JP2000031902A - Optical transmission line and optical transmission system - Google Patents
Optical transmission line and optical transmission systemInfo
- Publication number
- JP2000031902A JP2000031902A JP10194379A JP19437998A JP2000031902A JP 2000031902 A JP2000031902 A JP 2000031902A JP 10194379 A JP10194379 A JP 10194379A JP 19437998 A JP19437998 A JP 19437998A JP 2000031902 A JP2000031902 A JP 2000031902A
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- Japan
- Prior art keywords
- optical
- dispersion
- signal light
- transmission
- chromatic dispersion
- Prior art date
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- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
- Optical Communication System (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、光伝送路及び光伝
送システムに関し、より具体的には、信号光の累積波長
分散を補償する分散補償媒質を具備する光伝送路及びそ
の光伝送路を使用する光伝送システムに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission line and an optical transmission system, and more particularly, to an optical transmission line having a dispersion compensating medium for compensating the accumulated chromatic dispersion of signal light, and an optical transmission line having the same. It relates to an optical transmission system to be used.
【０００２】[0002]
【従来の技術】伝送速度が４０Ｇｂｉｔ／ｓ以上の高速
光信号を、大平洋を横断するほどに長い距離伝送する長
距離光伝送システムでは、タイミングジッタの許容値が
非常に小さく、これを抑制する伝送制御技術が重要であ
る。2. Description of the Related Art In a long-distance optical transmission system for transmitting a high-speed optical signal having a transmission speed of 40 Gbit / s or more over a long distance so as to cross the Pacific Ocean, the allowable value of the timing jitter is very small and is suppressed. Transmission control technology is important.
【０００３】タイミング・ジッタを抑制する方法とし
て、伝送信号光に同期して動作する光変調器を２Ｒ（Ｒ
ｅｔｉｍｉｎｇ及びＲｅｓｈａｐｉｎｇ）中継器として
伝送路に所定の間隔で挿入し、伝送信号光を時間軸上で
再生（リタイミング及びリシェーピング）する方法が知
られている。しかし、この方法は、高速光変調器及びそ
の駆動回路を光中継器に含むので、超高速化への対応は
困難である。更には、高信頼性の要求される海底ケーブ
ル等への適用は困難である。As a method of suppressing timing jitter, an optical modulator operating in synchronization with a transmission signal light has a 2R (R)
There is known a method in which a transmission signal light is reproduced (retiming and reshaping) on a time axis by inserting the transmission signal light into a transmission line at predetermined intervals as an intermediary device (estimating and reshaping). However, since this method includes the high-speed optical modulator and its driving circuit in the optical repeater, it is difficult to cope with ultra-high speed. Furthermore, it is difficult to apply to submarine cables and the like that require high reliability.
【０００４】別の方法として、スライディング・ガイデ
ィング・フィルタ法が知られている。この方法では、光
伝送路中に光フィルタを挿入し、ランダム周波数シフト
を周波数領域で制御する。この方法で伝送特性を大幅に
改善するには、非常に狭い帯域幅を有する光バンドバス
フィルタの中心周波数を距離と共に僅かにスライドさせ
る必要がある。しかし、現在の技術レベル実際の光伝送
システムの温度変化などの環境変化を考慮すると、狭帯
域光フィルタの精密制御は実際の光伝送システムではほ
ぼ不可能と予想される。光伝送システムの長期的な信頼
性などの実用的観点からも、適した方法ではない。更に
は、この方法を用いた４０Ｇｂｉｔ／ｓ光伝送の報告例
では、伝送距離は４０００ｋｍ程度に制限されており、
距離的に不十分である。[0004] As another method, a sliding guiding filter method is known. In this method, an optical filter is inserted into an optical transmission line, and a random frequency shift is controlled in a frequency domain. To significantly improve the transmission characteristics by this method, it is necessary to slightly slide the center frequency of an optical bandpass filter having a very narrow bandwidth with distance. However, in consideration of environmental changes such as a temperature change of an actual optical transmission system at the present technology level, it is expected that precise control of a narrow band optical filter is almost impossible in an actual optical transmission system. It is not a suitable method from a practical viewpoint such as long-term reliability of the optical transmission system. Furthermore, in a report example of 40 Gbit / s optical transmission using this method, the transmission distance is limited to about 4000 km,
Insufficient distance.
【０００５】更に、伝送用光ファイバの累積波長分散値
に応じて所要の間隔で分散補償媒質を挿入し、伝送系の
平均波長分散値を零近傍とすることで、タイミングジッ
タを抑圧する方法も報告されている。この方法は、伝送
路中で複雑な制御を行うこと無しにタイミングジッタを
抑圧できるが、４０Ｇｂｉｔ／ｓ以上の高速信号の長距
離伝送を目的とした伝送用光ファイバの波長分散値、及
び分散補償媒質の分散補償量に関する詳細な検討は行わ
れていない。Further, there is also a method of inserting a dispersion compensating medium at required intervals in accordance with the accumulated chromatic dispersion value of the transmission optical fiber and setting the average chromatic dispersion value of the transmission system near zero, thereby suppressing timing jitter. It has been reported. Although this method can suppress timing jitter without performing complicated control in a transmission line, the chromatic dispersion value and dispersion compensation of a transmission optical fiber for long-distance transmission of a high-speed signal of 40 Gbit / s or more are provided. No detailed study has been made on the dispersion compensation amount of the medium.
【０００６】[0006]
【発明が解決しようとする課題】このように、４０Ｇｂ
ｉｔ／ｓ以上の高速信号を６０００ｋｍ以上にわたる超
長距離伝送させる場合に、タイミング・ジッタを抑制で
きる好ましい構成がいまだ提案されていない。As described above, 40 Gb
When transmitting a high-speed signal of at least it / s over an ultra-long distance over 6000 km, a preferable configuration capable of suppressing timing jitter has not yet been proposed.
【０００７】本発明は、このように高速信号の超長距離
伝送でタイミング・ジッタを効果的に抑制できる光伝送
路及び光伝送システムを提示することを目的とする。An object of the present invention is to provide an optical transmission line and an optical transmission system capable of effectively suppressing timing jitter in ultra-long distance transmission of a high-speed signal.
【０００８】[0008]
【課題を解決するための手段】本発明では、光伝送路
が、複数の伝送用光ファイバと、当該信号光を増幅する
１以上の光増幅手段と、適当な間隔で設置され、当該信
号光の累積波長分散を補償する分散補償媒質とからな
り、当該分散補償媒質の波長分散補償量の絶対値が１０
ｐｓ／ｎｍから４０ｐｓ／ｎｍの範囲にあるか、及び／
又は、伝送用光ファイバの波長分散値の絶対値を０．２
３ｐｓ／ｎｍ／ｋｍ以上とする。According to the present invention, an optical transmission line is provided at appropriate intervals with a plurality of transmission optical fibers and one or more optical amplification means for amplifying the signal light. And a dispersion compensating medium for compensating for the accumulated chromatic dispersion of the dispersion compensating medium.
between ps / nm and 40 ps / nm, and / or
Alternatively, the absolute value of the chromatic dispersion value of the transmission optical fiber is set to 0.2.
3 ps / nm / km or more.
【０００９】分散補償媒質の波長分散補償量及び／又は
伝送用光ファイバの波長分散値のをこのように規定する
ことで、４０Ｇｂｉｔ／ｓ以上の信号光を６０００ｋｍ
以上の長距離にわたり伝送することが可能になる。By defining the chromatic dispersion compensation amount of the dispersion compensating medium and / or the chromatic dispersion value of the transmission optical fiber as described above, signal light of 40 Gbit / s or more can be transmitted at 6000 km.
It is possible to transmit over the above long distance.
【００１０】分散補償媒質は、信号光の累積波長分散を
必ずしもゼロに補償する必要はなく、ゼロ近傍に補償す
ればよい。これでも、初期の目的を達成できる。分散補
償媒質の分散補償量の制限が緩くても良いので、実際の
伝送路設計及び敷設が容易になる。The dispersion compensating medium does not necessarily need to compensate for the accumulated chromatic dispersion of the signal light to zero, but may compensate for it near zero. Even with this, the initial purpose can be achieved. Since the restriction on the dispersion compensation amount of the dispersion compensation medium may be loose, the actual transmission line design and installation can be facilitated.
【００１１】信号光は、リターンゼロ光パルス、即ち、
ＲＺ光パルス又はソリトン・パルスからなる。The signal light is a return zero light pulse, that is,
It consists of an RZ light pulse or a soliton pulse.
【００１２】伝送用光ファイバが波長に対して一定の波
長分散値を具備することにより、波長分割多重伝送シス
テムで、各波長の累積波長分散の補償設計が容易にな
り、単一波長伝送システムの場合と同様にタイミング・
ジッタを抑圧でき、同様の伝送特性を実現できる。Since the transmission optical fiber has a constant chromatic dispersion value with respect to the wavelength, it becomes easy to design a compensation for the accumulated chromatic dispersion of each wavelength in the wavelength division multiplexing transmission system, and to realize a single wavelength transmission system. Timing as in the case
Jitter can be suppressed and the same transmission characteristics can be realized.
【００１３】分散補償媒質が伝送用光ファイバの累積波
長分散の波長による差異をキャンセルする分散スロープ
特性を具備することで、波長分割多重伝送システムでも
各波長の累積波長分散を補償しやすくなり、単一波長伝
送システムの場合と同様にタイミング・ジッタを抑圧で
き、同様の伝送特性を実現できる。Since the dispersion compensating medium has a dispersion slope characteristic for canceling the difference due to the wavelength of the accumulated chromatic dispersion of the transmission optical fiber, it is easy to compensate the accumulated chromatic dispersion of each wavelength even in the wavelength division multiplexing transmission system. As with the one-wavelength transmission system, timing jitter can be suppressed, and similar transmission characteristics can be realized.
【００１４】[0014]
【実施例】以下、図面を参照して、本発明の実施例を詳
細に説明する。Embodiments of the present invention will be described below in detail with reference to the drawings.
【００１５】図１は、本発明の一実施例の概略構成ブロ
ック図を示す。光送信装置１０は、光パルス幅８ｐｓの
光ソリトンによる４０Ｇｂｉｔ／ｓの信号光を光伝送路
１２に出力する。実際には、光パルス幅８ｐｓの光ソリ
トン・パルスを１０Ｇｂｉｔ／ｓでデータ変調（ＰＮ１
５段）し、２段階で光時間軸多重により４０Ｇｂｉｔ／
ｓの信号光を生成した。伝送特性を向上させるための位
相変調と、光中継器の偏波ホールバーニングを抑制する
ための偏波スクランブルが施されている。FIG. 1 is a schematic block diagram showing an embodiment of the present invention. The optical transmitter 10 outputs 40 Gbit / s signal light to the optical transmission line 12 using an optical soliton having an optical pulse width of 8 ps. Actually, an optical soliton pulse having an optical pulse width of 8 ps is subjected to data modulation (PN1) at 10 Gbit / s.
5 steps), and 40Gbit /
s signal light was generated. Phase modulation for improving transmission characteristics and polarization scrambling for suppressing polarization hole burning of the optical repeater are performed.
【００１６】光伝送路１２では、多数の伝送用光ファイ
バ（分散シフトファイバ）１４が光増幅器１６によりシ
リアル接続し、適宜の間隔で分散補償ファイバ１８が挿
入されている。分散補償ファイバ１８は、伝送用光ファ
イバ１４による累積波長分散を波長分散値０付近に削減
する素子である。In the optical transmission line 12, a number of transmission optical fibers (dispersion shift fibers) 14 are serially connected by an optical amplifier 16, and dispersion compensation fibers 18 are inserted at appropriate intervals. The dispersion compensating fiber 18 is an element for reducing the accumulated chromatic dispersion caused by the transmission optical fiber 14 to a value near the chromatic dispersion value 0.
【００１７】光送信装置１０から出力された信号光は、
光増幅器１６により光増幅され、伝送用光ファイバ１４
及び分散補償ファイバ１８で減衰する。光送信装置１０
から出力された信号光はまた、伝送用光ファイバ１４で
は波長分散が累積し、その累積波長分散が分散補償ファ
イバ１８によりゼロ近辺にまで削減される。信号光は、
このような減衰と増幅及び波長分散の累積と補償を繰り
返して光伝送路１２を伝搬し、光受信装置２０に入力す
る。光受信装置２０は、入力した信号光からデータを復
元する。The signal light output from the optical transmitter 10 is
The optical fiber 16 is optically amplified by the optical amplifier 16 and transmitted.
And is attenuated by the dispersion compensating fiber 18. Optical transmission device 10
Of the signal light output from the transmission optical fiber 14, the chromatic dispersion is accumulated, and the accumulated chromatic dispersion is reduced to near zero by the dispersion compensating fiber 18. The signal light is
By repeating such attenuation and amplification and accumulation and compensation of chromatic dispersion, the light propagates through the optical transmission line 12 and is input to the optical receiver 20. The optical receiver 20 restores data from the input signal light.
【００１８】詳細は後述するが、本実施例では、伝送用
光ファイバ１４は、その長さが３５ｋｍ、波長分散は信
号波長（１５５２．８ｎｍ）で０．２３ｐｓ／ｎｍ／ｋ
ｍ以上である。分散補償ファイバ１８の分散補償量は、
１０ｐｓ／ｎｍ乃至４０ｐｓ／ｎｍである。Although details will be described later, in this embodiment, the transmission optical fiber 14 has a length of 35 km and a chromatic dispersion of 0.23 ps / nm / k at the signal wavelength (1552.8 nm).
m or more. The dispersion compensation amount of the dispersion compensating fiber 18 is
It is 10 ps / nm to 40 ps / nm.
【００１９】１４０ｋｍの周回伝送システムでその特性
を調べた。周回伝送路の構成を図２に示す。図１と同じ
構成要素には同じ符号を付してある。伝送用光ファイバ
１４はその長さが３５ｋｍで、その２スパン毎に分散補
償ファイバ１８を挿入した。光増幅器１６は、９８０ｎ
ｍ励起のエルビウムドープ光ファイバ増幅器からなる。
図２に示すように、１４０ｋｍの周回伝送系は、３５ｋ
ｍの伝送用光ファイバ１４が４スパン、分散補償ファイ
バ１８が２スプール、９８０ｎｍ励起エルビウムドープ
光ファイバ増幅器１６が５台、更に、半値幅５ｎｍの光
バンドパスフィルタからなる。The characteristics were examined with a 140 km loop transmission system. FIG. 2 shows the configuration of the loop transmission path. The same components as those in FIG. 1 are denoted by the same reference numerals. The transmission optical fiber 14 had a length of 35 km, and a dispersion compensating fiber 18 was inserted every two spans. The optical amplifier 16 is 980n
It consists of an m-pumped erbium-doped optical fiber amplifier.
As shown in FIG. 2, the 140 km loop transmission system is
The transmission optical fiber 14 of m is composed of four spans, the dispersion compensating fiber 18 is composed of two spools, the 980 nm pumped erbium-doped optical fiber amplifier 16 is composed of five units, and furthermore, the optical band-pass filter has a half width of 5 nm.
【００２０】図３は、周回伝送路の分散マップの一例を
示す。横軸は距離、縦軸は累積波長分散を示す。伝送用
光ファイバ１４の波長分散は０．２９ｐｓ／ｎｍ／ｋｍ
であり、分散補償ファイバ１８の分散補償量は、一方が
２６ｐｓ／ｎｍ、他方が１１ｐｓ／ｎｍである。２スパ
ン毎に分散補償ファイバ１８により累積波長分散を補償
することで、周回伝送路の平均分散値は０．０２８ｐｓ
／ｎｍ／ｋｍまで低減されている。図４は、測定された
符号誤り率（ＢＥＲ）の伝送距離依存性を示す。但し、
図４で示すＢＥＲは、光時分割多重された４チャンネル
の１０Ｇｂｉｔ／ｓ信号に対する測定値の平均である。FIG. 3 shows an example of a dispersion map of the loop transmission line. The horizontal axis represents distance, and the vertical axis represents cumulative chromatic dispersion. The chromatic dispersion of the transmission optical fiber 14 is 0.29 ps / nm / km.
The dispersion compensation amount of the dispersion compensating fiber 18 is 26 ps / nm on one side and 11 ps / nm on the other side. By compensating the accumulated chromatic dispersion by the dispersion compensating fiber 18 every two spans, the average dispersion value of the loop transmission line is 0.028 ps.
/ Nm / km. FIG. 4 shows the transmission distance dependency of the measured bit error rate (BER). However,
The BER shown in FIG. 4 is the average of the measured values for 10 Gbit / s signals of four channels that are optical time division multiplexed.
【００２１】分散補償ファイバ１８として種々の波長分
散のものを使用して、符号誤り率が１０−９になる伝送
距離を求めた。その結果を、図５に示す。横軸は、分散
補償ファイバ１８の分散補償量、縦軸は符号誤り率が１
０−９になる伝送距離を示す。このとき、伝送速度は４
０Ｇｂｉｔ／ｓ、伝送用光ファイバ１４の波長分散は
０．３０ｐｓ／ｎｍ／ｋｍである。これから、分散補償
ファイバ１８の分散補償量としては、１０ｐｓ／ｎｍ乃
至４０ｐｓ／ｎｍが好ましいことが分かる。勿論、伝送
用光ファイバ１４の波長分散が負であれば、分散補償フ
ァイバ１８の分散補償量は正になり、伝送用光ファイバ
１４の波長分散が正であれば、分散補償ファイバ１８の
分散補償量は負になる。Using a dispersion compensating fiber 18 having various wavelength dispersions, the transmission distance at which the code error rate is 10 −9 was obtained. The result is shown in FIG. The horizontal axis indicates the amount of dispersion compensation of the dispersion compensating fiber 18, and the vertical axis indicates that the bit error rate is 1.
0 indicating the transmission distance becomes -9. At this time, the transmission speed is 4
0 Gbit / s, and the chromatic dispersion of the transmission optical fiber 14 is 0.30 ps / nm / km. This indicates that the dispersion compensation amount of the dispersion compensation fiber 18 is preferably 10 ps / nm to 40 ps / nm. Of course, if the chromatic dispersion of the transmission optical fiber 14 is negative, the dispersion compensation amount of the dispersion compensating fiber 18 becomes positive. If the chromatic dispersion of the transmission optical fiber 14 is positive, the dispersion compensation of the dispersion compensating fiber 18 is performed. The amount will be negative.
【００２２】分散補償ファイバ１８の分散補償量として
上述の好ましい範囲内の中間的な値１９ｐｓ／ｎｍを採
用した場合に、伝送用控え理ファイバ１４の波長分散値
としてどの程度が好ましいのかも調べた。その結果を図
６に示す。横軸は、伝送用光ファイバ１４の波長分散値
（ｐｓ／ｎｍ／ｋｍ）、縦軸は、符号誤り率が１０− ９
になる伝送距離を示す。図６から、伝送距離６０００ｋ
ｍ以上を目指す場合には、伝送用光ファイバ１４の波長
分散は、０．２３ｐｓ／ｎｍ／ｋｍ以上であればよいこ
とが分かる。When the intermediate value of 19 ps / nm within the above-mentioned preferable range is adopted as the dispersion compensation amount of the dispersion compensating fiber 18, it is also examined how much the chromatic dispersion value of the transmission restraining fiber 14 is preferable. . FIG. 6 shows the result. The horizontal axis is the wavelength dispersion value of the transmission optical fiber 14 (ps / nm / km) , and the vertical axis indicates the bit error rate is 10 - 9
Indicates the transmission distance. From Fig. 6, the transmission distance is 6000k
When aiming at m or more, it is understood that the chromatic dispersion of the transmission optical fiber 14 may be 0.23 ps / nm / km or more.
【００２３】このように、分散補償間隔を短くすると共
に、波長分散媒質の分散補償量と伝送用光ファイバの波
長分散を適切に選択することで、伝送特性が向上し、伝
送距離８６００ｋｍ以上で、１０−９以下のＢＥＲを達
成できた。As described above, by shortening the dispersion compensation interval and appropriately selecting the dispersion compensation amount of the chromatic dispersion medium and the chromatic dispersion of the transmission optical fiber, the transmission characteristics are improved, and when the transmission distance is 8600 km or more, A BER of 10 −9 or less was achieved.
【００２４】上記実施例では、伝送用光ファイバ１４の
分散値を正、分散補償媒質（分散補償ファイバ１８）の
分散値を負として、伝送系全体の平均分散値を零近傍に
設定しているが、伝送用光ファイバ１４の分散値を負、
分散補償媒質（分散補償ファイバ１８）の分散値を正と
して、伝送系全体の平均分散値を零近傍に設定する場合
にも、同様の効果が得られることは明らかである。In the above embodiment, the dispersion value of the transmission optical fiber 14 is positive, the dispersion value of the dispersion compensating medium (dispersion compensating fiber 18) is negative, and the average dispersion value of the entire transmission system is set near zero. Has a negative dispersion value of the transmission optical fiber 14,
It is apparent that the same effect can be obtained when the dispersion value of the dispersion compensating medium (dispersion compensating fiber 18) is positive and the average dispersion value of the entire transmission system is set near zero.
【００２５】単一波長伝送の場合を例に説明したが、こ
れを波長分割多重伝送システムにも適用できることは明
らかである。各波長毎に、伝送用光ファイバ１４と分散
補償ファイバ１８の条件を満たすかようにシステムを設
計すればよい。その場合、例えば、波長に対して一定の
波長分散値を有する分散フラット・ファイバを伝送用光
ファイバ１４として用いることで、波長分割多重伝送シ
ステムにおける各波長の信号光に対して、単一波長伝送
の場合と同様の伝送特性を達成できる。Although the case of single wavelength transmission has been described as an example, it is apparent that this can be applied to a wavelength division multiplex transmission system. The system may be designed to satisfy the conditions of the transmission optical fiber 14 and the dispersion compensating fiber 18 for each wavelength. In this case, for example, by using a dispersion flat fiber having a constant chromatic dispersion value with respect to the wavelength as the transmission optical fiber 14, a single wavelength transmission is performed for the signal light of each wavelength in the wavelength division multiplex transmission system. Can achieve the same transmission characteristics as in the case of
【００２６】また、伝送用光ファイバの分散スロープ
（波長に対する波長分散値の変化）が有限である場合、
分散補償媒質として伝送用光ファイバの累積波長分散の
波長による差異をキャンセルするような分散スロープ特
性を有するものを用いることで、波長分割多重伝送シス
テムにおける各波長の累積分散補償が容易になり、単一
波長伝送と同様の伝送特性を実現できる。例えば、波長
分割多重信号光のチャンネル間の波長間隔が１．５ｎ
ｍ、伝送用光ファイバの分散スロープが０．０７ｐｓ／
ｎｍ／ｎｍ／ｋｍ、光増幅器の中継間隔が３５ｋｍの場
合、最も波長分散の小さい波長（ｃｈ１）の波長分散を
０．２９ｐｓ／ｎｍ／ｋｍに設定することにより、ｃｈ
１とｃｈ８の中継間隔毎の累積波長分散値はそれぞれ１
０ｐｓ／ｎｍ及び３５．７ｐｓ／ｎｍとなり、４０Ｇｂ
ｉｔ／ｓの８波長多重伝送による太洋横断距離の伝送が
可能になる。When the dispersion slope (change in chromatic dispersion with respect to wavelength) of the transmission optical fiber is finite,
By using a dispersion compensating medium having a dispersion slope characteristic that cancels out the difference due to the wavelength of the accumulated chromatic dispersion of the transmission optical fiber, the accumulated dispersion compensation of each wavelength in the wavelength division multiplexing transmission system can be easily performed. Transmission characteristics similar to one-wavelength transmission can be realized. For example, the wavelength interval between channels of the wavelength division multiplexed signal light is 1.5 n
m, the dispersion slope of the transmission optical fiber is 0.07 ps /
In the case of nm / nm / km and the relay interval between the optical amplifiers is 35 km, the chromatic dispersion of the wavelength (ch1) having the smallest chromatic dispersion is set to 0.29 ps / nm / km.
The cumulative chromatic dispersion values for each relay interval of 1 and ch8 are 1
0ps / nm and 35.7ps / nm, 40Gb
It is possible to transmit the transoceanic distance by it / s 8-wavelength multiplex transmission.
【００２７】[0027]
【発明の効果】以上の説明から容易に理解できるよう
に、本発明によれば、４０Ｇｂｉｔ／ｓというような高
速の信号光を６０００ｋｍを越える長距離にわたって一
定化の符号誤り率で伝送することができる。アクティブ
素子を使用しないので、長期の信頼性も確保できる。As can be easily understood from the above description, according to the present invention, a high-speed signal light such as 40 Gbit / s can be transmitted at a constant code error rate over a long distance exceeding 6000 km. it can. Since no active element is used, long-term reliability can be ensured.
【図１】 本発明の一実施例の概略構成ブロック図であ
る。FIG. 1 is a schematic block diagram of an embodiment of the present invention.
【図２】 本実施例の実証する周回伝送システムの概略
構成ブロック図である。FIG. 2 is a schematic configuration block diagram of a loop transmission system demonstrated in the present embodiment.
【図３】 図２に示すシステムでの分散マップである。FIG. 3 is a dispersion map in the system shown in FIG. 2;
【図４】 図２に示す周回伝送システムでの符号誤り率
特性である。FIG. 4 shows a code error rate characteristic in the loop transmission system shown in FIG. 2;
【図５】 分散補償ファイバ１８の分散補償量に対する
伝送距離の測定結果である。FIG. 5 is a measurement result of a transmission distance with respect to a dispersion compensation amount of the dispersion compensating fiber 18;
【図６】伝送用光ファイバ１４の波長分散値に対する伝
送距離の測定結果である。FIG. 6 shows a measurement result of a transmission distance with respect to a chromatic dispersion value of the transmission optical fiber 14;
１０：光送信装置 １２：光伝送路 １４：伝送用光ファイバ（分散シフトファイバ） １６：光増幅器 １８：分散補償ファイバ ２０：光受信装置 10: Optical transmitter 12: Optical transmission line 14: Optical fiber for transmission (dispersion shift fiber) 16: Optical amplifier 18: Dispersion compensating fiber 20: Optical receiver
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ テーマコート゛(参考） Ｈ０４Ｂ 10/135 10/13 10/12 (72)発明者 枝川 登 東京都新宿区西新宿２丁目３番２号国際電 信電話株式会社内 (72)発明者 鈴木 正敏 東京都新宿区西新宿２丁目３番２号国際電 信電話株式会社内 Ｆターム(参考） 5K002 AA01 AA03 AA06 BA04 CA01 CA13 FA02 GA10 ──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. 7 Identification symbol FI Theme Court ゛ (Reference) H04B 10/135 10/13 10/12 (72) Inventor Noboru Egawa 2-3-2 Nishishinjuku, Shinjuku-ku, Tokyo No. 2 International Telegraph and Telephone Corporation (72) Inventor Masatoshi Suzuki 2-3-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo F-term in International Telegraph and Telephone Corporation (reference)
Claims (22)
る光伝送路であって、 複数の伝送用光ファイバと、 当該信号光を増幅する１以上の光増幅手段と、 適当な間隔で設置され、当該信号光の累積波長分散を補
償する分散補償媒質とからなり、当該分散補償媒質の波
長分散補償量の絶対値が１０ｐｓ／ｎｍから４０ｐｓ／
ｎｍの範囲にあることを特徴とする光伝送路。1. An optical transmission line for transmitting signal light of 40 Gbit / s or more, comprising: a plurality of transmission optical fibers; and at least one optical amplifying means for amplifying the signal light; And a dispersion compensating medium for compensating the accumulated chromatic dispersion of the signal light, and the absolute value of the chromatic dispersion compensation amount of the dispersion compensating medium is 10 ps / nm to 40 ps / nm.
An optical transmission line characterized by being in the range of nm.
対値が０．２３ｐｓ／ｎｍ／ｋｍ以上である請求項１に
記載の光伝送路。2. The optical transmission line according to claim 1, wherein the absolute value of the chromatic dispersion value of the transmission optical fiber is 0.23 ps / nm / km or more.
波長分散をゼロ近傍に補償する請求項１に記載の光伝送
路。3. The optical transmission line according to claim 1, wherein the dispersion compensating medium compensates for the accumulated chromatic dispersion of the signal light near zero.
らなる請求項１に記載の光伝送路。4. The optical transmission line according to claim 1, wherein the signal light comprises a return zero light pulse.
一定の波長分散値を具備する請求項１に記載の光伝送
路。5. The optical transmission line according to claim 1, wherein the transmission optical fiber has a constant chromatic dispersion value with respect to a wavelength.
イバの累積波長分散の波長による差異をキャンセルする
分散スロープ特性を具備する請求項１に記載の光伝送
路。6. The optical transmission line according to claim 1, wherein the dispersion compensating medium has a dispersion slope characteristic for canceling a difference due to a wavelength of the accumulated chromatic dispersion of the transmission optical fiber.
る光伝送路であって、 複数の伝送用光ファイバと、 当該信号光を増幅する１以上の光増幅手段と、 適当な間隔で設置され、当該信号光の累積波長分散を補
償する分散補償媒質とからなり、当該伝送用光ファイバ
の波長分散値の絶対値が０．２３ｐｓ／ｎｍ／ｋｍ以上
であることを特徴とする光伝送路。7. An optical transmission line for transmitting signal light of 40 Gbit / s or more, comprising: a plurality of transmission optical fibers; one or more optical amplifying means for amplifying the signal light; An optical transmission line comprising a dispersion compensating medium for compensating the accumulated chromatic dispersion of the signal light, wherein the absolute value of the chromatic dispersion value of the transmission optical fiber is 0.23 ps / nm / km or more.
波長分散をゼロ近傍に補償する請求項７に記載の光伝送
路。8. The optical transmission line according to claim 7, wherein the dispersion compensating medium compensates for the accumulated chromatic dispersion of the signal light near zero.
らなる請求項７に記載の光伝送路。9. The optical transmission line according to claim 7, wherein the signal light comprises a return zero light pulse.
て一定の波長分散値を具備する請求項７に記載の光伝送
路。10. The optical transmission line according to claim 7, wherein the transmission optical fiber has a constant chromatic dispersion value with respect to the wavelength.
ァイバの累積波長分散の波長による差異をキャンセルす
る分散スロープ特性を具備する請求項７に記載の光伝送
路。11. The optical transmission line according to claim 7, wherein the dispersion compensating medium has a dispersion slope characteristic for canceling a difference due to a wavelength of the accumulated chromatic dispersion of the transmission optical fiber.
する光送信装置と、当該信号光を受信する光受信装置
と、当該光送信装置から当該光受信装置に当該信号光を
伝送する光伝送路とからなる光伝送システムであって、
当該光伝送路が、 複数の伝送用光ファイバと、 当該信号光を増幅する１以上の光増幅手段と、 適当な間隔で設置され、当該信号光の累積波長分散を補
償する分散補償媒質とからなり、当該分散補償媒質の波
長分散補償量の絶対値が１０ｐｓ／ｎｍから４０ｐｓ／
ｎｍの範囲にあることを特徴とする光伝送システム。12. An optical transmitter for outputting a signal light of 40 Gbit / s or more, an optical receiver for receiving the signal light, and an optical transmission line for transmitting the signal light from the optical transmitter to the optical receiver. An optical transmission system comprising:
The optical transmission line is composed of a plurality of transmission optical fibers, one or more optical amplifying means for amplifying the signal light, and a dispersion compensating medium provided at an appropriate interval and compensating for the accumulated chromatic dispersion of the signal light. And the absolute value of the chromatic dispersion compensation amount of the dispersion compensation medium is 10 ps / nm to 40 ps / nm.
An optical transmission system characterized by being in the nm range.
絶対値が０．２３ｐｓ／ｎｍ／ｋｍ以上である請求項１
２に記載の光伝送システム。13. The transmission optical fiber according to claim 1, wherein the absolute value of the chromatic dispersion value is 0.23 ps / nm / km or more.
3. The optical transmission system according to 2.
積波長分散をゼロ近傍に補償する請求項１２に記載の光
伝送システム。14. The optical transmission system according to claim 12, wherein the dispersion compensating medium compensates for the accumulated chromatic dispersion of the signal light near zero.
からなる請求項１２に記載の光伝送システム。15. The optical transmission system according to claim 12, wherein the signal light comprises a return zero light pulse.
て一定の波長分散値を具備する請求項１２に記載の光伝
送システム。16. The optical transmission system according to claim 12, wherein the transmission optical fiber has a constant chromatic dispersion value with respect to a wavelength.
ァイバの累積波長分散の波長による差異をキャンセルす
る分散スロープ特性を具備する請求項１２に記載の光伝
送システム。17. The optical transmission system according to claim 12, wherein the dispersion compensating medium has a dispersion slope characteristic for canceling a difference due to a wavelength of the accumulated chromatic dispersion of the transmission optical fiber.
する光送信装置と、当該信号光を受信する光受信装置
と、当該光送信装置から当該光受信装置に当該信号光を
伝送する光伝送路とからなる光伝送システムであって、
当該光伝送路が、 複数の伝送用光ファイバと、 当該信号光を増幅する１以上の光増幅手段と、 適当な間隔で設置され、当該信号光の累積波長分散を補
償する分散補償媒質とからなり、当該伝送用光ファイバ
の波長分散値の絶対値が０．２３ｐｓ／ｎｍ／ｋｍ以上
であることを特徴とする光伝送システム。18. An optical transmitter for outputting signal light of 40 Gbit / s or more, an optical receiver for receiving the signal light, and an optical transmission line for transmitting the signal light from the optical transmitter to the optical receiver. An optical transmission system comprising:
The optical transmission line is composed of a plurality of transmission optical fibers, one or more optical amplifying means for amplifying the signal light, and a dispersion compensating medium provided at an appropriate interval and compensating for the accumulated chromatic dispersion of the signal light. An optical transmission system, wherein the absolute value of the chromatic dispersion value of the transmission optical fiber is 0.23 ps / nm / km or more.
積波長分散をゼロ近傍に補償する請求項１８に記載の光
伝送システム。19. The optical transmission system according to claim 18, wherein the dispersion compensating medium compensates for the accumulated chromatic dispersion of the signal light near zero.
からなる請求項１８に記載の光伝送システム。20. The optical transmission system according to claim 18, wherein the signal light comprises a return zero light pulse.
て一定の波長分散値を具備する請求項１８に記載の光伝
送システム。21. The optical transmission system according to claim 18, wherein the transmission optical fiber has a constant chromatic dispersion value with respect to a wavelength.
ァイバの累積波長分散の波長による差異をキャンセルす
る分散スロープ特性を具備する請求項１８に記載の光伝
送システム。22. The optical transmission system according to claim 18, wherein the dispersion compensating medium has a dispersion slope characteristic for canceling a difference due to a wavelength of the accumulated chromatic dispersion of the transmission optical fiber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10194379A JP2000031902A (en) | 1998-07-09 | 1998-07-09 | Optical transmission line and optical transmission system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10194379A JP2000031902A (en) | 1998-07-09 | 1998-07-09 | Optical transmission line and optical transmission system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000031902A true JP2000031902A (en) | 2000-01-28 |
Family
ID=16323627
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10194379A Pending JP2000031902A (en) | 1998-07-09 | 1998-07-09 | Optical transmission line and optical transmission system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000031902A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6421490B1 (en) | 1998-02-23 | 2002-07-16 | Corning Incorporated | Low slope dispersion managed waveguide |
| US6594428B1 (en) | 1999-03-09 | 2003-07-15 | Kdd Corporation | Dispersion compensating optical transmission line and system |
| US6754420B2 (en) | 2001-01-31 | 2004-06-22 | Kddi Submarine Cable Systems Inc. | Optical fiber transmission line |
| US6768872B1 (en) | 1999-09-24 | 2004-07-27 | Kdd Corporation | Optical transmission system, optical transmission line and optical transmitter |
-
1998
- 1998-07-09 JP JP10194379A patent/JP2000031902A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6421490B1 (en) | 1998-02-23 | 2002-07-16 | Corning Incorporated | Low slope dispersion managed waveguide |
| US6829423B2 (en) | 1998-02-23 | 2004-12-07 | Corning Incorporated | Low slope dispersion managed waveguide |
| US6594428B1 (en) | 1999-03-09 | 2003-07-15 | Kdd Corporation | Dispersion compensating optical transmission line and system |
| US6768872B1 (en) | 1999-09-24 | 2004-07-27 | Kdd Corporation | Optical transmission system, optical transmission line and optical transmitter |
| US6754420B2 (en) | 2001-01-31 | 2004-06-22 | Kddi Submarine Cable Systems Inc. | Optical fiber transmission line |
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