SIST EN IEC 62343-5-2:2018
(Main)Dynamic modules - Part 5-2: Test methods - 1xN fixed-grid WSS - Dynamic crosstalk measurement (IEC 62343-5-2:2018)
Dynamic modules - Part 5-2: Test methods - 1xN fixed-grid WSS - Dynamic crosstalk measurement (IEC 62343-5-2:2018)
This part of IEC 62343 describes the measurement methods of dynamic crosstalk during port
switching for 1 x N fixed-grid wavelength selective switches (WSSs).
The objective of this document is to establish a standard test method for different-channel
dynamic crosstalk and same-channel dynamic crosstalk that occur when a particular optical
channel signal is switched to the specific branching port against a common port in
ITU-T 50 GHz and 100 GHz fixed grid 1 x N (N ≥ 3) WSSs.
Dynamische Module - Teil 5-2: Prüfverfahren - 1×N-Festraster-WSS - Messung des dynamischen Übersprechens
Modules dynamiques - Partie 5-2: Méthodes d'essai - Commutateurs sélectifs en longueur d'onde à grille fixe 1 x N - Mesure de diaphonie dynamique
IEC 62343-5-2: 2018 décrit les méthodes de mesure de diaphonie dynamique pendant la commutation des ports pour les commutateurs sélectifs en longueur d'onde à grille fixe 1 x N. Le présent document a pour but d'établir une méthode d'essai normalisée sur la diaphonie dynamique sur différents canaux et la diaphonie dynamique sur un même canal qui se produisent lorsque le signal d'un canal optique particulier est commuté sur le port de couplage spécifique par rapport à un port commun dans des commutateurs sélectifs en longueur d'onde à grille fixe 1 x N (N ≥ 3) de 50 GHz et 100 GHz selon l'UIT-T.
Mots clés: diaphonie dynamique
Dinamični moduli - 5-2. del: Preskusne metode - 1xN WSS s fiksno mrežo - Merjenje dinamičnega presluha (IEC 62343-5-2:2018)
Ta del IEC 62343 opisuje metode merjenja dinamičnega preklopnega odmeva med preklapljanjem vrat za 1 x N stikal za izbiro valovne dolžine (WSSs) v fiksnem omrežju.
Cilj tega dokumenta je določiti standardno metodo preskušanja za dinamični preklopni odmev različnih kanalov in dinamični preklopni odmev istega kanala, do katerih pride, ko posamezni signal optičnega kanala preklopi na določena razvejilna vrata ob skupnih vratih v fiksnem omrežju ITU-T 50 GHz in 100 GHz 1 x N (N ≥ 3) WSSs.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN IEC 62343-5-2:2018
01-maj-2018
'LQDPLþQLPRGXOLGHO 3UHVNXVQHPHWRGH[1:66VILNVQRPUHåR
0HUMHQMHGLQDPLþQHJDSUHVOXKD ,(&
Dynamic modules - Part 5-2: Test methods - 1xN fixed-grid WSS - Dynamic crosstalk
measurement (IEC 62343-5-2:2018)
Ta slovenski standard je istoveten z: EN IEC 62343-5-2:2018
ICS:
33.180.01 6LVWHPL]RSWLþQLPLYODNQLQD Fibre optic systems in
VSORãQR general
SIST EN IEC 62343-5-2:2018 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN IEC 62343-5-2:2018
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SIST EN IEC 62343-5-2:2018
EUROPEAN STANDARD EN IEC 62343-5-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2018
ICS 33.180.01, 33.180.99
English Version
Dynamic modules - Part 5-2: Test methods - 1xN fixed-grid WSS
- Dynamic crosstalk measurement
(IEC 62343-5-2:2018)
Modules dynamiques - Partie 5-2: Méthodes d'essai - Dynamische Module - Teil 5-2: Prüfverfahren - 1×N-
Commutateurs sélectifs en longueur d'onde à grille fixe 1 x Festraster-WSS - Messung des dynamischen
N - Mesure de diaphonie dynamique Übersprechens
(IEC 62343-5-2:2018) (IEC 62343-5-2:2018)
This European Standard was approved by CENELEC on 2018-02-19. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62343-5-2:2018 E
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SIST EN IEC 62343-5-2:2018
EN IEC 62343-5-2:2018 (E)
European foreword
The text of document 86C/1449/CDV, future edition 1 of IEC 62343-5-2, prepared by IEC/SC 86C
"Fibre optic systems and active devices" of IEC/TC 86 "Fibre optics" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN IEC 62343-5-2:2018.
The following dates are fixed:
• latest date by which the document has to be (dop) 2018-11-19
implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2021-02-19
• latest date by which the national
standards conflicting with the
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Endorsement notice
The text of the International Standard IEC 62343-5-2:2018 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 61300-3-50 NOTE Harmonized as EN 61300-3-50.
IEC 62343-3-3:2014 NOTE Harmonized as EN 62343-3-3:2014 (not modified).
2
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SIST EN IEC 62343-5-2:2018
EN IEC 62343-5-2:2018 (E)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 61300-3-29 - Fibre optic interconnecting devices and EN 61300-3-29 -
passive components - Basic test and
measurement procedures -- Part 3-29:
Examinations and measurements -
Spectral transfer characteristics of DWDM
devices
IEC 62343 - Dynamic modules - General and guidance EN 62343 -
IEC/TR 61931 - Fibre optic - Terminology - -
IEC/TS 62538 - Categorization of optical devices - -
ISO/IEC Guide 99 - International vocabulary of metrology - - -
Basic and general concepts and
associated terms (VIM)
3
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SIST EN IEC 62343-5-2:2018
IEC 62343-5-2
®
Edition 1.0 2018-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Dynamic modules –
Part 5-2: Test methods – 1 x N fixed-grid WSS – Dynamic crosstalk measurement
Modules dynamiques –
Partie 5-2: Méthodes d'essai – Commutateurs sélectifs en longueur d'onde à grille
fixe 1 x N – Mesure de diaphonie dynamique
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.01 33.180.99 ISBN 978-2-8322-5267-3
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
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SIST EN IEC 62343-5-2:2018
– 2 – IEC 62343-5-2:2018 © IEC 2018
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 6
3.1 Basic terms . 6
3.2 Performance parameter terms . 8
3.3 Abbreviated terms . 9
4 Apparatus . 10
4.1 Test set-up . 10
4.2 Light source . 10
4.2.1 Tuneable laser source (TLS) . 10
4.2.2 Broadband light source and tuneable filter . 11
4.3 Device under test . 11
4.4 Detector . 12
4.4.1 Optical power meter (OPM) . 12
4.4.2 OE converter and oscilloscope . 12
5 Measurement condition . 13
5.1 General conditions . 13
5.2 Recommendations on selections of a branching port and channel . 13
6 Procedure . 13
6.1 Preparation . 13
6.2 Measurement . 14
6.2.1 Measurement of input power and insertion loss of DUT . 14
6.2.2 Measurement of noise power for dynamic crosstalk . 14
6.2.3 Measurement of noise power for different channel crosstalk . 14
6.2.4 Measurement of noise power for same channel crosstalk . 14
7 Example of transient characteristics of noise power . 15
8 Calculation . 17
9 Measurement report . 19
Bibliography . 21
Figure 1 – Noise observed in port during conducting port switching in 1 x N WSS . 9
Figure 2 – Test set-up to measure dynamic crosstalk . 10
Figure 3 – Transient characteristics for measurement of different channel dynamic
crosstalk . 16
Figure 4 – Transient characteristics for measurement of same channel dynamic
crosstalk . 17
Table 1 – Example of template for measurement results for different channel dynamic
crosstalk . 19
Table 2 – Example of summary of crosstalk measurement . 20
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IEC 62343-5-2:2018 © IEC 2018 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DYNAMIC MODULES –
Part 5-2: Test methods – 1 x N fixed-grid WSS –
Dynamic crosstalk measurement
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC
Publication(s)"). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62343-5-2 has been prepared by subcommittee 86C: Fibre optic
systems and active devices, of IEC technical committee 86: Fibre optics.
The text of this International Standard is based on the following documents:
CDV Report on voting
86C/1449/CDV 86C/1480/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 62343 series, published under the general title Dynamic modules,
can be found on the IEC website.
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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.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
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IEC 62343-5-2:2018 © IEC 2018 – 5 –
INTRODUCTION
Dynamic crosstalk is attributed to both channel crosstalk (due to same wavelength and/or
other wavelengths) and port isolation. It is predicted to change during port switching
operations and is a significant performance issue studied and summarized in
IEC TR 62343-6-9 for 1 x N (N ≥ 3) wavelength selective switches (WSSs).
It was revealed that dynamic crosstalk exists in actual 1 x N (N ≥ 3) WSSs in
IEC TR 62343-6-9 and predicted that it would influence transmission properties to some
extent when a specific channel passes through the WSS.
This document standardizes the measurement method of dynamic crosstalk of 1 x N (N ≥ 3)
WSSs.
This document is based on OITDA DM 01 from the Optoelectronic Industry and Technology
Development Association (OITDA).
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DYNAMIC MODULES –
Part 5-2: Test methods – 1 x N fixed-grid WSS –
Dynamic crosstalk measurement
1 Scope
This part of IEC 62343 describes the measurement methods of dynamic crosstalk during port
switching for 1 x N fixed-grid wavelength selective switches (WSSs).
The objective of this document is to establish a standard test method for different-channel
dynamic crosstalk and same-channel dynamic crosstalk that occur when a particular optical
channel signal is switched to the specific branching port against a common port in
ITU-T 50 GHz and 100 GHz fixed grid 1 x N (N ≥ 3) WSSs.
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 61300-3-29, Fibre optic interconnecting devices and passive components – Basic test
and measurement procedures – Part 3-29: Examinations and measurements – Spectral
transfer characteristics of DWDM devices
IEC TR 61931, Fibre optic – Terminology
IEC 62343, Dynamic modules – General and guidance
IEC TS 62538, Categorization of optical devices
ISO/IEC Guide 99, International vocabulary of metrology – Basic and general concepts and
associated terms (VIM)
3 Terms, definitions and abbreviated terms
For the purposes of this document, the terms and definitions given in IEC TR 61931,
IEC 62343, IEC TS 62538, ISO/IEC Guide 99, 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
3.1 Basic terms
3.1.1
fixed grid
grid where the frequency of channel spacings of WSSs having a port configuration of 1 x N
(N ≥ 2) is predetermined for all channels and not variable
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3.1.2
port pair
combination of one input port and one arbitrary output port among N ports, as for a WSS
having a port configuration of 1 x N (N ≥ 2)
Note 1 to entry: It is also valid when the WSS is used as an N x 1 port configuration. In this case, the port pair is
defined as a combination of one arbitrary input port among N ports and one output port, as for the WSS having a
port configuration of N x 1 (N ≥ 2).
3.1.3
conducting port pair
two ports, i and j, between which transfer coefficient, t , which is defined in IEC TS 62627-09,
ij
is nominally greater than zero
Note 1 to entry: The conducting port pair is defined at a specific switching state and a specified wavelength.
3.1.4
isolated port pair
two ports, i and j, between which transfer coefficient, t , which is defined in IEC TS 62627-09,
ij
is nominally zero, and logarithmic transfer coefficient, a , which is defined in IEC TS 62627-09,
ij
is nominally infinite
Note 1 to entry: The isolated port pair is defined at a specific switching state and a specified wavelength.
3.1.5
attenuating port pair
two ports, i and j, between which transfer coefficient, t , which is defined in IEC TS 62627-09,
ij
is nominally greater than zero and smaller than the insertion loss
Note 1 to entry: The attenuating port pair is defined at a specific switching state and a specified wavelength.
3.1.6
conducting channel
channel intended to be conducted at the specific conducting port pair
3.1.7
isolated channel
channel intended to be isolated at the specific conducting port pair
3.1.8
common port
port for the "1" side, not for the "N" side, with a WSS having a port configuration of 1 x N
(N ≥ 2)
3.1.9
branching port
port for the "N" side, not for the "1" side, with a WSS having a port configuration of 1 x N
(N ≥ 2)
3.1.10
static state
state when the conducting port pair, isolated port pair and attenuating port pair are not under
switching and/or attenuating operation, and the optical power is kept within 10 % in linear
scale at any intended conduction port pair
3.1.11
dynamic state
state when at least one conducting port pair, isolated port pair or attenuating port pair is
under switching and/or attenuating operation, and the optical power varies more than 10 % in
linear scale at a specific intended conduction port pair in this state
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3.2 Performance parameter terms
3.2.1
crosstalk
ratio of the transfer coefficient of the power to be isolated to the transfer coefficient for the
power to be conducted for an output port
Note 1 to entry: Crosstalk is generally a negative value expressed in dB.
Note 2 to entry: For fibre optic filters and WDM devices, crosstalk is defined for one port pair at two or more
different wavelengths (channels).
Note 3 to entry: For fibre optic switches, crosstalk is defined for two or more port pairs at one wavelength.
Note 4 to entry: Crosstalk for a passive optical device (component) is generally the maximum value of crosstalks
for all port pairs defining crosstalks.
Note 5 to entry: For WSSs, crosstalk is defined for two or more port pairs at two or more different wavelengths
(channels).
[SOURCE: IEC TS 62627-09:2016, 3.4.10, modified — Note 5 has been added.]
3.2.2
static crosstalk
crosstalk in a static state for a 1 x N (N ≥ 2) WSS, specified by the unintended signal
transmission ratio divided by the intended signal transmission ratio
Note 1 to entry: Static crosstalk is generally a negative value expressed in dB.
Note 2 to entry: Two types of static crosstalk are defined: different channel static crosstalk and same channel
static crosstalk.
3.2.3
different channel static crosstalk
static crosstalk, specified by the ratio of the isolated channel power divided by the conducting
channel power in the same conducting port pair, when the input channel power in the isolated
channel and conducting channel is the same
Note 1 to entry: Different channel static crosstalk is generally a negative value expressed in dB.
3.2.4
same channel static crosstalk
static crosstalk, specified by the ratio of the channel power in the isolated port pair divided by
the channel power in the conducting port pair, when the input channel power in the isolated
port pair and the conducting port pair are the same
Note 1 to entry: Same channel static crosstalk is generally a negative value expressed in dB.
3.2.5
dynamic crosstalk
transient crosstalk
crosstalk attributed to both channel crosstalk (due to the same wavelength and/or other
wavelengths) and port isolation, predicted to change during the switching operation in the
WSS module
Note 1 to entry: Dynamic crosstalk is generally a negative value expressed in dB.
Note 2 to entry: Two types of dynamic crosstalk are defined: different channel dynamic crosstalk and same
channel dynamic crosstalk.
Note 3 to entry: Dynamic crosstalk is applied to 1 x N (N ≥ 3) WSSs.
[SOURCE: IEC 62343-3-3:2014, 3.15, modified — The term "dynamic crosstalk" has been
added as a first preferred term, and the note to entry has been replaced by three new notes.]
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3.2.6
different channel dynamic crosstalk
optical power ratio of the isolated channel power divided by the conducting channel power in
the selected output port, when the input power of the conducting channel and the isolated
channel are the same
Note 1 to entry: Different channel dynamic crosstalk is generally a negative value expressed in dB.
Note 2 to entry: Signal leakage of the blue isolated channel in port 2 is the noise component for the red
conducting channel signal in port 2 for the demultiplexing WSSs shown in Figure 1 a).
Note 3 to entry: Different channel dynamic crosstalk is applied to 1 x N (N ≥ 3) WSSs.
3.2.7
same channel dynamic crosstalk
optical power ratio of the isolated channel power in the isolated port pair divided by the
conducting channel power in the conducting port pair, when the channel power in the input
port of the conducting port pair and the channel power in the input port of the isolated port
pair are the same
Note 1 to entry: Same channel dynamic crosstalk is applied to 1 x N (N ≥ 3) WSSs.
Note 2 to entry: Same channel dynamic crosstalk is generally a negative value expressed in dB.
Note 3 to entry: Red coloured signals in ports 1 and N are the noise components for the red signal in port 2, when
the conducting port pair for the blue signal is switched from port 1 to N in the multiplexing WSS shown in
Figure 1 b). All red signals in the isolated port pairs will be noise components. However, same channel dynamic
crosstalk is defined by the ratio of the optical loss between the conducting port pair and an isolated port pair.
Port 1
Port 1
Port 2
Port 2
Common
Port N
Common
port
port Port N
IEC
IEC
Noise observed in port during switching operation
a) Demultiplexing WSS b) Multiplexing WSS
Figure 1 – Noise observed in port during conducting port switching in 1 x N WSS
3.3 Abbreviated terms
ASE amplified spontaneous emission
DLP digital light processor
ITU-T International Telecommunication Union, Telecommunication Standardization Sector
LC liquid crystal
LCOS liquid crystal on silicon
LED light emitting diode
MEMS micro-electro-mechanical system
OE optical-to-electrical
OPM optical power meter
RBD reference branching device
TJ temporary joint
TLS tuneable laser source
WSS wavelength selective switch
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4 Apparatus
4.1 Test set-up
The test set-up consists of a light source, i.e. tuneable laser source (TLS) or broadband light
source, detector, i.e. optical power meter (OPM) or OE converter, and other equipment. An
example of the measurement set-up for measurement of the noise power to obtain the
dynamic crosstalk is given in Figure 2. The light of wavelength λ is input into the common port
of the WSS as a device under test (DUT) using TLS. Optical power, which is output from all
branching ports 1 to N, is measured simultaneously and continuously with a multi-port OPM
connected to each branching port. All apparatus are connected by the temporary joint (TJ). If
necessary, the wavelength meter with a reference branching device (RBD) may be used.
Power variation during switching of the the conducting port of the WSS is measured with the
OPM and recorded.
Figure 1 shows noise power that influences the different channel dynamic crosstalk is
generated in the case where the WSS is used as a demultiplexer, and noise power that
influences the same channel crosstalk is generated in the case where the WSS is used as a
multiplexer. However, optical noise power to measure both dynamic crosstalks is measured
with the test set-up shown in Figure 2, because the WSS is bidirectional.
In this test set-up, not only optical noise power in dynamic state but also optical noise power
in static state before and after switching the conducting port can be measured.
Port 1 to N
Common port
TJ2
Optical power meter
Wavelength: λ
Optical power meter
RBD TJ1
DUT
・・・
(WSS)
TLS
Optical power meter
Wavelength
meter
Data computation,
collection and
instrumentation
control
Electrical control and data interface
Optical connection
IEC
Figure 2 – Test set-up to measure dynamic crosstalk
4.2 Light source
4.2.1 Tuneable laser source (TLS)
The wavelength range of the TLS should be wider than the signal wavelength range of the
DUT. Optical output of the TLS should be more than 10 dB higher than the sum of the
minimum sensitivity of the optical detector, insertion loss of the test set-up [reference
branching device (RBD) and temporary joints (TJs)], insertion loss of the DUT and the
absolute value of measured dynamic crosstalk.
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SIST EN IEC 62343-5-2:2018
IEC 62343-5-2:2018 ©
...
SLOVENSKI STANDARD
oSIST prEN 62343-5-2:2017
01-september-2017
'LQDPLþQLPRGXOLGHO 3UHVNXVQHPHWRGH[1ILNVQRRPUHåMH:66
0HUMHQMHGLQDPLþQHJDSUHVOXKD
Dynamic modules - Part 5-2: Test methods - 1xN fixed-grid WSS - Dynamic crosstalk
measurement
Ta slovenski standard je istoveten z: prEN 62343-5-2:2017
ICS:
33.180.01 6LVWHPL]RSWLþQLPLYODNQLQD Fibre optic systems in
VSORãQR general
oSIST prEN 62343-5-2:2017 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN 62343-5-2:2017
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oSIST prEN 62343-5-2:2017
86C/1449/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 62343-5-2 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2017-06-02 2017-08-25
SUPERSEDES DOCUMENTS:
86C/1415/CD,86C/1446/CC
IEC SC 86C : FIBRE OPTIC SYSTEMS AND ACTIVE DEVICES
SECRETARIAT: SECRETARY:
United States of America Mr Jack Dupre
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of
which they are aware and to provide supporting documentation.
TITLE:
Dynamic modules - Part 5-2: Test methods - 1xN fixed-grid WSS - Dynamic crosstalk
measurement
NOTE FROM TC/SC OFFICERS:
Copyright © 2017 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
permission in writing from IEC.
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IEC CDV 62343-5-2 IEC:2017 – 2 – 86C/1449/CDV
1 CONTENTS
2
3 FOREWORD . 3
4 INTRODUCTION . 5
5 1 Scope . 6
6 2 Normative references . 6
7 3 Terms, definitions and abbreviations . 6
8 3.1 Basic terms and definitions . 6
9 3.2 Performance parameter definitions . 8
10 3.3 Abbreviations . 9
11 4 Apparatus . 10
12 4.1 Test set-up . 10
13 4.2 Light source . 10
14 4.2.1 Tuneable laser source (TLS). 10
15 4.2.2 Broadband light source and tuneable filter . 11
16 4.3 Device under test . 11
17 4.4 Receiver . 11
18 4.4.1 Optical power meter (OPM) . 11
19 4.4.2 OE converter and oscilloscope . 12
20 5 Measurement condition. 12
21 5.1 General condition . 12
22 5.2 Recommendations on selections of a branching port and channel . 13
23 6 Procedure . 13
24 6.1 Preparation . 13
25 6.2 Measurement . 13
26 6.2.1 Measurement of input power and insertion loss of DUT . 13
27 6.2.2 Measurement of noise power for dynamic crosstalk . 13
28 6.2.3 Measurement of noise power for different channel crosstalk . 14
29 6.2.4 Measurement of noise power for same channel crosstalk . 14
30 7 Example of transient characteristics of noise power . 14
31 8 Calculation . 16
32 9 Measurement report . 18
33 Bibliography . 20
34
35 Figure 1 – Noise observed in port during conducting port switching in 1xN WSS . 9
36 Figure 2 – Test set-up to measure dynamic crosstalk . 10
37 Figure 3 – Transient characteristics for measurement of different channel dynamic
38 crosstalk . 16
39 Figure 4 – Transient characteristics for measurement of same channel dynamic
40 crosstalk . 16
41
42 Table 1 – Example of the template of the measurement result for different channel
43 dynamic crosstalk . 18
44 Table 2 – Example of summary for crosstalk measurement . 19
45
46
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47
48 INTERNATIONAL ELECTROTECHNICAL COMMISSION
49 ____________
50
51 DYNAMIC MODULES –
52 Part 5-2: Test methods – 1xN fixed-grid WSS – Dynamic crosstalk
53 measurement
54
55
56 FOREWORD
57 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
58 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
59 international co-operation on all questions concerning standardization in the electrical and electronic fields. To
60 this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
61 Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
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63 in the subject dealt with may participate in this preparatory work. International, governmental and non-
64 governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
65 with the International Organization for Standardization (ISO) in accordance with conditions determined by
66 agreement between the two organizations.
67 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
68 consensus of opinion on the relevant subjects since each technical committee has representation from all
69 interested IEC National Committees.
70 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
71 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
72 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
73 misinterpretation by any end user.
74 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
75 transparently to the maximum extent possible in their national and regional publications. Any divergence
76 between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
77 the latter.
78 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
79 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
80 services carried out by independent certification bodies.
81 6) All users should ensure that they have the latest edition of this publication.
82 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
83 members of its technical committees and IEC National Committees for any personal injury, property damage or
84 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
85 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
86 Publications.
87 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
88 indispensable for the correct application of this publication.
89 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
90 patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
91 International Standard IEC 62343-5-2 has been prepared by subcommittee 86C: FIBRE
92 OPTIC SYSTEMS AND ACTIVE DEVICES, of IEC technical committee 86: FIBRE OPTICS.
93 The text of this International Standard is based on the following documents:
FDIS Report on voting
86C/XX/FDIS 86C/XX/RVD
94
95 Full information on the voting for the approval of this International Standard can be found in
96 the report on voting indicated in the above table.
97 This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
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98 The committee has decided that the contents of this document will remain unchanged until the
99 stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
100 the specific document. At this date, the document will be
101 • reconfirmed,
102 • withdrawn,
103 • replaced by a revised edition, or
104 • amended.
105
106 The National Committees are requested to note that for this document the stability date
107 is 2022.
108 THIS TEXT IS INCLUDED FOR THE INFORMATION OF THE NATIONAL COMMITTEES AND WILL BE
109 DELETED AT THE PUBLICATION STAGE.
110
111
112
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113 INTRODUCTION
114 Dynamic crosstalk is attributed to both channel crosstalk (due to same wavelength and/or
115 other wavelengths) and port isolation. It is predicted to change during port switching
116 operations and is a significant performance issue studied and summarized in
117 IEC TR 62343-6-9 for 1xN (N≥3) wavelength selective switch (WSS).
118 It was revealed that dynamic crosstalk exists in actual 1xN (N≥3) WSS in IEC TR 62343-6-9
119 and predicted that it would influence transmission properties to some extent when a specific
120 channel passes through the WSS.
121 This document standardizes the measurement method of dynamic crosstalk of 1xN (N≥3) WSS.
122 This standard is based on OITDA (Optoelectronic Industry and Technology Development
123 Association) Standard, OITDA DM 01, "Measurement methods of dynamic crosstalk for 1xN
124 fixed-grid wavelength selective switches".
125
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126 DYNAMIC MODULES –
127 Part 5-2: Test methods – 1xN fixed-grid WSS – Dynamic crosstalk
128 measurement
129
130 1 Scope
131 This part of the 62343 series describes the measurement methods of dynamic crosstalk
132 during port switching for 1xN fixed-grid wavelength selective switches (WSSs).
133 The objective of this part of IEC 62343 is to establish a standard test method for different-
134 channel dynamic crosstalk and same-channel dynamic crosstalk that occur when a particular
135 optical channel signal is switched to the specific branching port against a common port in
136 ITU-T 50 GHz and 100 GHz fixed grid 1xN (N≥3) WSSs.
137 2 Normative references
138 The following documents are referred to in the text in such a way that some or all of their
139 content constitutes requirements of this document. For dated references, only the edition
140 cited applies. For undated references, the latest edition of the referenced document (including
141 any amendments) applies.
142 IEC 60050, International Electrotechnical Vocabulary
143 IEC 61300-3-29, Fibre optic interconnecting devices and passive components – Basic test
144 and measurement procedures – Part 3-29: Examinations and measurements – Spectral
145 transfer characteristics of DWDM devices
146 IEC TR 61931, Fibre optic – Terminology
147 IEC 62343, Dynamic modules – General and guidance
148 IEC 62343-3-3, Dynamic modules – Part 3-3: Performance specification templates –
149 Wavelength selective switches
150 IEC TS 62538, Categorization of optical devices
151 IEC TS 62627-09 Edition 1.0 (2016-10-24), Fibre optic interconnecting devices and passive
152 components – Vocabulary for passive optical devices
153 ISO/IEC Guide 99, International vocabulary of metrology – Basic and general concepts and
154 associated terms (VIM)
155 3 Terms, definitions and abbreviations
156 For the purpose of this International Standard, the definitions of IEC 60050 (IEV),
157 IEC TR 61931, IEC 62343, IEC TS 62538, ISO/IEC Guide 99 (VIM), and the following apply.
158 ISO and IEC maintain terminological databases for use in standardization at the following
159 addresses:
160 • IEC Electropedia: available at http://www.electropedia.org/
161 • ISO Online browsing platform: available at http://www.iso.org/obp
162 3.1 Basic terms and definitions
163 3.1.1
164 fixed grid
165 frequency of channel spacings of WSS having a port configuration of 1xN (N≥2) is
166 predetermined for all channels and not variable
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167 3.1.2
168 port pair
169 combination of input port and one arbitrary output port among N ports, as for a WSS having a
170 port configuration of 1xN (N≥2)
171 NOTE 1 to entry: It is also valid when the WSS is used as Nx1 port configuration. In this case, port pair is defined
172 as a combination of one arbitrary input port among N ports and one output port, as for the WSS having a port
173 configuration of Nx1 (N≥2).
174 3.1.3
175 conducting port pair
176 two ports, i and j, between which transfer coefficient, t which is defined in IEC TS 62627-09
ij
177 is nominally greater than zero
178 Note 1 to entry: Conducting port pair is defined at a specific switching state and a specified wavelength.
179 [SOURCE: IEC TS 62627-09, 3.2.8, modified]
180 3.1.4
181 isolated port pair
182 two ports, i and j, between which transfer coefficient, t which is defined in IEC TS 62627-09
ij
183 is nominally zero, and logarithmic transfer coefficient, a which is defined in IEC TS 62627-09
ij
184 is nominally infinite
185 Note 1 to entry: Isolated port pair is defined at a specific switching state and a specified wavelength.
186 [SOURCE: IEC TS 62627-09, 3.2.9, modified]
187 3.1.5
188 attenuating port pair
189 two ports, i and j, between which transfer coefficient, t which is defined in IEC TS 62627-09
ij
190 is nominally greater than zero and smaller than insertion loss
191 Note 1 to entry: Attenuating port pair is defined at a specific switching state and a specified wavelength.
192 3.1.6
193 conducting channel
194 channel intended to be conducted at the specific conducting port pair
195 3.1.7
196 isolated channel
197 channel intended to be isolated at the specific conducting port pair
198 3.1.8
199 common port
200 port for “1” side, not for “N” side, with WSS having a port configuration of 1xN (N≥2)
201 3.1.9
202 branching port
203 port for “N” side, not for “1” side, with WSS having a port configuration of 1xN (N≥2)
204 3.1.10
205 static state
206 state when conducting port pair, isolated port pair and attenuating port pair are not under
207 switching and/or attenuating operation, and the optical power is kept within 10 % in linear
208 scale at any intended conduction port pair
209 3.1.11
210 dynamic state
211 state when at least one conducting port pair, isolated port pair or attenuating port pair is
212 under switching and/or attenuating operation, and optical power varies more than 10 % in
213 linear scale at a specific intended conduction port pair in this state
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214 3.2 Performance parameter definitions
215 3.2.1
216 crosstalk
217 ratio of the transfer coefficient of the power to be isolated to the transfer coefficient for the
218 power to be conducted for an output port
219 Note 1 to entry: Crosstalk is generally a negative value expressed in dB.
220 Note 2 to entry: For fibre optic filters and WDM devices, crosstalk is defined for one port pair at two or more
221 different wavelengths (channels).
222 Note 3 to entry: For fibre optic switches, crosstalk is defined for two or more port pairs at one wavelength.
223 Note 4 to entry: Crosstalk for a passive optical device (component) is generally the maximum value of crosstalks
224 for all port pairs defining crosstalks.
225 Note 5 to entry: For WSS, crosstalk is defined for two or more port pairs at two or more different wavelengths
226 (channels).
227 [SOURCE: IEC TS 62627-09, 3.4.10, modified]
228 3.2.2
229 static crosstalk
230 crosstalk in a static state for 1xN (N≥2) WSS. Static crosstalk is the ratio of unintended signal
231 transmission ratio divided by intended signal transmission ratio
232 Note 1 to entry: Static crosstalk is generally a negative value expressed in dB.
233 Note 2 to entry: Two types of static crosstalk are defined: different channel static crosstalk and same channel
234 static crosstalk.
235 3.2.3
236 different channel static crosstalk
237 static crosstalk, specified by ratio of isolated channel power divided by conducting channel
238 power in the same conducting port pair, when the input channel power in the isolated channel
239 and conducting channel is the same
240 Note 1 to entry: Different channel static crosstalk is generally a negative value expressed in dB.
241 3.2.4
242 same channel static crosstalk
243 static crosstalk, specified by ratio of channel power in the isolated port pair divided by the
244 channel power in the conducting port pair, when the input channel power in the isolated port
245 pair and the conducting port pair are the same
246 Note 1 to entry: Same channel static crosstalk is generally a negative value expressed in dB.
247 3.2.5
248 dynamic crosstalk
249 transient crosstalk
250 crosstalk attributed to both channel crosstalk (due to same wavelength and/or other
251 wavelengths) and port isolation, predicted to change during switching operation in WSS
252 module
253 Note 1 to entry: Dynamic crosstalk is generally a negative value expressed in dB.
254 Note 2 to entry: Two types of dynamic crosstalk are defined: different channel dynamic crosstalk and same
255 channel dynamic crosstalk.
256 Note 3 to entry: Dynamic crosstalk is applied to 1xN (N≥3) WSSs.
257 [SOURCE: IEC 62343-3-3, modified]
258 3.2.6
259 different channel dynamic crosstalk
260 optical power ratio of isolated channel power divided by conducting channel power in the
261 selected output port, when the input power of the conducting channel and the isolated
262 channel are the same
263 Note 1 to entry: Different channel dynamic crosstalk is generally a negative value expressed in dB.
264 Note 2 to entry: Signal leakage of the blue isolated channel in port 2 is the noise component for the red conducting
265 channel signal in port 2 for the demultiplexing WSSs shown in Figure 1(a).
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266 Note 3 to entry: Different channel dynamic crosstalk is applied to 1xN (N≥3) WSSs.
267 3.2.7
268 same channel dynamic crosstalk
269 optical power ratio of isolated channel power in the isolated port pair divided by conducting
270 channel power in the conducting port pair, when the channel power in the input port of the
271 conducting port pair and the channel power in the input port of the isolated port pair are the
272 same. Same channel dynamic crosstalk is applied to 1xN (N≥3) WSSs
273 Note 1 to entry: Same channel dynamic crosstalk is generally a negative value expressed in dB.
274 Note 2 to entry: Red coloured signals in ports 1 and N are the noise components for the red signal in port 2, when
275 the conducting port pair for the blue signal is switched from port 1 to N in the multiplexing WSS shown in Figure
276 1(b). All red signals in the isolated port pairs will be noise components. However, same channel dynamic crosstalk
277 is defined by the ratio of the optical loss between the conducting port pair and an isolated port pair.
278
Port 1 Port 1
279
Port 2
Port 2
280
281
Common
Common
Port N
Port N
282
port
port
283
284
Noise observed in port during switching operation
285
286 (a) Demultiplexing WSS (b) Multiplexing WSS
287 Figure 1 – Noise observed in port during conducting port switching in 1xN WSS
288 3.3 Abbreviations
289 ASE amplified spontaneous emission
290 DEMUX demultiplexing
291 DWDM dense wavelength division multiplexing
292 ITU-T International Telecommunication Union, Telecommunication
293 Standardization Sector
294 LC liquid crystal
295 LCOS liquid crystal on silicon
296 LED light emitting diode
297 MEMS micro-electro-mechanical system
298 MUX multiplexing
299 OE optical-to-electrical
300 OPM optical power meter
301 PDL polarization dependent loss
302 RBD reference branching device
303 ROADM reconfigurable optical add drop multiplexing
304 TJ temporary joint
305 TLS tuneable laser source
306 WSS wavelength selective switch
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307 4 Apparatus
308 4.1 Test set-up
309 The test set up consists of a light source, i.e. tuneable laser source (TLS) or broadband light
310 source, receiver, i.e. optical power meter (OPM) or OE converter, and other equipment. An
311 example of the measurement set-up for measurement of the noise power to obtain the
312 dynamic crosstalk is given in Figure 2. The light of wavelength λ is input into the common port
313 of the WSS as a device under test (DUT) using TLS. Optical power, which is output from all
314 branching ports 1 to N, is measured simultaneously and continuously with a multi-port OPM
315 connected to each branching port. All apparatus are connected by the temporary joint (TJ). If
316 necessary, the wavelength meter with a reference branching device (RBD) may be used.
317 Power variation during switching the conducting port of the WSS is measured with the OPM
318 and recorded.
319 Figure 1 shows noise power that influences the different channel dynamic crosstalk is
320 generated in the case when the WSS is used as a demultiplexer, and noise power that
321 influences the same channel crosstalk is generated in the case when WSS is used as
322 multiplexer. However, optical noise power to measure both dynamic crosstalks is measured
323 with the test set up shown in Figure 2, because WSS is bidirectional.
324 In this test set up, not only optical noise power in dynamic state but also optical noise power
325 in static state before and after switching the conducting port can be measured.
326
Port 1 to N
Common port
TJ2
Optical power meter
Wavelength: λ
Optical power meter
RBD TJ1
・・・
DUT
TLS (WSS)
Optical power meter
Wavelength
meter
Data computation,
collection and
instrumentation
control
Electrical control and data interface
Optical connection
327
328 Figure 2 – Test set-up to measure dynamic crosstalk
329 4.2 Light source
330 4.2.1 Tuneable laser source (TLS)
331 The wavelength range of the TLS should be wider than the signal wavelength range of the
332 DUT. Optical output of the TLS should be more than 10 dB higher than the sum of the
333 minimum sensitivity of the optical receiver, insertion loss of test set up [reference branching
334 device (RBD) and temporary joints (TJs)], insertion loss of the DUT and the absolute value of
335 measured dynamic crosstalk.
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336 The side mode suppression ratio and signal to total source spontaneous emission ratio of the
337 TLS should be more than 10 dB higher than the absolute value of measured dynamic
338 crosstalk. For example, when the expected minimum value of dynamic crosstalk on the DUT is
339 -40 dB, the signal to total source spontaneous emission of the TLS should be more than
340 50 dB. When the TLS does not have enough signal to total source spontaneous emission ratio,
341 an appropriate tracking filter should be placed behind the TLS.
342 In the case of an ITU-T 50 GHz fixed grid and an ITU-T 100 GHz fixed grid, wavelength
343 accuracy of the TLS should be within ±10 pm and ±20 pm, respectively. When wavelength
344 accuracy is insufficient, output wavelength should be monitored by a wavelength meter and
345 calibrated when necessary.
346 The spectral width of the TLS should be narrow enough for the pass band of the WSS. Less
347 than 10 % of pass band is desirable.
348 In order to remove the influence of polarization dependent loss of the WSS, a polarization
349 scrambler shall be placed after the TLS. The polarization scrambler shall have a speed fast
350 enough (more than 10 times is desirable) than averaging time of the receiver.
351 4.2.2 Broadband light source and tuneable filter
352 A substitute system for the TLS is a test set up that combines a broadband light source and
353 tuneable filter.
354 The broadband light source should be an LED or light source that is depolarized and has a
355 wide ASE spectrum. The spectrum of the light source should be wider than the signal
356 wavelength range of the DUT.
357 A tuneable filter is used to set the wavelength to be measured. The wavelength range of the
358 tuneable filter should be wider than the operating wavelength range of the DUT.
359 The accuracy of the centre wavelength of the tuneable filter should be within ±10 pm. The
360 tuneable filter has pass band that is narrow enough compared to that of the WSS (less than
361 10 % of the pass band is desirable) and wavelength isolation of more than 50 dB between the
362 pass band and the stop band.
363 The optical output power generated by combining the broadband light source and tuneable
364 filter should be more than 10 dB higher than the sum of the minimum sensitivity of the optical
365 receiver, insertion loss of test set up (RBD and TJs), insertion loss of the DUT and absolute
366 value of measured dynamic crosstalk.
367 4.3 Device under test
368 The driving engine of the WSS is one of the following:
369 • one dimensional arrayed MEMS mirror that uses MEMS technology
370 • two dimensional arrayed MEMS mirrors that uses digital light processor (DLP)
371 • one dimensional arrayed LC element that uses LC technology,
372 • two dimensional arrayed LCOS element
373 • hybrid technology combining MEMS and LC.
374 There are two types of WSS
...
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