IEC 62333-2:2006

Noise suppression sheet for digital devices and equipment - Part 2: Measuring methods

IEC 62333-2:2006 specifies the methods for measuring the electromagnetic characteristics of a noise suppression sheet. Those methods are intended to provide useful and repeatable measurements to characterize the performance of the noise suppression sheets, so that manufacturers and their customers are able to obtain the same results.
This publication is to be read in conjunction with IEC 62333-1:2006.

Plaque réduisant le bruit des dispositifs et appareils numériques - Partie 2: Méthodes de mesure

La CEI 62333-2:2006 spécifie les méthodes de mesure des caractéristiques électromagnétiques d'une plaque réduisant le bruit. Ces méthodes sont destinées à fournir des mesures utiles et reproductibles pour caractériser les performances des plaques réduisant le bruit, de sorte que les fabricants et leurs clients puissent obtenir les mêmes résultats.
Cette publication doit être lue conjointement avec la CEI 62333-1:2006.

General Information

• Status: Published
• Publication Date: 04-Aug-2015
• ICS: 29.100.10 - Magnetic components
• Technical Committee: TC 51 - Magnetic components, ferrite and magnetic powder materials
• Drafting Committee: WG 10 - TC 51/WG 10
• Current Stage: PPUB - Publication issued
• Start Date: 23-May-2006
• Completion Date: 15-Aug-2006

Relations

• Amended By: IEC 62333-2:2006/AMD1:2015 - Amendment 1 - Noise suppression sheet for digital devices and equipment - Part 2: Measuring methods
• Effective Date: 05-Sep-2023

Overview

IEC 62333-2:2006, published by the International Electrotechnical Commission (IEC), defines standardized measuring methods for evaluating the electromagnetic characteristics of noise suppression sheets (NSS) used in digital devices and equipment. By following the procedures set out in this standard, manufacturers and end-users can reliably characterize and compare the performance of different noise suppression solutions. IEC 62333-2 is intended to ensure consistency and repeatability in test results, helping to minimize electromagnetic interference (EMI) in electronic systems. This document should be read in conjunction with IEC 62333-1:2006, which covers definitions and general properties of NSS.

Key Topics

IEC 62333-2:2006 covers several essential aspects of noise suppression sheet performance verification:

• Measurement Principles: The standard describes test setups and evaluation methods to quantify how well a noise suppression sheet reduces electromagnetic noise.
• Parameter Evaluation: It defines four main electrical parameters for assessing NSS effectiveness:
  • Intra-decoupling ratio (Rda): Reduction of coupling between circuits on the same side of the NSS.
  • Inter-decoupling ratio (Rde): Reduction of coupling between circuits on opposite sides of the NSS.
  • Transmission attenuation power ratio (Rtp): Decrease in noise along transmission lines, such as microstrip lines, caused by NSS installation.
  • Radiation suppression ratio (Rrs): Decrease in electromagnetic radiation from a source after applying the NSS.
• Measuring Apparatus and Configuration: Includes recommendations for loop antenna types, network analyzers, microstrip line (MSL) test fixtures, and the physical arrangement of test samples.

Applications

IEC 62333-2 is valuable for a variety of practical applications in the electronics industry:

• Product Development and Quality Control: Manufacturers of electronic devices and NSS materials use IEC 62333-2 to validate product performance and to ensure compliance with EMI regulations.
• Comparative Testing: The repeatable protocols enable objective comparison between different types or brands of noise suppression sheets, aiding purchasing and design decisions.
• EMI Suppression in Digital Equipment: The standard supports the reduction of unwanted electromagnetic emissions in digital products, improving signal integrity and device reliability.
• Component Specification and Procurement: Both component suppliers and OEMs rely on standardized measurements to specify NSS properties in datasheets and procurement documents.
• Regulatory Compliance: Adhering to IEC 62333-2 supports alignment with international EMI standards and may facilitate global market access.

Related Standards

For comprehensive noise suppression solutions and accurate electromagnetic interference assessment, consider the following related IEC standards:

• IEC 62333-1:2006 – Noise suppression sheets for digital devices and equipment – Part 1: Definitions and general properties
• CISPR 16-1 – Specification for radio disturbance and immunity measuring apparatus and methods – Part 1: Radio disturbance and immunity measuring apparatus
• CISPR 22 – Information technology equipment – Radio disturbance characteristics – Limits and methods of measurement

Practical Value

Applying IEC 62333-2:2006 improves the transparency and reliability of electromagnetic performance claims for noise suppression sheets. This, in turn, helps designers and engineers build digital devices with robust EMI control, leading to higher product quality and compliance with regulatory standards in global markets. With consistent measurement techniques, organizations can make informed decisions during product development, procurement, and system integration, ultimately reducing interference issues and enhancing device performance.

Keywords: IEC 62333-2, noise suppression sheet, electromagnetic interference, EMI, measuring methods, digital equipment, transmission attenuation, decoupling ratio, standards compliance, CISPR

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 62333-2
First edition
2006-05
Noise suppression sheet for digital
devices and equipment –
Part 2:
Measuring methods
Reference number
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.
Consolidated editions
The IEC is now publishing consolidated versions of its publications. For example,
edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
base publication incorporating amendment 1 and the base publication incorporating
amendments 1 and 2.
Further information on IEC publications
The technical content of IEC publications is kept under constant review by the IEC,
thus ensuring that the content reflects current technology. Information relating to
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Information on the subjects under consideration and work in progress undertaken
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INTERNATIONAL IEC
STANDARD 62333-2
First edition
2006-05
Noise suppression sheet for digital
devices and equipment –
Part 2:
Measuring methods
 IEC 2006  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale S
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 62333-2  IEC:2006(E)
CONTENTS
FOREWORD.3

1 Scope.5
2 Normative references.5
3 General.5
4 Measuring methods
4.1 Intra-decoupling ratio: R .6
da
4.2 Inter-decoupling ratio: R .11
de
4.3 Transmission attenuation power ratio: R .15
tp
4.4 Radiation suppression ratio: R .18
rs
Figure 1 – Schematic diagram of a pair of antennas and NSS under test .6
Figure 2 – A pair of antennas and NSS under test .6
Figure 3 – Frequency response of coupling between a pair of antennas.7
Figure 4 – Recommended examples of small loop antennas for the measurement .8
Figure 5 – Cross sectional view of the measuring configuration .9
Figure 6 – Schematic diagram of the measuring configuration .10
Figure 7 – Schematic diagram of a pair of loop antennas and test sample .12
Figure 8 – Schematic diagram of a pair of antenna and test sample.12
Figure 9 – Schematic diagram of the measuring configuration .13
Figure 10 – Schematic diagram of the measuring method for transmission attenuation
power ratio R .15
tp
Figure 11 – Data examples of the measurement results .18
Figure 12 – Measurement system diagram of R .19
rs
Figure 13 – Schematic diagram of test fixture .19
Figure 14 – Size and structure of test fixture.20
Figure 15 – Test sample attachment on test fixture .22
Figure 16 – Test fixture setup on turntable.22

Table 1 – Merits and limitations of the recommended antennas .9
Table 2 – Dimensions of loop antennas .9
Table 3 – Dimensions of test sample .10
Table 4 – Dimensions of loop antennas .13
Table 5 – Dimensions of test fixture .16
Table 6 – Dimensions of test sample .16
Table 7 – Dimensions of test fixture .20
Table 8 – Dimensions of test sample .21

62333-2  IEC:2006(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
NOISE SUPPRESSION SHEET
FOR DIGITAL DEVICES AND EQUIPMENT –

Part 2: Measuring methods
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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 62333-2 has been prepared IEC technical committee 51: Magnetic
components and ferrite materials.
This standard is to be used in conjunction with IEC 62333-1.
The text of this standard is based on the following documents:
FDIS Report on voting
51/853/FDIS 51/861/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.

– 4 – 62333-2  IEC:2006(E)
IEC 62333 consists of the following parts, under the general title Noise suppression sheet for
digital devices and equipment:
Part 1: Definitions and general properties
Part 2: Measuring methods
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 publication may be issued at a later date.

62333-2  IEC:2006(E) – 5 –
NOISE SUPPRESSION SHEET
FOR DIGITAL DEVICES AND EQUIPMENT –

Part 2: Measuring methods
1 Scope
This part of IEC 62333 specifies the methods for measuring the electromagnetic
characteristics of a noise suppression sheet. Those methods are intended to provide useful
and repeatable measurements to characterize the performance of the noise suppression
sheets, so that manufacturers and their customers are able to obtain the same results.
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 amendment) applies.
IEC 62333-1, Noise suppression sheet for digital devices and equipment – Part 1: Definitions
and general properties
CISPR 16-1, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1: Radio disturbance and immunity measuring apparatus
CISPR 22, Information technology equipment – Radio disturbance characteristics – Limits and
methods of measurement
3 General
Electromagnetic interference between electronic devices, and emission of radiation from
electronic devices are caused, in part, by RF current generated by active devices which are
driven at high frequency. Printed-circuit board (PCB), devices mounted on the PCB, and all
other connected circuits or cables can act as antennas to radiate the RF noise. Levels of the
electromagnetic interference and the emission are proportional to the RF current, and are also
affected significantly by PCB design, radiation efficiency of the antennas, and noise coupling
coefficients between the devices and the antennas.
The noise suppression sheet (NSS) is used for decoupling of the noise path, suppressing RF
noise current, and reducing radiation. The noise suppression effect of the NSS can be
evaluated by four parameters. They are defined as intra-decoupling ratio (R ), inter-
da
decoupling ratio (R ), transmission attenuation power ratio (R ) and radiation suppression
de tp
ratio (R ).
rs
A pair of antennas is held close to each other for the measuring intra-decoupling ratio (R )
da
and inter-decoupling ratio (R ). One antenna acts as a noise source and another one as a
de
receiver. Both decoupling ratios are derived from comparison before and after the NSS is
installed nearby the antennas. These measuring procedures represent practical configurations
of the NSS. Practically, the NSS is installed near the noise source or the noise interfered part,
inside of the electronic equipments.

– 6 – 62333-2  IEC:2006(E)
A micro-strip line (MSL) test fixture is used for the measuring transmission attenuation power
ratio (R ) as a transmission line that would be a noise path. The ratio is derived from
tp
comparison before and after the NSS installation. This measuring procedure represents
another practical configuration that the NSS is utilized for reducing the RF current along the
transmission line.
The MSL test fixture is also used for measuring radiation suppression ratio (R ) as the
rs
antenna. The ratio is derived from a comparison before and after the NSS installation. This
measuring procedure represents another practical configuration that the NSS is utilized for
reducing the radiation from the antenna.
4 Measuring methods
4.1 Intra-decoupling ratio: R
da
4.1.1 Principle
The following measuring method is applied for evaluating a reduction of coupling between
lines or circuit boards on one side of the NSS, from 100 MHz to 6 GHz.
A pair of loop antennas is employed. One is for noise source and the other one for receiver.
They are simulating a general electromagnetic interference situation that often exists inside
electronic equipment (see Figure 1).
The NSS is placed so that the centre of the antenna pair comes to the centre of the NSS. The
coupling between two antennas with the NSS is measured, as well as the coupling without the
NSS as a reference value. Consequently, intra-decoupling ratio R (dB) can be obtained.
da
RF magnetic field raised by one antenna is coupled with another one (see Figure 2a). By
setting the NSS, the antennas (see Figure 2b), a part of the magnetic flux is led to the NSS,
and the coupling is reduced by electromagnetic loss in the material.

Loop antennas
Network
NSS
analyzer
Magnetic flux
Coaxial cable
IEC  637/06
Figure 1 – Schematic diagram of a pair of antennas and NSS under test

62333-2  IEC:2006(E) – 7 –
Magnetic flux
NSS
IEC  638/06 IEC  639/06
Figure 2a – Loop antennas
Figure 2b – NSS under test
Figure 2 – A pair of antennas and NSS under test
4.1.2 Apparatus
Figure 1 shows the schematic diagram of the measuring method of intra-decoupling ratio.
NOTE The test sample and the loop antennas are set at least 30 mm away from any other material except for the
coaxial cable, using low dielectric and low loss material such as the styrene foam and air gap.
Small loop antennas shall be used for the generation of the RF magnetic field and the
detection of the magnetic flux.
The S of the ideal loop antenna pair is proportional to the frequency. This means that S
21 21
increases 20 dB with the decade of frequency. The usable frequency range of the loop
antenna is defined by the deviation of S from the theoretical value. The deviation should be
less than ±3 dB as shown in Figure 3.

Theoretical
20 dB/decade
20 dB
+3 dB
20 dB
–3 dB
f 10f
f/10
Frequency
IEC  640/06
Figure 3 – Frequency response of coupling between a pair of antennas
Several loop antenna designs shown in Figure 4 are capable of achieving the 20 dB/decade
frequency response that defines a valid R /R measurement.
da de
4.1.2.1 Loop antenna
Recommended examples of the small antennas are shown in Figure 4. Merits and limitations
of recommended examples of the antennas are described in Table 1.

Coupling S
– 8 – 62333-2  IEC:2006(E)
Slit ≤ φ /10
a
Slit
•
Loop antenna
st rd
1 /3
Via hole
layer
Soldering
Substrate
Semi-rigid cable
nd
layer
50 Ω termination
Connector
Connector
IEC  641/06 IEC  642/06
Figure 4b – Shielded loop antenna
Figure 4a – Shielded multi-layered
with slit and 50 Ω termination
antenna with slit
Slit ≤ φ /10
a
•
Ferrite
beads
Connector
Connector
IEC  643/06 IEC  644/06
Figure 4c – One turn antenna Figure 4d – Shielded coaxial
antenna with slit
with ferrite beads
Connector
Semi-rigid cable
Slit
Electrical shorting plate
50 Ω termination
IEC  645/06
Figure 4e – Shield loop antenna
with electrical shorting plate

Figure 4 – Recommended examples of small loop antennas for the measurement
...

IEC 62333-2 ®
Edition 1.0 2006-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Noise suppression sheet for digital devices and equipment –
Part 2: Measuring methods
Plaque réduisant le bruit des dispositifs et appareils numériques –
Partie 2: Méthodes de mesure
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IEC 62333-2 ®
Edition 1.0 2006-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Noise suppression sheet for digital devices and equipment –
Part 2: Measuring methods
Plaque réduisant le bruit des dispositifs et appareils numériques –
Partie 2: Méthodes de mesure
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX S
ICS 29.100.10 ISBN 978-2-88912-593-7

– 2 – 62333-2  IEC:2006
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 General . 5
4 Measuring methods . 6
4.1 Intra-decoupling ratio: R . 6
da
4.2 Inter-decoupling ratio: R . 11
de
4.3 Transmission attenuation power ratio: R . 14
tp
4.4 Radiation suppression ratio: R . 18
rs
Figure 1 – Schematic diagram of a pair of antennas and NSS under test . 6
Figure 2 – A pair of antennas and NSS under test . 7
Figure 3 – Frequency response of coupling between a pair of antennas . 7
Figure 4 – Recommended examples of small loop antennas for the measurement . 8
Figure 5 – Cross-sectional view of the measuring configuration . 9
Figure 6 – Schematic diagram of the measuring configuration . 10
Figure 7 – Schematic diagram of a pair of loop antennas and test sample . 12
Figure 8 – Schematic diagram of a pair of antenna and test sample . 12
Figure 9 – Schematic diagram of the measuring configuration . 13
Figure 10 – Schematic diagram of the measuring method for transmission attenuation
power ratio R . 15
tp
Figure 11 – Data examples of the measurement results . 17
Figure 12 – Measurement system diagram of R . 18
rs
Figure 13 – Schematic diagram of test fixture . 18
Figure 14 – Size and structure of test fixture . 19
Figure 15 – Test sample attachment on test fixture . 21
Figure 16 – Test fixture set-up on turntable . 21

Table 1 – Merits and limitations of the recommended antennas . 9
Table 2 – Dimensions of loop antennas . 9
Table 3 – Dimensions of test sample . 10
Table 4 – Dimensions of loop antennas . 13
Table 5 – Dimensions of test fixture . 15
Table 6 – Dimensions of test sample . 16
Table 7 – Dimensions of test fixture . 19
Table 8 – Dimensions of test sample . 20

62333-2  IEC:2006 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
NOISE SUPPRESSION SHEET
FOR DIGITAL DEVICES AND EQUIPMENT –

Part 2: Measuring methods
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 62333-2 has been prepared IEC technical committee 51: Magnetic
components and ferrite materials.
This standard is to be used in conjunction with IEC 62333-1.
This bilingual version (2011-07) replaces the English version.
The text of this standard is based on the following documents:
FDIS Report on voting
51/853/FDIS 51/861/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.

– 4 – 62333-2  IEC:2006
The French version of this standard has not been voted upon.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
IEC 62333 consists of the following parts, under the general title Noise suppression sheet for
digital devices and equipment:
Part 1: Definitions and general properties
Part 2: Measuring methods
The committee has decided that the contents of this publication will remain unchanged until
the stability 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.
62333-2  IEC:2006 – 5 –
NOISE SUPPRESSION SHEET
FOR DIGITAL DEVICES AND EQUIPMENT –

Part 2: Measuring methods
1 Scope
This part of IEC 62333 specifies the methods for measuring the electromagnetic
characteristics of a noise suppression sheet. Those methods are intended to provide useful
and repeatable measurements to characterize the performance of the noise suppression
sheets, so that manufacturers and their customers are able to obtain the same results.
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 amendment) applies.
IEC 62333-1, Noise suppression sheet for digital devices and equipment – Part 1: Definitions
and general properties
CISPR 16-1, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1: Radio disturbance and immunity measuring apparatus
CISPR 22, Information technology equipment – Radio disturbance characteristics – Limits and
methods of measurement
3 General
Electromagnetic interference between electronic devices, and emission of radiation from
electronic devices are caused, in part, by RF current generated by active devices which are
driven at high frequency. Printed-circuit board (PCB), devices mounted on the PCB, and all
other connected circuits or cables can act as antennas to radiate the RF noise. Levels of the
electromagnetic interference and the emission are proportional to the RF current, and are also
affected significantly by PCB design, radiation efficiency of the antennas, and noise coupling
coefficients between the devices and the antennas.
The noise suppression sheet (NSS) is used for decoupling of the noise path, suppressing RF
noise current, and reducing radiation. The noise suppression effect of the NSS can be
evaluated by four parameters. They are defined as intra-decoupling ratio (R ), inter-
da
decoupling ratio (R ), transmission attenuation power ratio (R ) and radiation suppression
de tp
ratio (R ).
rs
A pair of antennas is held close to each other for the measuring intra-decoupling ratio (R )
da
and inter-decoupling ratio (R ). One antenna acts as a noise source and another one as a
de
receiver. Both decoupling ratios are derived from comparison before and after the NSS is
installed nearby the antennas. These measuring procedures represent practical configurations
of the NSS. Practically, the NSS is installed near the noise source or the noise interfered part,
inside of the electronic equipments.

– 6 – 62333-2  IEC:2006
A micro-strip line (MSL) test fixture is used for the measuring transmission attenuation power
ratio (R ) as a transmission line that would be a noise path. The ratio is derived from
tp
comparison before and after the NSS installation. This measuring procedure represents
another practical configuration that the NSS is utilized for reducing the RF current along the
transmission line.
The MSL test fixture is also used for measuring radiation suppression ratio (R ) as the
rs
antenna. The ratio is derived from a comparison before and after the NSS installation. This
measuring procedure represents another practical configuration that the NSS is utilized for
reducing the radiation from the antenna.
4 Measuring methods
4.1 Intra-decoupling ratio: R
da
4.1.1 Principle
The following measuring method is applied for evaluating a reduction of coupling between
lines or circuit boards on one side of the NSS, from 100 MHz to 6 GHz.
A pair of loop antennas is employed. One is for noise source and the other one for receiver.
They are simulating a general electromagnetic interference situation that often exists inside
electronic equipment (see Figure 1).
The NSS is placed so that the centre of the antenna pair comes to the centre of the NSS. The
coupling between two antennas with the NSS is measured, as well as the coupling without the
(dB) can be obtained.
NSS as a reference value. Consequently, intra-decoupling ratio R
da
RF magnetic field raised by one antenna is coupled with another one (see Figure 2a). By
setting the NSS, the antennas (see Figure 2b), a part of the magnetic flux is led to the NSS,
and the coupling is reduced by electromagnetic loss in the material.

Loop antennas
Network
NSS
analyzer
Magnetic flux
Coaxial cable
IEC  637/06
Figure 1 – Schematic diagram of a pair of antennas and NSS under test

62333-2  IEC:2006 – 7 –
Magnetic flux
NSS
IEC  638/06 IEC  639/06
Figure 2a – Loop antennas Figure 2b – NSS under test

Figure 2 – A pair of antennas and NSS under test
4.1.2 Apparatus
Figure 1 shows the schematic diagram of the measuring method of intra-decoupling ratio.
NOTE The test sample and the loop antennas are set at least 30 mm away from any other material except for the
coaxial cable, using low dielectric and low loss material such as the styrene foam and air gap.
Small loop antennas shall be used for the generation of the RF magnetic field and the
detection of the magnetic flux.
The S of the ideal loop antenna pair is proportional to the frequency. This means that S
21 21
increases 20 dB with the decade of frequency. The usable frequency range of the loop
antenna is defined by the deviation of S from the theoretical value. The deviation should be
less than ±3 dB as shown in Figure 3.

Theoretical
20 dB/decade
20 dB
+3 dB
20 dB
–3 dB
f 10f
f/10
Frequency
IEC  640/06
Figure 3 – Frequency response of coupling between a pair of antennas
Several loop antenna designs shown in Figure 4 are capable of achieving the 20 dB/decade
frequency response that defines a valid R /R measurement.
da de
4.1.2.1 Loop antenna
Recommended examples of the small antennas are shown in Figure 4. Merits and limitations
of recommended examples of the antennas are described in Table 1.

Coupling S
– 8 – 62333-2  IEC:2006
Slit ≤ φ /10
a
Slit
•
Loop antenna
st rd
1 /3
Via hole
layer
Soldering
Substrate
Semi-rigid cable
nd
layer
50 Ω termination
Connector
Connector
IEC  641/06
IEC  642/06
Figure 4b – Shielded loop antenna
Figure 4a – Shielded multi-layered
with slit and 50 Ω termination
antenna with slit
Slit ≤ φ /10
a
•
Ferrite
beads
Connector
Connector
IEC  643/06 IEC  644/06
Figure 4c – One turn antenna Figure 4d – Shielded coaxial
antenna with slit
with ferrite beads
Connector
Semi-rigid cable
Slit
Electrical shorting plate
50 Ω termination
IEC  645/06
Figure 4e – Shield loop antenna
with electrical shorting plate

Figure 4 – Recommended examples of small loop antennas for the measurement

62333-2  IEC:2006 – 9 –
Table 1 – Merits and limitations of the recommended antennas
Frequency range
Loop antenna type (approx.) Fabrication Materials
GHz
Shielded multi-layer antenna PCB manufacturing PCB material
a) 0,1 to 3
with slit process required Ex. FR-4
Shielded loop antenna with Engineering skills Semi-rigid cable
b) 0,1 to 6
required
50 Ω termination
One turn antenna with ferrite Easy Semi-rigid cable
c) beads 0,1 to 2 Ferrite beads
Ex. NiCuZn ferrite
Shielded coaxial antenna with Easy Semi-rigid cable
d) 0,1 to 2
slit
Shield loop antenna with Easy Semi-rigid cable
e) 0,1 to 6
electrical shorting plate
Slit width shown in Figures 4a), b), d) and e) shall be less than φ /10, where φ is average
a a
diameter of the loop antenna.
A pair of loop antennas shall be arranged as shown in Figure 5. The dimensions of loop
antennas are specified as shown in Table 2.

Test sample
D
θ θ
φ
a
Loop antennas
IEC  646/06
D is the distance between centres of the loop antennas;
φ is the average diameter of the loop antenna;
a
H is the clearance between test sample and the antenna surface;
θ is the angle between test sample and each loop antenna surface.
Figure 5 – Cross-sectional view of the measuring configuration
Table 2 – Dimensions of loop antennas
Distance D Clearance H Angle θ
Diameter φ
a
mm mm mm radian
a
6,0 ± 0,2 3,0 ± 0,2 3,0 ± 0,2 ≤ π/18
a
≤ 10 degrees
H
– 10 – 62333-2  IEC:2006
4.1.2.2 Network analyzer
A network analyzer should be prepared both for signal source and signal receiver. A
calibration of the network analyzer should be done at the nearest point of loop antenna. The
combination of a signal generator and a receiver will be used as an alternative measuring
equipment.
4.1.3 Test sample
The dimensions of test samples are specified in Figure 6 and Table 3.

Loop antenna
Slit
Slit
W
Test sample
L
IEC  647/06
L is the length of test sample;
W is the width of test sample.
Figure 6 – Schematic diagram of the measuring configuration
Table 3 – Dimensions of test sample
Length L Width W
mm mm
≥ 40 ≥ 40
NOTE Any thickness of the test sample can be used in this measurement as the
thickness of the test sample depends on the sample formation.

NOTE The measurement is not sensitive to the maximum dimensions of the test sample.
4.1.4 Procedure
Arrangement of antennas and the test sample are shown in Table 2, Table 3, Figure 5 and
Figure 6.
4.1.4.1 General
a) Loop antennas shall be arranged in a plane as shown in Figure 5.
b) When a loop antenna with slit is used, the slit of two antennas shall be arranged as
shown in Figure 6.
62333-2  IEC:2006 – 11 –
4.1.4.2 Measuring configuration
a) A pair of loop antennas shall be prepared as given in 4.1.2.
b) Connect the antennas to network analyzer through coaxial cables as shown in Figure 1.
c) Arrange the test sample and the antennas as shown in Figure 5 and Figure 6.
d) Measure transmission characteristics (S ), first without the test sample (S ), then with
21 21R
the test sample (S ).
21M
4.1.4.3 Calculation of R
da
Intra-decoupling ratio R is then calculated by the following formula:
da
R = S – S [dB]
da 21R 21M
where
S is the transmission characteristics (S ) without the test sample;
21R 21
is the transmission characteristics (S ) with the test sample.
S
21M 21
4.1.5 Expression of results
R shall be expressed.
da
4.2 Inter-decoupling ratio: R
de
4.2.1 Principle
This method is applied for evaluating the reduction of coupling between lines or circuit boards
by the NSS between them, at the frequency range from 100 MHz to 6 GHz.
A pair of antennas is employed. One is for noise source and the other is for receiver. An
electromagnetic interference actually observed in electronic equipment is simulated by the
measurement as shown in Figure 7.
NSS is placed approximately in the middle of the antennas. S between two antennas with
NSS is measured. And the coupling compared without NSS as a reference value, and
consequently, inter-decoupling ratio R (dB) can be obtained.
de
RF magnetic field generated by one antenna is coupled with another one (see Figure 8). By
setting the NSS, between the antennas, a part of the magnetic flux is led to the NSS, and the
coupling is reduced by the electromagnetic loss of the material.

– 12 – 62333-2  IEC:2006
Loop antennas
Network
analyzer
Test sample
Magnetic flux
Coaxial cable
IEC  648/06
Figure 7 – Schematic diagram of a pair of loop antennas and test sample

Loop antenna
Magnetic flux
Slit
Slit
Test sample
IEC  649/06
Figure 8 – Schematic diagram of a pair of antenna and test sample
4.2.2 Apparatus
Figure 7 shows the schematic diagram of the measuring method of inter-decoupling ratio.
NOTE The test sample and the loop antennas are set at least 30 mm away from any other materials except for
the coaxial cable, using low dielectric and low loss material such as the styrene foam and air gap.
4.2.2.1 Loop antenna
Small loop antennas defined in 4.1.2 shall be used.
A pair of loop antennas shall be held as shown in Figure 9. The dimensions of the loop
antennas are specified as shown in Table 4.

62333-2  IEC:2006 – 13 –
θ
Loop antennas
Test sample
θ
IEC  650/06
D is the distance between the centres of the loop antennas;
φ is the average diameter of the loop antenna;
a
θ is the angle from the plane perpendicular to the test sample.
Figure 9 – Schematic diagram of the measuring configuration
Table 4 – Dimensions of loop antennas
Distance D Angle θ
Diameter φ
a
mm radian
mm
a
6,0 ± 0,2 3,0 ± 0,2 ≤ π/18
a
≤ 10 degrees
Frequency response required by the antenna shall be in accordance with 4.1.2.
4.2.2.2 Network analyzer
A network analyzer shall be operated in accordance with 4.1.2.2.
4.2.3 Test sample
Test sample shall be in accordance with 4.1.3.
4.2.4 Procedure
Arrangements of the antennas and the test sample are shown in Table 1, Table 3 and Figure
9.
4.2.4.1 General
a) Loop antennas shall be arranged in a plane as shown in Figure 9.
b) When the loop antenna with slit is used, the slit of the two antennas shall be arranged as
shown in Figure 8.
φ
a
D
– 14 – 62333-2  IEC:2006
4.2.4.2 Measuring configuration
a) A pair of loop antennas shall be arranged as shown in 4.2.2.1.
b) Connect the antennas to the network analyzer through coaxial cables as shown in Figure 7.
c) Arrange the test sample and the antennas as shown in Figure 8 and Figure 9.
d) Measure transmission characteristics (S ), first without the test sample (S ) then
21 21R
with the test sample (S ).
21M
4.2.4.3 Calculation of R
de
Inter-decoupling ratio R is then calculated by the following formula:
de
R = S – S (dB)
de 21R 21M
where
S is the transmission characteristics (S ) without the test sample;
21R 21
S is the transmission characteristics (S ) with the test sample.
21M 21
4.2.5 Expression of results
R shall be expressed.
de
4.3 Transmission attenuation power ratio: R
tp
4.3.1 Principle
This method is for measuring the attenuation of conducting current noise along the PCB or
the other noise path achieved by the NSS installation. The MSL, which is used in the
microwave frequency, is employed as a transmission line for the noise, and the MSL
simulates a general noise path of the electronic equipment (see Figure 10).
4.3.2 Apparatus
The schematic diagram of the measuring method of a transmission attenuation power ratio;
R is shown in Figure 10.
tp
62333-2  IEC:2006 – 15 –
Dimensions in millimetres
54,40 ± 0,15
R 2,2
R 2,2
Strip conductor
50,00 ± 0,15
100,0 ± 0,8
Centre
conductor
Substrate
Ground plane
SMA
connector
Network analyzer
IEC  651/06
Figure 10 – Schematic diagram of the measuring method
for transmission attenuation power ratio R
tp
4.3.3 Test fixture
The dimensions of the test fixture, on which the strip conductor is printed, are shown in
Table 5. Both ends of the test fixture should be connected to the network analyzer via SMA
type connectors. The VSWR of the test fixture terminated with the other end should be
smaller than 1,5 within a measuring frequency range.
Table 5 – Dimensions of test fixture

Length Width Thickness
Material
mm mm mm
a b
Substrate 100,0 ± 0,8 50,0 ± 0,8 1,6 PTFE/Glass
a
Strip conductor 0,018 Cu
54,40 ± 0,15 4,40 ± 0,05
a
Ground plane
100,0 ± 0,8 50,0 ± 0,8 0,018 Cu
a
Typically
b
ε = 2,2 to 2,6
r
4.3.3.1 Network analyzer
A network analyzer shall be operated in accordance with 4.1.2.2.
4,40 ± 0,05
1,6
50,0 ± 0,8
– 16 – 62333-2  IEC:2006
4.3.4 Test sample
4.3.4.1 Dimension
The dimensions of the test sample for measuring R are shown in Table 6.
tp
Table 6 – Dimensions of test sample
Length L Width W
mm mm
≥ 100 ≥ 50
NOTE The measurement is not sensitive to the maximum dimensions of the test sample.
4.3.4.2 Attachment method on the test fixture
The test sample should be put and fixed on the whole test fixture by using one of the following
methods:
a) direct fixing:
the test sample may be fixed on the MSL test fixture when the test sample is adhesive or
with an adhesive layer;
b) fixing with adhesive:
when the test sample is not adhesive, the test sample shall be fixed on the MSL test
fixture with an appropriate adhesive that does not affect transmission characteristics of the
test fixture. The adhesive should be less than 0,1 mm in thickness and non-conductive.
The width and the length of the adhesive shall be equal to those of the test sample;
NOTE Example of adhesive: a double-sided adhesive tape with less than 0,1 mm in thickness.
c) fixing with spacer and weight:
in some cases, when the test sample does not have a self-adhesive layer, fixing with a
spacer and an appropriate weight can be used. In this method, the spacer shall be
inserted between the strip conductor and the sheets in advance. A polyethylene
terephthalate (PET) sheet, which does not affect transmission characteristics, is
favourable as the spacer. A spacer of 0,025 mm in thickness is required between the test
sample and the strip conductor. Furthermore, the test sample should be maintained in a
flat position by applying an appropriate weight. The mass 0,5 kg (5 N) is preferred and
should be supported by styrene foam board with a thickness of more than 10 mm in order
to avoid disturbance caused by the weight.
4.3.5 Procedure
4.3.5.1 Measurement system set-up
The measurement apparatus and the test sample(s) should be prepared in accordance with
4.3.2 and 4.3.4 in advance. A calibration of the network analyzer should be done at the end of
connectors of coaxial cables connected to the test fixture. Connect each end of the coaxial
cable to each port of the test fixture, respectively.
4.3.5.2 Reference measurement
Measure and save S and S data as a reference. Measured S and S are called S
11 21 11 21 11R
and S , respectively.
21R
62333-2  IEC:2006 – 17 –
4.3.5.3 Test sample measurement
The test sample should be placed on the test fixture in accordance with 4.3.4. Measure and
save S and S data as a sample characteristic. Measured S and S are called S and
11 21 11 21 11M
S , respectively.
21M
4.3.5.4 Calculation of R
tp
R shall be calculated by using the following formula:
tp
S /10 S /10
21M 11M
R =−10lg{ 10 /( 1−10 )} (dB)
tp
The calculated value shows attenuation due to the test sample. Data examples are shown in
Figures 11 a, b and c.
4.3.6 Expression of results
The following items shall be expressed:
a) R
tp;
b) Circuit parameters, S , S , S and S .
11R 21R 11M 21M
NOTE When the test sample has anisotropic properties, the measured direction should be given in the
manufacturer’s technical data.
S R
–10
–10
S M
–20
–20
–30
–30
S M
S R
–40
–40
–50
–50
0 2 4 6 8 10
0 2 4 6 8 10
Frequency  GHz
Frequency  GHz
IEC  653/06
IEC  652/06
Figure 11 b – Transmission loss
Figure 11 a – Return loss
0 2 4 6 8 10
Frequency  GHz
Frequency [GHz]
IEC  654/06
Figure 11c – Calculated R from S and S
tp 11M 21M
Figure 11 – Data examples of the measurement results
S dB
R  dB
tp
S dB
– 18 – 62333-2  IEC:2006
4.4 Radiation suppression ratio: R
rs
4.4.1 Principle
An MSL is used as a radiation source on this measurement. A current on a strip conductor of
the MSL generates electromagnetic wave radiation. Installation of the NSS on the strip
conductor reduces the current due to the electromagnetic loss of the NSS. As a result,
radiation from the MSL is suppressed.
4.4.2 Apparatus
The measurement system diagram is shown in Figure 12. The measurement system consists
of a test fixture, a signal source, a receiving antenna, a receiver and a test site.

Receiving
Test fixture
antenna
Turntable
Signal source Receiver
IEC  655/06
Figure 12 – Measurement system diagram of R
rs
4.4.2.1 Test fixture
The MSL with characteristic impedance of 50 Ω is used as the test fixture. A schematic
diagram of the test fixture is shown in Figure 13, and specifications of the test fixture are
shown in Figure 14, Table 7, respectively. The VSWR of the test fixture should be less
than 1,5.
Strip conductor
Substrate
Ground plane
Signal source 50 Ω termination
IEC  656/06
Figure 13 – Schematic diagram of test fixture

62333-2  IEC:2006 – 19 –
Dimensions in millimetres
54,40 ± 0,15
R 2,2
R 2,2
Strip conductor
50,00 ± 0,15
100,0 ± 0,8
Centre
conductor
Substrate
Ground plane
SMA
connector
50 Ω termination
IEC  657/06
Figure 14 – Size and structure of test fixture

Table 7 – Dimensions of test fixture
Length Width Thickness
Material
mm mm mm
a b
Substrate 100,0 ± 0,8 50,0 ± 0,8 1,6  PTFE/Glass
a
Strip conductor 0,018 Cu
54,40 ± 0,15 4,40 ± 0,05
a
Ground plane 0,018 Cu
100,0 ± 0,8 50,0 ± 0,8
a
Typically
b
ε = 2,2 to 2,6
r
4,40 ± 0,05
1,6
50,0 ± 0,8
– 20 – 62333-2  IEC:2006
4.4.2.2 Signal source
A spectrum analyzer with a tracking generator is favourable for this measurement. A network
analyzer may be used as alternative measuring equipment. Output power of the signal source
shall be in the range from 0 dBm to 10 dBm.
4.4.2.3 Receiving antenna
A receiving antenna shall be the broadband antenna in accordance with CISPR 16-1.
4.4.2.4 Receiver
A receiver shall be the spectrum analyzer in accordance with CISPR 16-1. A network analyzer
may be usable under the conditions described in 4.4.4.2 b) and 4.4.4.3 c).
4.4.2.5 Test site
A test site shall be the anechoic chamber or the open-area test site in accordance with
CISPR 22.
4.4.3 Test sample
4.4.3.1 Dimension
The width and length of the test sample are specified in Table 8. The thickness of the test
sample is not defined.
Table 8 – Dimensions of test sample
Length L Width W
mm mm
55,2 ± 0,65 4,7 ± 0,25
4.4.3.2 Attachment method on the test fixture
The test sample shall be fixed on the strip conductor as shown in Figure 15 by using one of
the following methods. The strip conductor shall be fully covered with the test sample:
a) direct fixing:
the test sample may be fixed on the strip conductor when the test sample is adhesive or
with an adhesive layer;
b) fixing with adhesive:
when the test sample is not adhesive, the test sample shall be fixed on the strip conductor
with the adhesive that does not affect transmission characteristics of the test fixture. Width
and length of the adhesive shall be equal to those of the test sample.
NOTE Example of adhesive: double-sided adhesive tape with less than 0,1 mm in thickness and non-
conductive.
62333-2  IEC:2006 – 21 –
Test sample
Strip conductor
Substrate
Ground plane
IEC  658/06
Figure 15 – Test sample attachment on test fixture
4.4.4 Procedure
4.4.4.1 Measurement system set-up
Measurement system shall be set up in accordance with 4.4.2 and CISPR 22.
4.4.4.2 Reference measurement
a) Test fixture set-up
The test fixture shall be set on the turntable in accordance with Figure 16. The strip
conductor of the test fixture shall be horizontal and the ground plane of the test fixture
shall be vertical. The reference level should be measured without a test sample.

Test fixture
Turntable
IEC  659/06
Figure 16 – Test fixture set-up on turntable
b) Measurement
Reference receiving power P shall be measured using peak-hold function of the receiver
in accordance with CISPR 22. The reference receiving power shall be measured in the
horizontal polarization.
– 22 – 62333-2  IEC:2006
4.4.4.3 Test sample measurement
a) Test sample attachment on the test fixture
The test sample shall be attached on the test fixture in accordance with 4.4.3.2.
b) Test fixture set-up
The test fixture shall be set on the turntable in accordance with Figure 16. The strip
conductor of the test fixture shall be horizontal and the ground plane of the test fixture
shall be vertical.
c) Measurement
Receiving power P shall be measured using peak-hold function of the receiver in
accordance with CISPR 22. The receiving power of horizontal polarization shall be
measured.
4.4.4.4 Calculation of R
rs
R shall be calculated using the following formula:
rs
R =−10 lg(P /P ) (dB)
rs 1 0
where
P is the receiving power at the reference measurement;
P is the receiving power at the test sample measurement.
4.4.5 Expression of results
The following items shall be expressed:
a) R
rs;
b) attachment condition of the test sample.

___________
– 24 – 62333-2  IEC:2006
SOMMAIRE
AVANT-PROPOS . 25
1 Domaine d’application . 27
2 Références normatives . 27
3 Généralités . 27
4 Méthodes de mesure . 28
4.1 Rapport d'intra-découplage: R . 28
da
4.2 Rapport d'inter-découplage R . 33
de
4.3 Rapport de puissance d'affaiblissement de transmission: R . 36
tp
4.4 Rapport de suppression de rayonnement: R . 40
rs
Figure 1 – Représentation schématique d'une paire d'antennes et d'une plaque
réduisant le bruit . 28
Figure 2 – Paire d'antennes et plaque réduisant le bruit (NSS) en essai . 29
Figure 3 – Réponse en fréquence du couplage entre une paire d'antennes . 29
Figure 4 – Exemples recommandés de petites antennes cadres pour la mesure . 30
Figure 5 – Vue en coupe de la configuration de mesure . 31
Figure 6 – Schéma de principe de la configuration de mesure . 32
Figure 7 – Représentation schématique d'une paire d'antennes cadres et d'un
échantillon d'essai . 34
Figure 8 – Représentation schématique d'une paire d'antennes et d'un échantillon
d'essai . 34
Figure 9 – Schéma de principe de la configuration de mesure . 35
Figure 10 – Représentation schématique de la méthode de mesure du rapport de
puissance d'affaiblissement de transmission R . 37
tp
Figure 11 – Exemples de données des résultats de mesure . 39
Figure 12 – Schéma du spécimen de mesure de R . 40
rs
Figure 13 – Représentation schématique d'un support d'essai . 41
Figure 14 – Taille et structure du support d'essai . 41
Figure 15 – Fixation de l'échantillon d'essai sur le support d'essai . 43
Figure 16 – Support d'essai monté sur un plateau tournant . 43

Tableau 1 – Limites et mérites des antennes recommandées. 31
Tableau 2 – Dimensions des antennes cadres . 31
Tableau 3 – Dimensions de l'échantillon d'essai . 32
Tableau 4 – Dimensions des antennes cadres . 35
Tableau 5 – Dimensions du support d'essai . 37
Tableau 6 – Dimensions de l'échantillon d'essai . 38
Tableau 7 – Dimensions du support d'essai . 42
Tableau 8 – Dimensions de l'échantillon d'essai . 42

62333-2  IEC:2006 – 25 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
PLAQUE RÉDUISANT LE BRUIT
DES DISPOSITIFS ET APPAREILS NUMÉRIQUES –

Partie 2: Méthodes de mesure
AVANT-PROPOS
1) La Commission Electrotechnique Internationale (CEI) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a
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IEC 62333-2 ®
Edition 1.1 2015-08
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Noise suppression sheet for digital devices and equipment –
Part 2: Measuring methods
Plaque réduisant le bruit des dispositifs et appareils numériques –
Partie 2: Méthodes de mesure
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IEC 62333-2 ®
Edition 1.1 2015-08
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Noise suppression sheet for digital devices and equipment –

Part 2: Measuring methods
Plaque réduisant le bruit des dispositifs et appareils numériques –

Partie 2: Méthodes de mesure
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.100.10 ISBN 978-2-8322-2836-4

IEC 62333-2 ®
Edition 1.1 2015-08
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Noise suppression sheet for digital devices and equipment –
Part 2: Measuring methods
Plaque réduisant le bruit des dispositifs et appareils numériques –
Partie 2: Méthodes de mesure
– 2 – IEC 62333-2:2006+AMD1:2015 CSV
© IEC 2015
CONTENTS
FO R EW O RD . 4
1 Sc op e . . 6
2 Normative references . 6
3 General . 6
4 Measuring methods . 7
4.1 Intra-decoupling ratio: R . 7
da
4.2 Inter-decoupling ratio: R . 12
de
4.3 Transmission attenuation power ratio: R . 15
tp
4.4 Radiation suppression ratio: R . 19
rs
4.5 Line-decoupling ratio: R . 23
dl
Figure 1 – Schematic diagram of a pair of antennas and NSS under test . 7
Figure 2 – A pair of antennas and NSS under test . 8
Figure 3 – Frequency response of coupling between a pair of antennas . 8
Figure 4 – Recommended examples of small loop antennas for the measurement . 9
Figure 5 – Cross-sectional view of the measuring configuration . 10
Figure 6 – Schematic diagram of the measuring configuration . 11
Figure 7 – Schematic diagram of a pair of loop antennas and test sample . 13
Figure 8 – Schematic diagram of a pair of antenna and test sample . 13
Figure 9 – Schematic diagram of the measuring configuration . 14
Figure 10 – Schematic diagram of the measuring method for transmission attenuation
power ratio R . 16
tp
Figure 11 – Data examples of the measurement results . 18
Figure 12 – Measurement system diagram of R . 19
rs
Figure 13 – Schematic diagram of test fixture . 19
Figure 14 – Size and structure of test fixture . 20
Figure 15 – Test sample attachment on test fixture . 22
Figure 16 – Test fixture set-up on turntable . 22
Figure 17 – Noise path . 24
Figure 18 – A test fixture for line decoupling measurement . 25
Figure 19 – Schematic diagram of MSL and loop antenna set-up . 25
Figure 20 – NSS, loop antenna and magnetic flux configuration . 26

Table 1 – Merits and limitations of the recommended antennas . 10
Table 2 – Dimensions of loop antennas . 10
Table 3 – Dimensions of test sample . 11
Table 4 – Dimensions of loop antennas . 14
Table 5 – Dimensions of test fixture . 16
Table 6 – Dimensions of test sample . 17
Table 7 – Dimensions of test fixture . 20
Table 8 – Dimensions of test sample . 21
Table 9 – Noise suppression effect classified as noise path and NSS position . 24

 IEC 2015
Table 10 – Dimensions of the MSL . 26
Table 11 – Dimensions of loop antenna . 26
Table 12 – Dimensions of the test sample . 27

– 4 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
NOISE SUPPRESSION SHEET
FOR DIGITAL DEVICES AND EQUIPMENT –
Part 2: Measuring methods
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
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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
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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.
This consolidated version of the official IEC Standard and its amendment has been prepared
for user convenience.
IEC 62333-2 edition 1.1 contains the first edition (2006-05) [documents 51/853/FDIS and 51/861/
RVD] and its amendment 1 (2015-08) [documents 51/1068/CDV and 51/1088/RVC].
In this Redline version, a vertical line in the margin shows where the technical content is
modified by amendment 1. Additions and deletions are displayed in red, with deletions
being struck through. A separate Final version with all changes accepted is available in this
publication.
 IEC 2015
International Standard IEC 62333-2 has been prepared IEC technical committee 51: Magnetic
components and ferrite materials.
This standard is to be used in conjunction with IEC 62333-1.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
IEC 62333 consists of the following parts, under the general title Noise suppression sheet for
digital devices and equipment:
Part 1: Definitions and general properties
Part 2: Measuring methods
The committee has decided that the contents of the base publication and its amendment will
remain unchanged until the stability 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.
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.
– 6 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
NOISE SUPPRESSION SHEET
FOR DIGITAL DEVICES AND EQUIPMENT –

Part 2: Measuring methods
1 Scope
This part of IEC 62333 specifies the methods for measuring the electromagnetic
characteristics of a noise suppression sheet. Those methods are intended to provide useful
and repeatable measurements to characterize the performance of the noise suppression
sheets, so that manufacturers and their customers are able to obtain the same results.
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 amendment) applies.
IEC 62333-1, Noise suppression sheet for digital devices and equipment – Part 1: Definitions
and general properties
CISPR 16-1, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1: Radio disturbance and immunity measuring apparatus
CISPR 22, Information technology equipment – Radio disturbance characteristics – Limits and
methods of measurement
3 General
Electromagnetic interference between electronic devices, and emission of radiation from
electronic devices are caused, in part, by RF current generated by active devices which are
driven at high frequency. Printed-circuit board (PCB), devices mounted on the PCB, and all
other connected circuits or cables can act as antennas to radiate the RF noise. Levels of the
electromagnetic interference and the emission are proportional to the RF current, and are also
affected significantly by PCB design, radiation efficiency of the antennas, and noise coupling
coefficients between the devices and the antennas.
The noise suppression sheet (NSS) is used for decoupling of the noise path, suppressing RF
noise current, and reducing radiation. The noise suppression effect of the NSS can be
evaluated by four parameters. They are defined as intra-decoupling ratio (R ), inter-
da
decoupling ratio (R ), transmission attenuation power ratio (R ) and radiation suppression
de tp
ratio (R ).
rs
A pair of antennas is held close to each other for the measuring intra-decoupling ratio (R )
da
and inter-decoupling ratio (R ). One antenna acts as a noise source and another one as a
de
receiver. Both decoupling ratios are derived from comparison before and after the NSS is
installed nearby the antennas. These measuring procedures represent practical configurations
of the NSS. Practically, the NSS is installed near the noise source or the noise interfered part,
inside of the electronic equipments.

 IEC 2015
A micro-strip line (MSL) test fixture is used for the measuring transmission attenuation power
ratio (R ) as a transmission line that would be a noise path. The ratio is derived from
tp
comparison before and after the NSS installation. This measuring procedure represents
another practical configuration that the NSS is utilized for reducing the RF current along the
transmission line.
The MSL test fixture is also used for measuring radiation suppression ratio (R ) as the
rs
antenna. The ratio is derived from a comparison before and after the NSS installation. This
measuring procedure represents another practical configuration that the NSS is utilized for
reducing the radiation from the antenna.
4 Measuring methods
4.1 Intra-decoupling ratio: R
da
4.1.1 Principle
The following measuring method is applied for evaluating a reduction of coupling between
lines or circuit boards on one side of the NSS, from 100 MHz to 6 GHz.
A pair of loop antennas is employed. One is for noise source and the other one for receiver.
They are simulating a general electromagnetic interference situation that often exists inside
electronic equipment (see Figure 1).
The NSS is placed so that the centre of the antenna pair comes to the centre of the NSS. The
coupling between two antennas with the NSS is measured, as well as the coupling without the
(dB) can be obtained.
NSS as a reference value. Consequently, intra-decoupling ratio R
da
RF magnetic field raised by one antenna is coupled with another one (see Figure 2a). By
setting the NSS, the antennas (see Figure 2b), a part of the magnetic flux is led to the NSS,
and the coupling is reduced by electromagnetic loss in the material.

Loop antennas
Network
NSS
analyzer
Magnetic flux
Coaxial cable
IEC  637/06
Figure 1 – Schematic diagram of a pair of antennas and NSS under test

– 8 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
Magnetic flux
NSS
IEC  638/06 IEC  639/06
Figure 2a – Loop antennas Figure 2b – NSS under test

Figure 2 – A pair of antennas and NSS under test
4.1.2 Apparatus
Figure 1 shows the schematic diagram of the measuring method of intra-decoupling ratio.
NOTE The test sample and the loop antennas are set at least 30 mm away from any other material except for the
coaxial cable, using low dielectric and low loss material such as the styrene foam and air gap.
Small loop antennas shall be used for the generation of the RF magnetic field and the
detection of the magnetic flux.
The S of the ideal loop antenna pair is proportional to the frequency. This means that S
21 21
increases 20 dB with the decade of frequency. The usable frequency range of the loop
antenna is defined by the deviation of S from the theoretical value. The deviation should be
less than ±3 dB as shown in Figure 3.

Theoretical
20 dB/decade
20 dB
+3 dB
20 dB
–3 dB
f 10f
f/10
Frequency
IEC  640/06
Figure 3 – Frequency response of coupling between a pair of antennas
Several loop antenna designs shown in Figure 4 are capable of achieving the 20 dB/decade
frequency response that defines a valid R /R measurement.
da de
4.1.2.1 Loop antenna
Recommended examples of the small antennas are shown in Figure 4. Merits and limitations
of recommended examples of the antennas are described in Table 1.

Coupling S
 IEC 2015
Slit ≤ f /10
a
Slit
•
Loop antenna
st rd
1 /3
Via hole
layer
Soldering
Substrate
Semi-rigid cable
nd
layer
50 Ω termination
Connector
Connector
IEC  641/06
IEC  642/06
Figure 4b – Shielded loop antenna
Figure 4a – Shielded multi-layered
with slit and 50 Ω termination
antenna with slit
Slit ≤ f /10
a
•
Ferrite
beads
Connector
Connector
IEC  643/06 IEC  644/06
Figure 4c – One turn antenna Figure 4d – Shielded coaxial
antenna with slit
with ferrite beads
Connector
Semi-rigid cable
Slit
Electrical shorting plate
50 Ω termination
IEC  645/06
Figure 4e – Shield loop antenna
with electrical shorting plate

Figure 4 – Recommended examples of small loop antennas for the measurement

– 10 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
Table 1 – Merits and limitations of the recommended antennas
Frequency range
Loop antenna type (approx.) Fabrication Materials
GHz
Shielded multi-layer antenna PCB manufacturing PCB material
a) 0,1 to 3
with slit process required Ex. FR-4
Shielded loop antenna with Engineering skills Semi-rigid cable
b) 0,1 to 6
required
50 Ω termination
One turn antenna with ferrite Easy Semi-rigid cable
c) beads 0,1 to 2 Ferrite beads
Ex. NiCuZn ferrite
Shielded coaxial antenna with Easy Semi-rigid cable
d) 0,1 to 2
slit
Shield loop antenna with Easy Semi-rigid cable
e) 0,1 to 6
electrical shorting plate
Slit width shown in Figures 4a), b), d) and e) shall be less than f /10, where f is average
a a
diameter of the loop antenna.
A pair of loop antennas shall be arranged as shown in Figure 5. The dimensions of loop
antennas are specified as shown in Table 2.

Test sample
D
θ θ
f
a
Loop antennas
IEC  646/06
D is the distance between centres of the loop antennas;
f is the average diameter of the loop antenna;
a
H is the clearance between test sample and the antenna surface;
θ is the angle between test sample and each loop antenna surface.
Figure 5 – Cross-sectional view of the measuring configuration
Table 2 – Dimensions of loop antennas
Distance D Clearance H Angle θ
Diameter f
a
mm mm mm radian
a
6,0 ± 0,2 3,0 ± 0,2 3,0 ± 0,2 ≤ π/18
a
≤ 10 degrees
H
 IEC 2015
4.1.2.2 Network analyzer
A network analyzer should be prepared both for signal source and signal receiver. A
calibration of the network analyzer should be done at the nearest point of loop antenna. The
combination of a signal generator and a receiver will be used as an alternative measuring
equipment.
4.1.3 Test sample
The dimensions of test samples are specified in Figure 6 and Table 3.

Loop antenna
Slit
Slit
W
Test sample
L
IEC  647/06
L is the length of test sample;
W is the width of test sample.
Figure 6 – Schematic diagram of the measuring configuration
Table 3 – Dimensions of test sample
Length L Width W
mm mm
≥ 40 ≥ 40
NOTE Any thickness of the test sample can be used in this measurement as the
thickness of the test sample depends on the sample formation.

NOTE The measurement is not sensitive to the maximum dimensions of the test sample.
4.1.4 Procedure
Arrangement of antennas and the test sample are shown in Table 2, Table 3, Figure 5 and
Figure 6.
4.1.4.1 General
a) Loop antennas shall be arranged in a plane as shown in Figure 5.
b) When a loop antenna with slit is used, the slit of two antennas shall be arranged as
shown in Figure 6.
– 12 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
4.1.4.2 Measuring configuration
a) A pair of loop antennas shall be prepared as given in 4.1.2.
b) Connect the antennas to network analyzer through coaxial cables as shown in Figure 1.
c) Arrange the test sample and the antennas as shown in Figure 5 and Figure 6.
d) Measure transmission characteristics (S ), first without the test sample (S ), then with
21 21R
the test sample (S ).
21M
4.1.4.3 Calculation of R
da
Intra-decoupling ratio R is then calculated by the following formula:
da
R = S – S [dB]
da 21R 21M
where
S is the transmission characteristics (S ) without the test sample;
21R 21
is the transmission characteristics (S ) with the test sample.
S
21M 21
4.1.5 Expression of results
R shall be expressed.
da
4.2 Inter-decoupling ratio: R
de
4.2.1 Principle
This method is applied for evaluating the reduction of coupling between lines or circuit boards
by the NSS between them, at the frequency range from 100 MHz to 6 GHz.
A pair of antennas is employed. One is for noise source and the other is for receiver. An
electromagnetic interference actually observed in electronic equipment is simulated by the
measurement as shown in Figure 7.
NSS is placed approximately in the middle of the antennas. S between two antennas with
NSS is measured. And the coupling compared without NSS as a reference value, and
consequently, inter-decoupling ratio R (dB) can be obtained.
de
RF magnetic field generated by one antenna is coupled with another one (see Figure 8). By
setting the NSS, between the antennas, a part of the magnetic flux is led to the NSS, and the
coupling is reduced by the electromagnetic loss of the material.

 IEC 2015
Loop antennas
Network
analyzer
Test sample
Magnetic flux
Coaxial cable
IEC  648/06
Figure 7 – Schematic diagram of a pair of loop antennas and test sample

Loop antenna
Magnetic flux
Slit
Slit
Test sample
IEC  649/06
Figure 8 – Schematic diagram of a pair of antenna and test sample
4.2.2 Apparatus
Figure 7 shows the schematic diagram of the measuring method of inter-decoupling ratio.
NOTE The test sample and the loop antennas are set at least 30 mm away from any other materials except for
the coaxial cable, using low dielectric and low loss material such as the styrene foam and air gap.
4.2.2.1 Loop antenna
Small loop antennas defined in 4.1.2 shall be used.
A pair of loop antennas shall be held as shown in Figure 9. The dimensions of the loop
antennas are specified as shown in Table 4.

– 14 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
θ
Loop antennas
Test sample
θ
IEC  650/06
D is the distance between the centres of the loop antennas;
f is the average diameter of the loop antenna;
a
θ is the angle from the plane perpendicular to the test sample.
Figure 9 – Schematic diagram of the measuring configuration
Table 4 – Dimensions of loop antennas
Distance D Angle θ
Diameter f
a
mm radian
mm
a
6,0 ± 0,2 3,0 ± 0,2 ≤ π/18
a
≤ 10 degrees
Frequency response required by the antenna shall be in accordance with 4.1.2.
4.2.2.2 Network analyzer
A network analyzer shall be operated in accordance with 4.1.2.2.
4.2.3 Test sample
Test sample shall be in accordance with 4.1.3.
4.2.4 Procedure
Arrangements of the antennas and the test sample are shown in Table 1, Table 3 and Figure
9.
4.2.4.1 General
a) Loop antennas shall be arranged in a plane as shown in Figure 9.
b) When the loop antenna with slit is used, the slit of the two antennas shall be arranged as
shown in Figure 8.
f
a
D
 IEC 2015
4.2.4.2 Measuring configuration
a) A pair of loop antennas shall be arranged as shown in 4.2.2.1.
b) Connect the antennas to the network analyzer through coaxial cables as shown in Figure 7.
c) Arrange the test sample and the antennas as shown in Figure 8 and Figure 9.
d) Measure transmission characteristics (S ), first without the test sample (S ) then
21 21R
with the test sample (S ).
21M
4.2.4.3 Calculation of R
de
Inter-decoupling ratio R is then calculated by the following formula:
de
R = S – S (dB)
de 21R 21M
where
S is the transmission characteristics (S ) without the test sample;
21R 21
S is the transmission characteristics (S ) with the test sample.
21M 21
4.2.5 Expression of results
R shall be expressed.
de
4.3 Transmission attenuation power ratio: R
tp
4.3.1 Principle
This method is for measuring the attenuation of conducting current noise along the PCB or
the other noise path achieved by the NSS installation. The MSL, which is used in the
microwave frequency, is employed as a transmission line for the noise, and the MSL
simulates a general noise path of the electronic equipment (see Figure 10).
4.3.2 Apparatus
The schematic diagram of the measuring method of a transmission attenuation power ratio;
R is shown in Figure 10.
tp
– 16 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
Dimensions in millimetres
54,40 ± 0,15
R 2,2
R 2,2
Strip conductor
50,00 ± 0,15
100,0 ± 0,8
Centre
conductor
Substrate
Ground plane
SMA
connector
Network analyzer
IEC  651/06
Figure 10 – Schematic diagram of the measuring method
for transmission attenuation power ratio R
tp
4.3.3 Test fixture
The dimensions of the test fixture, on which the strip conductor is printed, are shown in
Table 5. Both ends of the test fixture should be connected to the network analyzer via SMA
type connectors. The VSWR of the test fixture terminated with the other end should be
smaller than 1,5 within a measuring frequency range.
Table 5 – Dimensions of test fixture

Length Width Thickness
Material
mm mm mm
a b
Substrate 100,0 ± 0,8 50,0 ± 0,8 1,6 PTFE/Glass
a
Strip conductor 0,018 Cu
54,40 ± 0,15 4,40 ± 0,05
a
Ground plane
100,0 ± 0,8 50,0 ± 0,8 0,018 Cu
a
Typically
b
ε = 2,2 to 2,6
r
4.3.3.1 Network analyzer
A network analyzer shall be operated in accordance with 4.1.2.2.
4,40 ± 0,05
1,6
50,0 ± 0,8
 IEC 2015
4.3.4 Test sample
4.3.4.1 Dimension
The dimensions of the test sample for measuring R are shown in Table 6.
tp
Table 6 – Dimensions of test sample
Length L Width W
mm mm
≥ 100 ≥ 50
NOTE The measurement is not sensitive to the maximum dimensions of the test sample.
4.3.4.2 Attachment method on the test fixture
The test sample should be put and fixed on the whole test fixture by using one of the following
methods:
a) direct fixing:
the test sample may be fixed on the MSL test fixture when the test sample is adhesive or
with an adhesive layer;
b) fixing with adhesive:
when the test sample is not adhesive, the test sample shall be fixed on the MSL test
fixture with an appropriate adhesive that does not affect transmission characteristics of the
test fixture. The adhesive should be less than 0,1 mm in thickness and non-conductive.
The width and the length of the adhesive shall be equal to those of the test sample;
NOTE Example of adhesive: a double-sided adhesive tape with less than 0,1 mm in thickness.
c) fixing with spacer and weight:
in some cases, when the test sample does not have a self-adhesive layer, fixing with a
spacer and an appropriate weight can be used. In this method, the spacer shall be
inserted between the strip conductor and the sheets in advance. A polyethylene
terephthalate (PET) sheet, which does not affect transmission characteristics, is
favourable as the spacer. A spacer of 0,025 mm in thickness is required between the test
sample and the strip conductor. Furthermore, the test sample should be maintained in a
flat position by applying an appropriate weight. The mass 0,5 kg (5 N) is preferred and
should be supported by styrene foam board with a thickness of more than 10 mm in order
to avoid disturbance caused by the weight.
4.3.5 Procedure
4.3.5.1 Measurement system set-up
The measurement apparatus and the test sample(s) should be prepared in accordance with
4.3.2 and 4.3.4 in advance. A calibration of the network analyzer should be done at the end of
connectors of coaxial cables connected to the test fixture. Connect each end of the coaxial
cable to each port of the test fixture, respectively.
4.3.5.2 Reference measurement
Measure and save S and S data as a reference. Measured S and S are called S
11 21 11 21 11R
and S , respectively.
21R
– 18 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
4.3.5.3 Test sample measurement
The test sample should be placed on the test fixture in accordance with 4.3.4. Measure and
save S and S data as a sample characteristic. Measured S and S are called S and
11 21 11 21 11M
S , respectively.
21M
4.3.5.4 Calculation of R
tp
R shall be calculated by using the following formula:
tp
S /10 S /10
21M 11M
R =−10lg{ 10 /( 1−10 )} (dB)
tp
The calculated value shows attenuation due to the test sample. Data examples are shown in
Figures 11 a, b and c.
4.3.6 Expression of results
The following items shall be expressed:
a) R
tp;
b) Circuit parameters, S , S , S and S .
11R 21R 11M 21M
NOTE When the test sample has anisotropic properties, the measured direction should be given in the
manufacturer’s technical data.
S R
–10
–10
S M
–20
–20
–30
–30
S M
S R
–40
–40
–50
–50
0 2 4 6 8 10
0 2 4 6 8 10
Frequency  GHz
Frequency  GHz
IEC  653/06
IEC  652/06
Figure 11 b – Transmission loss
Figure 11 a – Return loss
0 2 4 6 8 10
Frequency  GHz
Frequency [GHz]
IEC  654/06
Figure 11c – Calculated R from S and S
tp 11M 21M
Figure 11 – Data examples of the measurement results
S dB
R  dB
tp
S dB
 IEC 2015
4.4 Radiation suppression ratio: R
rs
4.4.1 Principle
An MSL is used as a radiation source on this measurement. A current on a strip conductor of
the MSL generates electromagnetic wave radiation. Installation of the NSS on the strip
conductor reduces the current due to the electromagnetic loss of the NSS. As a result,
radiation from the MSL is suppressed.
4.4.2 Apparatus
The measurement system diagram is shown in Figure 12. The measurement system consists
of a test fixture, a signal source, a receiving antenna, a receiver and a test site.

Receiving
Test fixture
antenna
Turntable
Signal source Receiver
IEC  655/06
Figure 12 – Measurement system diagram of R
rs
4.4.2.1 Test fixture
The MSL with characteristic impedance of 50 Ω is used as the test fixture. A schematic
diagram of the test fixture is shown in Figure 13, and specifications of the test fixture are
shown in Figure 14, Table 7, respectively. The VSWR of the test fixture should be less
than 1,5.
Strip conductor
Substrate
Ground plane
Signal source 50 Ω termination
IEC  656/06
Figure 13 – Schematic diagram of test fixture

– 20 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
Dimensions in millimetres
54,40 ± 0,15
R 2,2
R 2,2
Strip conductor
50,00 ± 0,15
100,0 ± 0,8
Centre
conductor
Substrate
Ground plane
SMA
connector
50 Ω termination
IEC  657/06
Figure 14 – Size and structure of test fixture

Table 7 – Dimensions of test fixture
Length Width Thickness
Material
mm mm mm
a b
Substrate 100,0 ± 0,8 50,0 ± 0,8 1,6  PTFE/Glass
a
Strip conductor 0,018 Cu
54,40 ± 0,15 4,40 ± 0,05
a
Ground plane 0,018 Cu
100,0 ± 0,8 50,0 ± 0,8
a
Typically
b
ε = 2,2 to 2,6
r
4,40 ± 0,05
1,6
50,0 ± 0,8
 IEC 2015
4.4.2.2 Signal source
A spectrum analyzer with a tracking generator is favourable for this measurement. A network
analyzer may be used as alternative measuring equipment. Output power of the signal source
shall be in the range from 0 dBm to 10 dBm.
4.4.2.3 Receiving antenna
A receiving antenna shall be the broadband antenna in accordance with CISPR 16-1.
4.4.2.4 Receiver
A receiver shall be the spectrum analyzer in accordance with CISPR 16-1. A network analyzer
may be usable under the conditions described in 4.4.4.2 b) and 4.4.4.3 c).
4.4.2.5 Test site
A test site shall be the anechoic chamber or the open-area test site in accordance with
CISPR 22.
4.4.3 Test sample
4.4.3.1 Dimension
The width and length of the test sample are specified in Table 8. The thickness of the test
sample is not defined.
Table 8 – Dimensions of test sample
Length L Width W
mm mm
55,2 ± 0,65 4,7 ± 0,25
4.4.3.2 Attachment method on the test fixture
The test sample shall be fixed on the strip conductor as shown in Figure 15 by using one of
the following methods. The strip conductor shall be fully covered with the test sample:
a) direct fixing:
the test sample may be fixed on the strip conductor when the test sample is adhesive or
with an adhesive layer;
b) fixing with adhesive:
when the test sample is not adhesive, the test sample shall be fixed on the strip conductor
with the adhesive that does not affect transmission characteristics of the test fixture. Width
and length of the adhesive shall be equal to those of the test sample.
NOTE Example of adhesive: double-sided adhesive tape with less than 0,1 mm in thickness and non-
conductive.
– 22 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
Test sample
Strip conductor
Substrate
Ground plane
IEC  658/06
Figure 15 – Test sample attachment on test fixture
4.4.4 Procedure
4.4.4.1 Measurement system set-up
Measurement system shall be set up in accordance with 4.4.2 and CISPR 22.
4.4.4.2 Reference measurement
a) Test fixture set-up
The test fixture shall be set on the turntable in accordance with Figure 16. The strip
conductor of the test fixture shall be horizontal and the ground plane of the test fixture
shall be vertical. The reference level should be measured without a test sample.

Test fixture
Turntable
IEC  659/06
Figure 16 – Test fixture set-up on turntable
b) Measurement
Reference receiving power P shall be measured using peak-hold function of the receiver
in accordance with CISPR 22. The reference receiving power shall be measured in the
horizontal polarization.
 IEC 2015
4.4.4.3 Test sample measurement
a) Test sample attachment on the test fixture
The test sample shall be attached on the test fixture in accordance with 4.4.3.2.
b) Test fixture set-up
The test fixture shall be set on the turntable in accordance with Figure 16. The strip
conductor of the test fixture shall be horizontal and the ground plane of the test fixture
shall be vertical.
c) Measurement
Receiving power P shall be measured using peak-hold function of the receiver in
accordance with CISPR 22. The receiving power of horizontal polarization shall be
measured.
4.4.4.4 Calculation of R
rs
R shall be calculated using the following formula:
rs
R =−10 lg(P /P ) (dB)
rs 1 0
where
P is the receiving power at the reference measurement;
P is the receiving power at the test sample measurement.
4.4.5 Expression of results
The following items shall be expressed:
a) R
rs;
b) attachment condition of the test sample.
4.5 Line-decoupling ratio: R
dl
4.5.1 General
This standard has provided for the measuring method of
① the intra-decoupling ratio (R ),
da
② the inter-decoupling ratio (R ),
de
③ the transmission attenuation power ratio (R ) and
tp
④ the radiation suppression ratio (R ) in 4.1 to 4.4.
rs
Subclause 4.5 provides
⑤ the line-decoupling ratio (R ).
dl
The diagrammatic illustration of each noise suppression effect is shown in the following
Table 9 and Figure 17.
– 24 – IEC 62333-2:2006+AMD1:2015 CSV
 IEC 2015
Table 9 – Noise suppression effect classified as noise path and NSS position
Victim Near field coupling Conduction Radiation
Part (component) Line
Line Far
plane field
Same Opposite Line in
Agressor side side vicinity
① ② ⑤
Part
Intra- Inter- Line
(component)
③ ④
decoupling decoupling decoupling
Transmission Radiation
⑤
attenuation suppression
Line ⑥ Line ⑦
decoupling
Chassis
Cable, FPC ④
⑤
③
③
PCB
Aggressor Victim
(part)
⑥
②
⑤ Line
① ⑦
Aggressor
Victim
decoupling
Victim Aggressor
PCB
(line) (line)
IEC
Figure 17 – Noise path
4.5.2 Principle
The following method is applied to evaluate the reduction of coupling between a line and (a)
part(s) on both sides of the NSS, from 100
...