SIST EN 61290-4-2:2011

Optical amplifiers - Test methods - Part 4-2: Gain transient parameters - Broadband source method (IEC 61290-4-2:2011)

This part of IEC 61290-4 applies to optical amplifiers (OAs) and optically amplified elementary sub-systems. More specifically, it applies to OAs using active fibres (optical fibre amplifiers, OFAs) containing rare-earth dopants, such as erbium doped fibre amplifiers (EDFAs), presently commercially available, as indicated in IEC 61291-1. The object of this part of IEC 61290-4 is to establish uniform requirements for accurate and reliable measurements, by means of the broadband source method, of the transient response of OFAs to dynamic changes in their input power, as defined in IEC 61290-4-1:2011. The broadband source method is different from the two-wavelength method described in IEC 61290-4-1:- in that the saturating signal is not located at a single wavelength, but is rather spread out across the entire specified DWDM transmission band of the OFA-under-test (e.g. the C-Band, 1 525 nm to 1 565 nm). Thus, this method may be relevant to the characterization of transient events where the DWDM signals that are added or dropped are more or less uniformly spread across the transmission band. The difference between the two measurement methods is discussed in more detail in Annex A.

Lichtwellenleiter-Verstärker - Prüfverfahren - Teil 4-2: Transiente Verstärkerparameter - Breitbandquellen Verfahren (IEC 61290-4-2:2011)

Amplificateurs optiques - Méthodes d’essai - Partie 4-2: Paramètres de gain transitoire - Méthode par source large bande (CEI 61290-4-2:2011)

La CEI 61290-4-2:2011 s'applique aux amplificateurs optiques (AO) et aux sous-systèmes élémentaires à amplification optique. Plus précisément, Elle s'applique aux AO utilisant des fibres actives (amplificateurs à fibres optiques, AFO), contenant des dopants aux terres rares, tels que les amplificateurs à fibre dopée à l'erbium (EDFA), actuellement disponibles sur le marché, comme l'indique la CEI 61291-1. L'objet de la présente partie de la CEI 61290-4 est d'établir des exigences uniformes en vue de mesures précises et fiables, au moyen de la méthode par source large bande, de la réponse transitoire des AFO aux variations dynamiques de leur puissance d'entrée, comme défini dans la CEI 61290-4-1:2011.   Cette publication doit être lue conjointement avec la CEI 61291-1:2006.

Optični ojačevalniki - Preskusne metode - 4-2. del: Prehodni parametri ojačenja - Metoda s širokopasovnim virom (IEC 61290-4-2:2011)

Ta del IEC 61290-4 velja za optične ojačevalnike (OA) in optično ojačene elementarne podsisteme. Bolj specifično velja za OA, ki uporabljajo aktivna vlakna (ojačevalniki z optičnimi vlakni, OFA), ki vsebujejo ojačitve z redkimi zemeljskimi elementi, kot so z erbijem ojačeni optični ojačevalniki (EDFA), trenutno komercialno dostopni, kot navaja IEC 61291-1. Namen tega dela IEC 61290-4 je vzpostaviti enotne zahteve za točno in zanesljivo merjenje prehodnega odziva OFA na dinamične spremembe vhodne moči z metodo s širokopasovnim virom, kot je opredeljeno v IEC 61290-4-1:2011. Metoda s širokopasovnim virom je drugačna od dvovalovne metode, opisane v IEC 61290-4-1:- saturacijski signal ni lociran na eni sami valovni dolžini, pač pa je razpršen po celotnem določenem prenosnem pasu DWDM preskušanega OFA (npr. C-pas, 1525 nm do 1565 nm). Zato je ta metoda lahko primerna za karakterizacijo prehodnih dogodkov, pri katerih so signali DWDM, ki se dodajajo ali odvzemajo, bolj ali manj enakomerno razpršeni po prenosnem pasu. Razliko med obema merilnima metodama podrobneje obravnava dodatek A.

General Information

• Status: Published
• Publication Date: 12-Oct-2011
• ICS: 33.180.30 - Optic amplifiers
• Technical Committee: iTEL - Communication cables
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 29-Sep-2011
• Due Date: 04-Dec-2011
• Completion Date: 13-Oct-2011
• Ref Project: EN 61290-4-2:2011 - Optical amplifiers - Test methods - Part 4-2: Gain transient parameters - Broadband source method

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 61290-4-2:2011
01-november-2011
2SWLþQLRMDþHYDOQLNL3UHVNXVQHPHWRGHGHO3UHKRGQLSDUDPHWULRMDþHQMD
0HWRGDVãLURNRSDVRYQLPYLURP,(&
Optical amplifiers - Test methods - Part 4-2: Gain transient parameters - Broadband
source method (IEC 61290-4-2:2011)
Lichtwellenleiter-Verstärker - Prüfverfahren - Teil 4-2: Transiente Verstärkerparameter -
Breitbandquellen Verfahren (IEC 61290-4-2:2011)
Amplificateurs optiques - Méthodes d’essai - Partie 4-2: Paramètres de gain transitoire -
Méthode par source large bande (CEI 61290-4-2:2011)
Ta slovenski standard je istoveten z: EN 61290-4-2:2011
ICS:
33.180.30 2SWLþQLRMDþHYDOQLNL Optic amplifiers
SIST EN 61290-4-2:2011 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST EN 61290-4-2:2011

---------------------- Page: 2 ----------------------

SIST EN 61290-4-2:2011

EUROPEAN STANDARD
EN 61290-4-2

NORME EUROPÉENNE
September 2011
EUROPÄISCHE NORM

ICS 33.180.30


English version


Optical amplifiers -
Test methods -
Part 4-2: Gain transient parameters -
Broadband source method
(IEC 61290-4-2:2011)


Amplificateurs optiques -  Lichtwellenleiter-Verstärker -
Méthodes d’essai - Prüfverfahren -
Partie 4-2: Paramètres de gain Teil 4-2: Transiente Verstärkerparameter -
transitoire - Breitbandquellen Verfahren
Méthode par source large bande (IEC 61290-4-2:2011)
(CEI 61290-4-2:2011)





This European Standard was approved by CENELEC on 2011-08-17. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels


© 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61290-4-2:2011 E

---------------------- Page: 3 ----------------------

SIST EN 61290-4-2:2011
EN 61290-4-2:2011 - 2 -
Foreword
The text of document 86C/957/CDV, future edition 1 of IEC 61290-4-2, prepared by SC 86C, "Fibre optic
systems and active devices", of IEC TC 86, "Fibre optics", was submitted to the IEC-CENELEC parallel
vote and approved by CENELEC as EN 61290-4-2:2011.

The following dates are fixed:
(dop) 2012-05-17
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2014-08-17
• latest date by which the national
standards conflicting with the
document have to be withdrawn

This standard is to be used in conjunction with EN 61291-1.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent
rights.

Endorsement notice
The text of the International Standard IEC 61290-4-2:2011 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 61290-1-1 NOTE  Harmonized as EN 61290-1-1.
IEC 61290-1-2 NOTE  Harmonized as EN 61290-1-2.
IEC 61290-1-3 NOTE  Harmonized as EN 61290-1-3.

---------------------- Page: 4 ----------------------

SIST EN 61290-4-2:2011
- 3 - EN 61290-4-2:2011
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

IEC 61290-4-1 2011 Optical amplifiers - Test methods - EN 61290-4-1 2011
Part 4-1: Gain transient parameters - two-
wavelength method


IEC 61291-1 - Optical amplifiers - EN 61291-1 -
Part 1: Generic specification

---------------------- Page: 5 ----------------------

SIST EN 61290-4-2:2011

---------------------- Page: 6 ----------------------

SIST EN 61290-4-2:2011

IEC 61290-4-2
®

Edition 1.0 2011-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside


Optical amplifiers – Test methods –
Part 4-2: Gain transient parameters – Broadband source method

Amplificateurs optiques – Méthodes d’essai –
Partie 4-2: Paramètres de gain transitoire – Méthode par source large bande

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX R
ICS 33.180.30 ISBN 978-2-88912-573-9

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 7 ----------------------

SIST EN 61290-4-2:2011
– 2 – 61290-4-2 © IEC:2011
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope and object . 6
2 Normative references. 6
3 Terms, definitions and abbreviations . 6
3.1 General . 6
3.2 Terms and definitions . 9
3.3 Abbreviated terms . 10
4 Apparatus . 10
5 Test sample . 12
6 Procedure . 12
7 Calculations . 13
8 Test results . 14
Annex A (informative) Comparison between two-wavelength method and broadband
method . 15
Bibliography . 17

Figure 1 – Definitions of rise and fall times for (a) a channel addition event, and (b) a
channel removal event . 7
Figure 2 – OFA transient gain response for (a) a channel removal event, and (b) a

channel addition event . 8
Figure 3 – Transient measurement test set-up for broadband source method . 11
Figure A.1 – Effect of non-flat gain spectrum on gain offset . 15
Figure A.2 – Different transient suppression response for different types of saturating
signals . 16

Table 1 – Examples of “add” and “drop” scenarios for transient control measurement . 13
Table 2 – Typical results of transient control measurement for a C-Band EDFA . 14

---------------------- Page: 8 ----------------------

SIST EN 61290-4-2:2011
61290-4-2 © IEC:2011 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

OPTICAL AMPLIFIERS –
TEST METHODS –

Part 4-2: Gain transient parameters –
Broadband source method


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 standardization 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 entrusted 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 International 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 since 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 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 in 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
assessment 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, employees, 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 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 the 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.
International Standard IEC 61290-4-2 has been prepared by subcommittee 86C: Fibre optic
systems and active devices, of IEC technical committee 86: Fibre optics.
This standard shall be used in conjunction with IEC 61291-1. It was established on the basis of
the second (2006) edition of that standard.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.

---------------------- Page: 9 ----------------------

SIST EN 61290-4-2:2011
– 4 – 61290-4-2 © IEC:2011
The text of this standard is based on the following documents:
CDV Report on voting
86C/957/CDV 86C/991/RVC

Full information on the voting for the approval of this standard 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 61290 series, published under the general title Optical amplifiers –
Test methods can be found on the IEC website.
The committee has decided that the contents of this 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, or
• amended.

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 this document using a colour printer.

---------------------- Page: 10 ----------------------

SIST EN 61290-4-2:2011
61290-4-2 © IEC:2011 – 5 –
INTRODUCTION
This part of IEC 61290-4 is devoted to the subject of optical amplifiers. The technology of
optical amplifiers is quite new and still emerging; hence amendments and new editions to this
standard can be expected.
Each abbreviation introduced in this standard is explained in the text at least the first time it
appears. However, for an easier understanding of the whole text, a list of all abbreviations used
in this standard is given in 3.3.

---------------------- Page: 11 ----------------------

SIST EN 61290-4-2:2011
– 6 – 61290-4-2 © IEC:2011
OPTICAL AMPLIFIERS –
TEST METHODS –

Part 4-2: Gain transient parameters –
Broadband source method



1 Scope and object
This part of IEC 61290-4 applies to optical amplifiers (OAs) and optically amplified elementary
sub-systems. More specifically, it applies to OAs using active fibres (optical fibre amplifiers,
OFAs) containing rare-earth dopants, such as erbium doped fibre amplifiers (EDFAs), presently
commercially available, as indicated in IEC 61291-1.
The object of this part of IEC 61290-4 is to establish uniform requirements for accurate and
reliable measurements, by means of the broadband source method, of the transient response of
OFAs to dynamic changes in their input power, as defined in IEC 61290-4-1:2011.
The broadband source method is different from the two-wavelength method described in
IEC 61290-4-1:– in that the saturating signal is not located at a single wavelength, but is rather
spread out across the entire specified DWDM transmission band of the OFA-under-test (e.g. the
C-Band, 1 525 nm to 1 565 nm). Thus, this method may be relevant to the characterization of
transient events where the DWDM signals that are added or dropped are more or less uniformly
spread across the transmission band. The difference between the two measurement methods is
discussed in more detail in Annex A.
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 latest edition of
the referenced document (including any amendments) applies.
IEC 61290-4-1:2011, Optical amplifiers – Test methods – Part 4-1: Gain transient parameters –
Two wavelength method
IEC 61291-1, Optical fibre amplifiers – Part 1: Generic specification
3 Terms, definitions and abbreviations
3.1 General
When the input power to an OFA operating in saturation changes sharply, the gain of the
amplifier will typically exhibit a transient response before settling back into the required gain.
This response is dictated both by the optical characteristics of the active fibre within the OFA,
as well as the performance of the automatic gain control (AGC) mechanism.
Since a change in input power typically occurs when part of the DWDM channels within the
specified transmission band are dropped or added, definitions are provided that describe a
dynamic event leading to a transient response. Rise and fall time definitions are shown in
Figure 1.

---------------------- Page: 12 ----------------------

SIST EN 61290-4-2:2011
61290-4-2 © IEC:2011 – 7 –
100 %
of change
90 %
of change
10 %
of change
Rise
time
Time
Channel
Channel
addition start
addition end
(a) IEC  1582/11

10 %
of change
90 %
of change
100 %
of change
Fall
time
Time
Channel
Channel
removal start
removal end
(b)
IEC  1583/11

Figure 1 – Definitions of rise and fall times for (a) a channel addition event,
and (b) a channel removal event
The parameters generally used to characterize the transient gain behaviour of a gain controlled
OFA for the case of channel addition/removal are defined in Figure 2. Figure 2(a) specifically
represents the time dependence of the gain of one of the surviving channels when channels
are removed. Likewise the transient gain behaviour of a pre-existing channel for the case when
channels are added is shown in Figure 2(b). The main transient parameters are: transient gain

Input power to EDFA
Input power to EDFA
(linear a.u.)
(linear a.u.)

---------------------- Page: 13 ----------------------

Transient gain response time
constant (settling time)
SIST EN 61290-4-2:2011
– 8 – 61290-4-2 © IEC:2011
response time constant (setting time), gain offset, transient net gain overshoot, and transient
net gain undershoot. The transient gain overshoot and undershoot are particularly critical to
carriers and network equipment manufacturers (NEMs) given that the speed and amplitude of
gain fluctuations compound through the network as the optical signal passes through an
increasing number of cascaded amplifiers. Properly designed optical amplifiers have very small
values for these transient parameters.
Net gain
overshoot
Gain
Gain
overshoot
stability
Final
gain
Gain offset
Initial
Gain
Net gain
gain
undershoot
undershoot
Time
(a)
IEC  1584/11

Net gain
Gain
Overshoot
overshoot
Initial
Gain offset
gain
Final
gain
Gain
stability
Gain
Net gain
undershoot
undershoot
Transient gain response time
constant (settling time)
Time
(b)
IEC  1585/11

Figure 2 – OFA transient gain response for (a) a channel removal event,
and (b) a channel addition event



Gain (dB)
Gain (dB)

---------------------- Page: 14 ----------------------

SIST EN 61290-4-2:2011
61290-4-2 © IEC:2011 – 9 –
3.2 Terms and definitions
For the purposes of this document, the following terms, definitions and abbreviations apply.
3.2.1
surviving (pre-existing) signal
op
...