JPH06104868A - Wavelength multiplexed optical relay transmission system - Google Patents
Wavelength multiplexed optical relay transmission systemInfo
- Publication number
- JPH06104868A JPH06104868A JP4253299A JP25329992A JPH06104868A JP H06104868 A JPH06104868 A JP H06104868A JP 4253299 A JP4253299 A JP 4253299A JP 25329992 A JP25329992 A JP 25329992A JP H06104868 A JPH06104868 A JP H06104868A
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- Prior art keywords
- optical
- wavelength
- optical fiber
- fiber transmission
- repeater
- Prior art date
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、複数波の光信号を中継
伝送する波長多重光中継伝送システムに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wavelength division multiplexing optical repeater transmission system for repeating and transmitting optical signals of a plurality of waves.
【０００２】[0002]
【従来の技術】図４は、従来の波長多重光中継伝送シス
テムの構成を示す構成図である。この図に示されたシス
テムは、多重数ｎの一方向伝送システムである。図にお
いて、１１０、２１０は１本の光ファイバ伝送路３１で
結ばれる送信端局、受信端局であり、光ファイバ伝送路
３１上には波長多重された光信号を一括して増幅する一
括光増幅器７が中継器として設けられている。2. Description of the Related Art FIG. 4 is a configuration diagram showing a configuration of a conventional wavelength division multiplexing optical repeater transmission system. The system shown in this figure is a one-way transmission system with multiplex number n. In the figure, reference numerals 110 and 210 denote a transmitting terminal station and a receiving terminal station connected by one optical fiber transmission line 31, and a collective light for collectively amplifying wavelength-multiplexed optical signals on the optical fiber transmission line 31. The amplifier 7 is provided as a repeater.
【０００３】送信端局１１０において、ｎ本の情報信号
は、それぞれ各光送信器１1 〜１nで波長λ1 〜λn の
光信号に変換される。ｎ波の光信号は、光合波器５で波
長多重され、光ファイバ伝送路３１に送出される。送出
された光信号は、光ファイバ伝送路３１における損失の
補償のために一括光増幅器７で一括増幅されつつ、受信
端局２１０に伝送される。[0003] In the transmitting end station 110, n the information signal is converted into an optical signal of wavelength lambda 1 to [lambda] n in the optical transmitter 1 1 to 1 n, respectively. The n-wave optical signal is wavelength-multiplexed by the optical multiplexer 5 and sent to the optical fiber transmission line 31. The transmitted optical signal is transmitted to the receiving terminal station 210 while being collectively amplified by the collective optical amplifier 7 for compensating for the loss in the optical fiber transmission line 31.
【０００４】受信端局２１０において、光分波器６は、
１本の光ファイバ伝送路３１で伝送された波長多重され
た光信号を波長λ1 〜λn の光信号に分け、それぞれを
対応する光受信器２1 〜２n に供給する。各光受信器２
1 〜２n は、各光信号に応じた情報信号を出力する。In the receiving terminal station 210, the optical demultiplexer 6 is
Divided one optical signal transmitted wavelength multiplexed optical fiber transmission path 31 to an optical signal of wavelength lambda 1 to [lambda] n, the corresponding supply to the optical receiver 2 1 to 2 n, respectively. Each optical receiver 2
1 to 2 n output an information signal corresponding to each optical signal.
【０００５】ところで、一般に、１本の光ファイバ中を
複数の異なる波長の光信号が伝搬する場合、光ファイバ
の材質の非線形応答によってそれらの光信号の和周波数
および差周波数に相当する波長の新たな光波が発生す
る。この現象は４光波混合として知られている。その新
たな光波がもともとの光信号の波長と一致すると漏話を
生じることになり、光信号のＳＮ比が劣化する。すなわ
ち、伝送品質が悪化する。このことは、文献（”LIMITA
TIONS OF WDM TRANSMISSION OVER 560Km DUE TODEGENER
ATE FOUR WAVE MIXING ", Electronics Letters, 第28
巻第 3号, 1992,p.307 - p.309 ）にも報告されてい
る。By the way, in general, when a plurality of optical signals of different wavelengths propagate in one optical fiber, the wavelengths corresponding to the sum frequency and the difference frequency of those optical signals are changed due to the nonlinear response of the material of the optical fiber. A large light wave is generated. This phenomenon is known as four-wave mixing. When the new light wave matches the original wavelength of the optical signal, crosstalk occurs, and the SN ratio of the optical signal deteriorates. That is, the transmission quality deteriorates. This can be found in the literature ("LIMITA
TIONS OF WDM TRANSMISSION OVER 560Km DUE TODEGENER
ATE FOUR WAVE MIXING ", Electronics Letters, No. 28
Vol. 3, 1992, p.307-p.309).
【０００６】[0006]
【発明が解決しようとする課題】従来の波長多重光中継
伝送システムは以上のように構成されているので、波長
多重信号を１本の光ファイバ伝送路３１で長距離にわた
って伝送すると４光波混合によって伝送品質が悪化する
という課題があった。Since the conventional wavelength-multiplexed optical repeater transmission system is constructed as described above, when a wavelength-multiplexed signal is transmitted over a long distance through one optical fiber transmission line 31, four-wave mixing is performed. There was a problem that the transmission quality deteriorates.
【０００７】よって、本発明の目的は、複数波長の各信
号を光ファイバ伝送路で伝送する際に伝送品質を従来の
システムにおけるそれより向上させうる波長多重光中継
伝送システムを提供することである。Therefore, an object of the present invention is to provide a wavelength division multiplexing optical repeater transmission system capable of improving the transmission quality when transmitting signals of a plurality of wavelengths through an optical fiber transmission line, compared to the conventional system. .
【０００８】[0008]
【課題を解決するための手段】本発明に係る波長多重光
中継伝送システムは、それぞれが１つの光信号または４
光波混合の影響を受けにくい波長間隔をもった複数の光
信号を伝送する複数の光ファイバ伝送路を備え、伝送路
上に設けられた中継器が、光ファイバ伝送路を伝送され
てきた各光信号を合波する光合波器と、この光合波器の
出力を一括増幅する一括光増幅器と、この一括光増幅器
の増幅出力を分波して各光ファイバ伝送路に送出する光
分波器とを有する構成である。A wavelength division multiplexing optical repeater transmission system according to the present invention has one optical signal or four optical signals, respectively.
Each optical signal transmitted through the optical fiber transmission line is a repeater equipped with a plurality of optical fiber transmission lines that transmit a plurality of optical signals having wavelength intervals that are not easily affected by light wave mixing. An optical multiplexer that multiplexes the optical multiplexer, a collective optical amplifier that collectively amplifies the output of this optical multiplexer, and an optical demultiplexer that demultiplexes the amplified output of this collective optical amplifier and sends it to each optical fiber transmission line. It is a structure having.
【０００９】[0009]
【作用】本発明における各光ファイバ伝送路は、それぞ
れ４光波混合による光波の影響を受ける程度の少ない波
長の組合せによる光信号を伝送する。伝送路上に設けら
れ各光信号を増幅する中継器は、伝送される各光信号を
一括増幅する。Each of the optical fiber transmission lines in the present invention transmits an optical signal having a combination of wavelengths which is less affected by the light waves due to the four-wave mixing. The repeater, which is provided on the transmission path and amplifies each optical signal, collectively amplifies each transmitted optical signal.
【００１０】[0010]
【実施例】図１は、本発明の第１の実施例による波長多
重光中継伝送システムの構成を示す構成図である。図に
おいて、１０１，２０１はｎ波の光信号のそれぞれに対
応したｎ本の光ファイバ伝送路３1 〜３n で結ばれる送
信端局，受信端局であり、中継器４は各光ファイバ伝送
路３1 〜３n 上の光信号を増幅する。1 is a block diagram showing the structure of a wavelength division multiplexing optical repeater transmission system according to a first embodiment of the present invention. In the figure, 101 and 201 are a transmission terminal station and a reception terminal station connected by n optical fiber transmission lines 3 1 to 3 n corresponding to n-wave optical signals, respectively, and a repeater 4 is used for each optical fiber transmission. Amplifies the optical signal on the paths 3 1 to 3 n .
【００１１】この場合には、光ファイバ伝送路３1 〜３
n は１本の光ファイバケーブル３０にまとめられる。通
常、１０〜１００本程度の光ファイバ伝送路をまとめた
１本の光ファイバケーブルとされる。なお、現在では、
１０００本以上を１本の光ファイバケーブルにまとめる
こともできる。In this case, the optical fiber transmission lines 3 1 to 3
n is integrated into one optical fiber cable 30. Usually, one optical fiber cable is formed by assembling about 10 to 100 optical fiber transmission lines. At present,
It is also possible to combine 1000 or more cables into one optical fiber cable.
【００１２】送信端局１０１において、各光送信器１1
〜１n は、波長λ1 〜λn の各光信号を対応した光ファ
イバ伝送路３1 〜３n に送出する。ｎ本の光ファイバ伝
送路３1 〜３n で伝送された各波長の光信号は、光ファ
イバ伝送路３1 〜３n における損失の補償のために中継
器４で増幅されつつ、受信端局２０１に伝送される。In the transmitting terminal station 101, each optical transmitter 1 1
To 1 n is transmitted to the optical fiber transmission line 3 1 to 3 n which corresponds to the optical signal of the wavelength lambda 1 to [lambda] n. n optical signals of each wavelength transmitted by the optical fiber transmission line 3 1 to 3 n of the book, while being amplified by the repeater 4 to compensate for losses in the optical fiber transmission line 3 1 to 3 n, the receiving terminal station 201 is transmitted.
【００１３】中継器４において、まず、ｎ波の光信号
は、光合波器５で波長多重された光信号とされる。よっ
て、一括光増幅器７によって一括増幅することが可能に
なる。増幅された波長多重光信号は、光分波器６で各波
長の光信号に分波され、光ファイバ伝送路３1 〜３n に
送出される。そのような増幅が順次中継器でなされるこ
とにより、長距離多段中継伝送しても光ファイバ中にお
ける４光波混合による新たな光波の発生を防止できる。In the repeater 4, first, the n-wave optical signal is wavelength-multiplexed by the optical multiplexer 5. Therefore, it becomes possible to carry out collective amplification by the collective optical amplifier 7. The amplified wavelength-multiplexed optical signal is demultiplexed by the optical demultiplexer 6 into optical signals of respective wavelengths and sent to the optical fiber transmission lines 3 1 to 3 n . By sequentially performing such amplification by the repeater, it is possible to prevent the generation of a new light wave due to the four-wave mixing in the optical fiber even in the long-distance multi-stage relay transmission.
【００１４】受信端局２０１において、各光受信器２1
〜２n は、ｎ本の光ファイバ伝送路３1 〜３n で伝送さ
れた波長λ1 〜λn の各光信号を受信し、各光信号に応
じた情報信号を出力する。In the receiving terminal station 201, each optical receiver 2 1
To 2 n receives the optical signals of transmission wavelength lambda 1 to [lambda] n in n optical fiber transmission path 3 1 to 3 n, and outputs an information signal corresponding to each optical signal.
【００１５】ところで、光ファイバ中を波長多重された
光信号が伝送される場合であっても、各波長が４光波混
合の影響を無視できるような関係にあれば問題はない。
例えば、４光波混合光の強度がもとの光信号の波長間隔
の２乗にほぼ反比例することを利用する。すなわち、４
光波混合の影響を無視しうるほど十分に波長間隔が離れ
た各波長については、４光波混合光の波長と光信号の波
長とが重なったとしても、波長多重した場合にもとの光
信号に与えられる４光波混合の影響は小さい。By the way, even in the case where the wavelength-multiplexed optical signal is transmitted through the optical fiber, there is no problem as long as the influences of the four-wave mixing can be ignored for each wavelength.
For example, the fact that the intensity of the four-wave mixed light is approximately inversely proportional to the square of the wavelength interval of the original optical signal is used. Ie 4
For each wavelength that is separated by a wavelength enough to ignore the effect of lightwave mixing, even if the wavelength of the four lightwave mixed light and the wavelength of the optical signal overlap, the original optical signal is obtained when wavelength-multiplexed. The influence of the four-wave mixing given is small.
【００１６】図２は、そのような見地にもとづく本発明
の第２の実施例による波長多重光中継伝送システムの構
成を示す構成図である。この場合には、送信端局１０２
の光合波器８は、各光送信器１1 〜１n が送出した波長
λ1 〜λn の各光信号のうち十分に波長間隔が離れたも
の同士を合波し、それぞれ波長多重されたｍ波（ｍ＜
ｎ）の光信号を作成する。そして、光合波器８は、ｍ波
の光信号を対応した光ファイバ伝送路３1 〜３m に送出
する。FIG. 2 is a block diagram showing the construction of a wavelength division multiplexing optical repeater transmission system according to the second embodiment of the present invention based on such a viewpoint. In this case, the transmitting terminal station 102
The optical coupler 8, with each other multiplexes sufficiently what wavelength interval apart among the optical signal of the wavelength lambda 1 to [lambda] n to the optical transmitter 1 1 to 1 n is transmitted, are respectively wavelength-multiplexed m wave (m <
n) Create an optical signal. Then, the optical multiplexer 8 sends a light signal of m waves in the optical fiber transmission line 3 1 to 3 m which corresponds.
【００１７】中継器４１において、光合波器５１は、ｍ
波の光信号を合波して波長λ1 〜λ n の各光信号が波長
多重された光信号とする。一括光増幅器７は、その波長
多重された光信号を一括増幅する。増幅された波長多重
光信号は、光分波器６１でｍ波の光信号に分波され、光
ファイバ伝送路３1 〜３m に送出される。このようにし
て、もともとの光信号が光ファイバの４光波混合の影響
を受けにくくするとともに、第１の実施例によるシステ
ムに比べて光ファイバの数が削減され、より経済的なシ
ステムが構築される。例えば、波長λ1 〜λn の各光信
号を２波ずつ合波してｍ＝ｎ／２とすれば、光ファイバ
数は第１の実施例の場合に比べて１／２となる。もちろ
ん、ｍは１／２に限らずｎより小さい任意の自然数とす
ることができる。In the repeater 41, the optical multiplexer 51 is
Wavelength λ1~ Λ nEach optical signal of wavelength
It is a multiplexed optical signal. The collective optical amplifier 7 has its wavelength
Collectively amplifies the multiplexed optical signals. Amplified wavelength division multiplexing
The optical signal is demultiplexed into an m-wave optical signal by the optical demultiplexer 61,
Fiber transmission line 31~ 3mSent to. Like this
The original optical signal is affected by the four-wave mixing of the optical fiber.
System and the system according to the first embodiment.
Reduces the number of optical fibers compared to the
The stem is built. For example, the wavelength λ1~ ΛnEach light of
If two signals are combined by m = n / 2, the optical fiber
The number is 1/2 as compared with the case of the first embodiment. Mochiro
However, m is not limited to 1/2 and can be any natural number smaller than n.
You can
【００１８】また、図２に示された構成において、波長
多重されたｍ波の各光信号中の各波長を、それらの波長
の和差周波数に応じた波長が光信号中の各波長と異なる
よう選定してもよい。その場合には４光波混合による光
波の波長ともとの光信号の波長とを異ならせることがで
き、４光波混合の影響防止に効果的である。In the configuration shown in FIG. 2, the wavelengths of the m-wavelength optical signals that are wavelength-multiplexed are different from the wavelengths of the optical signals in the wavelengths corresponding to the sum / difference frequencies of the wavelengths. May be selected. In that case, the wavelength of the light wave resulting from the four-wave mixing can be made different from the wavelength of the original optical signal, which is effective in preventing the influence of the four-wave mixing.
【００１９】図３は、各実施例において使用される光合
波器５および光分波器６の構成例を示したものである。
図に示したものは５波の合分波器の例であるが、各波長
は、波長決定部５２介して光合分波部５３で他の波長と
合波され、最終的に５波波長多重された光信号が導波路
５１に得られる。あるいは、導波路５１に導かれた５波
波長多重された光信号は、各光合分波部５３および波長
決定部５２を介して各波長λ1 〜λ5 に分波される。な
お、合分波器は、その他干渉膜フィルタ等でも構成でき
る。FIG. 3 shows a configuration example of the optical multiplexer 5 and the optical demultiplexer 6 used in each embodiment.
The one shown in the figure is an example of a 5-wave multiplexer / demultiplexer, but each wavelength is multiplexed with other wavelengths by the optical multiplexer / demultiplexer 53 via the wavelength determining unit 52, and finally the 5-wavelength multiplex is performed. The optical signal thus obtained is obtained in the waveguide 51. Alternatively, the five-wavelength wavelength-multiplexed optical signal guided to the waveguide 51 is demultiplexed into each wavelength λ 1 to λ 5 via each optical multiplexing / demultiplexing unit 53 and wavelength determining unit 52. The multiplexer / demultiplexer can also be configured with an interference film filter or the like.
【００２０】[0020]
【発明の効果】以上説明したように、本発明は、波長多
重光中継伝送システムを各光ファイバ伝送路がそれぞれ
１つの光信号または４光波混合の影響の少ない波長間隔
をもった複数の光信号を伝送する構成としたので、４光
波混合の影響を排除でき伝送品質の良好なシステムを提
供できる効果がある。また、中継器で一括光増幅するこ
とから中継器の大きさを増大させず、中継装置の大きさ
が厳しく制限される海底中継伝送システムなどに好適な
システムを提供できる。As described above, the present invention provides a wavelength division multiplexing optical repeater transmission system in which each optical fiber transmission line has a single optical signal or a plurality of optical signals with wavelength intervals less affected by four-wave mixing. Since it is configured to transmit, the effect of four-wave mixing can be eliminated and a system with good transmission quality can be provided. Further, since the optical amplification is performed collectively by the repeater, it is possible to provide a system suitable for a submarine repeater transmission system in which the size of the repeater is severely limited without increasing the size of the repeater.
【図１】本発明の第１の実施例による波長多重光中継伝
送システムの構成を示す構成図である。FIG. 1 is a configuration diagram showing a configuration of a wavelength division multiplexing optical repeater transmission system according to a first embodiment of the present invention.
【図２】本発明の第２の実施例による波長多重光中継伝
送システムの構成を示す構成図である。FIG. 2 is a configuration diagram showing a configuration of a wavelength division multiplexing optical repeater transmission system according to a second embodiment of the present invention.
【図３】合分波器の構成例を示す構成図である。FIG. 3 is a configuration diagram showing a configuration example of a multiplexer / demultiplexer.
【図４】従来の波長多重光中継伝送システムの構成を示
す構成図である。FIG. 4 is a configuration diagram showing a configuration of a conventional wavelength division multiplexing optical repeater transmission system.
１０１，１０２ 送信端局 ２０１，２０２ 受信端局 ３1 〜３n 光ファイバ伝送路 ４，４１ 中継器 ５，５１ 光合波器 ６，６１ 光分波器 ７ 一括光増幅器 ８ 光合波器 ９ 光分波器101,102 Transmitting terminal station 201,202 Receiving terminal station 3 1 to 3 n Optical fiber transmission line 4,41 Repeater 5,51 Optical multiplexer 6,61 Optical demultiplexer 7 Collective optical amplifier 8 Optical multiplexer 9 Optical demultiplexer Wave instrument
Claims (1)
る波長多重光中継伝送システムにおいて、 それぞれが１つの光信号または４光波混合の影響が少な
い波長間隔をもった複数の光信号を伝送する複数の光フ
ァイバ伝送路と、 前記各光ファイバ伝送路を伝送されてきた各光信号を合
波する光合波器、この光合波器の出力を一括増幅する一
括光増幅器、およびこの一括光増幅器の増幅出力を分波
して各光ファイバ伝送路に送出する光分波器を有する中
継器とを備えたことを特徴とする光中継伝送システム。1. A wavelength division multiplexing optical repeater transmission system for repeating transmission of a plurality of optical signals having different wavelengths, each transmitting a single optical signal or a plurality of optical signals having wavelength intervals less affected by four-wave mixing. A plurality of optical fiber transmission lines, an optical multiplexer that multiplexes the optical signals transmitted through the optical fiber transmission lines, a collective optical amplifier that collectively amplifies the output of the optical multiplexer, and a collective optical amplifier An optical repeater transmission system comprising: a repeater having an optical demultiplexer for demultiplexing an amplified output and sending the demultiplexed signal to each optical fiber transmission line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4253299A JPH06104868A (en) | 1992-09-22 | 1992-09-22 | Wavelength multiplexed optical relay transmission system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4253299A JPH06104868A (en) | 1992-09-22 | 1992-09-22 | Wavelength multiplexed optical relay transmission system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06104868A true JPH06104868A (en) | 1994-04-15 |
Family
ID=17249362
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4253299A Pending JPH06104868A (en) | 1992-09-22 | 1992-09-22 | Wavelength multiplexed optical relay transmission system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06104868A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020004674A (en) * | 2000-07-07 | 2002-01-16 | 정홍기 | 5 wave optic repeater system |
| US6449085B1 (en) | 1997-12-10 | 2002-09-10 | Nec Corporation | Optical direct amplifier and control method thereof |
| JP2008042550A (en) * | 2006-08-07 | 2008-02-21 | Nippon Telegr & Teleph Corp <Ntt> | Optical communication system |
| JP2010206701A (en) * | 2009-03-05 | 2010-09-16 | Sumitomo Electric Ind Ltd | Optical transmission system |
-
1992
- 1992-09-22 JP JP4253299A patent/JPH06104868A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6449085B1 (en) | 1997-12-10 | 2002-09-10 | Nec Corporation | Optical direct amplifier and control method thereof |
| KR20020004674A (en) * | 2000-07-07 | 2002-01-16 | 정홍기 | 5 wave optic repeater system |
| JP2008042550A (en) * | 2006-08-07 | 2008-02-21 | Nippon Telegr & Teleph Corp <Ntt> | Optical communication system |
| JP2010206701A (en) * | 2009-03-05 | 2010-09-16 | Sumitomo Electric Ind Ltd | Optical transmission system |
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