SIST EN 61290-1-2:2006

SLOVENSKI STANDARD
SIST EN 61290-1-2:2006
01-marec-2006
Nadomešča:
SIST EN 61290-1-2:1999
SIST EN 61290-2-2:1999
Optični ojačevalniki – Preskusne metode – 1-2. del: Parametri moči in ojačenja –
Metoda z električnim spektralnim analizatorjem (IEC 61290-1-2:2005)
Optical amplifiers - Test methods -- Part 1-2: Power and gain parameters - Electrical
spectrum analyzer method
Prüfverfahren für Lichtwellenleiter-Verstärker -- Teil 1-2: Optische Leistungs- und
Verstärkerparameter - Verfahren mit elektrischem Spektralanalysator
Amplificateurs optiques - Méthodes d'essai -- Partie 1-2: Paramètres de puissance et de
gain - Méthode de l'analyseur de spectre électrique
Ta slovenski standard je istoveten z: EN 61290-1-2:2005
ICS:
33.180.30 Optični ojačevalniki Optic amplifiers
SIST EN 61290-1-2:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 61290-1-2:2006

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SIST EN 61290-1-2:2006
EUROPEAN STANDARD EN 61290-1-2
NORME EUROPÉENNE
EUROPÄISCHE NORM December 2005

ICS 33.100.99 Supersedes EN 61290-1-2:1998


English version


Optical amplifiers -
Test methods
Part 1-2: Power and gain parameters -
Electrical spectrum analyzer method
(IEC 61290-1-2:2005)


Amplificateurs optiques -  Prüfverfahren für
Méthodes d'essai Lichtwellenleiter-Verstärker
Partie 1-2: Paramètres de puissance Teil 1-2: Optische Leistungs-
et de gain - und Verstärkerparameter -
Méthode de l'analyseur Verfahren mit elektrischem
de spectre électrique Spektralanalysator
(CEI 61290-1-2:2005) (IEC 61290-1-2:2005)




This European Standard was approved by CENELEC on 2005-10-01. 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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom.

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

Central Secretariat: rue de Stassart 35, B - 1050 Brussels


© 2005 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 61290-1-2:2005 E

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SIST EN 61290-1-2:2006
EN 61290-1-2:2005 - 2 -
Foreword
The text of document 86C/672/FDIS, future edition 2 of IEC 61290-1-2, 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 was approved by CENELEC as EN 61290-1-2 on 2005-10-01.
This European Standard supersedes EN 61290-1-2:1998.
It includes the measurement of gain parameters previously covered in EN 61290-2-1. Also, the scope
of the measurement method has been broadened to include semiconductor optical amplifiers and
waveguide optical amplifiers in addition to optically-pumped fibre amplifiers.
This standard is to be read in conjunction with EN 61291-1.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2006-08-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2008-10-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61290-1-2:2005 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 60793-1-1 NOTE Harmonized as EN 60793-1-1:2003 (not modified).
IEC 60825-1 NOTE Harmonized as EN 60825-1:1994 (not modified).
IEC 60825-2 NOTE Harmonized as EN 60825-2:2004 (not modified).
IEC 60874-1 NOTE Harmonized as EN 60874-1:1999 (not modified).
IEC 61290-10-1 NOTE Harmonized as EN 61290-10-1:2003 (not modified).
IEC 61290-10-2 NOTE Harmonized as EN 61290-10-2:2003 (not modified).
IEC 61290-10-3 NOTE Harmonized as EN 61290-10-3:2003 (not modified).
__________

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SIST EN 61290-1-2:2006
- 3 - EN 61290-1-2:2005
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 Where an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
1) 2)
IEC 60793-1-40 - Optical fibres EN 60793-1-40 2003
(mod) Part 1-40: Measurement methods and
test procedures – Attenuation

3) 3)
IEC 61291-1 - Optical fibre amplifiers EN 61291-1 -
Part 1: Generic specification




1)
Undated reference.
2)
Valid edition at date of issue.
3)
To be published.

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SIST EN 61290-1-2:2006

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SIST EN 61290-1-2:2006
NORME CEI
INTERNATIONALE
IEC



61290-1-2
INTERNATIONAL


Deuxième édition
STANDARD

Second edition

2005-11


Amplificateurs optiques –
Méthodes d'essai –
Partie 1-2:
Paramètres de puissance et de gain –
Méthode de l'analyseur de spectre électrique

Optical amplifiers –
Test methods –
Part 1-2:
Power and gain parameters –
Electrical spectrum analyzer method

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Pour prix, voir catalogue en vigueur
For price, see current catalogue

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 3 –
CONTENTS

FOREWORD.5
INTRODUCTION.11

1 Scope.13
2 Normative references.15
3 Acronyms and abbreviations .15
4 Apparatus.15
5 Test sample.21
6 Procedure.21
7 Calculation .27
8 Test results .31

Bibliography .35

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

OPTICAL AMPLIFIERS – TEST METHODS –

Part 1-2: Power and gain parameters –
Electrical spectrum analyzer 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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 61290-1-2 Ed. 2.0 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 1998. It constitutes a
technical revision. This second edition includes the measurement of gain parameters
previously covered in IEC 61290-2-1 Ed. 1.0. Also, the scope of the measurement method has
been broadened to include semiconductor optical amplifiers and waveguide optical amplifiers in
addition to optically-pumped fibre amplifiers.
This standard is to be read in conjunction with IEC 61291-1.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 7 –
The text of this standard is based on the following documents:
FDIS Report on voting
86C/672/FDIS 86C/677/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
IEC 61290 consists of the following parts under the general title Optical amplifiers – Test
1)
methods:
Part 1-1: Test methods for gain parameters – Optical spectrum analyzer
Part 1-2: Power and gain parameters – Electrical spectrum analyzer method
Part 1-3: Power and gain parameters – Optical power meter method
Part 2-1: Test methods for optical power parameters – Optical spectrum analyzer
Part 2-2: Test methods for optical power parameters – Electrical spectrum analyzer
Part 2-3: Test methods for optical power parameters – Optical power meter
Part 3: Test methods for noise figure parameters
Part 3-1: Noise figure parameters – Optical spectrum analyzer method
Part 3-2: Test methods for noise figure parameters – Electrical spectrum analyzer method
Part 5-1: Test methods for reflectance parameters – Optical spectrum analyser
Part 5-2: Reflectance parameters – Electrical spectrum analyser method
Part 5-3: Test methods for reflectance parameters – Reflectance tolerance using electrical
spectrum analyser
Part 6-1: Test methods for pump leakage parameters – Optical demultiplexer
Part 7-1: Test methods for out-of-band insertion losses – Filtered optical power meter
Part 10-1: Multi-channel parameters – Pulse method using an optical switch and optical
spectrum analyzer
Part 10-2: Multi-channel parameters – Pulse method using a gated optical spectrum
analyzer
Part 10-3: Multi-channel parameters – Probe methods
Part 11-1: Polarization mode dispersion – Jones matrix eigenanalysis method (JME)
Part 11-2 : Polarization mode dispersion parameter – Poincaré sphere analysis method
___________
1)
The first editions of some of these parts were published under the general title Optical fibre amplifiers – Basic
specification or Optical amplifier test methods.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 9 –
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.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 11 –
INTRODUCTION
This International Standard is devoted to the subject of optical amplifiers. The technology of
optical amplifiers is still rapidly evolving, hence amendments and new editions to this standard
can be expected.
Each abbreviation introduced in this International 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 International Standard is given in Clause 3.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 13 –
OPTICAL AMPLIFIERS – TEST METHODS –

Part 1-2: Power and gain parameters –
Electrical spectrum analyzer method



1 Scope
This part of IEC 61290 applies to all commercially available optical amplifiers (OAs) and
optically amplified sub-systems. It applies to OAs using optically pumped fibres (OFAs based
on either rare-earth doped fibres or on the Raman effect), semiconductors (SOAs), and
waveguides (POWAs).
NOTE The applicability of the test methods described in the present standard to distributed Raman amplifiers is
for further study.
The object of this standard is to establish uniform requirements for accurate and reliable
measurements, by means of the electrical spectrum analyzer test method, of the following OA
parameters, as defined in Clause 3 of IEC 61291-1:
a) nominal output signal power
b) gain;
c) reverse gain;
d) maximum gain;
e) polarization-dependent gain;
f) large-signal output stability;
g) saturation output power;
h) maximum input signal power;
i) maximum output signal power;
j) input power range;
k) output power range;
l) maximum total output power.
In addition this test method provides a means for measuring the following parameters:
− maximum gain wavelength;
− gain wavelength band.
NOTE All numerical values followed by (‡) are suggested values for which the measurement is assured. Other
values may be acceptable, but should be verified.
The object of this standard is specifically directed to single-channel amplifiers. For
2
multichannel amplifiers, one should refer to the IEC 61290-10 series .
___________
2
See Bibliography.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 15 –
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 60793-1-40: Optical fibres – Part 1-40: Measurement methods and test procedures –
Attenuation
3
IEC 61291-1:2005 Optical amplifiers – Part 1: Generic specification
3 Acronyms and abbreviations
ASE amplified spontaneous emission
DBR distributed Bragg reflector (laser diode)
DFB distributed feedback (laser diode)
ECL external cavity laser (diode)
LED light emitting diode
OA optical amplifier
OFA optical fibre amplifier
POWA planar optical waveguide amplifier
SOA semiconductor optical amplifier
4 Apparatus
A diagram of the measurement set-up is given in Figure 1.
___________
3
 A first edition of IEC 61291-1 was published in 1998 under the title Optical fibre amplifiers – Part 1: Generic
specification.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 17 –

Optical
coupler
J1
Optical
Optical Polarisation
dB
power
source
controller
meter
Variable
optical
attenuator
Optical
Signal
power
generator
meter
IEC  1610/05
a) Average optical input signal power
Optical
coupler
J1 J2
Optical Polarisation Optical
dB
source controller detector
Variable
optical
attenuator
Optical
Electrical
Signal
power
spectrum
generator
meter
analyzer
IEC  1611/05
b) Electrical input signal power
Optical
coupler
J1
J2
Optical
Polarisation Optical
dB OA
source
detector
controller
Variable
optical OA
under test
attenuator
Optical
Signal
Electrical
power
generator
spectrum
meter
analyzer
IEC  1612/05
c) Electrical output signal power

Figure 1 – Typical arrangement of the electrical spectrum analyzer test apparatus for
measurement of (a) average optical input signal power, (b) electrical input signal power
and (c) electrical output signal power.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 19 –
The test equipment listed below, with the required characteristics, is needed.
a) Optical source: The optical source shall be either at fixed wavelength or wavelength-tunable.
– Fixed-wavelength optical source: This optical source shall generate a light with a
wavelength and optical power specified in the relevant detail specification. Unless
otherwise specified, the optical source shall emit modulated light with the full width at
half maximum of the spectrum narrower than 1 nm (‡). A distributed feedback (DFB)
laser, a distributed Bragg reflector (DBR) laser, an external cavity laser (ECL) diode and
a light-emitting diode (LED) with a narrow-band filter are applicable, for example. The
suppression ratio for the side modes for the DFB laser, the DBR laser or the ECL shall
be higher than 30 dB (‡). The output power fluctuation shall be less than 0,05 dB (‡),
which may be better attainable with an optical isolator at the output port of the optical
source. Spectral broadening at the foot of the lasing spectrum shall be minimal for laser
sources.
– Wavelength-tunable optical source: This optical source shall be able to generate a
wavelength-tunable light within the range specified in the relevant detail specification.
Its optical power shall be specified in the relevant detail specification. Unless otherwise
specified, the optical source shall emit modulated light with the full width at half
maximum of the spectrum narrower than 1 nm (‡). An ECL or an LED with a narrow
bandpass optical filter is applicable, for example. The suppression ratio of side modes
for the ECL shall be higher than 30 dB (‡). The output power fluctuation shall be less
than 0,05 dB, which may be better attainable with an optical isolator at the output port of
the optical source. Spectral broadening at the foot of the lasing spectrum shall be
minimal for the ECL.
NOTE The use of an LED should be limited to small-signal gain measurements.
b) Optical power meter: It shall have a measurement accuracy better than ±0,2 dB,
irrespective of the state of polarization, within the operational wavelength bandwidth of the
OA. A dynamic range exceeding the measured gain is required (e.g. 40 dB).
c) Electrical spectrum analyzer: The spectral-power-measurement error shall be better than
±0,5 dB (optical). The linearity shall be better than ±0,2 dB (optical).
d) Optical isolator: Optical isolators may be used to bracket the OA. The polarization-
dependent loss variation of the isolator shall be better than 0,2 dB (‡). Optical isolation shall
be better than 40 dB (‡). The reflectance from this device shall be smaller than –40 dB (‡) at
each port.
e) Variable optical attenuator: The attenuation range and stability shall be over 40 dB (‡) and
better than ±0,1 dB (‡), respectively. The reflectance from this device shall be smaller than
–40 dB (‡) at each port.
f) Polarization controller: This device shall be able to provide as input signal light all possible
states of polarization (e.g. linear, elliptical and circular). For example, the polarization
controller may consist of a linear polarizer followed by an all-fibre-type polarization
controller, or by a linear polarizer followed by a quarter-wave plate rotatable by minimum of
90° and a half wave plate rotatable by minimum of 180°. The loss variation of the
polarization controller shall be less than 0,2 dB (‡). The reflectance from this device shall
be smaller than –40 dB (‡) at each port. The use of a polarization controller is considered
optional, except for the measurement of polarization dependent gain, but may also be
necessary to achieve the desired accuracy of other power and gain parameters for OA
devices exhibiting significant polarization dependent gain.
g) Optical fibre jumpers: The mode field diameter of the optical fibre jumpers used should be
as close as possible to that of fibres used as input and output ports of the OA. The
reflectance from this device shall be smaller than –40 dB (‡) at each port, and the length of
the jumper shall be shorter than 2 m.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 21 –
h) Optical connectors: The connection loss repeatability shall be better than ±0,2 dB.
i) Optical detector: This device shall be highly polarization insensitive and have a linearity
better than ±0,2 dB.
NOTE In order to minimize the saturation effects due to high d.c. levels, the optical detector output shall be
a.c. coupled.
j) Signal generator: The signal generator shall generate a sinusoidal wave at a frequency
higher than several hundreds of kilohertz with a linearity better than ±1,5 dB.
NOTE For small-signal gain measurements an optical chopping system could be used alternatively.
k) Optical coupler: The polarization dependence of the branching ratio of the coupler shall be
minimal. Change of the state of polarization of the input light shall be negligible. Any free
port of the coupler shall be properly terminated, in such a way as to decrease the
reflectance below -40 dB (‡).
5 Test sample
The OA shall operate at nominal operating conditions. If the OA is likely to cause laser
oscillations due to unwanted reflections, optical isolators should be used to bracket the OA
under test. This will minimize the signal instability and the measurement inaccuracy.
For measurements of parameters a) to l) of Clause 1 except e), care shall be taken in
maintaining the state of polarization of the input light during the measurement. Changes in the
polarization state of the input light may result in input optical power changes, because of the
slight polarization dependency expected from all the optical components used, this leading to
measurement errors.
6 Procedure
The measurement procedure is as follows.
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 presence of changes in the state of
polarization and other instabilities, as specified in the relevant detail specification. The
measurement procedures described below shall be followed, with reference to Figure 1:
1) Set the optical source at the test wavelength specified in the relevant detail speci-
fication.
2) Measure the branching ratio of the optical coupler through the signal power levels
exiting the two output ports, with an optical power meter.
3) Measure the loss, L , of the optical fibre jumper between the OA and the optical detector
j
(see Figure 1c) by the insertion loss technique (see Method B, in IEC 60793-1-40).
4) Set the signal generator in a way that the light emitted by the optical source is intensity
modulated at the frequency specified in the detail specification. Unless otherwise
specified, the modulation frequency shall be higher than some hundred kilohertz (e.g.
1 MHz) to avoid waveform distortion due to slow gain response. The modulation depth
shall be unchanged during the measurement.

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SIST EN 61290-1-2:2006
61290-1-2  IEC:2005 – 23 –
5) For measuring optical powers with the electrical spectrum analyzer, the following
calibration procedure (of the electrical spectrum analyzer) is needed, using an optical
power meter:
– for calibration, set the time-averaged optical power P by using an optical power
cal
meter (see Figure 1a), as specified in the relevant detail specification;
– measure the a.c. component of the input signal electrical power P with the optical
e, cal
detector and the electrical spectrum analyzer;
– keeping the modulation depth unchanged during the measurement, the time-
averaged optical signal power P shall be derived from the a.c. component of the
corresponding signal electrical power P (measured with the electrical spectrum
e
analyzer) by:
P = P (/PP )
cal
ee, cal
6) Set the optical source and the variable optical attenuator in such a way as to provide,
at the input port of the OA, the time-averaged input optical signal power specified P
in
in the relevant detail specification. Record the time-averaged optical power P
o
measured with an optical power meter at the other (second) output port of the optical
coupler, as shown in Figure 1a.
7) Keep the time-averaged optical signal power at the OA input constant (P ) during the
in
following measurements, by monitoring the second output port of the coupler and, if
necessary, setting the variable optical attenuator in such a way that the time-averaged
optical power exiting the second output port of the optical coupler remains constant
(P ).
o
8) Set the polarization controller at a given state of polarization as specified in the
relevant detail specification, and monitor, by means of the electrical spectrum
analyzer the (time-averaged) optical signal power at the output of the OA for the
specified period of time, recording the minimum value.
9) Change the state of polarization of the input signal by means of the polarization
controller, trying to minimize the output optical signal power measure with the
electrical spectrum analyzer, and repeat Step 8).
10) Repeat procedure 9) for the different states of polarization indicated in the relev
...