JP6339401B2 - Mode multiplexing transmission optical transmitter and optical communication system - Google Patents

Mode multiplexing transmission optical transmitter and optical communication system Download PDF

Info

Publication number
JP6339401B2
JP6339401B2 JP2014073623A JP2014073623A JP6339401B2 JP 6339401 B2 JP6339401 B2 JP 6339401B2 JP 2014073623 A JP2014073623 A JP 2014073623A JP 2014073623 A JP2014073623 A JP 2014073623A JP 6339401 B2 JP6339401 B2 JP 6339401B2
Authority
JP
Japan
Prior art keywords
propagation
wavelength
mode
transmission
optical
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 - Fee Related
Application number
JP2014073623A
Other languages
Japanese (ja)
Other versions
JP2015198262A5 (en
JP2015198262A (en
Inventor
森田　逸郎
逸郎 森田
釣谷　剛宏
剛宏 釣谷
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.)
KDDI Corp
Original Assignee
KDDI 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 KDDI Corp filed Critical KDDI Corp
Priority to JP2014073623A priority Critical patent/JP6339401B2/en
Publication of JP2015198262A publication Critical patent/JP2015198262A/en
Publication of JP2015198262A5 publication Critical patent/JP2015198262A5/ja
Application granted granted Critical
Publication of JP6339401B2 publication Critical patent/JP6339401B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Optical Communication System (AREA)

Description

本発明は、モード多重伝送による光通信技術に関する。   The present invention relates to an optical communication technique using mode multiplexing transmission.

光ファイバによる伝送容量を増加させるために、非特許文献１は、同じ波長の信号を複数のモードで伝搬させ、各モードで伝搬する信号には独立した情報を搬送させるモード多重伝送を開示している。   In order to increase the transmission capacity by optical fiber, Non-Patent Document 1 discloses mode multiplex transmission in which signals of the same wavelength are propagated in a plurality of modes, and independent information is conveyed to the signals propagated in each mode. Yes.

Ｒ．Ｒｙｆ，ｅｔ ａｌ．，"Ｓｐａｃｅ−ｄｉｖｉｓｉｏｎ ｍｕｌｔｉｐｌｅｘｉｎｇ ｏｖｅｒ １０ｋｍ ｏｆ ｔｈｒｅｅ−ｍｏｄｅ ｆｉｂｅｒ ｕｓｉｎｇ ｃｏｈｅｒｅｎｔ ６ｘ６ ＭＩＭＯ ｐｒｏｃｅｓｓｉｎｇ"、ＯＳＡ／ＯＦＣ／ＮＦＯＥＣ ２０１１， Ｐｏｓｔｄｅａｄｌｉｎｅ Ｐａｐｅｒｓ ２０１１年R. Ryf, et al. , “Space-division multiplexing over 10 km of three-mode fiber using coherent 6 × 6 MIMO processing”, OSA / OFC / NFECEC 2011, Postdeline Papers 2011

一般的なマルチモードファイバではモード間結合が生じる。モード間結合が生じた場合、各モードで伝搬する信号の独立性が維持できなくなるため、モード多重伝送による伝送容量拡大ができない。モード間結合を小さくするために、特別に設計したマルチモードファイバ、モード合波器及びモード分波器を使用することが考えられる。しかしながら、ファイバ接続時のわずかな位置ずれや、モード合波器やモード分波器の設計値からのずれ等がモード結合を誘発するため、モード結合を十分に小さくすることは一般的には難しい。このため、各受信機において、無線通信システムで用いられているＭＩＭＯ伝送と同様のデジタル信号処理を用いることでモード分離を行う構成が非特許文献１には開示されているが、モード数が多くなるに従い、信号処理に必要となる回路規模が莫大となり、その実現が困難となる。   In a general multimode fiber, coupling between modes occurs. When coupling between modes occurs, the independence of signals propagating in each mode cannot be maintained, and thus the transmission capacity cannot be increased by mode multiplexing transmission. In order to reduce the coupling between modes, it is conceivable to use a specially designed multimode fiber, a mode multiplexer and a mode duplexer. However, it is generally difficult to make the mode coupling sufficiently small because a slight positional deviation at the time of fiber connection or a deviation from the design value of the mode multiplexer or mode demultiplexer induces mode coupling. . For this reason, a configuration for performing mode separation by using digital signal processing similar to MIMO transmission used in a wireless communication system in each receiver is disclosed in Non-Patent Document 1, but the number of modes is large. Accordingly, the circuit scale required for signal processing becomes enormous and it becomes difficult to realize it.

本発明は、効果的にモード間結合の影響を抑圧できる、モード多重伝送の光送信装置及び光通信システムを提供するものである。   The present invention provides an optical transmission apparatus and an optical communication system for mode multiplexing transmission that can effectively suppress the influence of inter-mode coupling.

本発明の一側面によると、モード多重伝送のための光送信装置は、各伝搬モードのそれぞれに対応する複数の送信手段であって、それぞれが波長多重信号を出力する前記複数の送信手段と、送信手段により出力される波長多重信号が、当該送信手段に対応する伝搬モードで伝搬される様にマルチモードファイバに出力するガイド手段と、を備えており、送信手段が出力する波長多重信号に含まれる波長は、当該送信手段に対応する伝搬モードとの伝搬定数の差が所定値以内である他の伝搬モードに対応する送信手段が出力する波長多重信号には含まれない、ことを特徴とする。 According to one aspect of the present invention, an optical transmission device for mode multiplexing transmission is a plurality of transmission units corresponding to each of the propagation modes, each of the plurality of transmission units outputting a wavelength multiplexed signal; wavelength-multiplexed signal outputted by the transmitting means, and guide means for outputting the multimode fiber as propagated by the propagation mode corresponding to the transmission means comprises a, included in the wavelength multiplexed signal output by the transmitting means The wavelength to be transmitted is not included in the wavelength multiplexed signal output from the transmission unit corresponding to another propagation mode whose propagation constant difference with the transmission mode corresponding to the transmission unit is within a predetermined value. .

モード間結合の影響を抑圧できる。   The influence of mode coupling can be suppressed.

伝搬モードの説明図。Explanatory drawing of a propagation mode. 一実施形態によるモード多重伝送を行う光通信システムの構成図。1 is a configuration diagram of an optical communication system that performs mode multiplexing transmission according to an embodiment. FIG. 一実施形態による波長配置を示す図。The figure which shows the wavelength arrangement | positioning by one Embodiment.

以下、本発明の例示的な実施形態について図面を参照して説明する。なお、以下の各図においては、実施形態の説明に必要ではない構成要素については図から省略する。   Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. In the following drawings, components that are not necessary for the description of the embodiments are omitted from the drawings.

図１は、伝搬モードについて説明する図である。マルチモードファイバを伝搬するモード数は、導波路パラメータ（規格化周波数）によって変化する。ここで、ある伝搬モードの伝搬定数と異なる伝搬定数の伝搬モードは、異なる伝搬モードである。なお、図１の規格化周波数が示す波長範囲は大変広く、波長多重で使用する複数の波長は、図１の横軸のスケールにおいては略点で表される。例えば、図１において規格化周波数が４の波長付近においては、伝搬定数の異なる３つの伝搬モードが存在する。   FIG. 1 is a diagram illustrating the propagation mode. The number of modes propagating through the multimode fiber varies depending on the waveguide parameter (normalized frequency). Here, a propagation mode having a propagation constant different from that of a certain propagation mode is a different propagation mode. Note that the wavelength range indicated by the normalized frequency in FIG. 1 is very wide, and a plurality of wavelengths used in wavelength multiplexing are represented by points on the horizontal axis in FIG. For example, in FIG. 1, there are three propagation modes having different propagation constants in the vicinity of a wavelength having a normalized frequency of 4.

図２は、本実施形態による光通信システムの構成図である。光送信装置１は、マルチモードファイバ３の各伝搬モードに対応する送信部１１−１〜１１−Ｋを備えている。各送信部１１−１〜１１−Ｋは、対応する伝搬モードで使用する波長の光信号を送信データで変調し、波長多重してモード合波部１２に出力する。なお、各伝搬モードで使用する波長の考え方については後述する。モード合波部１２は、各送信部１１−１〜１１−Ｋからの波長多重された光信号が、対応するモードでマルチモードファイバ３を伝搬する様に、波長多重された光信号をマルチモードファイバ３に出力する導材（ガイド部）である。   FIG. 2 is a configuration diagram of the optical communication system according to the present embodiment. The optical transmission device 1 includes transmission units 11-1 to 11 -K corresponding to the propagation modes of the multimode fiber 3. Each of the transmission units 11-1 to 11 -K modulates an optical signal having a wavelength used in the corresponding propagation mode with transmission data, multiplexes the wavelength, and outputs the result to the mode multiplexing unit 12. The concept of the wavelength used in each propagation mode will be described later. The mode multiplexer 12 converts the wavelength-multiplexed optical signal into the multimode so that the wavelength-multiplexed optical signals from the transmitters 11-1 to 11-K propagate through the multimode fiber 3 in the corresponding mode. A conductive material (guide portion) that outputs to the fiber 3.

光受信装置２のモード分波部２２は、マルチモードファイバ３の各モードで伝搬する光信号を対応する受信部に入力させるための導材である。各受信部２１−１〜２１−Ｋは、対応する伝搬モードでマルチモードファイバ３を伝搬した光信号を波長分離し、各波長の光信号を復調する。   The mode demultiplexing unit 22 of the optical receiver 2 is a conducting material for inputting an optical signal propagating in each mode of the multimode fiber 3 to the corresponding receiving unit. Each receiving unit 21-1 to 21 -K demultiplexes the optical signal propagated through the multimode fiber 3 in the corresponding propagation mode, and demodulates the optical signal of each wavelength.

続いて、本実施形態による、各伝搬モードで使用する波長配置について説明する。まず、本実施形態では、ある伝搬モードの伝搬定数と、その差が所定値以内である伝搬定数の伝搬モードを特定する。例えば、図３においてモード＃Ｂ及び＃Ｃの伝搬定数は、モード＃Ａの伝搬定数との差が所定値以内であるものとする。一実施形態において、モード＃Ａで伝搬させる波長は、モード＃Ｂ及び＃Ｃでは伝搬させない。この様に、伝搬定数が所定値以内のモードにおいては互いに異なる波長のみを伝搬させることでモード間結合が発生した場合においても、受信部２１−１〜２１−Ｋに具備される、帯域通過型光フィルタにより、その信号特性への影響を低減させることができる。   Next, the wavelength arrangement used in each propagation mode according to the present embodiment will be described. First, in this embodiment, a propagation constant of a certain propagation mode and a propagation mode of a propagation constant whose difference is within a predetermined value are specified. For example, in FIG. 3, it is assumed that the propagation constants of modes #B and #C have a difference from the propagation constant of mode #A within a predetermined value. In one embodiment, the wavelengths propagated in mode #A are not propagated in modes #B and #C. As described above, in the mode in which the propagation constant is within the predetermined value, even when the coupling between the modes is generated by propagating only different wavelengths, the band-pass type provided in the receiving units 21-1 to 21-K. The influence on the signal characteristics can be reduced by the optical filter.

また、他の実施形態として、伝搬定数が、ある伝搬モードの伝搬定数より大きく、かつ、最も近い伝搬モードを第１の伝搬モードとし、伝搬定数が、ある伝搬モードの伝搬定数より小さく、かつ、最も近い伝搬モードを第２の伝搬モードとし、これら第１の伝搬モード及び第２の伝搬モードを、纏めて、当該ある伝搬モードの隣接伝搬モードとする。そして、ある伝搬モードで使用する波長は、隣接伝搬モードで使用する波長とは互いに異なる様にする。この様に構成することで、モード間結合の影響を低減させることができる。   As another embodiment, the propagation constant is larger than the propagation constant of a certain propagation mode, the closest propagation mode is the first propagation mode, the propagation constant is smaller than the propagation constant of a certain propagation mode, and The closest propagation mode is defined as a second propagation mode, and the first propagation mode and the second propagation mode are collectively defined as an adjacent propagation mode of the certain propagation mode. The wavelength used in a certain propagation mode is set to be different from the wavelength used in the adjacent propagation mode. By comprising in this way, the influence of the coupling between modes can be reduced.

なお、モード多重伝送において使用される波長は、所定の波長間隔の波長グリッドに対応する波長である。つまり、送信部１１−１〜１１−Ｋが使用する波長は、異なる波長グリッドに対応する波長である。   Note that the wavelength used in the mode multiplexing transmission is a wavelength corresponding to a wavelength grid having a predetermined wavelength interval. That is, the wavelengths used by the transmission units 11-1 to 11-K are wavelengths corresponding to different wavelength grids.

Claims (4)

モード多重伝送のための光送信装置であって、
各伝搬モードのそれぞれに対応する複数の送信手段であって、それぞれが波長多重信号を出力する前記複数の送信手段と、
送信手段により出力される波長多重信号が、当該送信手段に対応する伝搬モードで伝搬される様にマルチモードファイバに出力するガイド手段と、
を備えており、
送信手段が出力する波長多重信号に含まれる波長は、当該送信手段に対応する伝搬モードとの伝搬定数の差が所定値以内である他の伝搬モードに対応する送信手段が出力する波長多重信号には含まれない、ことを特徴とする光送信装置。 An optical transmitter for mode multiplexing transmission,
A plurality of transmission means corresponding to each of the propagation modes, each of the plurality of transmission means outputting a wavelength multiplexed signal;
Guide means for outputting to the multimode fiber so that the wavelength multiplexed signal output by the transmission means is propagated in the propagation mode corresponding to the transmission means;
With
Wavelength included in the wavelength-multiplexed signal transmitting means is output to the wavelength multiplexing signal difference in propagation constant between the propagation modes corresponding to the transmission means outputs the transmission means corresponding to the other mode of propagation is within a predetermined value Is not included , an optical transmission device characterized by that. モード多重伝送のための光送信装置であって、
各伝搬モードのそれぞれに対応する送信手段と、
送信手段により出力される波長多重信号が、当該送信手段に対応する伝搬モードで伝搬される様にマルチモードファイバに出力するガイド手段と、
を備えており、
送信手段は、当該送信手段に対応する伝搬モードの伝搬定数より大きく、かつ、最も近い伝搬定数の伝搬モードに対応する第１の送信手段、及び、当該送信手段に対応する伝搬モードの伝搬定数より小さく、かつ、最も近い伝搬定数の伝搬モードに対応する第２の送信手段のそれぞれとは互いに異なる波長を使用することを特徴とする光送信装置。 An optical transmitter for mode multiplexing transmission,
Transmission means corresponding to each of the propagation modes;
Guide means for outputting to the multimode fiber so that the wavelength multiplexed signal output by the transmission means is propagated in the propagation mode corresponding to the transmission means;
With
The transmission means is larger than the propagation constant of the propagation mode corresponding to the transmission means and the first transmission means corresponding to the propagation mode of the closest propagation constant, and the propagation constant of the propagation mode corresponding to the transmission means. An optical transmission apparatus using a wavelength different from each of the second transmission means corresponding to a propagation mode having a small and closest propagation constant. 前記モード多重伝送において使用される波長は、所定の波長間隔の波長グリッドに対応する波長であり、
前記マルチモードファイバの異なる伝搬モードのそれぞれに対応する送信手段において使用される波長は、異なる波長グリッドに対応する波長であることを特徴とする請求項１又は２に記載の光送信装置。 The wavelength used in the mode multiplex transmission is a wavelength corresponding to a wavelength grid of a predetermined wavelength interval,
3. The optical transmission device according to claim 1, wherein wavelengths used in transmission units corresponding to different propagation modes of the multimode fiber are wavelengths corresponding to different wavelength grids. 4. 請求項１から３のいずれか１項に記載の光送信装置と、前記光送信装置と前記マルチモードファイバ経由で通信する光受信装置と、を含む光通信システムであって、
前記光受信装置は、
前記各伝搬モードのそれぞれに対応し、対応する伝搬モードの波長多重信号を受信する受信手段を備えており、
前記受信手段は、対応する伝搬モードの波長を選択する光フィルタを有することを特徴とする光通信システム。 An optical communication system comprising: the optical transmission device according to any one of claims 1 to 3; and an optical reception device that communicates with the optical transmission device via the multimode fiber,
The optical receiver is
Corresponding to each of the propagation modes, comprising a receiving means for receiving a wavelength-division multiplexed signal of the corresponding propagation mode,
The optical communication system, wherein the receiving means includes an optical filter for selecting a wavelength of a corresponding propagation mode.
JP2014073623A 2014-03-31 2014-03-31 Mode multiplexing transmission optical transmitter and optical communication system Expired - Fee Related JP6339401B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2014073623A JP6339401B2 (en) 2014-03-31 2014-03-31 Mode multiplexing transmission optical transmitter and optical communication system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2014073623A JP6339401B2 (en) 2014-03-31 2014-03-31 Mode multiplexing transmission optical transmitter and optical communication system

Publications (3)

Publication Number Publication Date
JP2015198262A JP2015198262A (en) 2015-11-09
JP2015198262A5 JP2015198262A5 (en) 2016-09-08
JP6339401B2 true JP6339401B2 (en) 2018-06-06

Family

ID=54547761

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2014073623A Expired - Fee Related JP6339401B2 (en) 2014-03-31 2014-03-31 Mode multiplexing transmission optical transmitter and optical communication system

Country Status (1)

Country Link
JP (1) JP6339401B2 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3457186B1 (en) * 2016-06-16 2022-10-26 Nippon Telegraph and Telephone Corporation An optical transmission system
JP2018006474A (en) * 2016-06-29 2018-01-11 日本電信電話株式会社 Optical fiber communication system
JP6621067B2 (en) * 2016-12-08 2019-12-18 日本電信電話株式会社 Optical transmission system and optical transmission method

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102009025232A1 (en) * 2009-06-13 2010-12-16 Technische Universität Dortmund Method and device for transmitting optical information between transmitter station and receiver station via a multimode optical waveguide
EP2446560A1 (en) * 2009-06-26 2012-05-02 Alcatel Lucent Receiver for optical transverse-mode-multiplexed signals
JP5753112B2 (en) * 2012-02-23 2015-07-22 日本電信電話株式会社 Multimode optical transmission system and multimode optical transmission method

Also Published As

Publication number Publication date
JP2015198262A (en) 2015-11-09

Similar Documents

Publication Publication Date Title
JP7074152B2 (en) Optical communication device, optical transmission system, and optical communication method
CN103095373A (en) Self-correlation optical fiber communication system based on mode division multiplexing
JP2020522748A5 (en)
KR20150012131A (en) Optical transmitter, receiver, and transmission system based on multi-mode fiber
ATE322775T1 (en) NETWORK TRANSMITTER/RECEIVER FOR EXPANDING THE BANDWIDTH OF A FIBER OPTIC BASED NETWORK INFRASTRUCTURE
EP2907250B1 (en) Optical communication system, method of bi-directional communication and method of operating a network element
JP6339401B2 (en) Mode multiplexing transmission optical transmitter and optical communication system
JP2016163274A (en) Optical transmitter and optical transmission system
JP6339894B2 (en) Optical transmission system and mode multiplexer
JP2019154004A (en) Optical transmission system and optical transmission method
JPWO2018193835A1 (en) Bidirectional optical transmission system and bidirectional optical transmission method
JP5910750B2 (en) Optical branch coupling device and optical branch coupling method
JPWO2016051774A1 (en) Node device and control method of node device
CN112929123A (en) Optical transmission system, method and optical communication system
JP6297139B2 (en) Optical ring network
US11115146B2 (en) Optical signal demultiplexing device, optical signal reception device, and optical signal demultiplexing method
WO2020116013A1 (en) Relay device for space division multiplex optical fiber, optical transmission device and optical reception device
JP2010109872A (en) Degree extension method and optical hub node device
JP7306466B2 (en) Optical communication system, optical communication device, optical communication method and program
JP2015198262A5 (en)
US20120063719A1 (en) DWDM and CWDM Communication System over Multimode Fiber
JP2015162805A (en) Multi-core optical fiber optical transmitter
JP5995296B2 (en) Optical receiver, multi-core optical fiber, and optical transmission system
KR101976965B1 (en) Optical add/drop multiplexer and optical network signal transmission method
JP2015039110A (en) Transmission device

Legal Events

Date Code Title Description
A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20160714

A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20160714

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20170612

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20170707

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20170724

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20180119

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20180129

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20180427

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20180510

R150 Certificate of patent or registration of utility model

Ref document number: 6339401

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

LAPS Cancellation because of no payment of annual fees