1、 IEC/TR 61282-11 Edition 1.0 2012-05 TECHNICAL REPORT Fibre optic communication system design guides Part 11:Multimode launch conditions IEC/TR 61282-11:2012(E)Copyrighted material licensed to BR Demo by Thomson Reuters(Scientific),Inc.,downloaded on Nov-28-2014 by James Madison.No further reproduct
2、ion or distribution is permitted.Uncontrolled when printed.THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2012 IEC,Geneva,Switzerland All rights reserved.Unless otherwise specified,no part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical,inclu
3、ding 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 obtaining additional rights to this publication,please contact the address below or y
4、our local IEC member National Committee for further information.IEC Central Office Tel.:+41 22 919 02 11 3,rue de Varemb Fax:+41 22 919 03 00 CH-1211 Geneva 20 infoiec.ch Switzerland www.iec.ch About the IEC The International Electrotechnical Commission(IEC)is the leading global organization that pr
5、epares and publishes International Standards for all electrical,electronic and related technologies.About IEC publications The technical content of IEC publications is kept under constant review by the IEC.Please make sure that you have the latest edition,a corrigenda or an amendment might have been
6、 published.Useful links:IEC publications search-www.iec.ch/searchpub The advanced search enables you to find IEC publications by a variety of criteria(reference number,text,technical committee,).It also gives information on projects,replaced and withdrawn publications.IEC Just Published-webstore.iec
7、.ch/justpublished Stay up to date on all new IEC publications.Just Published details all new publications released.Available on-line and also once a month by email.Electropedia-www.electropedia.org The worlds leading online dictionary of electronic and electrical terms containing more than 30 000 te
8、rms and definitions in English and French,with equivalent terms in additional languages.Also known as the International Electrotechnical Vocabulary(IEV)on-line.Customer Service Centre-webstore.iec.ch/csc If you wish to give us your feedback on this publication or need further assistance,please conta
9、ct the Customer Service Centre:csciec.ch.Copyrighted material licensed to BR Demo by Thomson Reuters(Scientific),Inc.,downloaded on Nov-28-2014 by James Madison.No further reproduction or distribution is permitted.Uncontrolled when printed.IEC/TR 61282-11 Edition 1.0 2012-05 TECHNICAL REPORT Fibre o
10、ptic communication system design guides Part 11:Multimode launch conditions INTERNATIONAL ELECTROTECHNICAL COMMISSION V ICS 33.180.01 PRICE CODE ISBN 978-2-88912-078-9 Registered trademark of the International Electrotechnical Commission Warning!Make sure that you obtained this publication from an a
11、uthorized distributor.Copyrighted material licensed to BR Demo by Thomson Reuters(Scientific),Inc.,downloaded on Nov-28-2014 by James Madison.No further reproduction or distribution is permitted.Uncontrolled when printed.2 TR 61282-11 IEC:2012(E)CONTENTS FOREWORD.4 INTRODUCTION.6 1 Scope.7 2 Normati
12、ve references.7 3 Terms and definitions.7 4 Background.8 5 Metrics for multimode launch conditions.8 General.8 5.1 Coupled power ratio(CPR).9 5.2 Mode power distribution/relative power distribution(MPD/RPD).9 5.3 Encircled flux(EF).10 5.46 Uncertainties.10 General.10 6.1 Measurement model and uncert
13、ainties.10 6.2 Uncertainty due to the setup.11 6.3 Uncertainty due to the power meter.11 6.4 Random uncertainties.11 6.5 Uncertainty due to fibre manipulation.11 6.5.1 Uncertainties due to launch conditions.12 6.5.2 Example of uncertainty accumulation.13 6.67 Encircled flux envelope theory and assum
14、ptions.14 Mode field eigenfunctions.14 7.1 Connections,attenuation and the encircled flux template.16 7.2 Target weights.17 7.3 Coupling matrix calculations.20 7.48 Wavelength bias correction to EF targets/limits with spectrally broad sources.21 General.21 8.1 Modified spectrum assumptions.21 8.2 De
15、termining the EF targets.22 8.3 Determining the EF limits.23 8.4 Validating the EF limits.24 8.5Annex A(informative)IEC international standards related to multimode launch conditions.26 Annex B(informative)Coupled power ratio measurement for fibre-optic sources.28 Annex C(informative)Limits on RPD a
16、nd MPD.30 Bibliography.35 Figure 1 Uncertainties due to the launch conditions for a given loss.13 Figure 2 Comparison of target weights.18 Figure 3 Incremental loss using OFL launch.19 Figure 4 Incremental loss using target launch.20 Figure C.1 Example of a characteristic MTF.31 Figure C.2 Relative power distribution(RPD)specification.33 Figure C.3 Example of a characteristic MPD.33 Copyrighted material licensed to BR Demo by Thomson Reuters(Scientific),Inc.,downloaded on Nov-28-2014 by Jame
