IEC TR 61282-3:2006

Fibre optic communication system design guides - Part 3: Calculation of link polarization mode dispersion

This technical report provides guidelines for the calculation of polarisation mode dispersion (PMD) in fibre optic systems. It accomodates the statistical variation of PMD and differential group delay (DGD) of optical fibre cables and optical components in an optical link. Example calculations are given, including concatenating individual optical fibre cables. The calculations describe first order PMD only.

General Information

• Status: Published
• Publication Date: 24-Oct-2006
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 33.180.01 - Fibre optic systems in general
• Technical Committee: SC 86C - Fibre optic systems and active devices
• Drafting Committee: WG 1 - TC 86/SC 86C/WG 1
• Current Stage: PPUB - Publication issued
• Start Date: 31-Oct-2006
• Completion Date: 25-Oct-2006

Relations

• Revises: IEC TR 61282-3:2002 - Fibre optic communication system design guides - Part 3: Calculation of polarization mode dispersion
• Effective Date: 05-Sep-2023

Standards Content (Sample)

TECHNICAL IEC
REPORT TR 61282-3
Second edition
2006-10
Fibre optic communication system design guides –
Part 3:
Calculation of link polarization mode dispersion
Reference number
IEC/TR 61282-3:2006(E)
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TECHNICAL IEC
REPORT TR 61282-3
Second edition
2006-10
Fibre optic communication system design guides –
Part 3:
Calculation of link polarization mode dispersion

© IEC 2006 ⎯ Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.iec.ch
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Commission Electrotechnique Internationale V

International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – TR 61282-3 © IEC:2006(E)
CONTENTS
FOREWORD.3
INTRODUCTION.5

1 Scope.6
2 Basic design models for total system PMD performance.6
2.1 Notation.6
2.2 Calculation of system PMD .7
3 Calculation of cabled fibre PMD .9
3.1 General .9
3.2 Method 1: Calculating PMD , the PMD link design value.11
Q
3.3 Method 2: Calculating the probability of exceeding DGD .14
max
3.4 Equivalence of methods.18
4 Calculation of optical component PMD .20
5 Summary of acronyms and symbols .20

Annex A (informative) PMD concatenation fundamentals .22
Annex B (informative) Combining Maxwell extrema from two populations.26
Annex C (informative) Worked example.30
Annex D (informative) Relationship of probability to system performance .31
Annex E (informative) Concatenation experiment.32

Bibliography .34

Figure 1 – Various passing distributions .15
Figure 2 – Worst case approach assumption .17
Figure 3 – Convolution of two Diracs .17
Figure 4 – Equivalence envelopes for method 1/2 defaults.19
Figure A.1 – Sum of randomly rotated elements.25
Figure A.2 – Sum of randomly rotated elements.25

Table 1 – Probability based on wavelength average.9
Table 2 – Acronyms and definitions .21
Table 3 – Symbols and clause of definition .21
Table E.1 – Concatenation math verification .33

TR 61282-3 © IEC:2006(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC COMMUNICATION SYSTEM DESIGN GUIDES –

Part 3: Calculation of link polarization mode dispersion

FOREWORD
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose 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 61282-3, which is a technical report, has been prepared by subcommittee 86C: Fibre optic
systems and active devices, of IEC technical committee 86: Fibre optics.
This second edition cancels and replaces the first edition published in 2002. It is a technical
revision that includes the following significant changes:
a) the title has been changed to better reflect its applicability to links;
b) Equations (1) and (2) were simplified in order to align with agreements in the ITU-T.

– 4 – TR 61282-3 © IEC:2006(E)
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
86C/701/DTR 86C/720/RVC
Full information on the voting for the approval of this technical report can be found in the report
on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61282 series, published under the general title Fibre optic communication
system design guides, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until the
maintenance result 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, or
• amended.
A bilingual version of this publication may be issued at a later date.

TR 61282-3 © IEC:2006(E) – 5 –
INTRODUCTION
Polarization mode dispersion (PMD) is usually described in terms of a differential group delay
(DGD), which is the time difference between the principal states of polarization of an optical
signal at a particular wavelength and time. PMD in cabled fibres and optical components
causes an optical pulse to spread in the time domain, which may impair the performance of
a fibre optic telecommunication system, as defined in IEC 61281-1.

– 6 – TR 61282-3 © IEC:2006(E)
FIBRE OPTIC COMMUNICATION SYSTEM DESIGN GUIDES –

Part 3: Calculation of link polarization mode dispersion

1 Scope
This part of IEC 61282 provides guidelines for the calculation of polarization mode dispersion
(PMD) in fibre optic systems to accommodate the statistical variation of PMD and differential
group delay (DGD) in optical fibre cables and components.
This technical report describes methods for calculating PMD due to optical fibre cables and
optical components in an optical link. The calculations are compatible with those documented
in the outdoor optical fibre cable specification IEC 60794-3. Example calculations are given to
illustrate the methods for calculating total optical link PMD from typical cable and optical
component data. The calculations include the statistics of concatenating individual optical fibre
cables drawn from a specified distribution. The calculations assume that all components have
PMD equal to the maximum specified value.
The calculations described cover first order PMD only. The following subject areas are
currently beyond the scope of this technical report, but remain under study:
– calculation of second and higher order PMD;
– accommodation of components with polarization dependent loss (PDL) – if it is assumed
that PDL is negligible in optical fibre cables;
– system impairments (power penalty) due to PMD;
– interaction with chromatic dispersion and other nonlinear effects.
Measurement of PMD is beyond the scope of this technical report. Methods of measurement of
PMD of optical fibre and cable are given in IEC 60793-1-48. The measurement of optical
amplifier PMD is in IEC 61290-11-1. The measurement of component PMD is in
IEC 61300-3-32. Measurement of link PMD is given in 61280-4-4. A general theory and
guidance on measurements is given in 61282-9.
2 Basic design models for total system PMD performance
2.1 Notation
For cabled fibre and components with randomly varying DGD, the PMD frequency domain
measurement is based on averaging the individual DGD values for a range of wavelengths. The
probability density function of DGD values is known to be Maxwell for fibre, and is assumed to
be Maxwell, in effect, for components. The single parameter for the Maxwell distribution scales
with the PMD value.
For long fibre and cable (typically longer than 500 m to 1 000 m), the PMD value is divided by
the square root of the length to obtain the PMD coefficient. For components, the PMD value is
reported without normalization. T
...