EN 61300-3-7:2012

SLOVENSKI STANDARD
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Fibre optic interconnecting devices and passive components - Basic test and
measurement procedures - Part 3-7: Examinations and measurements - Wavelength
dependence of attenuation and return loss of single mode components (IEC 61300-3-
7:2009, Modified)
Lichtwellenleiter - Verbindungselemente und passive Bauteile - Grundlegende Prüf- und
Messverfahren - Teil 3-7: Untersuchungen und Messungen - Wellenlängenabhängigkeit
von Dämpfung und Rückflussdämpfung von Einmodenbauteilen (IEC 61300-3-7:2009,
modifiziert)
Dispositifs d’interconnexion et composants passives à fibres optiques - Méthodes
fondamentales d’essais et de mesures - Partie 3-7: Examens and mesures -
Affaiblissement et affaiblissement de réflexion en fonction de la longueur d’onde des
composants en unimodal (CEI 61300-3-7:2009, modifeé)
Ta slovenski standard je istoveten z: EN 61300-3-7:2012
ICS:
33.180.20 3RYH]RYDOQHQDSUDYH]D Fibre optic interconnecting
RSWLþQDYODNQD devices
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 61300-3-7
NORME EUROPÉENNE
January 2012
EUROPÄISCHE NORM
ICS 33.180.20 Supersedes EN 61300-3-5:2001, EN 61300-3-7:2001

English version
Fibre optic interconnecting devices and passive components -
Basic test and measurement procedures -
Part 3-7: Examinations and measurements -
Wavelength dependence of attenuation and return loss of single mode
components
(IEC 61300-3-7:2009, modified)

Dispositifs d’interconnexion et Lichtwellenleiter -
composants passives à fibres optiques - Verbindungselemente und passive
Méthodes fondamentales d’essais et de Bauteile -
mesures - Grundlegende Prüf- und Messverfahren -
Partie 3-7: Examens and mesures - Teil 3-7: Untersuchungen
Affaiblissement et affaiblissement de und Messungen -
réflexion en fonction de la longueur d’onde Wellenlängenabhängigkeit von Dämpfung
des composants en unimodal und Rückflussdämpfung von
(CEI 61300-3-7:2009, modifiée) Einmodenbauteilen
(IEC 61300-3-7:2009, modifiziert)

This European Standard was approved by CENELEC on 2011-12-07. 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 CEN-CENELEC Management Centre 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 CEN-CENELEC Management Centre 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, Turkey 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

© 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61300-3-7:2012 E
Foreword
This document (EN 61300-3-7:2012) consists of the text of IEC 61300-3-7:2009 prepared by SC 86B, "Fibre
optic interconnecting devices and passive components", of IEC/TC 86, "Fibre optics", together with the
common modifications prepared by CLC/TC 86BXA "Fibre optic interconnect, passive and connectorised
components".
The following dates are fixed:
• latest date by which this document has to be (dop) 2012-09-07
implemented
at national level by publication of an identical
national standard or by endorsement
(dow) 2012-12-07
• latest date by which the national standards conflicting
with this document have to be withdrawn

This document supersedes EN 61300-3-7:2001 + EN 61300-3-5:2001.

Changes from EN 61300-3-7:2001 are to reflect changes made to EN 61300-1 and covers unidirectional and
bi-directional methods of measurement.

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 61300-3-7:2009 was approved by CENELEC as a European
Standard with common modifications.
COMMON MODIFICATIONS
1 Modification to 4.1, General description
nd
Replace the 2 paragraph with the following:
"Invert the DUT in order to perform a bidirectional measurement. The measurements taken in both directions
shall be averaged. No averaging shall be done when the device is intentionally non-bidirectional.".
2 Modification to 6.1.1.3, Bidirectional measurement
Replace the entire subclause with the following:
"Invert the DUT in order to perform a bidirectional measurement. The measurements taken in both directions
shall be averaged. No averaging shall be done when the device is intentionally non-bidirectional.".
3 Modification to 6.1.2.2, Return loss measurement
Add as last paragraph the following:
"Note that the optical output power and reference power must not be equal.".

- 3 - EN 61300-3-7:2012
4 Modification to 6.1.2.3, Bidirectional measurement
Replace the entire subclause with the following:
"Invert the DUT in order to perform a bidirectional measurement. The measurements taken in both directions
shall be averaged. No averaging shall be done when the device is intentionally non-bidirectional.".
5 Modification to 6.1.3.3, Bidirectional measurement
Replace the entire subclause with the following:
"Invert the DUT in order to perform a bidirectional measurement. The measurements taken in both directions
shall be averaged. No averaging shall be done when the device is intentionally non-bidirectional.".
6 Modification to 6.3.1.3, Bidirectional measurement
Replace the entire subclause with the following:
"Invert the DUT in order to perform a bidirectional measurement. The measurements taken in both directions
shall be averaged. No averaging shall be done when the device is intentionally non-bidirectional.".
7 Modification to 6.3.2.3, Bidirectional measurement
Replace the entire subclause with the following:
"Invert the DUT in order to perform a bidirectional measurement. The measurements taken in both directions
shall be averaged. No averaging shall be done when the device is intentionally non-bidirectional.".
8 Modification to 6.3.3.2, Bidirectional measurement
Replace the entire subclause with the following:
"Invert the DUT in order to perform a bidirectional measurement. The measurements taken in both directions
shall be averaged. No averaging shall be done when the device is intentionally non-bidirectional.".

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 61300-3-29 - Fibre optic interconnecting devices and passive EN 61300-3-29 -
components - Basic test and measurement
procedures -
Part 3-29: Examinations and measurements -
Measurement techniques for characterising the
amplitude of the spectral transfer function of
DWDM components
IEC 62074-1 - Fibre optic interconnecting devices and passive EN 62074-1 -
components - Fibre optic WDM devices -
Part 1: Generic specification
IEC 61300-3-7
Edition 2.0 2009-01
INTERNATIONAL
STANDARD
Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures –
Part 3-7: Examinations and measurements – Wavelength dependence of
attenuation and return loss of single mode components

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
U
ICS 33.180.20 ISBN 978-2-88910-498-7
– 2 – 61300-3-7 © IEC:2009(E)
CONTENTS
FOREWORD.4
1 Scope.6
2 Normative references .6
3 Abbreviations and acronyms.6
4 General .8
4.1 General description .8
4.2 Spectral conditions.9
4.3 Definition.9
4.3.1 Attenuation .9
4.3.2 Return loss .10
4.4 Device under test .10
4.5 Measurement methods .11
4.5.1 Method A – Broadband light source (BBS).11
4.5.2 Method B – Tuneable narrowband light source (TLS).12
4.5.3 Method C – Set of multiple fixed narrowband light sources (NLS) .12
4.5.4 Method D – Tuneable OTDR.13
4.5.5 Reference method .13
5 Apparatus.13
5.1 Wavelength source.13
5.1.1 Method A – Broadband light source .13
5.1.2 Method B – Tuneable narrowband light source .13
5.1.3 Method C – Set of N narrowband light sources .14
5.1.4 Method D – Tuneable OTDR.14
5.1.5 Depolarizer.14
5.2 Detection system.15
5.2.1 Method A, Method B.2 and Method C.2 tuneable narrowband
detection spectrum .15
5.2.2 Method B.1 and Method C.1 broadband detection spectrum .15
5.3 Branching devices .15
5.4 Termination .16
6 Procedure .16
6.1 Method A – broadband light source .16
6.1.1 Attenuation-only .16
6.1.2 Return-loss-only .17
6.1.3 Attenuation and return loss.18
6.2 Method B – Tuneable narrowband light source .19
6.3 Method C – Set of multiple fixed narrowband light sources .20
6.3.1 Attenuation-only .20
6.3.2 Return-loss-only .22
6.3.3 Attenuation and return loss.23
6.4 Test results .25
7 Details to be specified .25
7.1 Source .25
7.1.1 Broadband source .25
7.1.2 Tuneable or discrete narrowband light source.26
7.1.3 Depolarizer.26

61300-3-7 © IEC:2009(E) – 3 –
7.2 Detection system.26
7.2.1 Optical power meter .26
7.2.2 Optical spectrum analyser .26
7.3 Reference branching device .26
7.4 Termination .26
Annex A (informative) Device under test configurations, terminations and product
types .27
Annex B (informative) Typical light source characteristics.29

Figure 1 – Wavelength dependence of attenuation and return loss .10
Figure 2 – Method A – Attenuation-only measurement .17
Figure 3 – Method A – Return-loss-only measurement .18
Figure 4 – Method A – Attenuation and return loss measurement.19
Figure 5 – Method C – Attenuation-only measurement .21
Figure 6 – Method C Return-loss-only measurement.22
Figure 7 – Method C – Attenuation and return loss measurement .24
Figure 8 – Wavelength dependent attenuation .25

Table 1 – Test methods and characteristics .11
Table 2 – Wavelength dependent attenuation and return loss .25
Table A.1 – Device under test configurations/terminations .27
Table A.2 – Possible types of passive optical components (POC) .27
Table B.1 – Types of broadband light source (BBS) and main characteristics .29
Table B.2 – Types of tuneable light source (TLS) and main characteristics .30

– 4 – 61300-3-7 © IEC:2009(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC INTERCONNECTING DEVICES
AND PASSIVE COMPONENTS –
BASIC TEST AND MEASUREMENT PROCEDURES –

Part 3-7: Examinations and measurements –
Wavelength dependence of attenuation
and return loss of single mode components

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 61300-3-7 has been prepared by subcommittee 86B: Fibre optic
interconnecting devices and passive components, of IEC technical committee 86: Fibre optics.
This second edition cancels and replaces the first edition published in 2000. It constitutes a
technical revision.
Changes from the previous edition of this standard are to reflect changes made to IEC 61300-
1 and covers unidirectional and bi-directional methods of measurement.

61300-3-7 © IEC:2009(E) – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
86B/2771/FDIS 86B/2803/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.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of IEC 61300 series, published under the general title, Fibre optic
interconnecting devices and passive components – Basic test and measurement procedures,
can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this standard may be issued at a later date.

– 6 – 61300-3-7 © IEC:2009(E)
FIBRE OPTIC INTERCONNECTING DEVICES
AND PASSIVE COMPONENTS –
BASIC TEST AND MEASUREMENT PROCEDURES –

Part 3-7: Examinations and measurements –
Wavelength dependence of attenuation
and return loss of single mode components

1 Scope
This part of IEC 61300-3 describes the various methods available to measure the wavelength
dependence of attenuation A(λ) and return loss RL(λ), of single-mode passive optical
components (POC) used in fibre-optic (FO) telecommunications. It is not, however, applicable
to dense wavelength division multiplexing (DWDM) devices. Measurement methods of
wavelength dependence of attenuation of DWDM devices are described in IEC 61300-3-29.
Definition of WDM device types is given in IEC 62074-1.
Three measurement cases are herein considered:
• Measurement of A(λ) only;
• Measurement of RL(λ) only;
• Measurement of A(λ) and RL(λ) at the same time.
These measurements may be performed in one direction (unidirectional) or bi-directionally.
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 (including any amendments) applies.
IEC 61300-3-29, Fibre optic interconnecting devices and passive components – Basic test
and measurement procedures – Part 3-29: Examinations and measurements – Measurement
techniques for characterising the amplitude of the spectral transfer function of DWDM
components
IEC 62074-1, Fibre optic WDM devices – Part 1: Generic specification
3 Abbreviations and acronyms
For the purposes of this document, the following abbreviations and acronyms apply:
A attenuation
A(λ) wavelength dependent attenuation
ASE amplified spontaneous emission
BBD broadband detection
BBS broadband source
61300-3-7 © IEC:2009(E) – 7 –
BD branching devices
CWDM coarse wavelength division multiplexing
DFB distributed feedback (laser)
DOP degree of polarization
DUT device under test
DWDM dense wavelength division multiplexing
DWS discrete wavelength source
ECL external cavity (tuneable) laser
EDFL erbium-doped fibre laser
FA fibre amplifier
FP Fabry-Perot (laser)
G(λ) test system constant
IL insertion loss
IL(λ) wavelength dependent insertion loss
λ wavelength
NLS narrowband light sources
OPM optical power meter
OSA optical spectrum analyser
P (λ) wavelength dependent power incident on the DUT
i
P (λ) wavelength dependent power reflected by the DUT (from the input port of the DUT)
r
P (λ) wavelength dependent power transmitted through the DUT
t
RL
P ( λ ) wavelength dependent reflected power measured for the determination of the test
G
set-up constant
RL
P (λ ) wavelength dependent incident power measured for the determination of the test
Gi
set-up constant
A
P (λ ) wavelength dependent power incident on the DUT in case of the wavelength
i
dependent attenuation measurement

– 8 – 61300-3-7 © IEC:2009(E)
RL
P (λ ) wavelength dependent power incident on the DUT in case of the wavelength
i
dependent return loss measurement
PDL polarization dependent loss
POC passive optical components
PON passive optical network
RBD reference branching device
RBW resolution bandwidth
RL return loss
RL(λ) wavelength dependent return loss
RTM reference test method
SMSR side mode suppression ratio
SOA semiconductor amplifier
SOP state of polarization
T termination
TJ temporary joint
TND tuneable narrowband detection (system)
TLS tuneable narrowband light source
TN-OTDR tuneable OTDR
WDM wavelength division multiplexing
4 General
4.1 General description
A(λ) and RL(λ) are expressed in decibels (dB), transmitted by or reflected from a device
under test (DUT) resulting from its insertion within a fibre-optic (FO) telecommunication
system. A(λ) and RL(λ) are obtained by comparing the optical power incident on the DUT with
the optical power
• transmitted at the output port of the DUT;
• reflected from the input port of the DUT.
The DUT is inverted in order to get a bi-directional measurement. Measurements should be
taken in both directions and averaged expect where the device is intentionally not
bidirectional no averaging shall be done.
The term “return loss” should not be used as equivalent to reflectance. Both have completely
different meanings.
61300-3-7 © IEC:2009(E) – 9 –
4.2 Spectral conditions
A(λ) and RL(λ) measurements are made over a wavelength range defined in the DUT
specifications. The DUT spectral characteristics also defined in the DUT specifications should
be used in turn to define the spectral characteristics of the measurement system, such as its
wavelength resolution (spectral difference between two adjacent data points) and uncertainty
(spectral uncertainty around each data point) which in turn will define the bandwidth of the
measurement system.
4.3 Definition
4.3.1 Attenuation
A(λ) refers to the power decrease of light transmitted by the DUT as a function of wavelength.
It is expressed as follows:
⎡ P()λ ⎤
t
[dB] (1)
A( λ ) = − 10 × log
⎢ ⎥
P()λ
⎣ i ⎦
where
P (λ) is the optical power, as a function of wavelength, transmitted through the input
t
port of the DUT and measured at the output port of the DUT, expressed in watt;
P (λ) is the optical power, as a function of wavelength, incident on and measured at
i
the input port of the DUT, expressed in watt;
for bi-directional measurement,
P (λ) is the optical power, as a function of wavelength, transmitted through the output
t
port of the DUT and measured at the input port of the DUT, expressed in watt;
P (λ) is the optical power, as a function of wavelength, incident on and measured at
i
the output port of the DUT, expressed in watt.
Figure 1 illustrates the process.

– 10 – 61300-3-7 © IEC:2009(E)

Port A Port B
DUT
Incident spectrum P(λ)
i Transmitted spectrum P (λ)
t
Input
Output
a) Unidirectional measurement
Incident spectrum P(λ)
i
Transmitted spectrum P (λ)
t
Reflected spectrum P (λ)
r
Port B
DUT Output
Port A
/Input Incident spectrum P(λ)
i
Transmitted spectrum P (λ)
t
Reflected spectrum P (λ)
r
b) Bi-directional measurement
IEC  2334/08
Figure 1 – Wavelength dependence of attenuation and return loss
4.3.2 Return loss
RL(λ) refers to the power decrease of light reflected by the DUT as a function of wavelength.
It is expressed as follows:
⎡ P()λ ⎤
r
RL(λ ) = − 10 × log [dB] (2)
⎢ ⎥
P()λ
⎣ i ⎦
where
P (λ) is the optical power, as a function of wavelength, reflected by and measured from
r
the input port of the DUT, expressed in watt;
P (λ) is the optical power, as a function of wavelength, incident on and measured at
i
the input port of the DUT, expressed in watt;
for bi-directional measurement,
P (λ) is the optical power, as a function of wavelength, reflected by and measured from
r
the output port of the DUT, in units of W;
P (λ) is the optical power, as a function of wavelength, incident on and measured at
i
the output port of the DUT, in units of W.
Figure 1 illustrates the process.
4.4 Device under test
The DUT may have more than two ports. However, since measurement of A(λ) is made across
only two ports, be they unidirectional or bi-directional, the DUT in this standard shall be

61300-3-7 © IEC:2009(E) – 11 –
described as having two ports. The same is true for measurement of RL(λ), except that in this
case, the measurement is made from only one port at a time.
Eight different DUT configurations are herein considered and described in Table B.1 of
Annex B. The differences between these configurations are primarily in the terminations of the
optical ports. Terminations may consist of bare fibre, connector plug, or receptacle. The
various types of product that are herein under consideration are illustrated in Table B.2 of
Annex B.
4.5 Measurement methods
The characterization of the DUT spectral response can be carried out on several discrete
wavelengths along a wavelength range of interest, continuously over the range or a
combination of the above. The way this characterization is performed defines the various test
methods.
Four methods, A to D, are described for measuring A(λ) and RL(λ). The methods are listed
below in the order of their introduction. For some methods, multiple configurations are
possible.
Table 1 summarizes the different test methods and their main characteristics.
NOTE Different test configurations and methods will result in different accuracies of the attenuation being
measured. In cases of dispute, the RTM should be used.
Table 1 – Test methods and characteristics
Method Name Light source Detection Example Comments
system
A BBS BBS TND BBS + DUT + OSA Alternate
B TLS To be depolarised +
coherence control
B.1 TLS + BBD TLS BBD TLS + DUT + OPM
B.1.1 TLS in start-stop-measure TLS in start-stop- BBD TLS + DUT + OPM Alternate
mode + BBD measure mode
B.1.2 TLS in sweep mode + BBD TLS in sweep mode BBD TLS + DUT + OPM Alternate
B.2 TLS + TND TLS TND TLS + DUT + OSA
B.2.1 TLS in start-stop-measure TLS in start-stop- TND TLS + DUT + OSA RTM
mode + TND measure mode
B.2.2 TLS in sweep mode + TND TLS in sweep mode TND TLS + DUT + OSA Alternate
C Set of N NLS To be depolarised +
coherence control
C.1 N NLS + BBD N NLS BBD N NLS + N x 1 coupler + Alternate
DUT + OPM
C.2 N NLS + TND N NLS TND N NLS + N x 1 coupler + Alternate
DUT + OSA
D TN-OTDR TN OTDR TN-OTDR TN-OTDR + DUT Alternate

4.5.1 Method A – Broadband light source (BBS)
In Method A, a broadband light source (BBS) is used with a tuneable narrowband filtering
detection system (TND).
A possible implementation of Method A is the use of the BBS with an optical spectrum
analyser (OSA). Method A has the advantage of providing all the required wavelength range

– 12 – 61300-3-7 © IEC:2009(E)
in a single test and the test sampling rate is defined by the TND. Measurement of the
wavelength dependence should be done using the BBS having high quality spectral power density.
Use of a suitable TND spectral filter is recommended for an accurate measurement.
4.5.2 Method B – Tuneable narrowband light source (TLS)
In Method B, a tuneable narrowband light
...