイバ中継伝送路の監視方式におけ
る中継器では、通信用主信号と異る波長の光信号を電気
信号に変換しているため、光−電気変換回路と電気−光
変換回路が必要となり中継器の回路が複雑化するという
欠点がある。In the repeater in the conventional optical fiber relay transmission line monitoring system described above, the optical signal with a wavelength different from the main communication signal is converted into an electrical signal, so the optical-to-electrical conversion circuit and the electrical-to-optical conversion circuit are connected. This has the disadvantage of complicating the repeater circuit.
本発明の方式は、通信用主信号により変調された波長λ
１の光信号が伝送される光ファイバとｎ個の中継器とを
含む光ファイバ中継伝送路に前記波長λ１とは異なる波
長λ２の光信号を前記通信用主信号と同一または逆方向
に伝送させ前記波長λ２の信号を利用して光ファイバ中
継伝送路の監視を行う光ファイバ中継伝送路の監視方式
であって、前記中継器には、波長λ２の光信号を光ファ
イバから分波する光分波器と、この光分波器の出力に得
られる波長λ２の光信号を増幅する光ファイバ増幅器と
、この光ファイバ増幅器を励起する励起用光源と、この
励起用光源を前記ｎ個の中継器ごとの監視モニタ情報に
もとづきがつ中継器の識別可能な変調パターンで変調す
る変調出力を発生する変調回路と、前記光ファイバ増幅
器の出力を光ファイバに結合するとともに光ファイバを
介して入力する前記波長穴ｌの光信号を送出する光結合
器と、この光結合器の送出する前記波長λ。The method of the present invention is based on the wavelength λ modulated by the communication main signal.
An optical fiber having a wavelength λ2 different from the wavelength λ1 is transmitted in the same or opposite direction to the communication main signal through an optical fiber relay transmission line including an optical fiber through which one optical signal is transmitted and n repeaters. A monitoring system for an optical fiber relay transmission line that monitors the optical fiber relay transmission line using the signal of the wavelength λ2, wherein the repeater includes an optical demultiplexer that demultiplexes the optical signal of the wavelength λ2 from the optical fiber. an optical fiber amplifier for amplifying the optical signal of wavelength λ2 obtained from the output of the optical demultiplexer, a pumping light source for pumping this optical fiber amplifier, and a pumping light source for pumping the pumping light source to the n repeaters. a modulation circuit that generates a modulated output that is modulated with an identifiable modulation pattern of the repeater based on monitoring information for each repeater; An optical coupler that sends out the optical signal of the wavelength hole l, and the wavelength λ that is sent out from this optical coupler.
の光信号から前記通信用主信号を再生中継する光再生中
継器回路と、この光再生中継器回路の出力を前記光分波
器に送出する光送信回路と、前記光再生中継器回路と光
送信回路から前記光ファイバ中継伝送路に関する監視モ
ニタ情報を取得して前記変調回路に供給する監視回路と
を備え、前記光ファイバを介して前記中継器と接続させ
る監視局としての端局装置には、前記光結合・器を介し
て送出された波長λ２の前記光ファイバ増幅器の光信号
を分波する光分波器と、この光分波器の光出力信号を電
気信号に変換する光−電気変換器と、この光−電気変換
器の出力を監視する監視信号処理装置とを併設して構成
される。an optical regenerative repeater circuit that regenerates and repeats the communication main signal from the optical signal of the optical regenerative repeater circuit, an optical transmitting circuit that sends the output of the optical regenerative repeater circuit to the optical demultiplexer, and an optical regenerative repeater circuit and an optical An end station device as a monitoring station connected to the repeater via the optical fiber, comprising a monitoring circuit that acquires monitoring information regarding the optical fiber relay transmission line from a transmission circuit and supplies it to the modulation circuit. , an optical demultiplexer that demultiplexes the optical signal of the optical fiber amplifier having a wavelength λ2 transmitted through the optical coupler/device, and an optical-electrical demultiplexer that converts the optical output signal of the optical demultiplexer into an electrical signal. It is configured to include a converter and a monitoring signal processing device that monitors the output of this optical-to-electrical converter.
次に、本発明について図面を参照して説明する。 Next, the present invention will be explained with reference to the drawings.
第１図は本発明の一実施例のブロック図である。FIG. 1 is a block diagram of one embodiment of the present invention.
第１図は本発明による中継器の一実施例であり、２は光
ファイバ、１１は光結合器、１２は光再生中継回路、１
３は光送信回路、１４は光分波器。FIG. 1 shows an embodiment of a repeater according to the present invention, in which 2 is an optical fiber, 11 is an optical coupler, 12 is an optical regenerative repeater circuit, 1
3 is an optical transmission circuit, and 14 is an optical demultiplexer.
１５は監視回路、１６は光ファイバ増幅器、１７は光フ
ァイバ増幅器の励起用光源、１８は励起用光源を変調す
る変調回路である。15 is a monitoring circuit, 16 is an optical fiber amplifier, 17 is a pumping light source for the optical fiber amplifier, and 18 is a modulation circuit for modulating the pumping light source.
波長λ１の光信号は通信用主信号により変調されている
。一般に、光ファイバ中継伝送路ではパルス符号変調（
ＰＣＭ）方式が採用され、波形等化（Ｒｅｓｈａｐｉｎ
ｇ）、識別再生（Ｒｅｇｅｎｅｒａｔｉｎｇ ）および
タイミング再生（Ｒｅｔｉｍｉｎｇ）のいわゆる３Ｒ機
能による３Ｒ中継伝送することによって符号誤り率、ジ
ッタ特性等の劣化を抑圧している。このような中継器を
用いた障害点の探索や中継器の監視に波長多重した波長
λ２の光信号を用いる本発明は方式構成図を第２図に示
す。The optical signal of wavelength λ1 is modulated by the communication main signal. Generally, optical fiber relay transmission lines use pulse code modulation (
PCM) method is adopted, and waveform equalization (Reshapin
g) Deterioration in code error rate, jitter characteristics, etc. is suppressed by performing 3R relay transmission using so-called 3R functions of identification regeneration (Regenerating) and timing regeneration (Retiming). FIG. 2 shows a system configuration diagram of the present invention, which uses wavelength-multiplexed optical signals of wavelength λ2 to search for failure points and monitor repeaters using such repeaters.
中継器の監視を行う場合、例えば光送信回路のレーザダ
イオードのバイアス電流値あるいは受光レベル、符号誤
り（ＢＥＲ）のモニタ特性を光再生中継器回路１２と光
送信回路１３がら監視回路１５にとりこみ処理し、処理
信号を変調回路８に送る。変調回路１８は、中継器の識
別可能な変調パターン、たとえば中継器ごとに異る固有
の周波数の低周波信号でこの監視回路１５の出力信号を
変調するようにして変調出力を発生し、この変調出力で
励起用光源１７の出力光を変調する。これにより光ファ
イバ増幅器１７の増幅度が変化し波長λ２の監視信号に
挿入される。When monitoring a repeater, for example, the bias current value of the laser diode of the optical transmitter circuit, the light reception level, and the monitor characteristics of the code error (BER) are imported into the monitoring circuit 15 from the optical regenerative repeater circuit 12 and the optical transmitter circuit 13 and processed. and sends the processed signal to the modulation circuit 8. The modulation circuit 18 generates a modulated output by modulating the output signal of the monitoring circuit 15 with an identifiable modulation pattern of the repeater, for example, a low frequency signal with a unique frequency that differs from repeater to repeater. The output light of the excitation light source 17 is modulated by the output. This changes the amplification degree of the optical fiber amplifier 17 and is inserted into the monitoring signal of wavelength λ2.
一方、中継器１の出力する波長λ２の監視信号を受ける
監視局たる端局装置３は、波長λ２の光ファイバ増幅器
１６の光結合器１１による光信号を分波する光分波器と
、この光分波器の光出力信号を電気信号に変換する光−
電気変換器とを備えて変換した電気信号の監視信号を出
力し、端局装置３に併設した監視信号処理装置４で監視
し、中継器ごとに固有の周波数の低周波信号を利用する
監視信号の周波数を光分波器で取り出し、各中継器ごと
の動作状態を知る。On the other hand, the terminal equipment 3, which is a monitoring station that receives the monitoring signal of the wavelength λ2 outputted from the repeater 1, includes an optical demultiplexer that demultiplexes the optical signal from the optical coupler 11 of the optical fiber amplifier 16 of the wavelength λ2; Light that converts the optical output signal of an optical demultiplexer into an electrical signal -
A monitoring signal that outputs a monitoring signal of the converted electrical signal by an electrical converter, is monitored by a monitoring signal processing device 4 attached to the terminal device 3, and uses a low frequency signal with a frequency unique to each repeater. The frequency is extracted using an optical demultiplexer and the operating status of each repeater is determined.
以上説明したように本発明は、波長多重伝送した主信号
と異る波長を監視信号に使用し、中継器の監視回路を光
電変換を行うことなく光ファイバ増幅器を使用すること
により、中継器回路構成が著しく簡単になるという効果
がある。As explained above, the present invention uses a wavelength different from the wavelength-multiplexed main signal for the monitoring signal, and uses an optical fiber amplifier for the repeater monitoring circuit without performing photoelectric conversion. This has the effect of significantly simplifying the configuration.
第１図は本発明による光ファイバ中継伝送路の監視方式
における中継器の一実施例のブロック図、第２図は本発
明による光ファイバ中継伝送路のシステム構成を示すブ
ロック図である。
１・・・中継器、２・・・光ファイバ、３・・・端局装
置、４・・・監視信号処理装置、１１・・・光結合器、
１２・・・光再生中継器回路、１３・・・光送信回路、
１４・・・光分波器、１５・・・監視回路、１６・・・
光ファイバ、１７・・・励起用光源、１８・・・変調回
路。FIG. 1 is a block diagram of an embodiment of a repeater in the optical fiber relay transmission line monitoring system according to the present invention, and FIG. 2 is a block diagram showing the system configuration of the optical fiber relay transmission line according to the present invention. DESCRIPTION OF SYMBOLS 1... Repeater, 2... Optical fiber, 3... Terminal device, 4... Supervisory signal processing device, 11... Optical coupler,
12... Optical regenerative repeater circuit, 13... Optical transmission circuit,
14... Optical demultiplexer, 15... Monitoring circuit, 16...
Optical fiber, 17... excitation light source, 18... modulation circuit.
Claims (1)
送される光ファイバとｎ個の中継器とを含む光ファイバ
中継伝送路に前記波長λ＿１とは異なる波長λ＿２の光
信号を前記通信用主信号と同一または逆方向に伝送させ
前記波長λ＿２の信号を利用して光ファイバ中継伝送路
の監視を行う光ファイバ中継伝送路の監視方式であつて
、前記中継器には、波長λ＿２の光信号を光ファイバか
ら分波する光分波器と、この光分波器の出力に得られる
波長λ＿２の光信号を増幅する光ファイバ増幅器と、こ
の光ファイバ増幅器を励起する励起用光源と、この励起
用光源を前記ｎ個の中継器ごとの監視モニタ情報にもと
づきかつ中継器の識別可能な変調パターンで変調する変
調出力を発生する変調回路と、前記光ファイバ増幅器の
出力を光ファイバに結合するとともに光ファイバを介し
て入力する前記波長λ＿１の光信号を送出する光結合器
と、この光結合器の送出する前記波長λ＿１の光信号か
ら前記通信用主信号を再生中継する光再生中継器回路と
、この光再生中継器回路の出力を前記光分波器に送出す
る光送信回路と、前記光再生中継器回路と光送信回路か
ら前記光ファイバ中継伝送路に関する監視モニタ情報を
取得して前記変調回路に供給する監視回路とを備え、前
記光ファイバを介して前記中継器と接続させる監視局と
しての端局装置には、前記光結合器を介して送出された
波長λ＿２の前記光ファイバ増幅器の光信号を分波する
光分波器と、この光分波器の光出力信号を電気信号に変
換する光−電気変換器と、この光−電気変換器の出力を
監視する監視信号処理装置とを併設して成ることを特徴
とする光ファイバ中継伝送路の監視方式。An optical signal with a wavelength λ_2 different from the wavelength λ_1 is transmitted to the communication main signal on an optical fiber relay transmission line including an optical fiber and n repeaters, through which an optical signal with a wavelength λ_1 modulated by the communication main signal is transmitted. A monitoring method for an optical fiber relay transmission line in which the optical fiber relay transmission line is monitored by using a signal of the wavelength λ_2 transmitted in the same direction as the signal or in the opposite direction to that of the signal, wherein the optical fiber relay transmission line is monitored by using the signal of the wavelength λ_2. an optical demultiplexer that demultiplexes the optical signal from an optical fiber, an optical fiber amplifier that amplifies the optical signal of wavelength λ_2 obtained from the output of the optical demultiplexer, a pumping light source that pumps the optical fiber amplifier, and a pumping light source that pumps the optical fiber amplifier. a modulation circuit that generates a modulated output that modulates the optical light source based on the monitoring information for each of the n repeaters and with a modulation pattern that can be identified by the repeaters; and a modulation circuit that couples the output of the optical fiber amplifier to an optical fiber. an optical coupler that sends out an optical signal with the wavelength λ_1 that is input via an optical fiber; and an optical regenerative repeater circuit that regenerates and repeats the communication main signal from the optical signal with the wavelength λ_1 sent out from the optical coupler. , an optical transmitter circuit that sends the output of the optical regenerator circuit to the optical demultiplexer; and an optical transmitter circuit that transmits the output of the optical regenerator circuit to the optical demultiplexer, and obtains monitoring information regarding the optical fiber relay transmission line from the optical regenerator circuit and the optical transmitter circuit to perform the modulation. The end station device as a monitoring station is equipped with a monitoring circuit for supplying the circuit and is connected to the repeater via the optical fiber. An optical demultiplexer that demultiplexes an optical signal, an optical-to-electrical converter that converts the optical output signal of the optical demultiplexer into an electrical signal, and a monitoring signal processing device that monitors the output of the optical-to-electrical converter. A monitoring method for an optical fiber relay transmission line, characterized in that it is also equipped with a.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2056981A JPH03258038A (en) | 1990-03-07 | 1990-03-07 | Monitor system for optical fiber relay transmission line |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2056981A JPH03258038A (en) | 1990-03-07 | 1990-03-07 | Monitor system for optical fiber relay transmission line |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03258038A true JPH03258038A (en) | 1991-11-18 |
Family
ID=13042682
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2056981A Pending JPH03258038A (en) | 1990-03-07 | 1990-03-07 | Monitor system for optical fiber relay transmission line |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03258038A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06326667A (en) * | 1993-05-14 | 1994-11-25 | Nec Corp | Method and system for transferring alarm by multi-stage repeating |
| US5440418A (en) * | 1992-07-15 | 1995-08-08 | Oki Electric Industry Co., Ltd. | Method and apparatus for alarm surveillance for an optical transmission system |
| US5510925A (en) * | 1993-09-20 | 1996-04-23 | Fujitsu Limited | Relay transmission system including optical amplification |
| US5926304A (en) * | 1996-03-15 | 1999-07-20 | Nec Corporation | Optical fiber amp repeater of amplifying an optical signal and superimposing an auxiliary signal |
| US6266169B1 (en) | 1992-04-08 | 2001-07-24 | Hitachi, Ltd. | Optical transmission equipment which transmits an amplified optical data signal and an optical surveillance signal |
-
1990
- 1990-03-07 JP JP2056981A patent/JPH03258038A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6266169B1 (en) | 1992-04-08 | 2001-07-24 | Hitachi, Ltd. | Optical transmission equipment which transmits an amplified optical data signal and an optical surveillance signal |
| US6728489B2 (en) | 1992-04-08 | 2004-04-27 | Hitachi, Ltd. | Optical transmission system constructing method and system |
| US7167652B2 (en) | 1992-04-08 | 2007-01-23 | Hitachi, Ltd | Optical transmission system constructing method and system |
| US7292785B2 (en) | 1992-04-08 | 2007-11-06 | Hitachi, Ltd. | Optical transmission system constructing method and system |
| US5440418A (en) * | 1992-07-15 | 1995-08-08 | Oki Electric Industry Co., Ltd. | Method and apparatus for alarm surveillance for an optical transmission system |
| JPH06326667A (en) * | 1993-05-14 | 1994-11-25 | Nec Corp | Method and system for transferring alarm by multi-stage repeating |
| US5510925A (en) * | 1993-09-20 | 1996-04-23 | Fujitsu Limited | Relay transmission system including optical amplification |
| US5926304A (en) * | 1996-03-15 | 1999-07-20 | Nec Corporation | Optical fiber amp repeater of amplifying an optical signal and superimposing an auxiliary signal |
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