IEC 61290-1:2022

Optical amplifiers - Test methods - Part 1: Power and gain parameters

IEC 61290-1:2022 is available as IEC 61290-1:2022 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61290-1:2022 applies to all commercially available optical amplifiers (OAs) and optically amplified subsystems. It applies to OAs using optically pumped fibres (optical fibre amplifiers (OFAs) based on either rare-earth doped fibres or on the Raman effect), semiconductors (semiconductor optical amplifiers (SOAs)), and aveguides (planar optical waveguide amplifiers (POWAs)). It is specifically directed to single-channel amplifiers. Test methods for multichannel amplifiers are defined in the IEC 61290-10 series. This document establishes uniform requirements for accurate and reliable measurements of the following OA parameters, as defined in IEC 61291-1:2018, Clause 3:
a) nominal output signal power;
b) gain;
c) reverse gain;
d) maximum gain;
e) maximum gain wavelength;
f) maximum gain variation with temperature;
g) gain wavelength band;
h) gain wavelength variation;
i) gain stability;
j) polarization-dependent gain;
k) gain ripple (SOA only);
l) large-signal output stability;
m) saturation output power;
n) maximum output signal power;
o) maximum total output power.
NOTE 1 The applicability of the test methods described in this document to distributed Raman amplifiers is still under study. NOTE 2 All numerical values followed by (‡) are suggested values for which the measurement is assured. Other values are acceptable if verified. This second edition cancels and replaces the first edition published in 2014. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- specification of gain ripple as a new parameter;
- specification of test method and test report for gain ripple measurements;
- use of the term “measurement uncertainty” instead of “measurement accuracy”.

Amplificateurs optiques - Méthodes d'essai - Partie 1: Paramètres de puissance et de gain

IEC 61290-1:2022 est disponible sous forme de IEC 61290-1:2022 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L'IEC 61290-1:2022 s’applique à tous les amplificateurs optiques (AO) et sous-systèmes à amplification optique, disponibles sur le marché. Elle s’applique aux AO utilisant des fibres pompées optiquement (amplificateurs à fibres optiques (AFO) basés sur des fibres dopées aux terres rares ou sur l’effet Raman), des semiconducteurs (amplificateurs optiques à semiconducteurs (SOA)), et des guides d’ondes (amplificateurs à guide d’ondes optiques planaires (POWA)). Elle est spécifiquement centrée sur les amplificateurs à un seul canal. Les méthodes d'essai pour les amplificateurs à canaux multiples sont définies dans la série IEC 61290-10.
Le présent document établit des exigences uniformes pour des mesures précises et fiables des paramètres d’AO donnés ci-dessous, tels qu’ils sont définis dans l'IEC 61291-1:2018, Article 3:
a) puissance nominale du signal de sortie;
b) gain;
c) gain inverse;
d) Gain maximal;
e) longueur d’onde du gain maximal;
f) variation maximale du gain en fonction de la température;
g) bande de longueur d’onde du gain;
h) variation du gain en fonction de la longueur d’onde;
i) stabilité du gain;
j) gain dépendant de la polarisation;
k) ondulation du gain (SOA uniquement);
l) stabilité de sortie grands signaux;
m) puissance de sortie en saturation;
n) puissance maximale du signal de sortie;
o) puissance de sortie totale maximale.
NOTE 1 L’applicabilité des méthodes d’essai décrites dans le présent document à des amplificateurs à effet Raman répartis est toujours à l'étude. NOTE 2 Toutes les valeurs numériques suivies de (‡) sont des valeurs suggérées, pour lesquelles la mesure est assurée. D’autres valeurs sont acceptables, à condition d'être vérifiées.
Cette deuxième édition annule et remplace la première édition parue en 2014. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- spécification de l’ondulation du gain en tant que nouveau paramètre;
- spécification de la méthode d’essai et du rapport d’essai pour les mesures d’ondulation du gain;
- utilisation du terme “incertitude de mesure” au lieu de “précision de mesure”.

General Information

• Status: Published
• Publication Date: 06-Jun-2022
• ICS: 33.180.30 - Optic amplifiers
• Technical Committee: SC 86C - Fibre optic systems and active devices
• Current Stage: PPUB - Publication issued
• Completion Date: 07-Jun-2022

Standards Content (sample)

IEC 61290-1
Edition 2.0 2022-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical amplifiers – Test methods –
Part 1: Power and gain parameters
Amplificateurs optiques – Méthodes d’essai –
Partie 1: Paramètres de puissance et de gain
IEC 61290-1:2022-06(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 61290-1
Edition 2.0 2022-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical amplifiers – Test methods –
Part 1: Power and gain parameters
Amplificateurs optiques – Méthodes d’essai –
Partie 1: Paramètres de puissance et de gain
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.30 ISBN 978-2-8322-2286-7

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 61290-1:2022 © IEC 2022
CONTENTS

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

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

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

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

3.1 Terms and definitions .............................................................................................. 6

3.2 Abbreviated terms ................................................................................................... 6

4 Optical power and gain test method ................................................................................. 6

5 Optical power and gain parameters ................................................................................. 6

6 Test results ................................................................................................................... 11

Bibliography .......................................................................................................................... 14

Figure 1 – Typical behaviour of the gain as a function of input signal power ........................... 7

Figure 2 – Typical behaviour of the gain as a function of wavelength ...................................... 7

Figure 3 – Typical behaviour of the gain as a function of temperature ..................................... 8

Figure 4 – Typical behaviour of the gain as a function of wavelength ...................................... 9

Figure 5 – Typical behaviour of the gain fluctuation as a function of time ................................ 9

Figure 6 – Typical behaviour of the output power fluctuation as a function of time ................ 10

Figure 7 – Typical behaviour of the gain as a function of input signal power ......................... 11

Figure 8 – Typical behaviour of the output power as a function of input signal power ............ 11

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IEC 61290-1:2022 © IEC 2022 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL AMPLIFIERS – TEST METHODS –
Part 1: Power and gain parameters
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

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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.

IEC 61290-1 has been prepared by subcommittee 86C: Fibre optic systems and active devices,

of IEC technical committee 86: Fibre optics. It is an International Standard.

This second edition cancels and replaces the first edition published in 2014. This edition

constitutes a technical revision.

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

edition:
a) specification of gain ripple as a new parameter;
b) specification of test method and test report for gain ripple measurements;
c) use of the term “measurement uncertainty” instead of “measurement accuracy”.
---------------------- Page: 5 ----------------------
– 4 – IEC 61290-1:2022 © IEC 2022
The text of this International Standard is based on the following documents:
Draft Report on voting
86C/1746/FDIS 86C/1783/RVD

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

described in greater detail at www.iec.ch/publications.

A list of all parts in 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 document will remain unchanged until the

stability date indicated on the IEC website under 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 61290-1:2022 © IEC 2022 – 5 –
OPTICAL AMPLIFIERS – TEST METHODS –
Part 1: Power and gain parameters
1 Scope

This part of IEC 61290 applies to all commercially available optical amplifiers (OAs) and

optically amplified subsystems. It applies to OAs using optically pumped fibres (optical fibre

amplifiers (OFAs) based on either rare-earth doped fibres or on the Raman effect),

semiconductors (semiconductor optical amplifiers (SOAs)), and waveguides (planar optical

waveguide amplifiers (POWAs)). It is specifically directed to single-channel amplifiers. Test

methods for multichannel amplifiers are defined in the IEC 61290-10 series.

This document establishes uniform requirements for accurate and reliable measurements of the

following OA parameters, as defined in IEC 61291-1:2018, Clause 3:
a) nominal output signal power;
b) gain;
c) reverse gain;
d) maximum gain;
e) maximum gain wavelength;
f) maximum gain variation with temperature;
g) gain wavelength band;
h) gain wavelength variation;
i) gain stability;
j) polarization-dependent gain;
k) gain ripple (SOA only);
l) large-signal output stability;
m) saturation output power;
n) maximum output signal power;
o) maximum total output power.

NOTE 1 The applicability of the test methods described in this document to distributed Raman amplifiers is still

under study.

NOTE 2 All numerical values followed by (‡) are suggested values for which the measurement is assured. Other

values are acceptable if verified.
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 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
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– 6 – IEC 61290-1:2022 © IEC 2022

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

Optical power meter method
IEC 61291-1:2018, Optical amplifiers – Part 1: Generic specification
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 61291-1 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
3.2 Abbreviated terms
ASE amplified spontaneous emission
FWHM full width at half maximum
OA optical amplifier
OFA optical fibre amplifier
OSA optical spectrum analyzer
POWA planar optical waveguide amplifier
SOA semiconductor optical amplifier
4 Optical power and gain test method

One of the three test methods described in IEC 61290-1-1, IEC 61290-1-2, and IEC 61290-1-3

for quantifying the optical power and gain of an OA shall be followed in this document.

The test method described in IEC 61290-1-1 determines the optical power and gain by means

of an optical spectrum analyzer.

The test method described in IEC 61290-1-2 determines the optical power and gain by means

of an optical detector and an electrical spectrum analyzer.

The test method described in IEC 61290-1-3 determines the optical power and gain by means

of an optical power meter and an optical bandpass filter.
5 Optical power and gain parameters
The parameters listed below are required for gain and power:

a) Nominal output signal power: The nominal output signal power is given by the minimum

output signal optical power for an input signal optical power specified in the relevant detail

specification and under nominal operating conditions given in the relevant detail

specification. To find this minimum value, input and output signal power levels shall be

continuously monitored for a given duration of time and in the presence of changes in the

state of polarization and other instabilities, as specified in the relevant detail specification.

The measurement procedures and calculations are described in each test method.

b) Gain: The measurement procedures and calculations are described in each test method.

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IEC 61290-1:2022 © IEC 2022 – 7 –

c) Reverse gain: As in b), but with the OA operating with the input port used as an output port

and vice-versa.

d) Maximum gain: As in b), but use a wavelength-tuneable optical source and repeat all

procedures at different wavelengths in such a way as to cover the wavelength range

specified in the relevant detail specification.

Unless otherwise specified, the wavelength should be changed by steps smaller than 1 nm

(‡) around the wavelength where the ASE spectral profile, observed (e.g. with an optical

spectrum analyzer or a monochromator) without the input signal, takes its maximum value.

NOTE 1 A wavelength measurement uncertainty of 0,01 nm, within the operating wavelength range of the OA,

is attainable with commercially available wavelength meters based on interference-fringes counting techniques.

Some tuneable external-cavity laser-diode instruments provide a wavelength measurement uncertainty of

0,2 nm.

The gain values are measured at the different wavelengths as described in b) above. The

maximum gain shall be given by the highest of all these gain values at nominal operating

condition. Figure 1 shows the typical behaviour of the gain as a function of the input signal

power.
Figure 1 – Typical behaviour of the gain as a function of input signal power

e) Maximum gain wavelength: As in d), the maximum gain wavelength shall be the wavelength

at which the maximum gain occurs. Refer to Figure 2 for typical gain behaviour for different

wavelengths.
Figure 2 – Typical behaviour of the gain as a function of wavelength

f) Maximum gain variation with temperature: The maximum change of signal gain for a certain

specified temperature range. The measurement procedures and calculations described

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– 8 – IEC 61290-1:2022 © IEC 2022

below shall be followed, with reference to the measurement set-up and procedure for each

test method:
1) as described in b), measure the maximum gain G within the variation of
max-tmp
temperature, as specified in the relevant detail specification;
2) as described in b), measure the minimum gain G within the variation of
min-tmp
temperature, as specified in the relevant detail specification;
3) the maximum gain variation with temperature ∆G is given by Formula (1):
tmp
∆G = G – G (dB) (1)
tmp max-tmp min-tmp
Refer to Figure 3.

The gain variation with temperature can depend on the signal wavelength, owing to its

active fibre characteristics. The wavelength at which the parameter is specified and

measured should be stated.
Figure 3 – Typical behaviour of the gain as a function of temperature

g) Gain wavelength band: Measure the maximum gain as described in d). Identify those

wavelengths at which the gain is N dB below the maximum gain. The gain wavelength band

shall be given by the wavelength interval(s) that comprise(s) those wavelengths at which

the gain is between the maximum gain value and the value N dB below the maximum gain.

Calculations are processed according to the following procedure:

1) plot the gain at each wavelength as a function of wavelength, as shown in Figure 2;

2) draw a horizontal line N dB below the maximum gain value;

3) the two or more intersection points of this line with the gain profile plotted in 1) yield two

(or more) N dB-down wavelengths, which define the range of the gain wavelength band.

The wavelength interval with the minimum difference in N dB-down wavelengths is the

gain wavelength band.
NOTE 2 A value of N = 3 is typically applied.

h) Gain wavelength variation: Measure the maximum gain and minimum gain over the specified

measurement wavelength range as described in d). The gain variation shall be the difference

between the maximum and the minimum gain values. Calculations are processed according

to the following procedure:
1) plot the gain of each wavelength as shown in Figure 4;
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IEC 61290-1:2022 © IEC 2022 – 9 –
2) find the maximum gain, G (dB) within the specified wavelength band;
max-λ
3) find the minimum gain, G (dB) within the specified wavelength band;
min-λ
4) calculate the gain wavelength variation, ∆G (dB) from Formula (2):
∆G = G – G (dB)
(2)
λ max-λ min-λ
Figure 4 – Typical behaviour of the gain as a function of wavelength

i) Gain stability: The maximum degree of gain fluctuation of the maximum and minimum signal

gain for a certain specified test period, as specified in the relevant detail specification. The

measurement procedure and calculations described below shall be followed with reference

to the measurement set-up for each test method. Refer to Figure 5 for typical behaviour of

the gain fluctuation:
1) as for b), measure the maximum gain G for a certain specified test period, as
max-stability
specified in the relevant detail specification;
2) as for b), measure the minimum gain G for a certain specified test period, as
min-stability
specified in the relevant detail specification;
3) the gain stability ∆G (dB) is given by Formula (3):
stability
∆G = G – G (dB)
(3)
stability max-stability min-stability
Figure 5 – Typical behaviour of the gain fluctuation as a function of time

j) Polarization-dependent gain: Gain values at the different states of polarization as described

in b). The procedure and calculations are described in each test method.
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– 10 – IEC 61290-1:2022 © IEC 2022

k) Gain ripple: Details of the measurement procedures and calculations are described in

IEC 61290-1-1.

l) Large-signal output stability: The maximum degree of gain fluctuation of the maximum and

minimum output optical power for a certain specified test period, as specified in the relevant

detail specification. The measurement procedure and calculations described below shall be

followed, with reference to the measurement set-up for each test method. Refer to Figure 6

for typical behaviour of the output power fluctuation:
1) as described in a), measure the maximum output signal power
P for a certain specified test period at a given wavelength and maximum signal
max-stability
input power, as specified in the relevant detail specification;
2) as described in a), measure the minimum output signal power
P for a certain specified test period at a given wavelength and maximum signal
min-stability
input power, as specified in the relevant detail specification;
3) compare P with P , and subtract P from P to
max-stability min-stability min-stability max-stability
obtain the large signal output stability;
4) large-signal output stability ∆P (dB) is given by Formula (4):
stability
∆P = P – P (dB)
(4)
stability max-stability min-stability

Figure 6 – Typical behaviour of the output power fluctuation as a function of time

m) Saturation output power: The measurement procedure described below shall be followed

with reference to the measurement set-up for each test method. The saturation output power

shall be given by the output power at which the gain is reduced by N dB (typically N = 3)

with respect to the small-signal gain at the same signal wavelength. Calculations are

processed according to the following procedure:

1) plot the gain versus input power as described in d). Refer to Figure 7 for typical

behaviour of the gain;

2) plot the output power versus input power. Refer to Figure 8 for typical behaviour of the

output power;

3) find the gain G (dB) which is N dB smaller than the small signal gain G in the linear

sat max
gain region (see Figure 7);
4) find the input power P (dBm) that produces the gain G ;
in-sat sat
(dBm) at the input power P (see Figure 8);
5) find the output power P
out-sat in-sat
6) P is the saturation output power.
out-sat
NOTE 3 A value of N = 3 is typically applied.
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IEC 61290-1:2022 © IEC 2022 – 11 –
Figure 7 – Typical behaviour of the gain as a function of input signal power

Figure 8 – Typical behaviour of the output power as a function of input signal power

n) Maximum output signal power: The measurement procedure and calculations are described

in each test method.

o) Maximum total output power: The measurement procedure and calculations are described

in each test method.
6 Test results
The following information and data shall be recorded in the test results.
a) Nominal optical signal power:
1) arrangement of the test set-up;
2) spectral linewidth (FWHM) of the optical source;
---------------------- Page: 13 ----------------------
– 12 – IEC 61290-1:2022 © IEC 2022

3) indication of the optical pump power and possibly driving current of pump lasers for

OFAs, and injection current for SOAs (if applicable);
4) operating temperature (if required);
5) input signal optical power, P ;
6) time-averaged input signal power (if applicable);
7) resolution bandwidth of the optical spectrum analyzer (if applicable);
8) resolution bandwidth of the electrical spectrum analyzer (if applicable);
9) FWHM of the optical bandpass filter (if applicable);
10) central wavelength of the optical bandpass filter (if applicable);
11) wavelength of the measurement;
12) nominal optical signal power levels, P;
13) change in the state of polarization given to the input signal light.

b) Gain: Items 1) to 11) listed for nominal optical signal power levels shall be presented and:

12) gain.

Items 5) and 12) may be replaced with the gain versus input optical signal power curve.

c) Reverse gain: Items 1) to 11) listed for gain shall be presented and:
12) reverse gain.

Items 5) and 12) may be replaced with the reverse gain versus input optical signal power

curve.
d) Maximum gain: Items 1) to 11) listed for gain shall be presented and:
12) wavelength range of the measurement;
13) maximum gain.

Items 5) and 13) may be replaced with the maximum gain versus input optical signal power

curve.

e) Maximum gain wavelength: Items 1) to 11) listed for gain shall be presented and:

12) wavelength range of the measurement;
13) wavelength measurement uncertainty;
14) maximum gain wavelength.

Items 12) and 14) may be replaced with the gain versus input signal wavelength curve.

f) Maximum gain variation with temperature: Items 1) to 11) listed for gain shall be presented

and:
12) the maximum and minimum gain with temperature, G and G
max-tmp min-tmp:
13) maximum gain variation with temperature.
g) Gain wavelength band: Items 1) to 11) listed for gain shall be presented and:
12) wavelength range of the measurement;
13) wavelength measurement uncertainty;
14) gain wavelength band;
15) N value chosen for the determination of the wavelength bandwidth.

Items 12), 14) and 15) may be replaced with the gain versus input signal wavelength curve.

h) Gain wavelength variation: Items 1) to 11) listed for gain shall be presented and:

12) wavelength range of the measurement;
13) wavelength measurement uncertainty of the optical spectrum analyzer;
14) gain variation.

Items 12) and 14) may be replaced with the gain versus input signal wavelength curve.

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IEC 61290-1:2022 © IEC 2022 – 13 –
i) Gain stability: Items 1) to 11) listed for gain shall be presented and:
12) the maximum and minimum gain, G and G ;
max-stability min-stability
13) gain stability.

j) Polarization-dependent gain: Items 1) to 11) listed for gain shall be presented and:

12) polarization dependency of the apparatus for detecting optical power for each test

method;
13) maximum and minimum gain, G and G ;
max-pol min-pol
14) polarization-dependent gain;
15) change in the state of polarization given to the input signal light.
k) Gain ripple:
The following items shall be presented:
1) arrangement of the test
...