JP2006060734A - Optical transmission system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a reliable redundant optical transmission apparatus which is capable of high-speed communication with reduced light loss and simple configuration. <P>SOLUTION: The optical transmission system comprises a transmitting terminal for outputting an optical signal to an optical transmission line, an optical relay section for relaying the optical signal from the transmitting terminal, a receiving terminal for receiving the optical signal relayed by the optical relay section, and a monitoring section for monitoring the optical transmission line and outputting a result of monitoring. In the optical transmission system, the optical transmission line includes a plurality of first-half optical transmission lines each connected to the transmitting terminal and the optical relay section for transmitting the optical signal, and two or more latter-half optical transmission lines each connected to the optical relay section and the receiving terminal for transmitting the optical signal, and is made redundant in each of the first half and the latter half. The transmitting terminal outputs an optical signal of a wavelength corresponding to one of the plurality of first-half transmission lines in accordance with the result of monitoring and for the optical relay section, the latter-half optical transmission line to be the output destination of the optical signal is predetermined in accordance with the wavelength of the optical signal transmitted for each of the plurality of first-half optical transmission lines. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

この発明は、光信号を送信する局から中継地点を経由して、複数の受信地点へ信号を接続する光ネットワークにおいて、障害を回避するために複数の経路で光送信地点と光受信地点を接続する光信号切替装置に関するものである。   In an optical network in which a signal is transmitted from a station transmitting an optical signal via a relay point to a plurality of reception points, the optical transmission point and the optical reception point are connected by a plurality of routes in order to avoid a failure. The present invention relates to an optical signal switching device.

各種の障害による通信への影響を緩和することができる従来のポイント−マルチポイント光伝送システムの一例として、特許文献１「多段光分岐ポイント−マルチポイント光伝送システム」があり、この構成を図９に示す。
この図で示される従来技術は、センタ装置の光送受信機１０１とユーザ装置１０６とを光分岐素子１０４ａ，１０４ｂ及び光ファイバ伝送路１０３ａ，１０３ｂ，１０５で接続する構成である。そして、光分岐素子１０４ａのセンタ装置側に複数のポートを設け、センタ装置と光分岐素子１０４ａとの間に複数の光ファイバ伝送路１０３ａ，１０３ｂを設け、センタ装置に複数の光ファイバ伝送路の内、使用する光ファイバ伝送路を選択する経路選択手段１０２を備えている。 As an example of a conventional point-multipoint optical transmission system that can alleviate the influence of various failures on communication, there is Patent Document 1 “Multi-stage optical branch point-multipoint optical transmission system”. Shown in
The prior art shown in this figure has a configuration in which an optical transceiver 101 of a center apparatus and a user apparatus 106 are connected by optical branching elements 104a and 104b and optical fiber transmission lines 103a, 103b, and 105. A plurality of ports are provided on the center device side of the optical branching element 104a, a plurality of optical fiber transmission paths 103a and 103b are provided between the center apparatus and the optical branching element 104a, and a plurality of optical fiber transmission paths are provided in the center apparatus. Among them, route selection means 102 for selecting an optical fiber transmission line to be used is provided.

光分岐素子１０４ａ，１０４ｂとセンタ装置の間を接続する光ファイバ伝送路１０３ａに障害が発生した場合は、センタ装置に配置した経路選択手段１０２が使用するファイバを障害の発生していない光ファイバ伝送路１０３ｂへ切り替え、障害を回避することができる。
特開平８−２４２２０７号公報「多段光分岐ポイント―マルチポイント光伝送システム」 When a failure occurs in the optical fiber transmission path 103a connecting the optical branching elements 104a and 104b and the center apparatus, the fiber used by the path selection unit 102 arranged in the center apparatus is transmitted through the optical fiber without any failure. Switching to the path 103b can avoid a failure.
Japanese Patent Application Laid-Open No. 8-242207 "Multi-stage optical branch point-multi-point optical transmission system"

従来の技術は、光ファイバ伝送路の障害に対して冗長経路を持ち障害切替を行うことはできたが、センタ装置とユーザ装置の間が光分岐素子で接続されているためにセンタ装置から出力された光信号は全てのユーザ装置へ分配されてしまい、ユーザ装置毎に異なる信号を送受することができない。このため、ユーザ装置毎に異なる通信を行うためには、時分割多重によってユーザ装置毎の信号を束ねて送受する必要があり、ユーザ装置毎の通信速度が限定されるという課題がある。
また、光分岐素子を用いて信号を分配しているため、光分岐時及び光合流時に大きな光損失が発生し、分岐数を増大すると信号強度が弱まるために信号速度が制限されるという課題がある。 Although the conventional technology has been able to switch the failure with a redundant path against the failure of the optical fiber transmission line, the center device and the user device are connected by an optical branching element, so the output from the center device The optical signal thus distributed is distributed to all the user devices, and different signals cannot be transmitted and received for each user device. For this reason, in order to perform different communication for each user apparatus, it is necessary to bundle and transmit signals for each user apparatus by time division multiplexing, and there is a problem that the communication speed for each user apparatus is limited.
In addition, since the signal is distributed using the optical branching element, a large optical loss occurs at the time of the optical branching and the optical merging, and the signal speed is limited because the signal strength is weakened when the branching number is increased. is there.

この発明は、上記のような課題を解消するためになされたもので、各ユーザ装置とセンタ装置の間を時分割処理ではなく、波長多重技術を用いて接続して、時分割処理に要する複雑な処理を軽減すること、また、波長の占有と中継地点での光分岐損失の抑圧によって通信速度を高速化すること、及び、中継地点では外部からの制御を必要としない単純な構成で伝送路の冗長化を実現し、信頼性の高いネットワークを形成する光伝送システムを得ることを目的とする。   The present invention has been made to solve the above-described problems. The user equipment and the center apparatus are connected by using wavelength multiplexing technology instead of time division processing, and the complexity required for time division processing is achieved. The transmission speed with a simple configuration that does not require external control at the relay point, and the communication speed is increased by suppressing the occupancy of the wavelength and suppressing the optical branching loss at the relay point. It is an object of the present invention to obtain an optical transmission system that realizes redundancy and forms a highly reliable network.

この発明に係る光伝送システムは、光伝送路に光信号を出力する送信端、前記送信端からの光信号を中継する光中継部、前記光中継部で中継された光信号を受信する受信端、前記光伝送路を監視して監視結果を出力する監視モニタ部を備えた光伝送システムであって、
前記光伝送路は、前記送信端と前記光中継部とに接続して光信号を伝送する複数の前半光伝送路と、前記光中継部と前記受信端とに接続して光信号を伝送する２以上の後半光伝送路とを有して前半／後半でそれぞれ冗長化されており、
前記送信端は、前記監視結果に応じて前記複数の前半光伝送路のうち該当する前半光伝送路に該当する波長の光信号を出力し、
前記光中継部は、前記複数の前半光伝送路毎に伝送されてきた光信号の波長に応じてその光信号の出力先の前記後半光伝送路が予め決められている
ことを特徴とする。 An optical transmission system according to the present invention includes a transmitting end that outputs an optical signal to an optical transmission line, an optical repeater that relays an optical signal from the transmitting end, and a receiving end that receives an optical signal relayed by the optical repeater , An optical transmission system including a monitoring monitor unit that monitors the optical transmission line and outputs a monitoring result,
The optical transmission path is connected to the transmitting end and the optical repeater to transmit an optical signal, and is connected to the optical repeater and the receiving end to transmit an optical signal. It has two or more second half optical transmission lines and is made redundant in the first half / second half,
The transmitting end outputs an optical signal having a wavelength corresponding to a corresponding first half optical transmission path among the plurality of first half optical transmission paths according to the monitoring result,
The optical repeater is characterized in that the latter-half optical transmission path of the output destination of the optical signal is determined in advance according to the wavelength of the optical signal transmitted for each of the plurality of first-half optical transmission paths.

以上のようにこの発明によれば、中継地点の中継部に外部からの複雑な切替え制御を要しない単純な受動光素子を用いることができ、波長によって経路を振り分けるので、光伝送損失を小さくし、受信端が受信する光信号強度を比較的大きくできる。また、送信端で波長を切替えるのみで送信端から受信端までの伝送路を少なくとも４つ選択することができ、簡易で低コストな構成で障害切替えを行うことができる。また、受信端に対して波長を占有することで高速通信が可能である。   As described above, according to the present invention, a simple passive optical element that does not require complicated switching control from the outside can be used for the relay unit at the relay point, and the path is distributed according to the wavelength, so that the optical transmission loss is reduced. The optical signal intensity received by the receiving end can be made relatively large. Further, at least four transmission paths from the transmission end to the reception end can be selected only by switching the wavelength at the transmission end, and failure switching can be performed with a simple and low-cost configuration. Further, high-speed communication is possible by occupying the wavelength with respect to the receiving end.

実施の形態１．
冗長度を持たせ、かつ分岐損を無くして波長多重を用いて回路構成を単純化した冗長光信号伝送装置及びシステムを説明する。
図１は、本実施の形態における冗長光信号伝送装置及びシステムの構成を示す図である。また図２は、本実施の形態における光合分波部の詳細構成を示す図である。図において、送信端は、波長λ１ないしλ４に波長を切替えられる（光信号用）可変光源１と、これからの光信号入力を波長により異なる出力ポートに分けて出力する分波部２と、監視光源９ａ，９ｂと、その監視モニタ１１ａ，１１ｂと、この監視光源からの信号と分波部２の出力とを入力とし、中継地点（部）へ出力する合分波器１０ａ，１０ｂと、監視モニタ信号で可変光源の波長を切替制御する切替制御部１３とで構成される。そしてそれぞれの出力を、前半光伝送路を構成する複数の単一伝送路である光伝送路３ａ，３ｂ経由で中継地点へ伝送する。
また中継地点は、監視光反射器１２ａ，１２ｂと、例えば波長λ１とλ２のグループと、波長λ３とλ４のグループとを入力とし、波長に応じて所定の出力ポートに出力する合分波器４とで構成される。そしてそれぞれの出力を、後半伝送路を構成する複数の単一伝送路である光伝送路５，６経由で受信端へ伝送する。
また受信端は、複数の光伝送路からの光信号を合わせて合波する合波部７と、光受信器８とで構成される。
なお図１の構成では、動作説明を簡略化するために送信端と受信端とをそれぞれ１台づつの構成として示しているが、それぞれ複数の構成としてもよい。
また更に受信端では、光受信器８は、中継地点からの出力側の光伝送路５，６からの光信号を受信し、これらの光伝送路５、６の障害を送信端の監視モニタに伝える機能を備えている。 Embodiment 1 FIG.
A redundant optical signal transmission apparatus and system in which redundancy is provided and the circuit configuration is simplified by using wavelength multiplexing with no branching loss will be described.
FIG. 1 is a diagram illustrating a configuration of a redundant optical signal transmission apparatus and system according to the present embodiment. FIG. 2 is a diagram showing a detailed configuration of the optical multiplexing / demultiplexing unit in the present embodiment. In the figure, the transmission end includes a variable light source 1 (for optical signals) whose wavelength can be switched to wavelengths λ1 to λ4, a demultiplexing unit 2 that outputs the optical signal input divided into different output ports depending on the wavelength, and a monitoring light source 9a and 9b, their monitoring monitors 11a and 11b, signals from the monitoring light source and the output of the demultiplexing unit 2 as inputs, and outputs to the relay point (unit), the demultiplexers 10a and 10b, and the monitoring monitor It is comprised with the switching control part 13 which switches and controls the wavelength of a variable light source with a signal. Each output is transmitted to a relay point via optical transmission lines 3a and 3b, which are a plurality of single transmission lines constituting the first half optical transmission line.
Further, the relay point is an optical multiplexer / demultiplexer 4 that receives the monitoring light reflectors 12a and 12b, for example, a group of wavelengths λ1 and λ2 and a group of wavelengths λ3 and λ4, and outputs them to a predetermined output port according to the wavelength. It consists of. Each output is transmitted to the receiving end via optical transmission lines 5 and 6 which are a plurality of single transmission lines constituting the latter half transmission line.
The receiving end includes a multiplexing unit 7 that combines and combines optical signals from a plurality of optical transmission lines, and an optical receiver 8.
In the configuration of FIG. 1, in order to simplify the description of the operation, the transmission end and the reception end are shown as a single configuration, but a plurality of configurations may be used.
Further, at the receiving end, the optical receiver 8 receives optical signals from the optical transmission paths 5 and 6 on the output side from the relay point, and the failure of these optical transmission paths 5 and 6 is used as a monitoring monitor at the transmitting end. Has the ability to communicate.

即ち、この発明に係る光伝送システムは、複数の波長の光信号を出力する光信号用光源と、
上記複数波長の光信号と監視用信号とを異なる光伝送路に送信する合分波器を複数台と、
上記各光伝送路の障害を監視する上記監視用信号を上記合分波器に出力する監視光源を複数個と、
上記光伝送路から反射して返ってくる上記監視用信号を上記合分波器経由でモニタする監視モニタを複数個と、
複数の上記監視モニタによる監視結果により上記光信号用光源の波長を切替制御する切替制御部、とを備えた光信号伝送装置と、
光中継部と、受信端と、監視モニタ、とで構成される。
または、光伝送路が、送信端と光中継部間に接続されて光信号を伝送する複数の単一伝送路からなる前半光伝送路と、上記光中継部と上記受信端間に接続されて光信号を伝送する複数の単一伝送路からなる後半光伝送路とで構成され、
上記光伝送路に光信号を出力する送信端として、上記前半光伝送路を構成する単一伝送路毎にそれぞれ複数の異なる波長の光信号を出力し、上記監視モニタ部による監視結果に応じて上記光伝送路に出力する光信号の上記波長を制御する光信号伝送装置と、
光中継部と、受信端と、監視モニタ、とで構成される。
この構成による光信号伝送システムの動作を説明する。
送信端側におかれた可変光源１の出力信号は、切替制御部１３からの制御で波長をλ１からλ４まで変化させることができ、分波部２を介して波長がλ１及びλ２の場合は光伝送路３ａへ、波長がλ３及びλ４の場合は光伝送路３ｂへ出力される。光伝送路３ａと３ｂは、それぞれ中継地点へ接続され、片経路に障害が発生したときのために経路冗長されている。 That is, an optical transmission system according to the present invention includes an optical signal light source that outputs optical signals having a plurality of wavelengths,
A plurality of multiplexers / demultiplexers for transmitting the optical signals of the plurality of wavelengths and the monitoring signal to different optical transmission lines;
A plurality of monitoring light sources for outputting the monitoring signal for monitoring a failure of each optical transmission line to the multiplexer / demultiplexer;
A plurality of monitoring monitors for monitoring the monitoring signal reflected and returned from the optical transmission line via the multiplexer / demultiplexer;
An optical signal transmission device comprising: a switching control unit that switches and controls the wavelength of the light source for the optical signal according to the monitoring results of the plurality of monitoring monitors;
An optical repeater, a receiving end, and a monitoring monitor are included.
Alternatively, the optical transmission line is connected between the transmission end and the optical repeater, and is connected between the first half optical transmission line composed of a plurality of single transmission lines for transmitting optical signals, and between the optical repeater and the reception end. It consists of a latter half optical transmission line consisting of multiple single transmission lines that transmit optical signals,
As a transmitting end for outputting an optical signal to the optical transmission line, an optical signal having a plurality of different wavelengths is output for each single transmission line constituting the first half optical transmission line, and according to a monitoring result by the monitoring monitor unit An optical signal transmission device for controlling the wavelength of the optical signal output to the optical transmission line;
An optical repeater, a receiving end, and a monitoring monitor are included.
The operation of the optical signal transmission system with this configuration will be described.
The output signal of the variable light source 1 placed on the transmission end side can change the wavelength from λ1 to λ4 by the control from the switching control unit 13, and when the wavelength is λ1 and λ2 via the demultiplexing unit 2, When the wavelengths are λ3 and λ4, the light is output to the optical transmission line 3a. Each of the optical transmission lines 3a and 3b is connected to a relay point, and is redundant in case a failure occurs in one path.

監視光源９ａと９ｂから出力された監視用波長（λｍｏｎ）の信号は、合分波器１０ａ，１０ｂを介して光伝送路３ａと３ｂで中継地点まで伝送され、監視光反射器で反射されて折返し光として再び送信端まで戻ってきた後に、監視モニタ１１ａ，１１ｂでモニタする。
こうして、監視モニタの出力によって、光伝送路３ａ，３ｂの障害状態を監視することができ、この信号を用いて切替制御部１３は、可変光源１の出力波長をコントロールして障害の発生していない側の光伝送路３へ信号を出力する。図１では、仮に光伝送路３ａに障害が発生した図としているが、この場合は、可変光源１の出力波長はλ３又はλ４に制御され、光伝送路３ｂを通じて信号伝送される。 The signal of the monitoring wavelength (λmon) output from the monitoring light sources 9a and 9b is transmitted to the relay point via the optical transmission lines 3a and 3b via the multiplexers / demultiplexers 10a and 10b, and reflected by the monitoring light reflector. After returning to the transmission end again as return light, monitoring is performed by the monitoring monitors 11a and 11b.
Thus, the failure state of the optical transmission lines 3a and 3b can be monitored by the output of the monitoring monitor. Using this signal, the switching control unit 13 controls the output wavelength of the variable light source 1 to cause a failure. A signal is output to the optical transmission line 3 on the non-side. In FIG. 1, it is assumed that a failure has occurred in the optical transmission line 3a. In this case, the output wavelength of the variable light source 1 is controlled to λ3 or λ4, and the signal is transmitted through the optical transmission line 3b.

中継地点に配置された合分波部４は、複数の入力ポートと複数の出力ポートを持ち、各入力ポートに入力された信号の波長に応じて出力ポートを振り分ける特性を持つ。
図２に、合分波部４の一構成例を示す。
光伝送路３ａから入力されたλ１とλ２の信号は、それぞれ光伝送路５と６に出力され、光伝送路３ｂから入力されたλ３とλ４の信号も、それぞれ光伝送路５と６に出力される。光分岐ではなく、分波部１４ａ，１４ｂ（分波手段）と合波部１５ａ，１５ｂ（合波手段）を用いるため、原理的には、光損失が発生しない。図２では、２ポートの合波手段と分波手段を用いる例を示すが、多波長を扱う合分波部を用いてもよいし、１つのデバイスでこれらの機能を実現する周回性導波路型回折格子（周回性ＡＷＧ）などの光素子を適用しても構わない。この合波部は、外部からの複雑な切替制御などは必要としない単純な受動光素子であり、信頼性が高い。 The multiplexing / demultiplexing unit 4 disposed at the relay point has a plurality of input ports and a plurality of output ports, and has a characteristic of distributing the output ports according to the wavelength of the signal input to each input port.
FIG. 2 shows a configuration example of the multiplexing / demultiplexing unit 4.
The λ1 and λ2 signals input from the optical transmission path 3a are output to the optical transmission paths 5 and 6, respectively, and the λ3 and λ4 signals input from the optical transmission path 3b are also output to the optical transmission paths 5 and 6, respectively. Is done. In principle, no optical loss occurs because the demultiplexing sections 14a and 14b (demultiplexing means) and the multiplexing sections 15a and 15b (multiplexing means) are used instead of the optical branching. FIG. 2 shows an example using two-port multiplexing means and demultiplexing means. However, a multiplexing / demultiplexing section that handles multiple wavelengths may be used, or a circular waveguide that realizes these functions with one device. An optical element such as a type diffraction grating (circumferential AWG) may be applied. This multiplexing unit is a simple passive optical element that does not require complicated switching control from the outside, and has high reliability.

合分波部４を通過した光信号は、波長λによって光伝送路５又は光伝送路６に出力される。仮に光伝送路３ａと６に同時に障害が発生した場合には、可変光源１がλ３を出力することによって光伝送路３ｂと５を通る経路を選択することができ、受信端へ到達することができる。
受信端では、光伝送路５及び６から入力されてきた光信号が合波部７を介して、光受信機で受信される。 The optical signal that has passed through the multiplexing / demultiplexing unit 4 is output to the optical transmission line 5 or the optical transmission line 6 depending on the wavelength λ. If a failure occurs in the optical transmission lines 3a and 6 at the same time, the variable light source 1 outputs λ3, so that a path passing through the optical transmission lines 3b and 5 can be selected, and the reception end can be reached. it can.
At the receiving end, the optical signals input from the optical transmission lines 5 and 6 are received by the optical receiver via the multiplexing unit 7.

図３は、切替制御部１３の動作を示すフロー図である。図１の構成では監視光反射器１２ａ，１２ｂは受信端には置かれていないが、例えば、中継地点より前の光伝送路に障害が発生した場合に、一時的に障害調査用として、光信号用可変光源１の波長を光伝送路５または光伝送路６の波長に変更して、光受信器８で受信の可否を調べれば、受信できなかった方の光伝送路５、６の障害も監視できる。先ず中継地点に置かれた監視反射器から反射されて返ってくる監視用波長の信号を監視モニタで受けて、更に一時的に光信号の波長を変えて受信端の光受信器８でその受信の可否を調べて別途連絡すれば、図３のフローにより、どの波長の光源を可変光源で送信するかを決めることが出来る。即ち受信端は、光伝送路５、６の障害を送信端の監視モニタに伝える機能がある。
この波長切替制御における波長の選択は、図３のフローに示された切替制御部１３が行う、例えばＳ１０１の伝送路の障害検出ステップ、Ｓ１０２の障害の発生が中継地点より前か後かの調査ステップ、Ｓ１０３ないしＳ１０７及びＳ１２１ないしＳ１２５等の光伝送路の障害が中継地点より前か後かの調査ステップ、及びその結果に基づいてＳ１１１ないしＳ１１４とＳ１３１ないしＳ１３４の組合わせに基づいて上記光源の波長を決めるステップ、の各ステップを見れば明らかなので、詳細記述は省略する。 FIG. 3 is a flowchart showing the operation of the switching control unit 13. In the configuration of FIG. 1, the monitoring light reflectors 12a and 12b are not placed at the receiving end. However, for example, when a failure occurs in the optical transmission path before the relay point, If the wavelength of the signal variable light source 1 is changed to the wavelength of the optical transmission line 5 or 6 and the optical receiver 8 checks whether or not reception is possible, the failure of the optical transmission lines 5 and 6 that could not be received. Can also be monitored. First, the monitoring wavelength signal reflected and returned from the monitoring reflector placed at the relay point is received by the monitoring monitor, and the wavelength of the optical signal is changed temporarily, and the optical receiver 8 at the receiving end receives the signal. If it is determined whether or not it is possible to communicate separately, it is possible to determine which wavelength light source is transmitted by the variable light source according to the flow of FIG. That is, the receiving end has a function of transmitting a failure of the optical transmission lines 5 and 6 to the monitoring monitor of the transmitting end.
The wavelength selection in this wavelength switching control is performed by the switching control unit 13 shown in the flow of FIG. 3, for example, a failure detection step of the transmission path in S101, and an investigation whether the occurrence of the failure in S102 is before or after the relay point Steps, S103 to S107 and S121 to S125, etc., for investigating whether the failure of the optical transmission path is before or after the relay point, and based on the result, based on the combination of S111 to S114 and S131 to S134, Detailed description is omitted because it is clear from the steps of determining the wavelength.

以上のように、図１の構成では、送信端から受信端までを接続する経路が中継地点までの２通りと受信端までの２通りの組み合わせ４通りあるのに対して、送信端の可変光源１が出力できる波長は、λ１からλ４の４通りから選択できる。このため、冗長化された光伝送路３ａ，３ｂ及び光伝送路５，６のそれぞれで障害が発生しても、送信端の波長を制御することで受信端までの経路を選択することが可能である。   As described above, in the configuration of FIG. 1, there are four combinations of two routes from the transmission end to the reception end, that is, two ways to the relay point and two points from the reception end to the variable light source at the transmission end. The wavelength that 1 can output can be selected from four wavelengths from λ1 to λ4. For this reason, even if a failure occurs in each of the redundant optical transmission paths 3a and 3b and the optical transmission paths 5 and 6, it is possible to select a path to the receiving end by controlling the wavelength of the transmitting end. It is.

こうして、送信端と受信端の間で波長を占有することで高速な通信を実現することができる。また、送信端に複数の可変光源を設け波長多重技術を用いて波長多重伝送とした場合は、より多くの情報を伝送することができ、更に送信端と受信端とが一対複数の場合は、送信端と複数の受信端それぞれの間で個別の波長を用い高速な通信を実現することができる。また、中継地点での信号の分配に原理的に光損失のない合分波手段を適用するため、光伝送損失が小さく、ユーザ装置数を増大することができ、光信号強度を大きくできるために高速信号を扱うことが可能である。中継地点の合分波手段は、外部から制御が不要で信頼性が高い受動素子なので、簡易で低コストな構成で切替を行うことができる。   Thus, high-speed communication can be realized by occupying the wavelength between the transmitting end and the receiving end. In addition, when a plurality of variable light sources are provided at the transmission end and wavelength multiplexing transmission is performed using wavelength multiplexing technology, more information can be transmitted, and when there are a plurality of transmission ends and reception ends, High-speed communication can be realized using individual wavelengths between the transmitting end and the plurality of receiving ends. In addition, since optical multiplexing and demultiplexing means without optical loss is applied in principle to signal distribution at relay points, optical transmission loss is small, the number of user devices can be increased, and optical signal intensity can be increased. It is possible to handle high-speed signals. Since the multiplexing / demultiplexing means at the relay point is a passive element that does not require external control and has high reliability, switching can be performed with a simple and low-cost configuration.

実施の形態２．
他の冗長光信号伝送装置及びシステムの構成を説明する。
図４は、本実施の形態における冗長光信号伝送装置及びシステムの構成を示す図である。また、図５は、本実施の形態における光合分波器の詳細構成を示す図である。これらの図において図１の構成と異なることは、可変光源１ａ，１ｂ，１ｃの数を複数にし、複数の光信号を多重化して伝送している。合分波部４ｂは、例えば図４対応では（λ１，λ５，λ９とλ２，λ６，λ１０）及び（λ３，λ７，λ１１とλ４，λ８，λ１２）の２つのグループの入力ポートと、（λ１，λ５，λ９とλ３，λ７，λ１１）及び（λ２，λ６，λ１０とλ４，λ８，λ１２）２つのグループの出力ポートを持つものである。図４対応では（λ１，λ３）と、（λ２，λ４）と、（λ５，λ７）と、（λ６，λ８）と、（λ９，λ１１）と、（λ１０，λ１２）との複数の出力を行う。
図５では、更に一般的な記述をしており、２つの入力ポートからの図示記載の波長多重信号を、その含まれる波長に応じて２つの出力ポートのいずれかに出力している。この機能は、例えば導波路型回折格子（ＡＷＧ）で得られる。 Embodiment 2. FIG.
The configuration of another redundant optical signal transmission apparatus and system will be described.
FIG. 4 is a diagram showing the configuration of the redundant optical signal transmission apparatus and system in the present embodiment. FIG. 5 is a diagram showing a detailed configuration of the optical multiplexer / demultiplexer according to the present embodiment. In these drawings, the difference from the configuration of FIG. 1 is that a plurality of variable light sources 1a, 1b, and 1c are provided, and a plurality of optical signals are multiplexed and transmitted. For example, in FIG. 4, the multiplexing / demultiplexing unit 4b has two groups of input ports (λ1, λ5, λ9 and λ2, λ6, λ10) and (λ3, λ7, λ11 and λ4, λ8, λ12), and (λ1 , Λ5, λ9 and λ3, λ7, λ11) and (λ2, λ6, λ10 and λ4, λ8, λ12) have two groups of output ports. In correspondence with FIG. 4, a plurality of outputs of (λ1, λ3), (λ2, λ4), (λ5, λ7), (λ6, λ8), (λ9, λ11), and (λ10, λ12) are output. Do.
In FIG. 5, a more general description is given, and the illustrated wavelength multiplexed signals from the two input ports are output to one of the two output ports depending on the included wavelength. This function is obtained by, for example, a waveguide type diffraction grating (AWG).

図４の構成図では示されていないが、図１の構成と同様に監視光源９ａ，９ｂと、監視モニタ１１ａ，１１ｂを備え、また中継地点と各受信端の光受信器８を使用して、送信端と中継地点間、及び中継地点と受信端間、の光伝送路の障害発生を監視できる。
この構成により、光伝送路の切替動作としては、各受信端にとっては図１の構成と同様、４通りの伝送路を選択できることになる。
この切替制御の詳細は、実施の形態１と同様なので、詳細記述を省略する。しかしいずれにしても、伝送路の切替を光信号の波長切替と合分波で行うので、分波の際にも光分岐と異なって原理的に光損失が発生しない。また機械的な切替でも無いので、信頼性が高い。こうした受動部品は構成部品として単純で低コストであり、故障率も低い。 Although not shown in the configuration diagram of FIG. 4, similarly to the configuration of FIG. 1, the monitoring light sources 9 a and 9 b and the monitoring monitors 11 a and 11 b are provided, and the relay point and the optical receiver 8 at each receiving end are used. It is possible to monitor the occurrence of a failure in the optical transmission path between the transmission end and the relay point and between the relay point and the reception end.
With this configuration, as the optical transmission path switching operation, four types of transmission paths can be selected for each receiving end as in the configuration of FIG.
The details of this switching control are the same as in the first embodiment, and thus detailed description thereof is omitted. However, in any case, since the switching of the transmission path is performed by switching the wavelength of the optical signal and multiplexing / demultiplexing, in principle, no optical loss occurs in the demultiplexing unlike the optical branching. Also, since there is no mechanical switching, the reliability is high. Such passive components are simple and low cost as components and have a low failure rate.

実施の形態３．
他の冗長光信号伝送装置及びシステムの構成を説明する。
図６は、本冗長光信号伝送装置及びシステムの構成を示す図である。また図７は、本実施の形態における光合分波器の詳細構成を示す図である。これらの図において図１の構成と異なることは、送信端では、可変光源１ｄの必要波長がλ１とλ２の２つでよいことと、この可変光源１ｄからの出力をまとめて、どちらかの合分波器１０ａ，１０ｂに切替える切替部１６としたことである。また中継地点では、合分波部４ｃの動作が後で説明するように少し異なる。なお、図６では、合波部４ｃ以降の経路振り分けが分かりやすいように、光伝送路３ｂ側を伝送した波長λ１’，λ２’と表記しているが、λ１とλ１’は等しく、λ２とλ２’は等しい。 Embodiment 3 FIG.
The configuration of another redundant optical signal transmission apparatus and system will be described.
FIG. 6 is a diagram showing the configuration of the redundant optical signal transmission device and system. FIG. 7 is a diagram showing a detailed configuration of the optical multiplexer / demultiplexer according to the present embodiment. 1 differs from the configuration of FIG. 1 in that the required wavelength of the variable light source 1d may be two at λ1 and λ2 at the transmission end, and the output from the variable light source 1d is combined to This is the switching unit 16 that switches to the duplexers 10a and 10b. At the relay point, the operation of the multiplexing / demultiplexing unit 4c is slightly different as will be described later. In FIG. 6, the wavelengths λ1 ′ and λ2 ′ transmitted on the optical transmission line 3b side are shown for easy understanding of the route assignment after the multiplexing unit 4c, but λ1 and λ1 ′ are equal, and λ2 λ2 ′ is equal.

この構成により、先ず送信端と中継地点間の光伝送路３ａ，３ｂの切替は、切替部１６のスイッチ動作で行われる。即ち可変光源１ｄからのλ１，λ２の光信号は、両方ともどちらかの光伝送路３ａまたは光伝送路３ｂに出力される。
中継地点の合分波部４ｃは、動作としては光伝送路３ａから入射したλ１，λ２の光信号をそれぞれ光伝送路５と光伝送路６に出力し、逆に光伝送路３ｂから入射したλ１，λ２の光信号をそれぞれ逆の光伝送路６と光伝送路５に入替えて出力する。
図７に示すように、合分波部４ｃは、光伝送路３ａを伝送した波長λ１の光信号を光伝送路５へ、波長λ２の光信号を光伝送路６へ出力し、光伝送路３ｂを伝送した波長λ１の光信号を光伝送路６へ、波長λ２の光信号を光伝送路５へ出力する。このような機能を持つ合分波部４ｃは、周回性導波路型回折格子（周回性ＡＷＧ）により得られる。
本実施の形態による光伝送システムの場合、送信端側で２つの波長と合分波部４ｃへの２つの入力経路（光伝送路３ａ，３ｂ）を切替えることにより、受信端までの４通りの経路を選択できるので、例えば、図６に示すように、光伝送路３ｂと光伝送路５に障害が発生した場合は、送信端から波長λ２の光信号で光伝送路３ａに出力することで光伝送路３ａ、合分波部４ｃ、光伝送路６を介して受信端まで光信号を伝送できる。更に、合分波部４ｃを特に制御することなく、それ以降の経路を決定できるので、中継地点での故障などの不具合を少なくでき、簡易な構成で信頼性の高い光伝送システムが得られる。 With this configuration, first, switching of the optical transmission paths 3 a and 3 b between the transmission end and the relay point is performed by the switching operation of the switching unit 16. That is, both the optical signals of λ1 and λ2 from the variable light source 1d are output to one of the optical transmission lines 3a or 3b.
The multiplexer / demultiplexer 4c at the relay point outputs the optical signals of λ1 and λ2 incident from the optical transmission path 3a to the optical transmission path 5 and the optical transmission path 6, respectively, and conversely enters from the optical transmission path 3b. The optical signals of λ1 and λ2 are switched to the opposite optical transmission lines 6 and 5, respectively, and output.
As shown in FIG. 7, the multiplexing / demultiplexing unit 4c outputs the optical signal having the wavelength λ1 transmitted through the optical transmission line 3a to the optical transmission line 5 and the optical signal having the wavelength λ2 to the optical transmission line 6, and The optical signal of wavelength λ1 transmitted through 3b is output to the optical transmission line 6, and the optical signal of wavelength λ2 is output to the optical transmission line 5. The multiplexing / demultiplexing unit 4c having such a function is obtained by a circular waveguide type diffraction grating (circular AWG).
In the case of the optical transmission system according to the present embodiment, four wavelengths up to the reception end are switched by switching the two wavelengths and the two input paths (optical transmission paths 3a and 3b) to the multiplexing / demultiplexing unit 4c on the transmission end side. Since a route can be selected, for example, as shown in FIG. 6, when a failure occurs in the optical transmission line 3b and the optical transmission line 5, an optical signal of wavelength λ2 is output from the transmission end to the optical transmission line 3a. An optical signal can be transmitted to the receiving end via the optical transmission line 3a, the multiplexing / demultiplexing unit 4c, and the optical transmission line 6. Further, since the subsequent route can be determined without particularly controlling the multiplexing / demultiplexing unit 4c, problems such as failure at the relay point can be reduced, and a highly reliable optical transmission system can be obtained with a simple configuration.

本実施の形態では、可変光源に求められる波長数が減少するため、波長資源を有効に活用でき、通信可能な装置数を倍増することができる。可変光源に求められる波長可変能力を限定できるため、装置コストを低減することができる。また、中継地点の合分波部は、外部からの複雑な切替制御などは必要としない単純で低コストな受動光素子であり、部品の故障率も低く信頼性が高い。   In the present embodiment, since the number of wavelengths required for the variable light source is reduced, wavelength resources can be used effectively, and the number of communicable devices can be doubled. Since the wavelength variable capability required for the variable light source can be limited, the apparatus cost can be reduced. The multiplexing / demultiplexing part at the relay point is a simple and low-cost passive optical element that does not require complicated switching control from the outside, and has a low component failure rate and high reliability.

実施の形態４．
他の冗長光信号伝送装置及びシステムの構成を説明する。
図８は、本冗長光信号伝送装置及びシステムの構成を示す図である。これらの図において図６の構成と異なるところは、送信端において可変光源に代えて固定波長の（光信号用）光源２１ａと光源２１ｂを用い、これらの出力を波長多重する合波部１７を使用する構成としたことである。
即ちこの図８の構成によれば、複数の固定波長λの光源２１ａ，２１ｂを合波して光伝送路３ａ，３ｂに出力する、冗長構成をとっている。従って装置としては安価な固定波長光源を使用でき、コストを低減できる。 Embodiment 4 FIG.
The configuration of another redundant optical signal transmission apparatus and system will be described.
FIG. 8 is a diagram showing the configuration of the redundant optical signal transmission device and system. 6 differs from the configuration of FIG. 6 in that a light source 21a and a light source 21b having fixed wavelengths are used instead of a variable light source at the transmission end, and a multiplexing unit 17 that wavelength-multiplexes these outputs is used. It is that it was set as the structure to do.
That is, according to the configuration of FIG. 8, a redundant configuration is adopted in which a plurality of light sources 21a and 21b having a fixed wavelength λ are combined and output to the optical transmission lines 3a and 3b. Therefore, an inexpensive fixed wavelength light source can be used as the apparatus, and the cost can be reduced.

切替部１６以降の動作は図６の構成と同様であるので、詳細記述は省略する。
本実施の形態では、一組の送信端と受信端について構成と動作を説明したが、他の実施の形態と同様に固定光源の数を増やして波長数を増やす構成もとれる。
また上記各実施の形態において、光受信器８と可変光源１や（固定）光源２１等を送信端と受信端に相互に設けることにより、双方向の光ネットワークを構成して、しかも光伝送路の障害が発生しても、通信が続行できる、冗長光信号伝送ネットワークが得られる。 Since the operation after the switching unit 16 is the same as that of the configuration in FIG.
In the present embodiment, the configuration and operation have been described for a pair of transmission end and reception end. However, as in the other embodiments, the number of wavelengths can be increased by increasing the number of fixed light sources.
In each of the above embodiments, the optical receiver 8, the variable light source 1, the (fixed) light source 21 and the like are provided at the transmission end and the reception end to form a bidirectional optical network, and the optical transmission line. Even if this failure occurs, a redundant optical signal transmission network can be obtained in which communication can continue.

ところで上記構成によれば、可変光源の切替や接続経路の切替を行う送信端において、監視光反射器１２ａを中継点に設けて、送信端から中継地点までの光伝送路の障害を検出できるので、中継地点に複雑な切替処理機能が必要無くなる。また単純な受動素子等で構成でき、信頼性が向上する効果もある。   By the way, according to the above configuration, since the monitoring light reflector 12a is provided at the relay point at the transmission end for switching the variable light source and the connection path, it is possible to detect a failure in the optical transmission path from the transmission end to the relay point. This eliminates the need for a complicated switching processing function at the relay point. Further, it can be configured with a simple passive element or the like, and has an effect of improving reliability.

上記各実施の形態では、切替制御部１３はハードウェアで構成されるとして説明したが、図３の動作フロー機能を持つソフトウェアで構成してもよい。即ち、図３の動作フローの各ステップで示される方法で切替制御をしてもよい。   In each of the above embodiments, the switching control unit 13 has been described as being configured by hardware, but may be configured by software having the operation flow function of FIG. That is, switching control may be performed by the method shown in each step of the operation flow in FIG.

この発明の実施の形態１における冗長光信号伝送装置及びシステムの構成を示す図である。It is a figure which shows the structure of the redundant optical signal transmission apparatus and system in Embodiment 1 of this invention. 実施の形態１における合分波部の詳細構成を示す図である。3 is a diagram illustrating a detailed configuration of an multiplexing / demultiplexing unit according to Embodiment 1. FIG. 実施の形態１における切替制御部の動作を示すフロー図である。FIG. 6 is a flowchart showing an operation of a switching control unit in the first embodiment. この発明の実施の形態２における冗長光信号伝送装置及びシステムの構成を示す図である。It is a figure which shows the structure of the redundant optical signal transmission apparatus and system in Embodiment 2 of this invention. 実施の形態２における合分波部の詳細構成を示す図である。FIG. 10 is a diagram illustrating a detailed configuration of a multiplexing / demultiplexing unit according to the second embodiment. この発明の実施の形態３における冗長光信号伝送装置及びシステムの構成を示す図である。It is a figure which shows the structure of the redundant optical signal transmission apparatus and system in Embodiment 3 of this invention. 実施の形態３における合分波部の詳細構成を示す図である。FIG. 10 is a diagram illustrating a detailed configuration of a multiplexing / demultiplexing unit according to Embodiment 3. 実施の形態４における冗長光信号伝送装置及びシステムの構成を示す図である。FIG. 10 is a diagram illustrating a configuration of a redundant optical signal transmission device and system according to a fourth embodiment. 従来の光伝送システムの構成を示す図である。It is a figure which shows the structure of the conventional optical transmission system.

符号の説明Explanation of symbols

１，１ａ，１ｂ，１ｃ 可変光源、２ 分波部、３ａ，３ｂ 光伝送路、４，４ｂ，４ｃ 合分波部、５，５ａ，５ｂ，５ｃ，６，６ａ，６ｂ，６ｃ 光伝送路、７，７ａ，７ｂ，７ｃ 合波部、８，８ａ，８ｂ，８ｃ 光受信器、９ａ，９ｂ 監視光源、１０ａ，１０ｂ 合分波器、１１ａ，１１ｂ 監視モニタ、１２ａ，１２ｂ 監視光反射器、１３ 切替制御部、１４ａ，１４ｂ 分波部、１５ａ，１５ｂ 合波部、１６ 切替部、１７ 合波部、２１ａ，２１ｂ （固定）光源。   1, 1a, 1b, 1c Variable light source, 2 demultiplexing unit, 3a, 3b optical transmission line, 4, 4b, 4c multiplexing / demultiplexing unit, 5, 5a, 5b, 5c, 6, 6a, 6b, 6c optical transmission line , 7, 7a, 7b, 7c multiplexer, 8, 8a, 8b, 8c optical receiver, 9a, 9b monitoring light source, 10a, 10b multiplexer / demultiplexer, 11a, 11b monitoring monitor, 12a, 12b monitoring light reflector , 13 switching control unit, 14a, 14b demultiplexing unit, 15a, 15b multiplexing unit, 16 switching unit, 17 multiplexing unit, 21a, 21b (fixed) light source.

Claims (6)

光伝送路に光信号を出力する送信端、前記送信端からの光信号を中継する光中継部、前記光中継部で中継された光信号を受信する受信端、前記光伝送路を監視して監視結果を出力する監視モニタ部を備えた光伝送システムであって、
前記光伝送路は、前記送信端と前記光中継部とに接続して光信号を伝送する複数の前半光伝送路と、前記光中継部と前記受信端とに接続して光信号を伝送する２以上の後半光伝送路とを有して前半／後半でそれぞれ冗長化されており、
前記送信端は、前記監視結果に応じて前記複数の前半光伝送路のうち該当する前半光伝送路に該当する波長の光信号を出力し、
前記光中継部は、前記複数の前半光伝送路毎に伝送されてきた光信号の波長に応じてその光信号の出力先の前記後半光伝送路が予め決められている
ことを特徴とする光伝送システム。 Monitor the transmitting end for outputting the optical signal to the optical transmission line, the optical repeater for relaying the optical signal from the transmitting end, the receiving end for receiving the optical signal relayed by the optical repeater, and the optical transmission line An optical transmission system including a monitoring monitor unit that outputs a monitoring result,
The optical transmission path is connected to the transmitting end and the optical repeater to transmit an optical signal, and is connected to the optical repeater and the receiving end to transmit an optical signal. It has two or more second half optical transmission lines and is made redundant in the first half / second half,
The transmitting end outputs an optical signal having a wavelength corresponding to a corresponding first half optical transmission path among the plurality of first half optical transmission paths according to the monitoring result,
In the optical repeater, the latter optical transmission path to which the optical signal is output is determined in advance according to the wavelength of the optical signal transmitted for each of the plurality of first optical transmission lines. Transmission system. 送信端は、異なる波長の光信号を出力可能な可変光源部、監視結果に応じて前記可変光源部が出力する光信号の波長を切替える切替え制御部、前記可変光源部からの光信号の波長に応じて出力先の前半光伝送路を予め定められた経路選択部を有する
ことを特徴とする請求項１記載の光伝送システム。 The transmission end is a variable light source unit that can output optical signals of different wavelengths, a switching control unit that switches the wavelength of the optical signal output by the variable light source unit according to the monitoring result, and the wavelength of the optical signal from the variable light source unit. The optical transmission system according to claim 1, further comprising a path selection unit that predetermines the first half optical transmission path as an output destination. 送信端は、異なる波長の光信号を出力可能な可変光源部、切替え制御信号に基づき前記可変光源部からの光信号を前半光伝送路に切替え出力する経路選択部、監視結果に応じて前記可変光源部が出力する光信号の波長を切替え、かつ前記切替え制御信号を出力する切替え制御部とを有する
ことを特徴とする請求項１記載の光伝送システム。 The transmission end is a variable light source unit that can output optical signals of different wavelengths, a path selection unit that switches and outputs the optical signal from the variable light source unit to the first half optical transmission line based on the switching control signal, and the variable according to the monitoring result. The optical transmission system according to claim 1, further comprising: a switching control unit that switches a wavelength of an optical signal output from the light source unit and outputs the switching control signal. 送信端は、互いに異なる波長の光信号を出力する複数の光源部、前記複数の光源部からの複数の光信号を多重化しかつ切替え制御信号に基づき多重化した光信号を前半光伝送路に切替え出力する経路選択部、監視結果に応じて前記切替え制御信号を出力する切替え制御部とを有し、
光中継部は、前記前半光伝送路からの多重化光信号を分離し、前記前半光伝送路及び分離後の光信号の波長に応じて予め定められた後半光伝送路に当該光信号を出力する
ことを特徴とする請求項１記載の光伝送システム。 The transmission end is a plurality of light source units that output optical signals of different wavelengths, and a plurality of optical signals from the plurality of light source units are multiplexed and the multiplexed optical signal is switched to the first half optical transmission line based on the switching control signal A route selection unit for outputting, a switching control unit for outputting the switching control signal according to the monitoring result,
The optical repeater separates the multiplexed optical signal from the first half optical transmission line and outputs the optical signal to the second half optical transmission line predetermined according to the wavelength of the first half optical transmission line and the separated optical signal The optical transmission system according to claim 1. 光中継部は、監視光を折り返して戻り光とする反射器を光伝送路それぞれに対応して設け、
送信端は、前記監視光を出力する監視光源部、前記監視光を光伝送路に合波するとともに前記戻り光を監視モニタ部に出力する合分波部を有し、
前記監視モニタ部は、前記戻り光の有無に基づき監視結果を出力する
ことを特徴とする請求項１〜４のいずれか記載の光伝送システム。 The optical repeater is provided with a reflector for returning the monitoring light to return light corresponding to each optical transmission line,
The transmission end includes a monitoring light source unit that outputs the monitoring light, a multiplexing / demultiplexing unit that multiplexes the monitoring light to an optical transmission line and outputs the return light to the monitoring monitor unit,
The optical transmission system according to claim 1, wherein the monitoring monitor unit outputs a monitoring result based on the presence or absence of the return light. 送信端は、互いに異なる波長の光信号を出力可能な所定数の可変光源部、監視結果に応じて前記所定数の可変光源部が出力する光信号の波長を切替え可能な切替え制御部、予め複数の前半光伝送路毎に出力する波長を定められかつ前記所定数の可変光源部からの所定数の光信号を当該前半光伝送路に多重化して出力する経路選択部を有する
ことを特徴とする請求項１記載の光伝送システム。 The transmission end includes a predetermined number of variable light source units capable of outputting optical signals having different wavelengths, a switching control unit capable of switching the wavelengths of the optical signals output from the predetermined number of variable light source units according to a monitoring result, And a path selector that multiplexes and outputs a predetermined number of optical signals from the predetermined number of variable light source units to the first half optical transmission line. The optical transmission system according to claim 1.

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