JP2001094535A - Optical transmission system - Google Patents
Optical transmission systemInfo
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- JP2001094535A JP2001094535A JP27127599A JP27127599A JP2001094535A JP 2001094535 A JP2001094535 A JP 2001094535A JP 27127599 A JP27127599 A JP 27127599A JP 27127599 A JP27127599 A JP 27127599A JP 2001094535 A JP2001094535 A JP 2001094535A
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- optical
- optical transmission
- signal light
- dispersion
- multiplexer
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、光伝送システムに
関し、より具体的には、長距離・大容量伝送を可能にす
る光伝送システムに関する。[0001] 1. Field of the Invention [0002] The present invention relates to an optical transmission system, and more particularly, to an optical transmission system that enables long-distance and large-capacity transmission.
【０００２】[0002]
【従来の技術】従来の光伝送システムは、受信端局で高
いＳ／Ｎ比を得るために、光増幅中継器の出力パワーを
上げている。その結果、非線形効果が増大する。そこ
で、非線形効果を低減するために、送信側で信号光を予
め位相変調する。2. Description of the Related Art In a conventional optical transmission system, the output power of an optical amplification repeater is increased in order to obtain a high S / N ratio at a receiving terminal. As a result, non-linear effects increase. Therefore, in order to reduce the nonlinear effect, the signal light is phase-modulated in advance on the transmission side.
【０００３】[0003]
【発明が解決しようとする課題】しかし、位相変調は信
号光のスペクトル線幅を拡げる方向に作用する。従っ
て、波長分割多重伝送システムでは、波長間隔を狭くす
るのを困難にする。光伝送路の信号波長帯域は、一般的
に、光中継増幅器の増幅帯域により制限されるので、波
長多重度を上げるには、波長間隔を狭くするしかない。However, phase modulation acts in the direction of expanding the spectral line width of signal light. Therefore, in the wavelength division multiplex transmission system, it is difficult to narrow the wavelength interval. Since the signal wavelength band of the optical transmission line is generally limited by the amplification band of the optical repeater amplifier, the only way to increase the wavelength multiplexing is to narrow the wavelength interval.
【０００４】本発明は、高い信頼性の下で、より高密度
のＷＤＭ伝送を実現する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 system that realizes higher-density WDM transmission with high reliability.
【０００５】[0005]
【課題を解決するための手段】本発明に係る光伝送シス
テムは、複数の光増幅中継スパンを具備する光伝送路
と、隣接波長チャネルの信号光を互いに直交する偏波で
当該光伝送路に出力する光送信装置と、当該光伝送路を
伝送した当該信号光を受信する光受信装置とからなる光
伝送システムであって、当該光増幅中継スパンが、信号
光を光増幅する光増幅中継器と、第１の実効断面積及び
第１の分散スロープを具備し、当該光増幅中継器の出力
に接続する第１の光ファイバと、当該第１の光ファイバ
に接続し、当該第１の実効断面積より小さい第２の実効
断面積及び当該第１の分散スロープより小さい第２の分
散スロープを具備し、当該第１の光ファイバよりも長い
第２の光ファイバとからなることを特徴とする。An optical transmission system according to the present invention comprises: an optical transmission line having a plurality of optical amplification repeater spans; and a signal light of an adjacent wavelength channel is transmitted to the optical transmission line with polarizations orthogonal to each other. An optical transmission system, comprising: an optical transmission device for outputting an optical signal; and an optical reception device for receiving the signal light transmitted through the optical transmission line, wherein the optical amplification repeater span optically amplifies the signal light. A first optical fiber having a first effective area and a first dispersion slope, and connected to the output of the optical amplification repeater; and a first optical fiber connected to the first optical fiber, A second optical fiber having a second effective cross-sectional area smaller than the cross-sectional area and a second dispersion slope smaller than the first dispersion slope, and being longer than the first optical fiber. .
【０００６】隣接波長チャネルを直交偏波で合波するこ
とで、隣接チャネル間の干渉を低減する。これにより、
チャネル間隔を狭くすることができる。光増幅中継スパ
ン内で、光増幅中継器の出力に、相対的に実効断面積の
大きな第１の光ファイバを接続することで、非線形作用
を低減する。第１の光ファイバの後に、実効断面積は小
さくなるものの、分散スロープの小さいな第２の光ファ
イバを配置することで、光増幅中継スパン内、ひいては
伝送路全体の平均分散スロープを低減する。これによ
り、チャネル間の累積波長分散の差を小さくすることが
でき、分散スロープの補償を考える必要無しに、長距離
伝送を実現できる。[0006] By multiplexing adjacent wavelength channels with orthogonal polarization, interference between adjacent channels is reduced. This allows
Channel spacing can be reduced. By connecting the first optical fiber having a relatively large effective area to the output of the optical amplification repeater within the optical amplification repeater span, the nonlinear effect is reduced. By arranging the second optical fiber having a small effective slope but a small effective slope after the first optical fiber, the average dispersion slope in the optical amplification repeater span and, consequently, the entire transmission line is reduced. As a result, the difference in the accumulated chromatic dispersion between channels can be reduced, and long-distance transmission can be realized without having to consider dispersion slope compensation.
【０００７】好ましくは、光伝送路が更に、所定間隔に
配置され、信号光の累積波長分散を補償する分散補償手
段を具備する。これにより、累積波長分散を所定値範囲
内に抑制でき、長距離の伝送が可能になる。Preferably, the optical transmission line is further provided with a dispersion compensating means arranged at a predetermined interval and compensating for the accumulated chromatic dispersion of the signal light. As a result, the accumulated chromatic dispersion can be suppressed within a predetermined value range, and long-distance transmission becomes possible.
【０００８】好ましくは、光伝送路が更に、所定間隔に
配置され、各信号光の利得を平坦化する利得等化手段を
具備する。これにより、チャネル間の伝送特性の変動を
抑圧できる。Preferably, the optical transmission line is further provided with a gain equalizing means arranged at a predetermined interval and for flattening the gain of each signal light. This makes it possible to suppress fluctuations in transmission characteristics between channels.
【０００９】好ましくは、光送信装置が、奇数波長チャ
ネルの信号光を合波する第１の合波器と、偶数波長チャ
ネルの信号光を合波する第２の合波器と、当該第１の合
波器の出力光と、当該第２の合波器の出力光を互いに直
交する偏波で合波する偏光合波器とを具備する。この構
成により、多数の信号光があっても、１つの偏光合波器
で済む。Preferably, the optical transmitting apparatus includes a first multiplexer that multiplexes the signal light of the odd wavelength channel, a second multiplexer that multiplexes the signal light of the even wavelength channel, and the first multiplexer. And a polarization multiplexer for multiplexing the output light of the second multiplexer with polarizations orthogonal to each other. With this configuration, even if there are many signal lights, only one polarization multiplexer is required.
【００１０】好ましくは、当該光増幅中継スパンの平均
分散スロープが約０．０７ｐｓ／ｎｍ２／ｋｍ以下であ
る。このように分散スロープを小さくすることで、チャ
ネル間の累積波長分散の差を小さくでき、長距離伝送を
実現しやすくなる。[0010] Preferably, the average dispersion slope of the optical amplification repeater span is about 0.07 ps / nm 2 / km or less. By reducing the dispersion slope in this way, the difference in accumulated chromatic dispersion between channels can be reduced, and long-distance transmission can be easily realized.
【００１１】[0011]
【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.
【００１２】図１は、本発明の一実施例の概略構成ブロ
ック図を示す。１０はそれぞれ異なる１００波長λ１〜
λ１００の信号光を波長多重して出力する光送信装置、
１２は、光ファイバ伝送路、１４は光ファイバ伝送路１
２を伝送した波長多重信号光を受信する光受信装置であ
る。FIG. 1 is a schematic block diagram showing the configuration of an embodiment of the present invention. 10 are 100 wavelengths λ 1 different from each other.
an optical transmitter that wavelength-multiplexes and outputs the signal light of λ 100 ,
12 is an optical fiber transmission line, 14 is an optical fiber transmission line 1
2 is an optical receiving device that receives the wavelength multiplexed signal light that has transmitted No. 2.
【００１３】光送信装置１０は、以下のような構成から
なる。即ち、信号光発生装置２０ａは、奇数波長（又は
奇数チャネル）λ１，λ３，・・・，λ９９の信号光を
発生し、信号光発生装置２０ｂは、偶数波長（又は偶数
チャネル）λ２，λ４，・・・，λ１００の信号光を発
生する。信号光発生装置２０ａ，２０ｂはそれぞれ、実
際には、各波長でレーザＣＷ発振する５０個のレーザダ
イオードと、各レーザダイオードの出力光を送信すべき
データで強度変調、例えば、ＲＺ変調する５０個の強度
変調器からなる。従来は、非線形作用低減のために位相
変調器を強度変調器の後段に配置したが、本実施例で
は、位相変調器を使用しない。位相変調によるスペクト
ラム拡がりを避けるためである。The optical transmission device 10 has the following configuration. That is, the signal light generator 20a generates signal light of odd wavelengths (or odd channels) λ 1 , λ 3 ,..., Λ 99 , and the signal light generator 20b generates even wavelengths (or even channels) λ. 2, λ 4, ···, to generate a signal light of λ 100. Each of the signal light generators 20a and 20b is, in fact, 50 laser diodes that oscillate laser CW at each wavelength and 50 laser diodes that perform intensity modulation, for example, RZ modulation with data to transmit output light of each laser diode. Of the intensity modulator. Conventionally, a phase modulator is disposed after an intensity modulator to reduce nonlinear effects. However, in this embodiment, a phase modulator is not used. This is to avoid spectrum spread due to phase modulation.
【００１４】各波長λ１〜λ１００の信号光は、１０Ｇ
ｂｉｔｓ／ｓである。従って、全体として、１Ｔｂｉｔ
ｓ／ｓとなる。The signal light of each wavelength λ 1 to λ 100 is 10 G
bits / s. Therefore, as a whole, 1 Tbit
s / s.
【００１５】分散等化器２２ａは、信号光発生装置２０
ａの出力する各奇数波長λ１〜λ９ ９の信号光にそれぞ
れ予め所定の波長分散を与える５０個の分散等化素子か
らなり、同様に、分散等化器２２ｂは、信号光発生装置
２０ｂの出力する各偶数波長λ２〜λ１００の信号光に
それぞれ予め所定の波長分散を与える５０個の分散等化
素子からなる。隣接する複数の波長の信号光を合波し
て、１つの分散等化素子に導くようにして、複数の波長
に一括して、各波長に対応する所定の波長分散を与える
ようにしてもよい。The dispersion equalizer 22a is connected to the signal light generator 20.
consists 50 dispersion equalization device providing a respective pre-specified wavelength dispersion in the signal light of each odd wavelengths lambda 1 to [lambda] 9 9 outputs of a, likewise, dispersion equalizer 22b, the signal light generator 20b And 50 dispersion equalizing elements for giving predetermined chromatic dispersion to the signal light of each of the even wavelengths λ 2 to λ 100 output in advance. A plurality of signal lights having a plurality of adjacent wavelengths may be multiplexed and guided to one dispersion equalizing element, so that a predetermined chromatic dispersion corresponding to each wavelength may be given to a plurality of wavelengths. .
【００１６】合波器２４ａ，２４ｂはそれぞれ、分散等
化器２２ａ，２２ｂの出力光を合波、すなわち、波長多
重する。偏光ビーム・スプリッタ２６は、合波器２４
ａ，２４ｂの出力光を、互いに直交する偏波で合波す
る。偏波合波されたλ１〜λ１０ ０の信号光は光ファイ
バ伝送路１２に出力される。偏光ビーム・スプリッタ２
６に奇数チャネルの信号光と偶数チャネルの信号光を互
いに直交した状態で入力するために、信号発生装置２０
ａから偏光ビーム・スプリッタ２６まで、及び、信号発
生装置２０ｂから偏光ビーム・スプリッタ２６までを、
偏波保持系にしてある。信号発生装置２０ａ，２０ｂと
合波器２４ａ，２４ｂの間に、各信号光を所望の偏波に
制御する偏波制御装置を配置するのが好ましい。The multiplexers 24a and 24b multiplex, ie, multiplex, the output lights of the dispersion equalizers 22a and 22b. The polarization beam splitter 26 is
The output lights a and 24b are multiplexed with polarizations orthogonal to each other. Signal light lambda 1 to [lambda] 10 0 which are polarization multiplexed is output to the optical fiber transmission line 12. Polarized beam splitter 2
In order to input the odd-numbered channel signal light and the even-numbered channel signal light orthogonally to each other, the signal generator 20
a to the polarizing beam splitter 26, and from the signal generator 20b to the polarizing beam splitter 26,
It is a polarization maintaining system. It is preferable to arrange a polarization controller for controlling each signal light to a desired polarization between the signal generators 20a and 20b and the multiplexers 24a and 24b.
【００１７】光ファイバ伝送路１２は、次のような構成
からなる。光増幅中継器３０として、ノイズ指数の小さ
い０．９８μｍ励起のエルビウム添加光増幅ファイバを
使用した。非線形効果を低減するために、光増幅中継器
３０の出力を従来よりも下げ、１２ｄＢｍとした。光増
幅中継器３０の出力パワーの低下による受信信号のＳ／
Ｎ比の低下を、低ノイズの光増幅中継器を使用すること
でカバーした。The optical fiber transmission line 12 has the following configuration. As the optical amplification repeater 30, an erbium-doped optical amplification fiber pumped with 0.98 μm and having a small noise index was used. In order to reduce the non-linear effect, the output of the optical amplification repeater 30 was reduced to 12 dBm as compared with the conventional one. S / S of the received signal due to a decrease in output power of the optical amplification repeater 30
The decrease in N ratio was covered by using a low-noise optical amplifier repeater.
【００１８】光増幅中継器３０による中継スパン内の前
半に、有効断面積の大きい（７５μｍ２）単一モード光
ファイバ３２を配置し、後半には、信号波長帯で波長分
散が非ゼロの分散シフトファイバ３４を配置する。より
具体的には、単一モード光ファイバ３２は、波長分散−
２ｐｓ／ｎｍ／ｋｍ、分散スロープ０．１０ｐｓ／ｎｍ
２／ｋｍ、長さ１０ｋｍであり、分散シフトファイバ３
４は、有効断面積５５μｍ２、波長分散−２ｐｓ／ｎｍ
／ｋｍ、分散スロープ０．０６ｐｓ／ｎｍ２／ｋｍ、長
さ３０ｋｍである。中継スパンでの平均的な分散スロー
プは、約０．０７ｐｓ／ｎｍ２／ｋｍであり、システム
全体の平均分散スロープも、約０．０７ｐｓ／ｎｍ２／
ｋｍである。A single mode optical fiber 32 having a large effective area (75 μm 2 ) is arranged in the first half of the relay span by the optical amplifying repeater 30, and in the latter half, dispersion having non-zero chromatic dispersion in the signal wavelength band. The shift fiber 34 is arranged. More specifically, the single mode optical fiber 32 has a chromatic dispersion-
2ps / nm / km, dispersion slope 0.10ps / nm
2 / km, length 10 km, dispersion-shifted fiber 3
4 is an effective area of 55 μm 2 , chromatic dispersion of −2 ps / nm
/ Km, dispersion slope 0.06 ps / nm 2 / km, and length 30 km. Average dispersion slope at the relay span is about 0.07ps / nm 2 / km, an average dispersion slope of the whole system is also approximately 0.07 ps / nm 2 /
km.
【００１９】信号光は伝搬に伴い、波長分散が累積す
る。そこで、適当な間隔で、例えば、９中継スパン当た
りに１つの割合で、累積波長分散をゼロにする分散補償
ファイバ３６を配置してある。システムの平均波長分散
がゼロになる波長は、１５５０ｎｍである。As the signal light propagates, chromatic dispersion accumulates. Therefore, at an appropriate interval, for example, at a rate of one for every nine relay spans, a dispersion compensating fiber 36 for reducing the accumulated chromatic dispersion to zero is arranged. The wavelength at which the average chromatic dispersion of the system is zero is 1550 nm.
【００２０】また、各波長の利得を平坦化するために、
適当な間隔、具体的には２００ｋｍおきに、利得等化器
３８を配置した。In order to flatten the gain of each wavelength,
The gain equalizer 38 is arranged at an appropriate interval, specifically, every 200 km.
【００２１】分散スロープ（波長による波長分散の差）
がゼロでない場合、ＷＤＭ伝送では、両端のチャネル間
で累積波長分散に差が生じる。そこで、本実施例では、
極力、分散スロープの小さいファイバ、例えば、ファイ
バ３２を使用する。しかし、分散スロープの小さいファ
イバは有効断面積を大きくしにくく、そのままでは非線
形効果が大きくなってしまうので、信号光パワーの大き
な、光増幅中継器３０の出力直後には、分散スロープは
多少大きいが、有効断面積の大きなファイバ３２を使用
する。このような配分をすることで、非線形効果を低減
しつつ、分散スロープの影響、すなわち、チャネル間の
累積波長分散の差を小さく抑制できる。分散スロープを
補償するファイバを適宜に挿入しても良いが、それで
は、光伝送路１２の構成が複雑になり、素子数の増加に
より信頼性が低下する。換言すると、本実施例は、分散
スロープ補償無しで、長距離・大容量の実現を目指して
いる。Dispersion slope (difference in chromatic dispersion according to wavelength)
Is not zero, in WDM transmission, a difference occurs in the accumulated chromatic dispersion between the channels at both ends. Therefore, in this embodiment,
A fiber with a small dispersion slope, for example, the fiber 32 is used as much as possible. However, a fiber having a small dispersion slope is difficult to increase the effective area, and the nonlinear effect becomes large as it is. , A fiber 32 having a large effective area is used. By performing such distribution, it is possible to reduce the influence of the dispersion slope, that is, the difference in the accumulated chromatic dispersion between channels, while reducing the nonlinear effect. Although a fiber for compensating for the dispersion slope may be appropriately inserted, the configuration of the optical transmission line 12 becomes complicated, and the reliability decreases due to an increase in the number of elements. In other words, this embodiment aims at realizing long distance and large capacity without dispersion slope compensation.
【００２２】光受信装置１４では、分波器４０は光伝送
路１２からのＷＤＭ信号光を各波長λ１〜λ１００に分
離する。分散等化器４２は、分波器４０からの各波長λ
１〜λ１００の信号光の累積波長分散を等化する。送信
の場合と同様に、分散等化器４２は、複数の波長の信号
光の累積波長分散を１つの等化素子で一括して等化し、
その後、各波長に分離しても良い。光受信器４４は、分
散等化器４２からの各波長λ１〜λ１００の信号光を電
気信号に変換し、搬送されたデータを復元する。In the optical receiver 14, the splitter 40 separates the WDM signal light from the optical transmission line 12 into wavelengths λ 1 to λ 100 . The dispersion equalizer 42 receives the respective wavelengths λ from the duplexer 40.
To equalize the accumulated chromatic dispersion of the signal light 1 to [lambda] 100. As in the case of the transmission, the dispersion equalizer 42 collectively equalizes the accumulated chromatic dispersion of the signal lights of a plurality of wavelengths with one equalizing element,
After that, it may be separated into each wavelength. The optical receiver 44 converts the signal light of each of the wavelengths λ 1 to λ 100 from the dispersion equalizer 42 into an electric signal, and restores the carried data.
【００２３】本実施例では、７３５８ｋｍ伝送後、チャ
ネル＃１の累積波長分散は−５０５８ｐｓ／ｎｍであ
り、チャネル＃１００の累積波長分散は４７０３ｐｓ／
ｎｍであった。また、最も伝送特性の悪いチャネルで、
ビット誤り率（ＢＥＲ）は３．９×１０−４であった。
ＦＥＣ（Ｆｏｒｗａｒｄ Ｅｒｒｏｒ ｃｏｒｒｅｃｔ
ｉｎｇ Ｃｏｄｅ）技術を使用すれば、３．９×１０
−４ＢＥＲは、８×１０− １０ＢＥＲまで改善できる。
８×１０−１０ＢＥＲに対応するＱ値は１５．６ｄＢで
ある。本実施例での平均ＢＥＲは２．０×１０−４であ
り、これはＦＥＣを適用した場合に、２．４×１０
−１２になり、Ｑ値にして１６．８ｄＢになる。従っ
て、十分に実用に耐え得るものである。In this embodiment, after transmission of 7358 km, the accumulated chromatic dispersion of channel # 1 is -5058 ps / nm, and the accumulated chromatic dispersion of channel # 100 is 4703 ps / nm.
nm. Also, the channel with the worst transmission characteristics,
The bit error rate (BER) was 3.9 × 10 −4 .
FEC (Forward Error Correct)
ing code), 3.9 × 10
-4 BER is, 8 × 10 - can be improved up to 10 BER.
The Q value corresponding to 8 × 10 −10 BER is 15.6 dB. The average BER in this embodiment is 2.0 × 10 −4 , which is 2.4 × 10 4 when FEC is applied.
−12 , which is 16.8 dB in Q value. Therefore, it can sufficiently withstand practical use.
【００２４】[0024]
【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、非線形効果が低減するように、光
増幅中継器の出力直後には、有効断面積の大きな光ファ
イバを配置し、その後で、分散スロープの小さいな分散
シフトファイバを配置することで、非線形効果を抑制す
ると共に平均的な分散スロープを小さくすることを可能
にした。これにより、ＷＤＭ信号のチャネル間の伝送特
性差を少なくし、より長い距離の伝送を可能にした。具
体的には、１０Ｇｂｉｔｓ／ｓの１００波長を波長多重
して、７０００ｋｍ以上を伝送させることを可能にし
た。As can be easily understood from the above description, according to the present invention, an optical fiber having a large effective area is disposed immediately after the output of the optical amplifying repeater so that the nonlinear effect is reduced. Then, by disposing a dispersion-shifted fiber having a small dispersion slope, it was possible to suppress the nonlinear effect and to reduce the average dispersion slope. As a result, the transmission characteristic difference between channels of the WDM signal is reduced, and transmission over a longer distance is enabled. Specifically, it is possible to multiplex 100 wavelengths of 10 Gbits / s to transmit 7000 km or more.
【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.
１０：光送信装置 １２：光ファイバ伝送路 １４：光受信装置 ２０ａ，２０ｂ：信号光発生装置 ２２ａ，２２ｂ：分散等化器 ２４ａ，２４ｂ：合波器 ２６：偏光ビーム・スプリッ ３０：光増幅中継器 ３２：単一モード光ファイバ ３４：分散シフトファイバ ３６：分散補償ファイバ ３８：利得等化器 ４０：分波器 ４２：分散等化器 ４４：光受信器 10: Optical transmitter 12: Optical fiber transmission line 14: Optical receiver 20a, 20b: Signal light generator 22a, 22b: Dispersion equalizer 24a, 24b: Combiner 26: Polarized beam split 30: Optical amplification relay 32: single mode optical fiber 34: dispersion shift fiber 36: dispersion compensating fiber 38: gain equalizer 40: duplexer 42: dispersion equalizer 44: optical receiver
───────────────────────────────────────────────────── フロントページの続き (72)発明者 後藤 光司 東京都新宿区西新宿２丁目３番２号ケイデ ィディ海底ケーブルシステム株式会社内 Ｆターム(参考） 5K002 AA01 AA03 AA06 BA05 CA01 CA10 CA13 DA02 FA01 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Goto 2-3-2 Nishishinjuku, Shinjuku-ku, Tokyo Keididi Submarine Cable System Co., Ltd. F term (reference) 5K002 AA01 AA03 AA06 BA05 CA01 CA10 CA13 DA02 FA01
Claims (5)
送路と、隣接波長チャネルの信号光を互いに直交する偏
波で当該光伝送路に出力する光送信装置と、当該光伝送
路を伝送した当該信号光を受信する光受信装置とからな
る光伝送システムであって、当該光増幅中継スパンが、 信号光を光増幅する光増幅中継器と、 第１の実効断面積及び第１の分散スロープを具備し、当
該光増幅中継器の出力に接続する第１の光ファイバと、 当該第１の光ファイバに接続し、当該第１の実効断面積
より小さい第２の実効断面積及び当該第１の分散スロー
プより小さい第２の分散スロープを具備し、当該第１の
光ファイバよりも長い第２の光ファイバとからなること
を特徴とする光伝送システム。1. An optical transmission line having a plurality of optical amplification repeater spans, an optical transmission device for outputting signal light of adjacent wavelength channels to the optical transmission line with polarizations orthogonal to each other, and transmitting the optical transmission line. An optical transmission system comprising: an optical receiver that receives the signal light; and an optical amplifier repeater that optically amplifies the signal light; a first effective area and a first dispersion. A first optical fiber having a slope and connected to the output of the optical amplification repeater; a second optical area connected to the first optical fiber and smaller than the first effective area; An optical transmission system comprising a second dispersion slope smaller than the first dispersion slope and a second optical fiber longer than the first optical fiber.
れ、信号光の累積波長分散を補償する分散補償手段を具
備する請求項１に記載の光伝送システム。2. The optical transmission system according to claim 1, wherein said optical transmission line further comprises a dispersion compensating means arranged at a predetermined interval to compensate for the accumulated chromatic dispersion of the signal light.
れ、各信号光の利得を平坦化する利得等化手段を具備す
る請求項１に記載の光伝送システム。3. The optical transmission system according to claim 1, wherein said optical transmission line further comprises a gain equalizing means arranged at a predetermined interval to flatten the gain of each signal light.
信号光を合波する第１の合波器と、偶数波長チャネルの
信号光を合波する第２の合波器と、当該第１の合波器の
出力光と、当該第２の合波器の出力光を互いに直交する
偏波で合波する偏光合波器とを具備する請求項１に記載
の光伝送システム。4. An optical transmission device comprising: a first multiplexer for multiplexing signal light of an odd wavelength channel; a second multiplexer for multiplexing signal light of an even wavelength channel; 2. The optical transmission system according to claim 1, further comprising: an output light from the multiplexer, and a polarization multiplexer that multiplexes the output light from the second multiplexer with polarizations orthogonal to each other.
プが約０．０７ｐｓ／ｎｍ２／ｋｍ以下である請求項１
に記載の光伝送システム。5. The optical amplification repeater span according to claim 1, wherein the average dispersion slope is about 0.07 ps / nm 2 / km or less.
An optical transmission system according to item 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27127599A JP2001094535A (en) | 1999-09-24 | 1999-09-24 | Optical transmission system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27127599A JP2001094535A (en) | 1999-09-24 | 1999-09-24 | Optical transmission system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2001094535A true JP2001094535A (en) | 2001-04-06 |
Family
ID=17497820
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27127599A Withdrawn JP2001094535A (en) | 1999-09-24 | 1999-09-24 | Optical transmission system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2001094535A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2384930A (en) * | 2002-01-16 | 2003-08-06 | Nec Corp | Orthogonal polarization multiplexing |
| KR100421136B1 (en) * | 2002-03-19 | 2004-03-04 | 삼성전자주식회사 | Wide band erbium doped fiber amplifier and wavelength division multiplexing transmission system therewith |
| WO2008065784A1 (en) * | 2006-11-30 | 2008-06-05 | Nec Corporation | Dispersion determining apparatus and automatic dispersion compensating system using the same |
| JP2008211493A (en) * | 2007-02-26 | 2008-09-11 | Mitsubishi Electric Corp | Distributed pre-equalization optical communication system |
-
1999
- 1999-09-24 JP JP27127599A patent/JP2001094535A/en not_active Withdrawn
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2384930A (en) * | 2002-01-16 | 2003-08-06 | Nec Corp | Orthogonal polarization multiplexing |
| GB2384930B (en) * | 2002-01-16 | 2004-04-14 | Nec Corp | Orthogonal polarization multiplexing transmission apparatus and multiplexing method used for the same |
| US7366209B2 (en) | 2002-01-16 | 2008-04-29 | Nec Corporation | Orthogonal polarization multiplexing transmission apparatus and multiplexing method used for the same |
| KR100421136B1 (en) * | 2002-03-19 | 2004-03-04 | 삼성전자주식회사 | Wide band erbium doped fiber amplifier and wavelength division multiplexing transmission system therewith |
| WO2008065784A1 (en) * | 2006-11-30 | 2008-06-05 | Nec Corporation | Dispersion determining apparatus and automatic dispersion compensating system using the same |
| JPWO2008065784A1 (en) * | 2006-11-30 | 2010-03-04 | 日本電気株式会社 | Dispersion detection device and automatic dispersion compensation system using the same |
| JP5012811B2 (en) * | 2006-11-30 | 2012-08-29 | 日本電気株式会社 | Dispersion detection device and automatic dispersion compensation system using the same |
| US8488961B2 (en) | 2006-11-30 | 2013-07-16 | Nec Corporation | Dispersion determining apparatus and automatic dispersion compensating system using the same |
| JP2008211493A (en) * | 2007-02-26 | 2008-09-11 | Mitsubishi Electric Corp | Distributed pre-equalization optical communication system |
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