IEC TR 61292-6-2010 Optical amplifiers - Part 6 Distributed Raman amplification《光学放大器.第6部分 分布式拉曼放大器》.pdf

《IEC TR 61292-6-2010 Optical amplifiers - Part 6 Distributed Raman amplification《光学放大器.第6部分 分布式拉曼放大器》.pdf》由会员分享，可在线阅读，更多相关《IEC TR 61292-6-2010 Optical amplifiers - Part 6 Distributed Raman amplification《光学放大器.第6部分 分布式拉曼放大器》.pdf（30页珍藏版）》请在麦多课文档分享上搜索。

1、 IEC/TR 61292-6 Edition 1.0 2010-02 TECHNICAL REPORT Optical amplifiers Part 6: Distributed Raman amplification IEC/TR 61292-6:2010(E) THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2010 IEC, Geneva, Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be r

2、eproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or IECs member National Committee in the country of the requester. If you have any questions about IEC copyright or have an enquiry about o

3、btaining additional rights to this publication, please contact the address below or your local IEC member National Committee for further information. Droits de reproduction rservs. Sauf indication contraire, aucune partie de cette publication ne peut tre reproduite ni utilise sous quelque forme que

4、ce soit et par aucun procd, lectronique ou mcanique, y compris la photocopie et les microfilms, sans laccord crit de la CEI ou du Comit national de la CEI du pays du demandeur. Si vous avez des questions sur le copyright de la CEI ou si vous dsirez obtenir des droits supplmentaires sur cette publica

5、tion, utilisez les coordonnes ci-aprs ou contactez le Comit national de la CEI de votre pays de rsidence. IEC Central Office 3, rue de Varemb CH-1211 Geneva 20 Switzerland Email: inmailiec.ch Web: www.iec.ch About IEC publications The technical content of IEC publications is kept under constant revi

6、ew by the IEC. Please make sure that you have the latest edition, a corrigenda or an amendment might have been published. Catalogue of IEC publications: www.iec.ch/searchpub The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,). It al

7、so gives information on projects, withdrawn and replaced publications. IEC Just Published: www.iec.ch/online_news/justpub Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available on-line and also by email. Electropedia: www.electroped

8、ia.org The worlds leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical Vocabulary online. Customer Service Centre: www.iec.

9、ch/webstore/custserv If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service Centre FAQ or contact us: Email: csciec.ch Tel.: +41 22 919 02 11 Fax: +41 22 919 03 00 IEC/TR 61292-6 Edition 1.0 2010-02 TECHNICAL REPORT Optical amplifiers P

10、art 6: Distributed Raman amplification INTERNATIONAL ELECTROTECHNICAL COMMISSION T ICS 33.160.10; 33.180.30 PRICE CODE ISBN 2-8318-1081-7 Registered trademark of the International Electrotechnical Commission 2 TR 61292-6 IEC:2010(E) CONTENTS FOREWORD.4 INTRODUCTION.6 1 Scope.7 2 Normative references

11、7 3 Abbreviated terms.8 4 Background 8 4.1 General .8 4.2 Raman amplification process .8 4.3 Distributed vs. lumped amplification.10 4.4 Tailoring the Raman gain spectrum10 4.5 Forward and backward pumping configuration11 4.6 Typical performance of DRA 12 5 Applications of distributed Raman amplific

12、ation.13 5.1 General .13 5.2 All-Raman systems13 5.3 Hybrid EDFA Raman systems 14 5.3.1 Long repeaterless links 14 5.3.2 Long span masking in multi-span links .15 5.3.3 High capacity long haul and ultra-long haul systems.15 6 Performance characteristics and test methods 15 6.1 General .15 6.2 Perfor

13、mance of the Raman pump module 16 6.2.1 Pump wavelengths.16 6.2.2 Pump output power16 6.2.3 Pump degree-of-polarization (DOP)17 6.2.4 Pump relative intensity noise (RIN) 17 6.2.5 Insertion loss .17 6.2.6 Other passive characteristics .18 6.3 System level performance18 6.3.1 On-off signal gain 18 6.3

14、.2 Gain flatness .19 6.3.3 Polarization dependant gain (PDG) 20 6.3.4 Equivalent noise figure.20 6.3.5 Multi-path interference (MPI)20 7 Operational issues21 7.1 General .21 7.2 Dependence of Raman gain on transmission fibre21 7.3 Fibre line quality 22 7.4 High pump power issues22 7.4.1 Laser safety

15、.23 7.4.2 Damage to the fibre line.23 8 Conclusions24 Bibliography25 TR 61292-6 IEC:2010(E) 3 Figure 1 Stimulated Raman scattering process (left) and Raman gain spectrum for silica fibres (right) .9 Figure 2 Distributed vs. lumped amplification10 Figure 3 The use of multiple pump wavelengths to achi

16、eve flat broadband gain.11 Figure 4 Simulation results showing pump and signal propagation along an SMF span in forward (right plot) and backward (left plot) pumping configurations .11 Figure 5 On-off gain and equivalent NF for SMF using a dual pump backward DRA with pumps at 1 424 nm and 1 452 nm 1

17、3 Figure 6 Typical configuration of an amplification site in an all-Raman system 14 Figure 7 Typical configuration of a Raman pump module used for counter-propagating DRA16 Figure 8 Model for signal insertion loss (IL) of a Raman pump module used for counter-propagating DRA18 Figure 9 Typical config

18、uration used to measure on of gain (a) for co-propagating DRA and (b) for counter-propagating DRA.19 Figure 10 Variations of Raman on-off gain for different transmission fibres .22 4 TR 61292-6 IEC:2010(E) INTERNATIONAL ELECTROTECHNICAL COMMISSION _ OPTICAL AMPLIFIERS Part 6: Distributed Raman ampli

19、fication FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardizati

20、on in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is en

21、trusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non- governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the Int

22、ernational Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects sinc

23、e each technical committee has representation from all interested IEC National Committees. 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content

24、of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible i

25、n their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity as

26、sessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any services carried out by independent certification bodies. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, em

27、ployees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of

28、the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications. 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9) Attention is drawn to th

29、e possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. The main task of IEC technical committees is to prepare International Standards. However, a technical committee may pr

30、opose the publication of a technical report when it has collected data of a different kind from that which is normally published as an International Standard, for example “state of the art“. IEC 61292-6, which is a technical report, has been prepared by subcommittee 86C: Fibre optic systems and acti

31、ve devices, of IEC technical committee 86: Fibre optics. The text of this technical report is based on the following documents: Enquiry draft Report on voting 86C/910/DTR 86C/936/RVC Full information on the voting for the approval of this technical report can be found in the report on voting indicat

32、ed in the above table. TR 61292-6 IEC:2010(E) 5 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2. A list of all parts of the IEC 61292 series, published under the general title Optical amplifiers, can be found on the IEC website. The committee has decided that the

33、contents of this amendment and the base publication will remain unchanged until the stability date indicated on the IEC web site under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication will be reconfirmed, withdrawn, replaced by a revised edition,

34、 or amended. A bilingual version of this publication may be issued at a later date. IMPORTANT The colour inside logo on the cover page of this publication indicates that it contains colours which are considered to be useful for the correct understanding of its contents. Users should therefore print

35、this document using a colour printer. 6 TR 61292-6 IEC:2010(E) INTRODUCTION Distributed Raman amplification (DRA) describes the process whereby Raman pump power is introduced into the transmission fibre, leading to signal amplification within the transmission fibre though stimulated Raman scattering

36、. This technology has become increasingly widespread in recent years due to the many advantage that it offers optical system designers, including improved system optical signal-to-noise ratio (OSNR), and the ability to tailor the gain spectrum to cover any or several transmission bands. A fundamenta

37、l difference between distributed Raman amplification and amplification using discrete amplifiers, such as erbium-doped fibre amplifiers (EDFAs), is that the latter can be described using a black box approach, while the former is an inherent part of the system in which it is deployed. Thus, a discret

38、e amplifier is a unique and separate element with a well defined input and output ports, allowing rigorous specifications of the amplifiers performance characteristics and the methods used to test these characteristics. On the other hand, a distributed Raman amplifier is basically a pump module, wit

39、h the actual amplification process taking place along the transmission fibre. This means that many of the performance characteristics of distributed Raman amplification are inherently coupled to the system in which it is deployed. This technical report provides an overview of DRA and its application

40、s. It also provides a detailed discussion of the various performance characteristics related to DRA, some of the methods that can be used to test these characteristics, and some of the operational issues related to the distributed nature of the amplification process, such as the sensitivity to trans

41、mission line quality and eye-safety. The material provided is intended to provide a basis for future development of specifications and test method standards related to DRA. TR 61292-6 IEC:2010(E) 7 OPTICAL AMPLIFIERS Part 6: Distributed Raman amplification 1 Scope This part of IEC 61292, which is a

42、technical report, deals with distributed Raman amplification (DRA). The main purpose of the report is to provide background material for future standards (specifications, test methods and operating procedures) relating to DRA. The report covers the following aspects: general overview of Raman amplif

43、ication; applications of DRA; performance characteristics and test methods related to DRA; operational issues relating to the deployment of DRA. As DRA is a relatively young technology, and still rapidly evolving, some of the material in this report may become obsolete or irrelevant in a relatively

44、short period. This technical report will be frequently updated in order to minimize this possibility. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the la

45、test edition of the referenced document (including any amendments) applies. IEC 60825-2, Safety of laser products Part 2: Safety of optical fibre communication systems (OFCS) IEC 61290-3, Optical amplifiers Test methods Part 3: Noise figure parameters IEC 61290-3-1, Optical amplifiers Test methods P

46、art 3-1: Noise figure parameters Optical spectrum analyzer method IEC 61290-3-2, Optical amplifiers Test methods Part 3-2: Noise figure parameters Electrical spectrum analyzer method IEC 61290-7-1, Optical amplifiers Test methods Part 7-1: Out-of-band insertion losses Filtered optical power meter me

47、thod IEC 61291-1, Optical amplifiers Part 1: Generic specification IEC/TR 61292-3, Optical amplifiers Part 3: Classification, characteristics and applications IEC/TR 61292-4, Optical amplifiers Part 4: Maximum permissible optical power for the damage-free and safe use of optical amplifiers, includin

48、g Raman amplifiers ITU-T G.664, Optical safety procedures and requirements for optical transport systems ITU-T G.665, Generic characteristics of Raman amplifiers and Raman amplified subsystems 8 TR 61292-6 IEC:2010(E) NOTE A list of informative references is given in the Bibliography. 3 Abbreviated

49、terms For the purposes of this document, the following abbreviated terms apply. APR automatic power reduction DCF dispersion compensating fibre DOP degree of polarization DRA distributed Raman amplification DRB double Rayleigh backscattering DWDM dense wavelength division multiplexing EDFA erbium-doped fibre amplifier ESA electrical spectrum analyzer FBG fibre Bragg grating FWHM full width half maximum GFF gain flattening