Table Of Content

Fibre Optic Cabling Fiber Optic Cabling Second Edition Barry Elliott Mike Gilmore OXFORD AUCKLAND BOSTON JOHANNESBURG MELBOURNE NEW DELHI Newnes An imprint of Butterworth-Heinemann Linacre House, Jordan Hill, Oxford OX2 8DP 225 Wildwood Avenue, Woburn, MA 01801-2041 A division of Reed Educational and Professional Publishing Ltd A member of the Reed Elsevier plc group First published 1991 Second edition 2002 © Mike Gilmore and Barry Elliott 2002 All rights reserved. No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright holder except in accordance with the provisions of the Copyright, Designs and Patents Act 1988 or under the terms of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London, England W1P 0LP. Applications for the copyright holder’s written permission to reproduce any part of this publication should be addressed to the publishers British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library ISBN 0 7506 5013 3 Composition by Scribe Design, Gillingham, Kent, UK Printed and bound in Great Britain .........................................................P.reface ...................................A..b..b...r.e..v..iations .............................S...a..f.e..t.y.. .s.t.a. tement Cabling as .a..n.. .o..p..e..r.a..t.i.n..g.. system 1 Fiber optic communications and the data cabling revolution................................ 1 Communications cabling and its role.............. 2 Fiber optics and the cabling market ............... 3 Fiber optic cabling as an operating system.... 7 The economics of fiber optic cabling.............. 9 2 Optical fiber theory................................... 2 Basic fiber parameters ................................... 2 Refractive index.............................................. 12 Laws of reflection and refraction .................... 15 Optical fiber and total inter nal reflection........ 18 Optical fiber constr uction and definitions....... 20 The ideal fiber................................................. 21 Light acceptance and numerical aper ture ..... 22 Light loss and attenuation .............................. 24 Intrinsic loss mechanisms .............................. 24 Modal distribution and fiber attenuation ......... 27 Extrinsic loss mechanisms ............................. 28 Impact of numerical aper ture on attenuation...................................................... 31 Operational wavelength windows................... 31 Bandwidth....................................................... 31 Step index and graded index fibers................ 34 Modal conversion and its effect upon bandwidth....................................................... 36 Single mode transmission in optical fiber....... 39 Bandwidth specifications for optical fiber ....... 45 System design, bandwidth utilization and fiber geometries.............................................. 46 Optical fiber geometries ................................. 47 The new family of single mode fiber............... 48 Plastic optical fiber ......................................... 52 3 Optical fiber production t.e..c..h..niques .M...a..n..u..f.a..c..t.u..r.i.n..g.. .t.e..c..hniques Preform manufacture...................................... 55 Stepped index fiber preforms......................... 55 All-silica fiber preforms................................... 56 Fiber manufacture from preforms................... 63 Fiber compatibility .......................................... 66 Clad silica fibers............................................. 66 Plastic optical fiber ......................................... 67 Radiation hardness ........................................ 68 Primary coating processes............................. 70 4 Optical fiber (cid:150) connection theory and ........................b..a..s..i.c.. .t..e..c..h..niques ...........C..o..n..n..e..c..t.i.o..n.. .t.e..c..hniques Connection categories.................................... 73 Insertion loss .................................................. 73 Basic parametric mismatch............................ 74 Fusion splice joints......................................... 78 Mechanical alignment..................................... 79 Joint loss, fiber geometry and preparation ..... 84 Return loss ..................................................... 84 5 Practical aspects of connection ............................................t.e..c..h...nology Alignment techn.i.q..u..e..s.. .w..i.t.h..in joints The joint and its specification......................... 90 Inser tion loss and component specifications.................................................. 91 The introduction of optical fiber within joint mechanisms................................................... 95 Joint mechanisms: relative cladding diameter alignment......................................... 98 Joint mechanisms: absolute cladding diameter alignment......................................... 100 6 Connectors and joints, alternatives ..........................a..n..d... .a..p..p..l.i.c.ations Splice joints.................................................... 105 Demountable connectors ............................... 110 Standards and optical connectors.................. 121 Termination: the attachment of a fiber optic connector to a cable....................................... 124 Termination as an installation technique........ 127 ...............7.. .F..i.b..e..r.. .o..p..t.i.c.. .cables ...........B..a..s..i.c. .c..a..b..l.i.n..g.. .e..lements Cabling requirements and designs................. 134 Fiber optic cable design definitions................ 135 Inter-building (external) cables....................... 138 Intra-building (internal) cables........................ 141 Fiber optic cables and optomechanical stresses.......................................................... 143 User-friendly cable designs............................ 147 The economics of optical fiber cable design............................................................. 147 8.. .O...p..t.i.c..a..l. .f..i.b..e..r. .h..i.g..hways Optical fiber installa.t.io..n..s..:. .d..e..finitions The optical fiber highway................................ 154 Optical fiber highway design .......................... 156 ..................................................... ........................................... 9 Optical fibe.r. .h...i.g..h..w...a..y.. .design Nodal design .................................................. 168 Ser vice needs................................................ 172 Optical budget................................................ 176 Bandwidth requirements................................. 185 Fiber geometry choices within the highway design............................................................. 189 ........1..0.. .C...o..m...p..o..n...e..n..t. .choice Fiber optic cable and cabl.e.. .a..s.s..emblies Connectors..................................................... 199 Splice components......................................... 200 Termination enclosures.................................. 201 11 Sp..e..c..i.f..i.c..a..t.i.o..n.. .d..e..f.inition .......T.. .e..c..h..n..i.c..a..l. .g..r.o..u..n.d r ules Operational requirement................................. 206 Design proposal ............................................. 211 Optical specification ....................................... 214 Contractual aspects of the specification agreement...................................................... 215 12 Accep.t.a..n..c..e.. .t.e..s..t.. .m...ethods ...........................................F...ix..e..d. cables Air-blown fiber testing..................................... 229 Cable assembly acceptance testing............... 229 Direct termination during installation and its effect upon quality assurance......................... 239 Termination enclosures.................................. 239 Pre-installed cabling....................................... 240 Short-range systems and test philosophies ... 240 .....1..3.. .I.n..s..t.a..l.l.a..t.i.o...n.. .p..ractice Transmission equipment and the overall contract requirement ...................................... 243 The role of the installer................................... 244 The typical installation.................................... 244 Contract management.................................... 245 Installation programme................................... 248 Termination practices..................................... 253 14 Fina.l. .a..c..c..e..p..t..a..n..c..e.. .testing .......................G...e..n..e..r.a..l. .i.n..s.pection Optical performance testing ........................... 259 Overall span attenuation measurement ......... 262 Optical time domain reflectometer testing of installed spans............................................ 267 ....................1..5.. .D...o..c..u..m....e..ntation .......C...o..n..t.r.a..c..t. .d..o..c..u..m...entation Technical documentation ............................... 275 The function of final highway documentation................................................ 283 Internationalstandards concerning project documentation................................................ 283 16 Rep.a..i.r. .a..n..d... .m...a..i.n..t.e.nance ............................................................. Repair Maintenance................................................... 289 ..................................1..7.. .C...a..s..e. study .............................P..r.e..l.i.m...i.n..a..ry ideas .............N...e..t.w...o..r.k.. .r.e..q..u..i.rements Initial implementation for inter-building cabling............................................................ 292 Materials choice ............................................. 300 Bill of materials (fiber optic content)............... 304 Installation planning........................................ 309 1..8.. .F..u...t.u..r.e.. .d...e..v..e..l.o..p.ments ...........................................E...x.o..t.i.c lasers New optical fibres........................................... 311 Next generation components ......................... 312 New coding techniques.................................. 313 Appendix A Attenuation within optical .....f.i.b..e..r..:. .i.t.s.. .m...e..a..s..u..r.ement ............................................................. Index