JPS63160436A - Maintenance method for optical signal line - Google Patents
Maintenance method for optical signal lineInfo
- Publication number
- JPS63160436A JPS63160436A JP61313611A JP31361186A JPS63160436A JP S63160436 A JPS63160436 A JP S63160436A JP 61313611 A JP61313611 A JP 61313611A JP 31361186 A JP31361186 A JP 31361186A JP S63160436 A JPS63160436 A JP S63160436A
- Authority
- JP
- Japan
- Prior art keywords
- optical signal
- wavelength
- optical
- line
- communication
- 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
- 230000003287 optical effect Effects 0.000 title claims abstract description 89
- 238000012423 maintenance Methods 0.000 title claims abstract description 13
- 238000000034 method Methods 0.000 title claims description 20
- 238000004891 communication Methods 0.000 claims abstract description 49
- 238000007689 inspection Methods 0.000 claims description 11
- 238000000253 optical time-domain reflectometry Methods 0.000 claims description 7
- 239000000835 fiber Substances 0.000 claims description 5
- 238000012544 monitoring process Methods 0.000 claims description 5
- 230000005540 biological transmission Effects 0.000 claims description 4
- 230000001902 propagating effect Effects 0.000 claims description 2
- 239000013307 optical fiber Substances 0.000 abstract description 11
- 238000012360 testing method Methods 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 5
- 238000005452 bending Methods 0.000 description 3
- 210000004899 c-terminal region Anatomy 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Optical Communication System (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は光信号線路の保守方法に関する。より詳細には
、光ファイバ等の光信号線路を、該信号線路における光
通信を途絶することなく検査することのできる新規な光
信号線路の保守方法に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for maintaining optical signal lines. More specifically, the present invention relates to a novel method for maintaining an optical signal line, such as an optical fiber, which can be inspected without interrupting optical communications on the signal line.
従来の技術
近年、石英系光ファイバを伝送路として用いた通信シス
テムの実用化が図られ、我が国の公衆通信回線において
も、中継系通信回線には大容量システム（Ｆ−４００Ｍ
）並びに中小容量システム（Ｆ−３２ＭＳＦ−１００Ｍ
）が既に実用化されており、４００Ｍｂｓ大容量通信シ
ステムが実用化されている。また、来るべき通信サービ
スの多様化に対応するために、将来は加入者系への光通
信システムの導入も検討されている。Background of the Invention In recent years, communication systems using quartz-based optical fibers as transmission lines have been put into practical use, and even in Japan's public communication lines, high-capacity systems (F-400M) are used for relay communication lines.
) and small and medium capacity systems (F-32MSF-100M
) has already been put into practical use, and a 400 Mbs large capacity communication system has been put into practical use. Furthermore, in order to respond to the coming diversification of communication services, the introduction of optical communication systems to subscriber systems is being considered in the future.
ところで、同軸ケーブル廊の銅ケーブルに代わって光ケ
ーブルを使用するとなると、光信号線路の保守技術の確
立が重要な課題となる。即ち、光信号線路の保守にあた
っては、局内加入者端末間で現用回線から予備回線への
切替えを行うような回線切替え技術や現用回線が使用中
であるかどうかあるいは切替えるようとする回線が正し
く対象の回線であるかどうかを判断する回線モニタ技術
などが不可避なものとなる。By the way, when optical cables are used in place of copper cables in coaxial cable corridors, establishing maintenance techniques for optical signal lines becomes an important issue. In other words, when maintaining optical signal lines, the target is line switching technology such as switching from a working line to a protection line between subscriber terminals in an office, whether the working line is in use, or whether the line to be switched is correctly targeted. Line monitoring technology that determines whether a line is connected or not is inevitable.
このような保守作業における通信回線のモニタあるいは
切替えは、光フアイバケーブルの何れかの端部のコネク
タを取りはずし、受光器あるいは予備回線に接続するこ
とによって行っている。Monitoring or switching of communication lines during such maintenance work is performed by removing the connector at either end of the optical fiber cable and connecting it to a light receiver or a backup line.
発明が解決しようとする問題点
しかしながら、このような回線のモニタ時ならびに切替
え時には、その回線は中断されることになり、通常の回
線使用状態においてこれらを行うことはできなかった。Problems to be Solved by the Invention However, when monitoring and switching such a line, the line would be interrupted, and these operations could not be carried out under normal line usage conditions.
例えば、信号線路の障害点を検索する技術としてＯＴ
Ｄ Ｒ（Ｏｐｔｉｃａｌ Ｔｉｍｅ Ｄｏｍａｉｎ Ｒ
ｅｆｌｅｃｔｏｍｅｔｅｒ）法が広く知られている。即
ち、ＯＴＤＲ法は従来の同軸ケーブルにおける障害点検
知方法であるパルス試験器を光通信に応用したものであ
り、光ファイバにパルス幅の狭い光パルス信号を入射し
、ファイバの光軸方向の各点における散乱光から入射端
方向へ反射伝搬される光信号を入射側の端部で受光し、
これを時間軸上にプロットすることによってファイバの
障害点の位置を標定するものである。このような障害点
検知のために信号線路にパルス信号を送出する必要があ
るので、実際には通信回線の一端を取り外して試験器に
接続する必要がある。また、このときその回線の通信を
中断せざるを得ないことはいうまでもない。For example, OT is used as a technology to search for failure points in signal lines.
DR (Optical Time Domain R)
The eflectometer method is widely known. In other words, the OTDR method is an application of a pulse tester, which is a conventional method for detecting fault points in coaxial cables, to optical communications.It injects an optical pulse signal with a narrow pulse width into an optical fiber, and detects each point in the optical axis direction of the fiber. The optical signal reflected and propagated from the scattered light at the point toward the input end is received at the input end,
By plotting this on the time axis, the position of the fiber failure point can be located. Since it is necessary to send a pulse signal to the signal line in order to detect such a fault point, it is actually necessary to remove one end of the communication line and connect it to the tester. Moreover, it goes without saying that at this time, communication on that line must be interrupted.
しかしながら、保守あるいは修復作業のためにその回線
に関わる通信が途絶することは、特に加入者系の通信回
線においては絶対に避けなければならなず、この点を克
服しない限り光通信回線を実用的に加入者系に適用する
ことはできない。However, interruption of communication related to the line due to maintenance or repair work must be avoided at all costs, especially in subscriber-based communication lines, and unless this point is overcome, optical communication lines will not be practical. cannot be applied to subscriber systems.
そこで、本発明は上記従来技術の問題点を解決し、通信
回線の機能を中断することなく当該回線のモニタあるい
は切替えを行う技術を実現することを目的としている。SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve the problems of the prior art described above and to realize a technique for monitoring or switching a communication line without interrupting the function of the communication line.
問題点を解決するための手段
即ち、本発明に従い、所定の第１波長の光信号を伝送す
る光信号線路に、該光信号の波長とは異なる第２波長の
光信号を注入並びに抽出する手段を挿入し、前記第１波
長の光信号による通信を途絶することなく、前記第２波
長の光信号を用いて光伝送路の状態を検査することを特
徴とする光信号線路の保守方法が提供される。Means for solving the problem, that is, according to the present invention, a means for injecting and extracting an optical signal of a second wavelength different from the wavelength of the optical signal into an optical signal line that transmits an optical signal of a predetermined first wavelength. Provided is a maintenance method for an optical signal line, characterized in that the condition of the optical transmission line is inspected using the optical signal of the second wavelength without interrupting the communication using the optical signal of the first wavelength. be done.
作用
本発明に従う光信号線路の保守方法は、その光信号線路
が通信のために使用している信号光の波長とは異なる波
長の光信号に対して有効な分波および合波機能を有する
手段を、この光信号線路に゛予め挿入しておき、保守点
検の際に、この通信用信号光とは異なる波長の信号光を
利用することをその主要な特徴としている。Operation The method for maintaining an optical signal line according to the present invention is a means for the optical signal line to have effective demultiplexing and multiplexing functions for optical signals having a wavelength different from the wavelength of the signal light used for communication. is inserted into this optical signal line in advance, and the main feature is that a signal light having a wavelength different from this communication signal light is used during maintenance and inspection.
即ち、所定の波長の信号光を伝播している光信号線路に
対して、この通信用の信号光とは異なる波長の検査用信
号光を注入しても、この光信号線路上の通信信号光は影
響を受けない。従って、通常の通信を中断することなく
光信号線路の保守点検を行う事が出来る。In other words, even if test signal light of a wavelength different from the communication signal light is injected into an optical signal line that propagates signal light of a predetermined wavelength, the communication signal light on this optical signal line is not affected. Therefore, maintenance and inspection of the optical signal line can be performed without interrupting normal communication.
尚、検査用光の注入並びに抽出手段としては、信号線路
に挿入された通信用信号光を透過するような分波フィル
ターあるいは通信用信号線路に方向性結合によって接続
された光ファイバ等の公知の技術を広く適用することが
できる。In addition, as a means for injecting and extracting the inspection light, a known method such as a branching filter that transmits the communication signal light inserted into the signal line or an optical fiber connected to the communication signal line by directional coupling can be used. The technology can be widely applied.
実施例
以下に図面を参照して本発明についてより具体的に詳述
するが、以下に開示するものは本発明の一実施例に過ぎ
ず、本発明の技術的範囲を何等限定するものではない。EXAMPLES The present invention will be described in more detail below with reference to the drawings, but what is disclosed below is only one example of the present invention and does not limit the technical scope of the present invention in any way. .
第１図は、本発明に従う光信号線路の保守方法において
光信号の注入あるいは抽出のために好適に用いることが
できる、光学部材の構成を概略的に示すものである。FIG. 1 schematically shows the configuration of an optical member that can be suitably used for injecting or extracting optical signals in the optical signal line maintenance method according to the present invention.
即ち、第１図において、光ケーブルｌａＳ ｌｂは光通
信回線における光信号線路であり、光信号は、この光ケ
ーブルに収容された光フアイバ心線２ａ、２ｂを伝播す
る。That is, in FIG. 1, an optical cable laS lb is an optical signal line in an optical communication line, and an optical signal propagates through optical fiber cores 2a and 2b accommodated in this optical cable.
光フアイバ心線２ａ、２ｂの互いに対向する端部にはプ
ラグ３ａ、３ｂがそれぞれ固定されており、このプラグ
３ａ、３ｂを介して分波器並びに合波器として機能する
光学部材４が結合されてい； る・
この光学部材４は、例えば、この通信回線の信号光波長
λ１の光を全透過し、他のある波長λ２を全反射するよ
うな分波フィルターを用いればよい。この場合、第１図
に表示したＡ−８間、即ち通信回線としての信号線路は
常に確保されている。Plugs 3a and 3b are fixed to mutually opposing ends of the optical fibers 2a and 2b, respectively, and an optical member 4 functioning as a demultiplexer and a multiplexer is coupled via the plugs 3a and 3b. As the optical member 4, for example, a branching filter may be used that completely transmits the signal light wavelength λ1 of the communication line and totally reflects the other wavelength λ2. In this case, the signal line between A and 8 shown in FIG. 1, ie, the communication line, is always secured.
一方、プラグＣあるいはＤに何らかの機器を接続した場
合、信号線路に対して波長λ２の光信号を注入あるいは
抽出することができる。On the other hand, when some device is connected to the plug C or D, an optical signal of wavelength λ2 can be injected into or extracted from the signal line.
○ＴＤＲ測定を行う場合は、プラグ１１を有するピグテ
ール１２を介して波長λ２の光信号によって測定を行う
ＯＴＤＲ測定器１３を、光学部材４のＣ端子に接続する
ことにより、光フアイバ心線２ｂに対する検査を実施す
ることができる。また、光フアイバ心線２ａの側を検査
する場合は、ＯＴＤＲ測定器１３′ を、プラグ１１
’ を有するピグテール１２゛ を介して光学部材
４の端子りに接続すればよい。このとき、前述のように
通信用の信号光と検査用の信号光とは互いに波長が異な
っているので、使用回線の通信を中断することなく光信
号線路の保守作業を行う事が出来る。○When performing TDR measurement, an OTDR measuring device 13 that performs measurement using an optical signal of wavelength λ2 is connected to the C terminal of the optical member 4 via a pigtail 12 having a plug 11. Tests can be carried out. When inspecting the optical fiber 2a side, the OTDR measuring device 13' is connected to the plug 11.
It may be connected to the terminal of the optical member 4 via a pigtail 12' having a . At this time, as described above, since the communication signal light and the inspection signal light have different wavelengths, maintenance work on the optical signal line can be performed without interrupting the communication of the line in use.
本発明者等は、外径１２５μｍの１６３μｍ用単−モー
ドファイバ（１０Ｋｍｘ２）を光信号線路とし、１．３
μｍの波長の信号光を用いた通信回線に、分波フィルタ
ーによって構成した分波・合波器を挿入し、１．５５μ
ｍの波長の検査用信号を出力するレーザダイオードを用
いたＯＴＤＲ測定器を接続して、ＯＴＤＲ法による検査
を実施した。The present inventors used a 163 μm single-mode fiber (10 km x 2) with an outer diameter of 125 μm as an optical signal line, and
A demultiplexer/combiner composed of a demultiplexing filter is inserted into a communication line that uses signal light with a wavelength of μm, and
An OTDR measuring device using a laser diode that outputs a test signal with a wavelength of m was connected to perform the test using the OTDR method.
尚、シングルモードファイバにより光線路が構成されて
いるので、局部的な曲げ損失等の波長依存する損失の発
生個所の標定に対して有利となるように、通信波長より
試験波長を長く選択して伝送路の■パラメータが小さく
なるようにした。In addition, since the optical path is composed of a single mode fiber, the test wavelength is selected to be longer than the communication wavelength to be advantageous in locating the location where wavelength-dependent loss such as local bending loss occurs. The ■parameter of the transmission path has been made smaller.
即ち、■パラメータが小さくなることにより、放射損失
は同−曲げ径に対して大きくなるので、高感度な極部異
常検出が可能となるからである。That is, as the parameter (1) becomes smaller, the radiation loss becomes larger for the same bending diameter, making it possible to detect extreme abnormalities with high sensitivity.
上述のような設定で、試験側の光フアイバ心線に部分的
な曲げ損失を与え、後方散乱光レベルの変化よりその位
置を標定したところ、±１０ｍの精度で標定できた。こ
の標定精度は、通信を中断して光信号線路をＯＴＤＲ試
験器に直接接続して行う従来の試験と同等のものである
。With the above settings, a partial bending loss was applied to the optical fiber on the test side, and the position was determined based on changes in the level of backscattered light, and the position could be determined with an accuracy of ±10 m. This location accuracy is equivalent to the conventional test performed by interrupting communication and directly connecting the optical signal line to the OTDR tester.
更に、分波合波器４のＣ端子あるいはＤ端子に光パワー
メータを接続し、光信号線路を伝播する信号光の一部を
取出すことによって信号光を間接的にモニターすること
ができた。これは、光信号線路に挿入した光学部材が、
通信用信号光の波長についてはＡ−Ｄ端子間およびＢ−
Ｃｍ壬子間結合は概念上は存在しないが、実際には一２
０ｄＢ程度のレベルで結合が存在しているためである。Furthermore, by connecting an optical power meter to the C terminal or D terminal of the demultiplexer/multiplexer 4 and extracting a portion of the signal light propagating through the optical signal line, the signal light could be indirectly monitored. This means that the optical member inserted into the optical signal line
Regarding the wavelength of the communication signal light,
Conceptually, there is no Cm connection, but in reality it is 12
This is because coupling exists at a level of about 0 dB.
１ｙｐ層】
以上述べたように、本発明に従う光信号線路の保守方法
では、光信号線路に予め検査用の光信号を注入および抽
出する手段を挿入しておき、この手段を利用して、通信
用光信号とは異なる波長の信号光によって検査を実施す
る。[1yp layer] As described above, in the optical signal line maintenance method according to the present invention, a means for injecting and extracting an optical signal for inspection is inserted into the optical signal line in advance, and using this means, communication Inspection is performed using signal light with a wavelength different from that of the optical signal used.
従って、その光信号線路の通信用信号光と互いに干渉す
ることがないので、その回線の通信を中断することなく
光信号による検査を実施することができる。また、通信
用信号光と波長が異なってさえいれば、検査用信号光の
波長の選択は自由であり、その検査に最も有利な波長を
選択することができる。Therefore, since there is no mutual interference with the communication signal light of the optical signal line, inspection using optical signals can be carried out without interrupting the communication of the line. Further, the wavelength of the inspection signal light can be freely selected as long as the wavelength is different from that of the communication signal light, and the most advantageous wavelength for the inspection can be selected.
こうして、本発明の方法に従って、その回線の通信を中
断することなくその回線の検査、モニタ等が可能になれ
ば、通信の途絶が許されない加入者系の通信回線にも光
通信技術を適用することが可能になり、光通信の先進性
を広く利用することが可能となる。In this way, according to the method of the present invention, if it becomes possible to inspect, monitor, etc. without interrupting communication on the line, optical communication technology can also be applied to subscriber-based communication lines where interruption of communication is not allowed. This makes it possible to widely utilize the advanced features of optical communications.
第１図は、本発明に従う光通信線路の保守方法を実施す
る際に有利に利用することのできる光学部材の構成並び
に配置を概略的に示す図である。
〔主な参照番号〕
ｌａ、ｌｂ・・・光ケーブル、
２ａ、２ｂ・・・光フアイバ心線、
３ａ、 ３ｂ、 １１．１１’ ・・プラグ、４・・・
・・・・光学部材、FIG. 1 is a diagram schematically showing the structure and arrangement of optical members that can be advantageously used when implementing the optical communication line maintenance method according to the present invention. [Main reference numbers] la, lb...optical cable, 2a, 2b...optical fiber core wire, 3a, 3b, 11.11'...plug, 4...
...optical components,
Claims (4)
、該光信号の波長とは異なる第２波長の光信号を注入並
びに抽出する手段を挿入し、 前記第１波長の光信号による通信を途絶することなく、
前記第２波長の光信号を用いて光伝送路の状態を検査す
ることを特徴とする光信号線路の保守方法。(1) A means for injecting and extracting an optical signal of a second wavelength different from the wavelength of the optical signal is inserted into an optical signal line that transmits an optical signal of a predetermined first wavelength, and an optical signal of the first wavelength is inserted. without interruption of communication by
A method for maintaining an optical signal line, comprising inspecting the condition of the optical transmission line using the optical signal of the second wavelength.
成されており、前記第２波長が前記第１波長よりも長い
ことを特徴とする１項記載の光信号線路の保守方法。(2) The method for maintaining an optical signal line according to item 1, wherein the optical signal line is constituted by a single mode fiber, and the second wavelength is longer than the first wavelength.
を用いたＯＴＤＲ法であることを特徴とする特許請求の
範囲第１項または第２項に記載の光信号線路の保守方法
。(3) The method for maintaining an optical signal line according to claim 1 or 2, wherein the inspection of the optical signal line is an OTDR method using an optical signal of the second wavelength. .
る光信号の光パワーのモニタであることを特徴とする特
許請求の範囲第１項または第２項に記載の光信号線路の
保守方法。(4) The optical signal line according to claim 1 or 2, wherein the inspection of the optical signal line is monitoring the optical power of the optical signal propagating on the optical signal line. Maintenance method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61313611A JPS63160436A (en) | 1986-12-24 | 1986-12-24 | Maintenance method for optical signal line |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61313611A JPS63160436A (en) | 1986-12-24 | 1986-12-24 | Maintenance method for optical signal line |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63160436A true JPS63160436A (en) | 1988-07-04 |
Family
ID=18043400
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61313611A Pending JPS63160436A (en) | 1986-12-24 | 1986-12-24 | Maintenance method for optical signal line |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63160436A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997024822A1 (en) * | 1995-12-28 | 1997-07-10 | Mci Communications Corporation | Method and system for detecting optical faults within the optical domain of a fiber communication network |
| US11067110B2 (en) | 2010-05-05 | 2021-07-20 | Beckman Coulter, Inc. | Device coupling for a motor |
-
1986
- 1986-12-24 JP JP61313611A patent/JPS63160436A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997024822A1 (en) * | 1995-12-28 | 1997-07-10 | Mci Communications Corporation | Method and system for detecting optical faults within the optical domain of a fiber communication network |
| US11067110B2 (en) | 2010-05-05 | 2021-07-20 | Beckman Coulter, Inc. | Device coupling for a motor |
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