JP3039430B2 - Optical add / drop circuit and optical transmission method - Google Patents

Optical add / drop circuit and optical transmission method

Info

Publication number
JP3039430B2
JP3039430B2 JP9076753A JP7675397A JP3039430B2 JP 3039430 B2 JP3039430 B2 JP 3039430B2 JP 9076753 A JP9076753 A JP 9076753A JP 7675397 A JP7675397 A JP 7675397A JP 3039430 B2 JP3039430 B2 JP 3039430B2
Authority
JP
Japan
Prior art keywords
signal light
wavelength
optical
light
station
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.)
Expired - Lifetime
Application number
JP9076753A
Other languages
Japanese (ja)
Other versions
JPH10276129A (en
Inventor
祥平 山口
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to JP9076753A priority Critical patent/JP3039430B2/en
Priority to FR9803821A priority patent/FR2761484A1/en
Publication of JPH10276129A publication Critical patent/JPH10276129A/en
Application granted granted Critical
Publication of JP3039430B2 publication Critical patent/JP3039430B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J14/00Optical multiplex systems
    • H04J14/02Wavelength-division multiplex systems
    • H04J14/0201Add-and-drop multiplexing
    • H04J14/0202Arrangements therefor
    • H04J14/0204Broadcast and select arrangements, e.g. with an optical splitter at the input before adding or dropping
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J14/00Optical multiplex systems
    • H04J14/02Wavelength-division multiplex systems
    • H04J14/0201Add-and-drop multiplexing
    • H04J14/0202Arrangements therefor
    • H04J14/0213Groups of channels or wave bands arrangements
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24Coupling light guides
    • G02B6/26Optical coupling means
    • G02B6/28Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29304Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
    • G02B6/29316Light guides comprising a diffractive element, e.g. grating in or on the light guide such that diffracted light is confined in the light guide
    • G02B6/29317Light guides of the optical fibre type
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24Coupling light guides
    • G02B6/26Optical coupling means
    • G02B6/28Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29346Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by wave or beam interference
    • G02B6/29361Interference filters, e.g. multilayer coatings, thin film filters, dichroic splitters or mirrors based on multilayers, WDM filters
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24Coupling light guides
    • G02B6/26Optical coupling means
    • G02B6/28Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29379Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device
    • G02B6/2938Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM
    • G02B6/29382Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM including at least adding or dropping a signal, i.e. passing the majority of signals
    • G02B6/29383Adding and dropping
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J14/00Optical multiplex systems
    • H04J14/02Wavelength-division multiplex systems
    • H04J14/0201Add-and-drop multiplexing
    • H04J14/0202Arrangements therefor
    • H04J14/0205Select and combine arrangements, e.g. with an optical combiner at the output after adding or dropping

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Optical Communication System (AREA)

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、信号光を分岐、挿
入する機能を有する光分岐挿入装置を主伝送路中に備え
た波長多重光伝送装置に関し、特に、光分岐挿入装置に
おいて分岐されるけ信号光およびこれを通過する通過信
号光の追加を容易にする光伝送装置に関する。また、こ
の装置を用いた光伝送方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for splitting and inserting signal light.
Optical add / drop multiplexer having a function of inserting
Wavelength multiplexing optical transmission equipment, especially for optical add / drop multiplexers
Signal light that is branched in
The present invention relates to an optical transmission device that facilitates addition of light. Also,
And an optical transmission method using the device .

【0002】[0002]

【従来の技術】従来、光分岐挿入回路1aを用いた長距
離光伝送システムは、図9に示すような基本構成を備え
ている。すなわち、局舎6から波長多重され、送出され
た複数の波長の信号光が光分岐挿入回路1aに入力され
る。これらの信号光のうち1または数波長分の信号光は
分波器4により分岐出力として局舎8aに送出される。
局舎8aは入力信号と同じ波長の信号を光分岐挿入回路
1aへ送出する。光分岐挿入回路1aでは、合波器5が
分波器4を透過した信号光と局舎8aから入力された信
号光を合波し、局舎7へ送る。
2. Description of the Related Art Conventionally, a long-distance optical transmission system using an optical add / drop circuit 1a has a basic configuration as shown in FIG. That is, the signal light of a plurality of wavelengths that has been wavelength-multiplexed and transmitted from the station 6 is input to the optical add / drop circuit 1a. Of these signal lights, the signal light of one or several wavelengths is transmitted to the station 8a by the splitter 4 as a branch output.
The station 8a sends out a signal having the same wavelength as the input signal to the optical add / drop circuit 1a. In the optical add / drop circuit 1a, the multiplexer 5 multiplexes the signal light transmitted through the demultiplexer 4 and the signal light input from the station 8a, and sends the multiplexed signal to the station 7.

【0003】[0003]

【発明が解決しようとする課題】一般に、長距離光伝送
システムでは、システムを設置した後に、通信容量を増
やす必要が生じることがある。図9に示したシステムで
は、光分岐挿入回路1aから分岐する分岐路の信号光の
数や光分岐挿入回路1aを透過する主伝送路の信号光の
数を増加させる場合である。このような場合に、光分岐
挿入回路1aを一度システムから取り外し、ファイバグ
レーテイングや光バンドパスフィルタなどの部品を特性
の異なるものと交換しなければならない。しかし、光分
岐挿入回路1aが海底中継システムに適用されている場
合、部品または光分岐挿入回路1aの交換には多額に費
用が必要である。
Generally, in a long-distance optical transmission system, it may be necessary to increase the communication capacity after the system is installed. The system shown in FIG. 9 is a case where the number of signal lights in a branch path branched from the optical add / drop circuit 1a and the number of signal lights in a main transmission path passing through the optical drop / add circuit 1a are increased. In such a case, the optical add / drop circuit 1a must be once removed from the system, and components such as fiber gratings and optical bandpass filters must be replaced with components having different characteristics. However, when the optical add / drop circuit 1a is applied to a submarine repeater system, replacing components or the optical add / drop circuit 1a requires a large amount of cost.

【0004】本発明の目的は、光分岐挿入回路が適用さ
れた光伝送システムにおいて、光分岐挿入回路を交換し
なくても、システムの設置後に通信容量を増やすことが
できる光分岐挿入回路の構成と該回路を用いた光伝送方
法を提供することにある。
An object of the present invention is to provide a configuration of an optical add / drop circuit that can increase the communication capacity after installation of the system in an optical transmission system to which the optical add / drop circuit is applied, without replacing the optical drop / add circuit. And an optical transmission method using the circuit.

【0005】[0005]

【課題を解決するための手段】上記課題を解決する本発
明の光伝送装置は、入力光信号を第1と第2の出力光に
分波する光分波器と、第1の出力光が入力する高域透過
フィルタと、第2の出力光が入力する低域透過フィルタ
と、前記高域透過フィルタから出力される信号光と他の
入力光とを合波する合波器を備えている。この光分岐挿
入回路を用いて光伝送を行う場合、該光分岐挿入回路の
分岐側から出力する信号光を増やす場合は上記低域透過
フィルタを透過する信号光を送信局から送信し、光分岐
挿入回路を透過する信号光を増やす場合は上記高域透過
フィルタを透過する信号光を送信局から送信する。
According to the present invention, there is provided an optical transmission apparatus for splitting an input optical signal into first and second output lights, and an optical splitter for splitting an input optical signal into first and second output lights. A high-pass filter for inputting, a low-pass filter for inputting second output light, and a multiplexer for multiplexing the signal light output from the high-pass filter with other input light. . When optical transmission is performed using this optical add / drop circuit, when increasing the signal light output from the branch side of the optical add / drop circuit, the signal light transmitted through the low-pass filter is transmitted from the transmitting station, and the optical drop is performed. When increasing the signal light transmitted through the insertion circuit, the signal light transmitted through the high-pass filter is transmitted from the transmitting station.

【0006】次に、本発明の光分岐挿入回路の別の構成
では、入力する光信号を第1と第2の出力光に分波する
光分波器と、第1の出力光が入力する低域透過フィルタ
と、第2の出力光が入力する高域透過フィルタと、前記
低域透過フィルタから出力される信号光と他の入力光と
を合波する合波器を備えている。この光分岐挿入回路を
用いて光伝送を行う場合、該光分岐挿入回路の分岐側か
ら出力する信号光を増やす場合は上記高域透過フィルタ
を透過する信号光を送信局から送信し、光分岐挿入回路
の透過側への信号光を増やす場合は上記低域透過フィル
タを透過する信号光を送信局から送信する。
Next, in another configuration of the optical add / drop circuit of the present invention, an optical splitter for splitting an input optical signal into first and second output lights, and the first output light are input. A low-pass filter, a high-pass filter to which the second output light is input, and a multiplexer for multiplexing the signal light output from the low-pass filter with another input light. When optical transmission is performed using the optical add / drop circuit, when increasing the signal light output from the branch side of the optical add / drop circuit, the signal light transmitted through the high-pass filter is transmitted from the transmitting station, When increasing the signal light to the transmission side of the insertion circuit, the signal light transmitted through the low-pass filter is transmitted from the transmitting station.

【0007】上記光分岐挿入回路へ入力する信号光は波
長多重光であり、各波長の信号光は上記光分岐挿入回路
の高域透過フィルタまたは前記低域透過フィルタのいず
れかのみを通過する。
The signal light input to the optical add / drop circuit is wavelength multiplexed light, and the signal light of each wavelength passes through only one of the high-pass filter and the low-pass filter of the optical add / drop circuit.

【0008】上述の構成および方法を用いることによ
り、本発明では光伝送システムを設置した後、光分岐挿
装置の光分岐挿入回路これを構成する部品を交換す
ることなく、また外部から光分岐挿入回路に対して光分
離のための波長制御をすることなく主伝送路または分岐
路の伝送容量を容易に増加させることができる。
By using the above configuration and method, according to the present invention, after the optical transmission system is installed, the optical add / drop circuit of the optical add / drop device and the components constituting the add / drop circuit are not replaced , and the optical add / drop circuit is externally provided. Light component to insertion circuit
The transmission capacity of the main transmission line or the branch line can be easily increased without performing wavelength control for separation .

【0009】[0009]

【発明の実施の形態】次に、本発明に実施の形態につい
て図面を用いて説明する。図1は本発明の光分岐挿入回
路1aの基本構成を示す。まず局舎6から複数の波長の
信号光が波長多重され送出される。この波長多重された
信号光は分波器4に入力され、2つに分波される。分波
された一方の信号光は低域透過フィルタ3に入力され、
該信号光のうち所定の数の短波長側の光信号のみが透過
する。この透過光は光分岐挿入回路1aの分岐路から局
舎8aに送られる。分波器4で分波された他方の信号光
は高域透過フィルタ2に入力され、該信号光のうち所定
の数の長波長側の光信号のみが透過する。局舎8aから
は分岐路から入力された信号光と同じ数および波長の光
が光分岐挿入回路1aへ送出される。高域透過フィルタ
2を透過した信号光と局舎8aから送出される挿入光
は、合波器5によって合波され、光分岐挿入回路1aの
出力光として局舎7へ送られる。なお、図1以下の各実
施の形態では、低域透過フィルタとは所定の波長cより
短波長の信号光を透過させるフィルタであり、高域透過
フィルタとは上記所定の波長cより長波長の信号光を透
過させるフィルタであるものとする。
Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a basic configuration of an optical add / drop circuit 1a according to the present invention. First, signal light of a plurality of wavelengths is wavelength-multiplexed and transmitted from the station 6. The wavelength-multiplexed signal light is input to the demultiplexer 4 and split into two. One of the split signal lights is input to the low-pass filter 3, and
Only a predetermined number of optical signals on the short wavelength side of the signal light are transmitted. The transmitted light is sent from the branch of the optical add / drop circuit 1a to the office 8a. The other signal light demultiplexed by the demultiplexer 4 is input to the high-pass filter 2, and only a predetermined number of optical signals on the long wavelength side of the signal light are transmitted. Light having the same number and wavelength as the signal light input from the branch path is transmitted from the office 8a to the optical add / drop circuit 1a. The signal light transmitted through the high-pass filter 2 and the insertion light transmitted from the station 8a are multiplexed by the multiplexer 5 and sent to the station 7 as output light of the optical add / drop circuit 1a. 1 and the following embodiments, the low-pass filter is a filter that transmits signal light having a wavelength shorter than the predetermined wavelength c, and the high-pass filter is a filter that has a longer wavelength than the predetermined wavelength c. It is assumed that the filter transmits signal light.

【0010】図2は図1の光分岐挿入回路1aを用いた
光伝送システムの基本動作を示している。例えば局舎6
から波長b、d、e、f(ただし、b<d<e<f)の
4つの信号光が波長多重され送出される。これら4つの
信号光は分波器4で2つに分岐される。分岐光の一方は
低域透過フィルタ3に入力され、波長bのみが該フィル
タ3を透過し局舎8aに送られる。分波器4によって分
岐された他方の信号光は高域透過フィルタ2に入力さ
れ、波長d、e、fが透過する。局舎8aからは波長b
の光が送出される。合波器5は高域透過フィルタ2から
送出される波長d、e、fの信号光と局舎8aから送出
される波長bの光を合波する。この結果、光分岐挿入回
路1aからは局舎6から送出された波長b、d、e、f
の信号光と同じ4つの波長の信号光が局舎7へ送られ
る。
FIG. 2 shows a basic operation of an optical transmission system using the optical add / drop circuit 1a of FIG. For example, office building 6
, Four signal lights having wavelengths b, d, e, and f (where b <d <e <f) are wavelength-multiplexed and transmitted. These four signal lights are split into two by the splitter 4. One of the branched lights is input to the low-pass filter 3, and only the wavelength b is transmitted through the filter 3 and sent to the office 8a. The other signal light branched by the demultiplexer 4 is input to the high-pass filter 2, and the wavelengths d, e, and f are transmitted. Wavelength b from the office 8a
Is emitted. The multiplexer 5 multiplexes the signal lights of the wavelengths d, e, and f transmitted from the high-pass filter 2 with the light of the wavelength b transmitted from the station 8a. As a result, the wavelengths b, d, e, and f transmitted from the station 6 from the optical add / drop circuit 1a.
Are transmitted to the station 7 with the same four wavelengths.

【0011】図3(a)、(b)は本発明に用いられる
高域透過フィルタと低域透過フィルタの特性を示す模式
図である。高域透過フィルタは特定の波長cより長波長
側の信号光を透過させ、また低域透過フィルタは同じ波
長cより短波長側の信号光を透過させる。透過域と阻止
域では例えば約20から30dBの差を有している。
FIGS. 3A and 3B are schematic diagrams showing characteristics of a high-pass filter and a low-pass filter used in the present invention. The high-pass filter transmits signal light on the longer wavelength side than the specific wavelength c, and the low-pass filter transmits signal light on the shorter wavelength side than the same wavelength c. For example, there is a difference of about 20 to 30 dB between the transmission area and the stop area.

【0012】図4は図2に示した構成において、光分岐
挿入回路1aから局舎8aへの通信容量(すなわち信号
光の数)を増やす場合の例を示している。局舎6は局舎
8aへ送りたい波長aを他の波長b、d、e、fに加え
て波長多重し光分岐挿入装置1aへ送出する。これらの
信号光の波長はa<b<c<d<fの順で長くなってい
る。波長aの信号光は波長bの信号光より短波長なので
低域透過フィルタ3を透過して局舎8aへ送られる。局
舎8aは波長a、bの信号光を光分岐挿入装置1aへ送
出する。この波長a、bの信号光は、光分岐挿入回路1
aにおいて高域透過フィルタ2を透過した波長d、e、
fの光と合波され、局舎7へ送出される。
FIG. 4 shows an example in which the communication capacity (ie, the number of signal lights) from the optical add / drop circuit 1a to the station 8a is increased in the configuration shown in FIG. The station 6 multiplexes the wavelength a desired to be sent to the station 8a with the other wavelengths b, d, e, and f, and sends it to the optical add / drop multiplexer 1a. The wavelengths of these signal lights are longer in the order of a <b <c <d <f. Since the signal light having the wavelength a is shorter in wavelength than the signal light having the wavelength b, the signal light passes through the low-pass filter 3 and is sent to the station 8a. The station 8a sends out the signal lights of the wavelengths a and b to the optical add / drop multiplexer 1a. The signal lights of the wavelengths a and b are supplied to the optical add / drop circuit 1.
a, the wavelengths d, e, transmitted through the high-pass filter 2;
The light is combined with the light of f and transmitted to the station 7.

【0013】図5は図2に示した構成において、局舎6
から局舎7への主伝送路の容量を増やす場合の例を示し
ている。局舎6では局舎7へ主伝送路を経由して送出し
たい波長gを他の波長b、d、e、fに加えて波長多重
し光分岐挿入装置1aへ送出する。これらの信号光の波
長はb<d<e<f<gの順で長くなっている。波長g
の信号光は波長fの信号光より長波長なので波長d、
e、fの波長の信号光と共に高域透過フィルタ2を透過
する。これら波長d、e、f、gの信号光は、局舎8a
から送出される波長bの信号光と共に合波器5にて合波
され、局舎7へ送出される。
FIG. 5 shows a configuration of the station 6 in the configuration shown in FIG.
An example is shown in which the capacity of the main transmission path from the station to the station 7 is increased. In the station 6, the wavelength g to be transmitted to the station 7 via the main transmission path is added to the other wavelengths b, d, e, and f, and the wavelength is multiplexed and transmitted to the optical add / drop multiplexer 1a. The wavelengths of these signal lights are longer in the order of b <d <e <f <g. Wavelength g
Is longer than the signal light of wavelength f, so that the wavelength d,
The light passes through the high-pass filter 2 together with the signal lights of the wavelengths e and f. The signal light having the wavelengths d, e, f, and g is transmitted to the station building 8a.
The signal is multiplexed by the multiplexer 5 together with the signal light of the wavelength b transmitted from the optical network and is transmitted to the station 7.

【0014】図6は、局舎6と局舎7の間の主伝送路に
本発明の光分岐挿入回路を2台、シリーズに配置した構
成を示す。局舎6と局舎7の間に光分岐挿入回路1a、
1bを配置し、光分岐挿入回路1a、1bにはそれぞれ
局舎8aと局舎8bが接続している。
FIG. 6 shows a configuration in which two optical add / drop circuits of the present invention are arranged in a series on a main transmission line between a station 6 and a station 7. An optical add / drop circuit 1a between the office 6 and the office 7,
1b, and offices 8a and 8b are connected to the optical add / drop circuits 1a and 1b, respectively.

【0015】図7は、図6の構成において局舎8a、局
舎8bへの信号光をさらに1波長分増やす場合を示して
いる。局舎6において、もっとも短波長である波長bの
信号光よりさらに短波長aの信号光を加えて送出する。
この波長aの信号光は波長bの信号光と共に、低域透過
フィルタを透過して局舎8a、局舎8bに送られる。局
舎8a、局舎8bからはそれぞれ波長a、bの信号光が
光分岐挿入回路へ送出される。したがって、局舎6が送
出した波長a、b、d、e、fの信号光が局舎7へ送ら
れる。図7では局舎8a、局舎8bへそれぞれ同じ波長
a、bの2つの信号光が送られている。この場合、局舎
8aでは波長aの信号光のみを使用し、局舎8bでは波
長bの信号光を使用する方式が考えられる。最初に分岐
信号光を送る局舎の数だけの信号光を分岐させておき、
更に分岐信号光を追加し、この追加した信号光を通信容
量を増やしたい局舎が利用する方式が可能である。送信
局である局舎6に一番近い光分岐挿入回路1aから順に
該回路に配置する低域透過フィルタ3の特性を変化さ
せ、短い波長から順に1つの信号光を局舎毎に分岐させ
ていく構成も考えられる。このような場合は信号光の波
長間隔を0.8nmより大きくしておくことが望まし
い。また分岐信号光を受信する局舎のうち送信局から離
れたものには低域透過フィルタにかえて所定の波長域の
信号光を透過させる帯域透過フィルタを配置することも
できる。
FIG. 7 shows a case where the signal light to the stations 8a and 8b is further increased by one wavelength in the configuration of FIG. At the station 6, a signal light having a shorter wavelength a than the signal light having the shortest wavelength b is added and transmitted.
The signal light having the wavelength a and the signal light having the wavelength b are transmitted through the low-pass filter and sent to the stations 8a and 8b. From the offices 8a and 8b, signal lights of wavelengths a and b are transmitted to the optical add / drop circuit. Therefore, the signal light of the wavelengths a, b, d, e, and f transmitted from the station 6 is sent to the station 7. In FIG. 7, two signal lights of the same wavelengths a and b are transmitted to the stations 8a and 8b, respectively. In this case, it is conceivable that the station 8a uses only the signal light of the wavelength a and the station 8b uses the signal light of the wavelength b. First, the signal light is split into as many as the number of stations that send the split signal light,
Further, a method is possible in which a branch signal light is added, and the added signal light is used by a station that wants to increase the communication capacity. The characteristics of the low-pass filter 3 arranged in the optical add / drop circuit 1a closest to the station 6 which is the transmitting station are changed in order, and one signal light is split in each station sequentially from the shortest wavelength. Many configurations are possible. In such a case, it is desirable to make the wavelength interval of the signal light larger than 0.8 nm. Further, among the stations that receive the branched signal light, those that are distant from the transmitting station may be provided with band-pass filters that transmit signal light in a predetermined wavelength range instead of low-pass filters.

【0016】図8は本発明の光分岐挿入回路の他の構成
を示している。この構成は図1の構成に対し低域透過フ
ィルタ3と高域透過フィルタ2の設置される位置が逆に
なっている。したがって、局舎8aへの分岐路の通信容
量を増やす場合は、すでに使用されている信号光の波長
より長波長の光信号を局舎6にて波長多重して送出す
る。一方、局舎6から局舎7への主伝送路の通信容量を
増やす場合は短波長側の光信号を加える。
FIG. 8 shows another configuration of the optical add / drop circuit of the present invention. In this configuration, the positions at which the low-pass transmission filter 3 and the high-pass transmission filter 2 are installed are reversed with respect to the configuration of FIG. Accordingly, when increasing the communication capacity of the branch path to the station 8a, the station 6 wavelength-multiplexes and transmits an optical signal having a longer wavelength than the wavelength of the signal light already used. On the other hand, when increasing the communication capacity of the main transmission path from the station 6 to the station 7, an optical signal on the short wavelength side is added.

【0017】以上のような本発明の光分岐挿入回路で
は、使用する光分岐挿入回路内の構成に応じて、低域透
過フィルタ又は高域透過フィルタのみを透過する信号光
を追加するだけで、光伝送システム設置後であっても、
光分岐挿入回路を交換することなく主伝送路または分岐
路の通信容量(信号光の数)を増加させることができる
という優れた効果を奏する。
In the optical add / drop circuit of the present invention as described above, depending on the configuration of the optical add / drop circuit used, only the signal light that passes through only the low-pass filter or the high-pass filter is added. Even after installing the optical transmission system,
There is an excellent effect that the communication capacity (the number of signal lights) of the main transmission path or the branch path can be increased without replacing the optical add / drop circuit.

【0018】本発明の光分岐挿入回路で用いられる光信
号の波長は、複数の波長のうちほぼ中間の波長を1.5
585μとしこの波長を中心に0.8n毎の波長差を有
する複数の波長を用いることができる。上記光分岐挿入
回路が配置される光伝送システムにおいて、エルビウム
添加光直接増幅器が用いられる場合、使用する光信号お
よび後から追加する光信号の波長は、該増幅器によって
増幅可能な範囲内のものであることが必要である。また
局舎6から送出される各信号光は、必ず低域透過フィル
タまたは高域透過フィルタのいずれかを透過し、また両
フィルタのいずれをも透過することはない。具体的に
は、上述の実施の形態のように、低域透過フィルタの透
過上限波長と高域透過フィルタの透過下限波長を波長c
(たとえば1.5585μ)とし、局舎6から送出され
る各信号光を、この波長cを除きこれより短波長および
長波長の信号光により構成することができる。
The wavelength of the optical signal used in the optical add / drop circuit of the present invention is set to be approximately 1.5 times the intermediate wavelength among a plurality of wavelengths.
It is possible to use a plurality of wavelengths having a wavelength difference of 585 μm and a wavelength difference of 0.8n around this wavelength. In the optical transmission system in which the optical add / drop circuit is arranged, when an erbium-doped optical direct amplifier is used, the wavelength of the optical signal to be used and the wavelength of the optical signal to be added later are within a range that can be amplified by the amplifier. It is necessary to be. Each signal light transmitted from the station 6 always passes through either the low-pass filter or the high-pass filter, and does not pass through both filters. Specifically, as in the above-described embodiment, the transmission upper-limit wavelength of the low-pass filter and the transmission lower-limit wavelength of the high-pass filter are set to the wavelength c.
(For example, 1.5585 μ), each signal light transmitted from the station 6 can be constituted by signal light having a shorter wavelength and a longer wavelength except for the wavelength c.

【0019】分波器及び合波器は3dBカプラを用いる
ことが望ましい。また低域透過フィルタ及び高域透過フ
ィルタは多層膜構造によって構成できる。
It is desirable to use a 3 dB coupler for the demultiplexer and the multiplexer. Further, the low-pass filter and the high-pass filter can be configured by a multilayer structure.

【0020】[0020]

【発明の効果】以上述べたように、光伝送システムに本
発明の光伝送装置を適用した場合、該システム設置後に
伝送路の容量を増やすとき上記光分岐挿入回路を交換す
る必要がないので、海底中継システムなどにおいて多額
の費用をかけずに光伝送路の通信容量の増加が可能であ
る。
As described above, when the optical transmission apparatus of the present invention is applied to an optical transmission system, it is not necessary to replace the optical add / drop circuit when increasing the capacity of the transmission line after the installation of the system. It is possible to increase the communication capacity of an optical transmission line without incurring a large cost in a submarine repeater system or the like.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の光分岐挿入装置を用いた光伝送システ
ムの構成例を示すブロック図。
FIG. 1 is a block diagram showing a configuration example of an optical transmission system using an optical add / drop multiplexer of the present invention.

【図2】図1の光分岐挿入装置を用いた光伝送方法を示
すブロック図。
FIG. 2 is a block diagram showing an optical transmission method using the optical add / drop multiplexer of FIG.

【図3】本発明の光分岐挿入装置に用いる高域透過フィ
ルタと低域透過フィルタの特性を示す図。
FIG. 3 is a diagram showing characteristics of a high-pass filter and a low-pass filter used in the optical add / drop multiplexer of the present invention.

【図4】分岐路の信号光の数を増加させる場合を示すブ
ロック図。
FIG. 4 is a block diagram showing a case where the number of signal lights in a branch path is increased.

【図5】主伝送路の信号光の数を増加させる場合を示す
ブロック図。
FIG. 5 is a block diagram showing a case where the number of signal lights in a main transmission path is increased.

【図6】2台の光分岐挿入装置を配置した構成例を示す
ブロック図。
FIG. 6 is a block diagram showing a configuration example in which two optical add / drop devices are arranged.

【図7】図6の構成における光伝送方法を示すブロック
図。
FIG. 7 is a block diagram showing an optical transmission method in the configuration of FIG. 6;

【図8】本発明の光分岐挿入装置の他の構成例を示すブ
ロック図。
FIG. 8 is a block diagram showing another configuration example of the optical add / drop multiplexer of the present invention.

【図9】従来の光分岐挿入装置を用いた光伝送システム
の構成例を示すブロック図。
FIG. 9 is a block diagram showing a configuration example of an optical transmission system using a conventional optical add / drop device.

【符号の説明】[Explanation of symbols]

1a、1b、1c 光分岐挿入回路 2 高域透過フィルタ 3 低域透過フィルタ 4 分波器 5 合波器 6、7、8a、8a 局舎 1a, 1b, 1c Optical add / drop circuit 2 High-pass transmission filter 3 Low-pass transmission filter 4 Demultiplexer 5 Combiner 6, 7, 8a, 8a

───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7,DB名) H04B 10/00 H04J 14/00 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. 7 , DB name) H04B 10/00 H04J 14/00

Claims (7)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】 互いに異なる複数の波長の信号光を含む
波長多重信号光を主伝送路に送信する送信局と、 前記第1の局舎と前記主伝送路により接続されており、
前記波長多重信号光から所定の信号光を選択的に分岐し
て分岐信号光を取出すと共に、残余の信号光を通過信号
光として前記主伝送路に送出する光分岐手段を含む光分
岐挿入装置と、 前記主伝送路から出力される前記通過信号光を受信する
受信局とを備えた光伝送装置であって、 前記分岐信号光は所定の第1の波長帯域内にあり、前記
通過信号光は所定の第2の波長帯域内にあり、 前記第1の送信局は、 前記光分岐挿入装置において分岐される信号光を増やす
場合には、前記第1の波長帯域内にあって前記分岐信号
光とは異なる波長を有する信号光を追加して送信し、 前記光分岐挿入装置をそのまま通過させる信号光を増や
す場合には、前記第2の波長帯域内にあって前記通過信
号光とは異なる波長を有する信号光を追加して送信する
追加信号光送出手段を備えている ことを特徴とする光伝
送装置。
1. A signal light having a plurality of wavelengths different from each other.
A transmitting station for transmitting the wavelength multiplexed signal light to the main transmission line, the first station being connected to the main station by the main transmission line,
A predetermined signal light is selectively branched from the wavelength multiplexed signal light.
To extract the branched signal light and pass the remaining signal light through the signal
A light component including an optical branching means for transmitting the light to the main transmission path.
A branch insertion device for receiving the passing signal light output from the main transmission path
An optical transmission device comprising a receiving station, wherein the branch signal light is within a predetermined first wavelength band,
The passing signal light is within a predetermined second wavelength band, and the first transmitting station increases the signal light dropped in the optical add / drop multiplexer.
In the case, the branch signal within the first wavelength band
The signal light having a wavelength different from that of the light is additionally transmitted, and the signal light that passes through the optical add / drop multiplexer is increased.
In this case, the pass signal within the second wavelength band
Add and transmit signal light having a different wavelength from the signal light
An optical transmission device comprising additional signal light transmitting means .
【請求項2】 前記光分岐挿入装置は、さらに前記分岐
信号光と同じ波長の信号光を前記通過信号光に合波する
光挿入手段を備えていることを特徴とする光伝送装置。
2. The optical add / drop multiplexer further comprises:
A signal light having the same wavelength as the signal light is multiplexed with the passing signal light.
An optical transmission device comprising an optical insertion unit .
【請求項3】 前記光分岐手段は、前記第1の波長帯域
内にある波長の光を反射をさせ、前記第2の波長帯域内
にある波長の光を透過させる波長固定フィルタを含んで
いることを特徴とする請求項1又は請求項2記載の光伝
送装置。
3. The optical branching means according to claim 1 , wherein:
To reflect light having a wavelength within the second wavelength band.
Including a fixed wavelength filter that transmits light of a certain wavelength
The optical transmission device according to claim 1 or 2, wherein
【請求項4】 前記光分岐手段は、前記波長多重信号光
を分岐して第1の分岐信号光と第2の分岐信号光をそれ
ぞれ出力する光分岐器と、 前記第1の分岐信号光から前記第1の波長帯域内にある
波長の光を選択的に透過させて前記分岐信号光を出力す
る第1の波長固定フィルタと、 前記第2の分岐信号光から前記第2の波長帯域内にある
波長の光を選択的に透 過させて前記通過信号光を出力す
る第2の波長固定フィルタとを含んでいることを特徴と
する請求項1又は請求項2記載 の光伝送装置。
4. The wavelength division multiplexing signal light according to claim 1 , wherein
And splits the first split signal light and the second split signal light into
Optical splitters for outputting the respective signals, and the optical splitters are within the first wavelength band from the first split signal light.
And selectively transmitting light having a wavelength to output the branched signal light.
A first wavelength-locked filter, and a second wavelength band within the second wavelength band from the second branch signal light.
Outputs the passing signal light by selectively permeable bulk light of wavelength
And a second fixed wavelength filter.
The optical transmission device according to claim 1 or 2, wherein
【請求項5】 前記第1の波長帯域は、前記第2の波長
帯域よりも短波長側に存し、前記波長固定フィルタは、
低域透過フィルタであることを特徴とする請求項3記載
の光伝送装置。
5. The method according to claim 1, wherein the first wavelength band is the second wavelength.
Exists on the shorter wavelength side than the band, the wavelength fixed filter,
The optical transmission device according to claim 3 , wherein the optical transmission device is a low-pass filter .
【請求項6】 前記第1の波長帯域は、前記第2の波長
帯域よりも長波長側に存し、 前記波長固定フィルタは、高域透過フィルタであること
を特徴とする請求項3記載 の光伝送装置。
6. The apparatus according to claim 1, wherein the first wavelength band is the second wavelength.
Exist on the longer wavelength side than the band, and the wavelength fixed filter is a high-pass filter.
The optical transmission device according to claim 3, wherein:
【請求項7】 互いに異なる複数の波長の信号光を含む
波長多重信号光を主伝送路に送信する送信局と、 前記送信局舎と前記主伝送路により接続されており、前
記波長多重信号光から所定の信号光を選択的に分岐して
分岐信号光を取出すと共に、残余の信号光を通過信号光
として前記主伝送路に送出する光分岐手段を含む光分岐
挿入装置と、 前記主伝送路から出力される前記通過信号光を受信する
受信局とを備えた光伝送装置における光伝送方法であっ
て、 前記分岐信号光は所定の第1の波長帯域内にあり、前記
通過信号光は所定の第2の波長帯域内にあり、 前記光分岐手段は、前記第1の波長帯域内にある波長の
光を反射をさせ、前記第2の波長帯域内にある波長の光
を透過させる波長固定フィルタを含んでおり、前記光分
岐挿入装置において分岐される信号光を増やす場合に
は、前記送信局から前記第1の波長帯域内にあって前記
分岐信号光とは異なる波長を有する信号光を追加して送
信し、 前記光分岐挿入装置をそのまま通過させる信号光を増や
す場合には、前記送信局から前記第2の波長帯域内にあ
って前記通過信号光とは異なる波長を有する信号光を追
加して送信する ことを特徴とする光伝送方法。
7. Including signal light of a plurality of wavelengths different from each other.
A transmitting station for transmitting the wavelength multiplexed signal light to the main transmission line, the transmission station building being connected to the main transmission line,
A predetermined signal light is selectively branched from the WDM signal light.
Extracts the split signal light and passes the remaining signal light through the signal light
Optical branching including optical branching means for sending out to the main transmission line as
An insertion device for receiving the passing signal light output from the main transmission path
An optical transmission method in an optical transmission device having a receiving station.
The branch signal light is within a predetermined first wavelength band,
The passing signal light is within a predetermined second wavelength band, and the optical branching unit is configured to output a signal having a wavelength within the first wavelength band.
Reflect light, and emit light having a wavelength within the second wavelength band.
A wavelength fixing filter for transmitting light,
When increasing the signal light to be branched in the branch insertion device
Is within the first wavelength band from the transmitting station and
Signal light having a wavelength different from that of the branched signal light is added and transmitted.
And Shin, Ya increase as a signal to pass light through the optical add drop apparatus
In the second wavelength band from the transmitting station.
Signal light having a wavelength different from that of the passing signal light.
Optical transmission method characterized by pressing and send.
JP9076753A 1997-03-28 1997-03-28 Optical add / drop circuit and optical transmission method Expired - Lifetime JP3039430B2 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP9076753A JP3039430B2 (en) 1997-03-28 1997-03-28 Optical add / drop circuit and optical transmission method
FR9803821A FR2761484A1 (en) 1997-03-28 1998-03-27 Add-drop optical multiplexer unit for long distance communication

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9076753A JP3039430B2 (en) 1997-03-28 1997-03-28 Optical add / drop circuit and optical transmission method

Publications (2)

Publication Number Publication Date
JPH10276129A JPH10276129A (en) 1998-10-13
JP3039430B2 true JP3039430B2 (en) 2000-05-08

Family

ID=13614359

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Application Number Title Priority Date Filing Date
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Country Status (2)

Country Link
JP (1) JP3039430B2 (en)
FR (1) FR2761484A1 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2013128556A1 (en) * 2012-02-27 2015-07-30 富士通株式会社 Optical signal branching apparatus and optical transmission system
WO2016047092A1 (en) * 2014-09-25 2016-03-31 日本電気株式会社 Cable coupling, wavelength-multiplexed optical communication system, and wavelength-multiplexed-optical-signal branching method

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JPH10276129A (en) 1998-10-13

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