IEC 61291-1:2018

Optical amplifiers - Part 1: Generic specification

IEC 61291-1:2018 applies to all commercially available optical amplifiers (OAs) and optically amplified assemblies. It applies to OAs using optically pumped fibres (OFAs based either on rare-earth doped fibres or on the Raman effect), semiconductors (SOAs), and waveguides (POWAs). The object of this document is
- to establish uniform requirements for transmission, operation, reliability and environmental properties of OAs, and
- to provide assistance to the purchaser in the selection of consistently high-quality OA products for his particular applications.
Parameters specified for OAs are those characterizing the transmission, operation, reliability and environmental properties of the OA seen as a "black box" from a general point of view. In the sectional and detail specifications a subset of these parameters will be specified according to the type and application of the particular OA device or assembly. This fourth edition cancels and replaces the third edition published in 2012. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- terms have been added for parameters from IEC 61290-4-3 and IEC 61290-10-5;
- Clause 4 Classification has been removed, since this system is judged to be unused;
- the definition of polarization mode dispersion (PMD) has been simplified.
Keywords: optical amplifiers (OAs)

Amplificateurs optiques - Partie 1: Spécification générique

IEC 61291-1:2018 s’applique à tous les amplificateurs optiques (OA) et systèmes à amplification optique, disponibles sur le marché. Elle s’applique aux OA utilisant des fibres pompées optiquement (OFA basés sur des fibres dopées aux terres rares ou sur l’effet Raman), des semiconducteurs (SOA) et des guides d’ondes (POWA). Le présent document a pour objet
- d’établir des exigences uniformes pour la transmission, le fonctionnement, la fiabilité et les propriétés liées à l'environnement des OA, et
- d’aider les acheteurs à sélectionner des produits OA de qualité élevée et constante pour leurs applications.
Les paramètres spécifiés pour un OA sont ceux qui caractérisent les propriétés de transmission, de fonctionnement, de fiabilité et d’environnement de l’OA, considéré globalement comme une "boîte noire". Dans les spécifications intermédiaires et particulières, un sous-ensemble de ces paramètres sera spécifié d’après le type et l’application d’un module OA ou d’un système d’OA particulier. Cette quatrième édition annule et remplace la troisième édition parue en 2012. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- des termes ont été ajoutés pour des paramètres de l'IEC 61290-4-3 et de l'IEC 61290-10-5;
- la classification de l'Article 4 a été retirée car elle n'est pas utilisée;
- la définition de la dispersion du mode de polarisation a été simplifiée.
Mots clés: amplificateurs optiques (OA)

General Information

• Status: Published
• Publication Date: 19-Feb-2018
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 33.180.30 - Optic amplifiers
• Technical Committee: SC 86C - Fibre optic systems and active devices
• Current Stage: PPUB - Publication issued
• Start Date: 20-Feb-2018
• Completion Date: 20-Feb-2018

Standards Content (sample)

IEC 61291-1
Edition 4.0 2018-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical amplifiers –
Part 1: Generic specification
Amplificateurs optiques –
Partie 1: Spécification générique
IEC 61291-1:2018-02(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 61291-1
Edition 4.0 2018-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical amplifiers –
Part 1: Generic specification
Amplificateurs optiques –
Partie 1: Spécification générique
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.30 ISBN 978-2-8322-5404-2

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 61291-1:2018 © IEC 2018
CONTENTS

FOREWORD ........................................................................................................................... 3

1 Scope .............................................................................................................................. 5

2 Normative references ...................................................................................................... 5

3 Terms, definitions and abbreviated terms ........................................................................ 6

3.1 Overview................................................................................................................. 6

3.2 Terms and definitions .............................................................................................. 8

3.2.1 OA devices and distributed amplifiers .............................................................. 9

3.2.2 OA assemblies .............................................................................................. 23

3.3 Abbreviated terms ................................................................................................. 26

4 Requirements ................................................................................................................ 26

4.1 Preferred values ................................................................................................... 27

4.2 Sampling............................................................................................................... 27

4.3 Product identification for storage and shipping ...................................................... 27

4.3.1 Marking ......................................................................................................... 27

4.3.2 Labelling ........................................................................................................ 27

4.3.3 Packaging...................................................................................................... 27

5 Quality assessment ....................................................................................................... 27

6 Electromagnetic compatibility (EMC) requirements ........................................................ 27

7 Test methods ................................................................................................................. 27

Bibliography .......................................................................................................................... 29

Figure 1 – OA device and assemblies ..................................................................................... 7

Figure 2 – Optical amplifier in a multichannel application ........................................................ 8

Table 1 – Grouping of parameters and corresponding test methods or references ................ 28

---------------------- Page: 4 ----------------------
IEC 61291-1:2018 © IEC 2018 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL AMPLIFIERS –
Part 1: Generic specification
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

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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 61291-1 has been prepared by subcommittee 86C: Fibre optic

systems and active devices, of IEC technical committee 86: Fibre optics.

This fourth edition cancels and replaces the third edition published in 2012. This edition

constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:
a) terms have been added for parameters from IEC 61290-4-3 and IEC 61290-10-5;

b) Clause 4 Classification has been removed, since this system is judged to be unused;

c) the definition of polarization mode dispersion (PMD) has been simplified.
---------------------- Page: 5 ----------------------
– 4 – IEC 61291-1:2018 © IEC 2018
The text of this International Standard is based on the following documents:
CDV Report on voting
86C/1460/CDV 86C/1498/RVC

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 61291 series, published under the general title Optical amplifiers,

can be found on the IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
---------------------- Page: 6 ----------------------
IEC 61291-1:2018 © IEC 2018 – 5 –
OPTICAL AMPLIFIERS –
Part 1: Generic specification
1 Scope

This part of IEC 61291 applies to all commercially available optical amplifiers (OAs) and

optically amplified assemblies. It applies to OAs using optically pumped fibres (OFAs based

either on rare-earth doped fibres or on the Raman effect), semiconductors (SOAs), and

waveguides (POWAs).
The object of this document is

– to establish uniform requirements for transmission, operation, reliability and environmental

properties of OAs, and

– to provide assistance to the purchaser in the selection of consistently high-quality OA

products for his particular applications.

Parameters specified for OAs are those characterizing the transmission, operation, reliability

and environmental properties of the OA seen as a "black box" from a general point of view. In

the sectional and detail specifications a subset of these parameters will be specified

according to the type and application of the particular OA device or assembly.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their

content constitutes requirements 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 60050-731, International Electrotechnical Vocabulary – Chapter 731: Optical fibre

communication (available at http://www.electropedia.org)
IEC 61290 (all parts), Optical amplifiers – Test methods

IEC 61290-1-1, Optical amplifiers – Test methods – Part 1-1: Power and gain parameters –

Optical spectrum analyzer method

IEC 61290-1-2, Optical amplifiers – Test methods – Part 1-2: Power and gain parameters –

Electrical spectrum analyzer method

IEC 61290-1-3, Optical amplifiers – Test methods – Part 1-3: Power and gain parameters –

Optical power meter method

IEC 61290-3-1, Optical amplifiers – Test methods – Part 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 61290-4-1, Optical amplifiers – Test methods – Part 4-1: Gain transient parameters –

Two wavelength method
---------------------- Page: 7 ----------------------
– 6 – IEC 61291-1:2018 © IEC 2018

IEC 61290-4-2, Optical amplifiers – Test methods – Part 4-2: Gain transient parameters –

Broadband source method

IEC 61290-4-3, Optical amplifiers – Test methods – Part 4-3: Power transient parameters –

Single channel optical amplifiers in output power control

IEC 61290-5-1, Optical amplifiers – Test methods – Part 5-1: Reflectance parameters –

Optical spectrum analyzer method

IEC 61290-5-2, Optical amplifiers – Test methods – Part 5-2: Reflectance parameters –

Electrical spectrum analyzer method

IEC 61290-5-3, Optical fibre amplifiers – Basic specification– Part 5-3: Test methods for

reflectance parameters – Reflectance tolerance using an electrical spectrum analyzer

IEC 61290-6-1, Optical fibre amplifiers – Basic specification – Part 6-1: Test methods for

pump leakage parameters – Optical demultiplexer

IEC 61290-7-1, Optical amplifiers – Test methods – Part 7-1: Out-of-band insertion losses –

Filtered optical power meter method

IEC 61290-10-1, Optical amplifiers – Test methods – Part 10-1: Multichannel parameters –

Pulse method using an optical switch and optical spectrum analyzer

IEC 61290-10-2, Optical amplifiers – Test methods – Part 10-2: Multichannel parameters –

Pulse method using a gated optical spectrum analyzer

IEC 61290-10-3, Optical amplifiers – Test methods – Part 10-3: Multichannel parameters –

Probe methods

IEC 61290-10-4, Optical amplifiers – Test methods – Part 10-4: Multichannel parameters –

Interpolated source subtraction method using an optical spectrum analyzer

IEC 61290-10-5, Optical amplifiers – Test methods – Part 10-5: Multichannel parameters –

Distributed Raman amplifier gain and noise figure

IEC 61290-11-1, Optical amplifiers – Test methods – Part 11-1: Polarization mode dispersion

parameter – Jones matrix eigenanalysis (JME)

IEC 61290-11-2, Optical amplifiers – Test methods – Part 11-2: Polarization mode dispersion

parameter – Poincaré sphere analysis method

IEC 61291-5-2, Optical amplifiers – Part 5-2: Qualification specifications – Reliability

qualification for optical fibre amplifiers
IEC TR 61931, Fibre optic – Terminology
3 Terms, definitions and abbreviated terms
3.1 Overview

The definitions listed in 3.2 refer to the meaning of the terms used in the specifications of

OAs. Only those parameters listed in the appropriate specification template, as in

IEC 61291-2 and IEC 61291-4, are intended to be specified.
---------------------- Page: 8 ----------------------
IEC 61291-1:2018 © IEC 2018 – 7 –

The list of parameter definitions of OAs, given in 3.2, is divided into two parts: the first part,

3.2.1, lists those parameters relevant for OA devices, namely power, pre-, line- and

distributed amplifiers; the second part, 3.2.2, lists the parameters relevant for optically

amplified, elementary assemblies, namely the optically amplified transmitter (OAT) and the

optically amplified receiver (OAR).

In any case where the value of a parameter is given for a particular device, it will be

necessary to specify certain appropriate operating conditions such as temperature, bias

current, pump optical power. In Clause 3, two different operating conditions are referred to:

nominal operating conditions, which are those suggested by the manufacturer for normal use

of the OA, and limit operating conditions, in which all the parameters adjustable by the user

(e.g. temperature, gain, pump laser injection current) are at their maximum values, according

to the absolute maximum ratings stated by the manufacturer.

The OA shall be considered as a "black box", as shown in Figure 1. The OA device shall have

two optical ports, namely an input and an output port (Figure 1 a)). The OAT and OAR shall

be considered as an OA integrated on the transmitter side or on the receiver side,

respectively. Both kinds of integration imply that the connection between the transmitter or the

receiver and the OA is proprietary and not to be specified. Consequently, only the optical

output port can be defined for the OAT [after the OA, as shown in Figure 1 b)] and only the

optical input port can be defined for the OAR [before the OA, as shown in Figure 1 c)]. The

optical ports may consist of unterminated fibres or optical connectors. Electrical connections

for power supply (not shown in Figure 1) are also necessary. Following this "black box"

approach, the typical loss of one connection and the corresponding uncertainty will be

included within the values of gain, noise figure and other parameters of the OA device.

NOTE 1 For distributed amplifiers, as described in Clause 4, this black-box configuration can be simulated for test

purposes, for example by attaching a reference fibre to test a Raman pump unit.
Input Output Output Input
Tx
OA OA Rx
port port port
port
IEC
IEC
IEC
a) – OA device b) – OAT c) – OAR
Figure 1 – OA device and assemblies

The OA amplifies signals in a nominal operating wavelength region. In addition, other signals

outside of the band of operating wavelength can in some applications, also cross the OA. The

purpose of these out-of-band signals and their wavelength, or wavelength region, can be

specified in the detail specifications.

When signals at multiple wavelengths are incident on the OA, as is the case in multichannel

systems, suitable adjustment of the definitions of some existing relevant parameters is

needed together with the introduction of definitions of new parameters relevant to this

different application.

A typical configuration of an OA in a multichannel application is shown in Figure 2. At the

transmitting side, m signals, coming from m optical transmitters, Tx , Tx , . . . Tx , each with a

1 2 m

unique wavelength, λ , λ , . . . λ , respectively, are combined by an optical multiplexer (OM).

1 2 m

At the receiving side, the m signals at λ , λ , . . . λ , are separated with an optical

1 2 m

demultiplexer (OD) and routed to separate optical receivers, Rx , Rx , . . . Rx , respectively.

1 2 m

To characterize the OA in this multichannel application, an input reference plane and an

output reference plane are defined at the OA input and output ports, respectively, as shown in

Figure 2.
---------------------- Page: 9 ----------------------
– 8 – IEC 61291-1:2018 © IEC 2018
Input Output
Tx Rx
reference
1 reference 1
plane
plane
2 2
OM OD
P OA P
i1 o1
P P
i2 o2
. . . . . .
Tx Rx
P P
m m
im om
P (λ)
ASE
IEC
Figure 2 – Optical amplifier in a multichannel application

At the input reference plane, m input signals at the m wavelengths are considered, each with a

unique power level, P , P , . . . P , respectively. At the output reference plane, m output

i1 i2 im

signals at the m wavelengths, resulting from the optical amplification of the corresponding m

input signals, are considered, each with power level P , P , . . . P , respectively. Moreover,

o1 o2 om

the amplified spontaneous emission, ASE, with a noise power spectral density, P (λ), is

ASE
also to be considered at the OA output port.

Most definitions of relevant single-channel parameters can be suitably extended to

multichannel applications. When this extension is straightforward, the word "channel" will be

added to the pertinent parameter. In particular, the noise figure and the signal-spontaneous

noise figure may be extended to multichannel applications, channel by channel, by

(λ) at each channel wavelength and the channel signal
considering the value of P
ASE

bandwidth. For each channel wavelength there will be a unique value of noise figure that will

be a function of the input power level of all signals. In this case the parameters, channel noise

figure and channel signal-spontaneous noise figure, are introduced. However, some additional

parameters also need to be defined. For each parameter, the particular multichannel

configuration, including the full set of channel signal wavelengths and input powers, needs to

be specified.

The parameters defined in 3.2.1 will in general depend on temperature and polarization state

of input channels. The temperature and state of polarization should be kept constant or

controlled or be measured and reported together with the measured parameter.

NOTE 2 Except where noted, the optical powers mentioned in 3.2.1 are intended as average powers.

NOTE 3 The measured optical powers are open beam powers: this can result in differences of about 0,18 dB in

the measurement of absolute power levels.

NOTE 4 In the case of the distributed amplifier, all the parameters are related to a suitable reference fibre used to

emulate the transmission fibre in conjunction with the pumping assembly.
3.2 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 60050-731 and

IEC TR 61931 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
---------------------- Page: 10 ----------------------
IEC 61291-1:2018 © IEC 2018 – 9 –
3.2.1 OA devices and distributed amplifiers

NOTE The terms and definitions in 3.2.1 also apply, in general, to optical amplifiers under

IEC 61290 (all parts) and IEC 61291 (all parts).
3.2.1.1
gain

increase of signal optical power from the output end of the jumper fibre to the OA output port

in an OA which is externally connected to an input jumper fibre

Note 1 to entry: The gain includes the connection loss between the input jumper fibre and the OA input port.

Note 2 to entry: It is assumed that the jumper fibres are of the same type as the fibres used as input and output

port of the OA.

Note 3 to entry: Care should be taken to exclude the amplified spontaneous emission power from the signal

optical powers.
Note 4 to entry: Gain is expressed in dB.
3.2.1.2
small-signal gain

gain of the amplifier, when operated in linear regime, where it is essentially independent of

the input signal optical power, at a given signal wavelength and pump optical power level

Note 1 to entry: This property can be described at a discrete wavelength or as a function of wavelength.

3.2.1.3
reverse gain
gain measured using the input port of the OA as output port and vice versa
3.2.1.4
reverse small-signal gain

small-signal gain measured using the input port of the OA as output port and vice versa

3.2.1.5
maximum gain

highest gain that can be achieved when the OA is operated within the stated nominal

operating conditions
3.2.1.6
maximum small-signal gain

highest small-signal gain that can be achieved when the OA is operated within the stated

nominal operating conditions
3.2.1.7
maximum gain wavelength
wavelength at which the maximum gain occurs
3.2.1.8
maximum small-signal gain wavelength
wavelength at which the maximum small-signal gain occurs
3.2.1.9
gain wavelength variation
peak-to-peak variation of the gain over a given wavelength range
3.2.1.10
small-signal gain wavelength variation
peak-to-peak variation of the small-signal gain over a given wavelength range
---------------------- Page: 11 ----------------------
– 10 – IEC 61291-1:2018 © IEC 2018
3.2.1.11
gain-slope under single wavelength operation

derivative of the gain of a small probe versus wavelength, at the

signal wavelength, in the presence of a signal of given wavelength and input power

Note 1 to entry: The probe total average power level shall be at least 20 dB below the input signal level, to

minimize the effect on the gain wavelength-profile.
3.2.1.12
polarization-dependent gain
PDG

the maximum variation of the OA gain due to a variation of the state of polarization of the

input signal, at nominal operating conditions

Note 1 to entry: A source of PDG in OAs is the polarization dependent loss of the passive components used

inside.
Note 2 to entry: This note applies to the French language only.
3.2.1.13
channel gain

gain for each channel (at wavelength λ) in a specified

multichannel configuration

Note 1 to entry: Channel gain, G , can be expressed as G = P – P , where P and P are respectively the input

j j oj ij ij oj

and output power levels, in dBm, of the j-th channel and j = 1, 2, … n; n total number of channels.

Note 2 to entry: Since the amplifier saturation power level is determined by the combined effect of the input

signals at all wavelengths, the channel gain is dependent on the input power level of all signals.

Note 3 to entry: Channel gain is expressed in dB.
3.2.1.14
multichannel gain variation
interchannel gain difference

difference between the channel gains of any two of the channels

in a specified multichannel configuration

Note 1 to entry: Multichannel gain variation can be expressed as ΔG = G – G , where G and G are respectively

jl j l j l
the channel gains of
...