EN 61000-4-3:2006

SLOVENSKI SIST EN 61000-4-3:2006

STANDARD
september 2006
Elektromagnetna združljivost (EMC) – 4-3. del: Preskusne in merilne tehnike –
Preskušanje odpornosti proti sevanim radiofrekvenčnim elektromagnetnim
poljem (IEC 61000-4-3:2006)
Electromagnetic compatibility (EMC) - Part 4-3: Testing and measurement
techniques - Radiated, radio-frequency, electromagnetic field immunity test (IEC
61000-4-3:2006)
ICS 33.100.20 Referenčna številka
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

EUROPEAN STANDARD
EN 61000-4-3
NORME EUROPÉENNE
May 2006
EUROPÄISCHE NORM
ICS 33.100.20 Supersedes EN 61000-4-3:2002 + A1:2002 + IS1:2004

English version
Electromagnetic compatibility (EMC)
Part 4-3: Testing and measurement techniques -
Radiated, radio-frequency, electromagnetic field immunity test
(IEC 61000-4-3:2006)
Compatibilité électromagnétique (CEM) Elektromagnetische Verträglichkeit (EMV)
Partie 4-3: Techniques d'essai Teil 4-3: Prüf- und Messverfahren -
et de mesure - Prüfung der Störfestigkeit
Essai d'immunité aux champs gegen hochfrequente
électromagnétiques rayonnés elektromagnetische Felder
aux fréquences radioélectriques (IEC 61000-4-3:2006)
(CEI 61000-4-3:2006)
This European Standard was approved by CENELEC on 2006-03-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

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

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

© 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61000-4-3:2006 E
Foreword
The text of document 77B/485/FDIS, future edition 3 of IEC 61000-4-3, prepared by SC 77B, High
frequency phenomena, of IEC TC 77, Electromagnetic compatibility, was submitted to the IEC-CENELEC
parallel vote and was approved by CENELEC as EN 61000-4-3 on 2006-03-01.
This European Standard supersedes EN 61000-4-3:2002 + A1:2002 + IS1:2004.
The test frequency range may be extended up to 6 GHz to take acount of new services. The calibration of
the field as well as the checking of power amplifier linearity of the immunity chain are specified.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2006-12-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2009-03-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61000-4-3:2006 was approved by CENELEC as a European
Standard without any modification.
__________
- 3 - EN 61000-4-3:2006
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year
1)
IEC 60050-161 International Electrotechnical Vocabulary - -
-
(IEV)
Chapter 161: Electromagnetic compatibility

1)
IEC 61000-4-6 Electromagnetic compatibility (EMC) -
-
-
Part 4-6: Testing and measurement
techniques - Immunity to conducted
disturbances, induced by radio-frequency
fields
1)
Undated reference.
IEC 61000-4-3
Edition 3. 2006-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
BASIC EMC PUBLICATION
PUBLICATION FONDAMENTALE EN CEM
Electromagnetic compatibility (EMC) –
Part 4-3: Testing and measurement techniques – Radiated, radio-frequency,
electromagnetic field immunity test
Compatibilité électromagnétique (CEM) –
Partie 4-3: Techniques d'essai et de mesure – Essai d'immunité aux champs
électromagnétiques rayonnés aux fréquences radioélectriques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XA
CODE PRIX
ICS 33.100.20 ISBN 2-8318-8487-X

61000-4-3 ¤ IEC:2006 –– 3 2 – – 61000-4-3 © IEC:2006
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope and object.7
2 Normative references .7
3 Terms and definitions .8
4 General .11
5 Test levels.11
5.1 Test levels related to general purposes .12
5.2 Test levels related to the protection against RF emissions from digital radio
telephones and other RF emitting devices .12
6 Test equipment.13
6.1 Description of the test facility .13
6.2 Calibration of field .14
7 Test setup .19
7.1 Arrangement of table-top equipment.19
7.2 Arrangement of floor-standing equipment .19
7.3 Arrangement of wiring .20
7.4 Arrangement of human body-mounted equipment.20
8 Test procedure .20
8.1 Laboratory reference conditions .20
8.2 Execution of the test.21
9 Evaluation of test results .22
10 Test report.22
Annex A (informative) Rationale for the choice of modulation for tests related to the
protection against RF emissions from digital radio telephones .31
Annex B (informative) Field generating antennas .36
Annex C (informative) Use of anechoic chambers .37
Annex D (informative) Amplifier non-linearity and example for the calibration
procedure according to 6.2 .40
Annex E (informative) Guidance for product committees on the selection of test levels .45
Annex F (informative) Selection of test methods .48
Annex G (informative) Description of the environment.49
Annex H (normative) Alternative illumination method for frequencies above 1 GHz
(“independent windows method”) .54

61000-4-3 © IEC:200661000-4-3 ¤ IEC:2006 –– 5 3 – –
Figure 1 – Definition of the test level and the waveshapes occurring at the output of
the signal generator .24
Figure 2 – Example of suitable test facility .25
Figure 3 – Calibration of field.26
Figure 4 – Calibration of field, dimensions of the uniform field area .27
Figure 5 – Example of test setup for floor-standing equipment .28
Figure 6 – Example of test setup for table-top equipment.29
Figure 7 – Measuring setup .30
Figure C.1 − Multiple reflections in an existing small anechoic chamber.38
Figure C.2 − Most of the reflected waves are eliminated .39
Figure D.1 − Measuring positions of the uniform field area.42
Figure H.1 – Examples of division of the calibration area into 0,5 m × 0,5 m windows .55
Figure H.2 – Example of illumination of successive windows.56
Table 1 – Test levels related to general purpose, digital radio telephones and other RF
emitting devices.11
Table 2 – Requirements for uniform field area for application of full illumination, partial
illumination and independent windows method.15
Table A.1 − Comparison of modulation methods .32
Table A.2 − Relative interference levels .33
Table A.3 − Relative immunity levels.34
Table D.1 – Forward power values measured according to the constant field strength
calibration method .43
Table D.2 – Forward power values sorted according to rising value and evaluation of
the measuring result .43
Table D.3 – Forward power and field strength values measured according to the
constant power calibration method.44
Table D.4 – Field strength values sorted according to rising value and evaluation of the
measuring result .44
Table E.1 – Examples of test levels, associated protection distances and suggested
performance criteria.47
Table G.1 – Mobile and portable units.51
Table G.2 – Base stations.52
Table G.3 – Other RF devices.53

61000-4-3 ¤ IEC:2006 –– 7 4 – – 61000-4-3 © IEC:2006
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_________
ELECTROMAGNETIC COMPATIBILITY (EMC) –
Part 4-3: Testing and measurement techniques –
Radiated, radio-frequency, electromagnetic field immunity test
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61000-4-3 has been prepared by subcommittee 77B: High
frequency phenomenon, of IEC technical committee 77: Electromagnetic compatibility.
It forms part 4-3 of IEC 61000. It has the status of a basic EMC publication in accordance with
IEC Guide 107, Electromagnetic compatibility – Guide to the drafting of electromagnetic
compatibility publications.
This third edition cancels and replaces the first edition published in 2002 and its amendment 1
(2002), and constitutes a technical revision. The test frequency range may be extended up to
6 GHz to take account of new services. The calibration of the field as well as the checking of
power amplifier linearity of the immunity chain are specified.

61000-4-3 © IEC:200661000-4-3 ¤ IEC:2006 –– 9 5 – –
The text of this standard is based on the following documents:
FDIS Report on voting
77B/485/FDIS 77B/500/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.
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.
61000-4-3 ¤ IEC:2006 –– 11 6 – – 61000-4-3 © IEC:2006
INTRODUCTION
This standard is part of the IEC 61000 series, according to the following structure:
Part 1: General
General considerations (introduction, fundamental principles)
Definitions, terminology
Part 2: Environment
Description of the environment
Classification of the environment
Compatibility levels
Part 3: Limits
Emission limits
Immunity limits (in so far as they do not fall under the responsibility of the product committees)
Part 4: Testing and measurement techniques
Measurement techniques
Testing techniques
Part 5: Installation and mitigation guidelines
Installation guidelines
Mitigation methods and devices
Part 6: Generic standards
Part 9: Miscellaneous
Each part is further subdivided into several parts, published either as international standards
or as technical specifications or technical reports, some of which have already been published
as sections. Others will be published with the part number followed by a dash and a second
number identifying the subdivision (example: 61000-6-1).
This part is an International Standard which gives immunity requirements and test procedures
related to radiated, radio-frequency, electromagnetic fields.

61000-4-3 © IEC:200661000-4-3 ¤ IEC:2006 –– 13 7 – –
ELECTROMAGNETIC COMPATIBILITY (EMC) –
Part 4-3: Testing and measurement techniques –
Radiated, radio-frequency, electromagnetic field immunity test
1 Scope and object
This part of IEC 61000 is applicable to the immunity requirements of electrical and electronic
equipment to radiated electromagnetic energy. It establishes test levels and the required test
procedures.
The object of this standard is to establish a common reference for evaluating the immunity of
electrical and electronic equipment when subjected to radiated, radio-frequency electro-
magnetic fields. The test method documented in this part of IEC 61000 describes a consistent
method to assess the immunity of an equipment or system against a defined phenomenon.
NOTE 1 As described in IEC Guide 107, this is a basic EMC publication for use by product committees of the IEC.
As also stated in Guide 107, the IEC product committees are responsible for determining whether this immunity
test standard should be applied or not, and if applied, they are responsible for determining the appropriate test
levels and performance criteria. TC 77 and its sub-committees are prepared to co-operate with product committees
in the evaluation of the value of particular immunity tests for their products.
This part deals with immunity tests related to the protection against RF electromagnetic fields
from any source.
Particular considerations are devoted to the protection against radio-frequency emissions
from digital radiotelephones and other RF emitting devices.
NOTE 2 Test methods are defined in this part for evaluating the effect that electromagnetic radiation has on the
equipment concerned. The simulation and measurement of electromagnetic radiation is not adequately exact for
quantitative determination of effects. The test methods defined are structured for the primary objective of
establishing adequate repeatability of results at various test facilities for qualitative analysis of effects.
This standard is an independent test method. Other test methods may not be used as
substitutes for claiming compliance with this standard.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60050(161), International Electrotechnical Vocabulary (IEV) – Chapter 161: Electro-
magnetic compatibility
IEC 61000-4-6, Electromagnetic compatibility (EMC) – Part 4-6: Testing and measurement
techniques – Immunity to conducted disturbances, induced by radio-frequency fields

61000-4-3 ¤ IEC:2006 –– 15 8 – – 61000-4-3 © IEC:2006
3 Terms and definitions
For the purposes of this part of IEC 61000, the following definitions, together with those in
IEC 60050(161) apply.
3.1
amplitude modulation
process by which the amplitude of a carrier wave is varied following a specified law
3.2
anechoic chamber
shielded enclosure which is lined with radio-frequency absorbers to reduce reflections from
the internal surfaces
3.2.1
fully anechoic chamber
shielded enclosure whose internal surfaces are totally lined with anechoic material
3.2.2
semi-anechoic chamber
shielded enclosure where all internal surfaces are covered with anechoic material with the
exception of the floor, which shall be reflective (ground plane)
3.2.3
modified semi-anechoic chamber
semi-anechoic chamber which has additional absorbers installed on the ground plane
3.3
antenna
transducer which either emits radio-frequency power into space from a signal source or
intercepts an arriving electromagnetic field, converting it into an electrical signal
3.4
balun
device for transforming an unbalanced voltage to a balanced voltage or vice versa
[IEV 161-04-34]
3.5
continuous waves (CW)
electromagnetic waves, the successive oscillations of which are identical under steady-state
conditions, which can be interrupted or modulated to convey information
3.6
electromagnetic (EM) wave
radiant energy produced by the oscillation of an electric charge characterized by oscillation of
the electric and magnetic fields
3.7
far field
region where the power flux density from an antenna approximately obeys an inverse square
law of the distance.
For a dipole this corresponds to distances greater than λ/2π, where λ is the wavelength of the
radiation
61000-4-3 © IEC:200661000-4-3 ¤ IEC:2006 –– 17 9 – –
3.8
field strength
The term "field strength" is applied only to measurements made in the far field. The
measurement may be of either the electric or the magnetic component of the field and may be
expressed as V/m, A/m or W/m ; any one of these may be converted into the others.
NOTE For measurements made in the near field, the term "electric field strength" or "magnetic field strength" is
used according to whether the resultant electric or magnetic field, respectively, is measured. In this field region,
the relationship between the electric and magnetic field strength and distance is complex and difficult to predict,
being dependent on the specific configuration involved. Inasmuch as it is not generally feasible to determine the
time and space phase relationship of the various components of the complex field, the power flux density of the
field is similarly indeterminate.
3.9
frequency band
continuous range of frequencies extending between two limits
3.10
E
c
field strength applied for calibration
3.11
E
t
carrier field strength applied for testing
3.12
full illumination
test method in which the EUT face being tested fits completely within the UFA (Uniform Field
Area).
This test method may be applied for all test frequencies
3.13
human body-mounted equipment
equipment which is intended for use when attached to or held in close proximity to the human
body.
This term includes hand-held devices which are carried by people while in operation (e.g.
pocket devices) as well as electronic aid devices and implants
3.14
independent windows method
test method (using 0,5 m × 0,5 m UFA) in which the EUT face being tested does not fit
completely within the UFA.
This test method may be applied for test frequencies greater than 1 GHz
3.15
induction field
predominant electric and/or magnetic field existing at a distance d < λ/2π, where λ is the
wavelength, and the physical dimensions of the source are much smaller than distance d
3.16
intentional RF emitting device
device which radiates (transmits) an electromagnetic field intentionally. Examples include
digital mobile telephones and other radio devices

61000-4-3 ¤ IEC:2006 –– 19 10 – – 61000-4-3 © IEC:2006
3.17
isotropic
having properties of equal values in all directions
3.18
maximum RMS value
highest short-term RMS value of a modulated RF signal during an observation time of one
modulation period.
The short-term RMS is evaluated over a single carrier cycle. For example, in Figure 1b), the
maximum RMS voltage is:
V = V / (2 × 2 ) = 1,8 V
maximum RMS p-p
3.19
non-constant envelope modulation
RF modulation schemes in which the amplitude of the carrier wave varies slowly in time
compared with the period of the carrier itself. Examples include conventional amplitude
modulation and TDMA
3.20
Pc
forward power needed to establish the calibration field strength
3.21
partial illumination
test method (using a minimum sized UFA of 1,5 × 1,5 m) in which the EUT face being tested
does not fit completely within the UFA.
This test method may be applied for all test frequencies.
3.22
polarization
orientation of the electric field vector of a radiated field
3.23
shielded enclosure
screened or solid metal housing designed expressly for the purpose of isolating the internal
from the external electromagnetic environment. The purpose is to prevent outside ambient
electromagnetic fields from causing performance degradation and to prevent emission from
causing interference to outside activities
3.24
sweep
continuous or incremental traverse over a range of frequencies
3.25
TDMA (time division multiple access)
time multiplexing modulation scheme which places several communication channels on the
same carrier wave at an allocated frequency. Each channel is assigned a time slot during
which, if the channel is active, the information is transmitted as a pulse of RF power. If the
channel is not active no pulse is transmitted, thus the carrier envelope is not constant. During
the pulse, the amplitude is constant and the RF carrier is frequency- or phase-modulated

61000-4-3 © IEC:200661000-4-3 ¤ IEC:2006 –– 21 11 – –
3.26
transceiver
combination of radio transmitting and receiving equipment in a common housing
3.27
uniform field area (UFA)
hypothetical vertical plane of the field calibration in which variations are acceptably small.
The purpose of field calibration is to ensure the validity of the test result. See 6.2
4 General
Most electronic equipment is, in some manner, affected by electromagnetic radiation. This
radiation is frequently generated by such general purpose sources as the small hand-held
radio transceivers that are used by operating, maintenance and security personnel, fixed-
station radio and television transmitters, vehicle radio transmitters, and various industrial
electromagnetic sources.
In recent years there has been a significant increase in the use of radio telephones and other
RF emitting devices operating at frequencies between 0,8 GHz and 6 GHz. Many of these
services use modulation techniques with a non-constant envelope (e.g. TDMA). See 5.2.
In addition to electromagnetic energy deliberately generated, there is also radiation caused by
devices such as welders, thyristors, fluorescent lights, switches operating inductive loads, etc.
For the most part, this interference manifests itself as conducted electrical interference and,
as such, is dealt with in other parts of the IEC 61000-4 standard series. Methods employed to
prevent effects from electromagnetic fields will normally also reduce the effects from these
sources.
The electromagnetic environment is determined by the strength of the electromagnetic field.
The field strength is not easily measured without sophisticated instrumentation nor is it easily
calculated by classical equations and formulas because of the effect of surrounding structures
or the proximity of other equipment that will distort and/or reflect the electromagnetic waves.
5 Test levels
The test levels are given in Table 1.
Table 1 – Test levels related to general purpose, digital radio telephones
and other RF emitting devices
Level Test field strength
V/m
1 1
2 3
3 10
4 30
x Special
NOTE x is an open test level and the associated field strength may
be any value. This level may be given in the product standard.

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This standard does not suggest that a single test level is applicable over the entire frequency
range. Product committees shall select the appropriate test level for each frequency range
needing to be tested as well as the frequency ranges. See Annex E for a guidance for product
committees on the selection of test levels.
The test field strength column gives values of the unmodulated carrier signal. For testing of
equipment, this carrier signal is 80 % amplitude modulated with a 1 kHz sine wave to simulate
actual threats (see Figure 1). Details of how the test is performed are given in Clause 8.
5.1 Test levels related to general purposes
The tests are normally performed without gaps in the frequency range 80 MHz to 1 000 MHz.
NOTE 1 Product committees may decide to choose a lower or higher transition frequency than 80 MHz between
IEC 61000-4-3 and IEC 61000-4-6 (see Annex G).
NOTE 2 Product committees may select alternative modulation schemes for equipment under test.
NOTE 3 IEC 61000-4-6 also defines test methods for establishing the immunity of electrical and electronic
equipment against radiated electromagnetic energy. It covers frequencies below 80 MHz.
5.2 Test levels related to the protection against RF emissions from digital radio
telephones and other RF emitting devices
The tests are normally performed in the frequency ranges 800 MHz to 960 MHz and 1,4 GHz
to 6,0 GHz.
The frequencies or frequency bands to be selected for the test are limited to those where
mobile radio telephones and other intentional RF emitting devices actually operate. It is not
intended that the test needs to be applied continuously over the entire frequency range from
1,4 GHz to 6 GHz. For those frequency bands used by mobile radio telephones and other
intentional RF emitting devices, specific test levels may be applied in the corresponding
frequency range of operation.
Also if the product is intended to conform only to the requirements of particular countries, the
measurement range 1,4 GHz to 6 GHz may be reduced to cover just the specific frequency
bands allocated to digital mobile telephones and other intentional RF emitting devices in
those countries. In this situation, the decision to test over reduced frequency ranges shall be
documented in the test report.
NOTE 1 Annex A contains an explanation regarding the decision to use sine wave modulation for tests related to
protection against RF emissions from digital radio telephones and other intentional RF emitting devices.
NOTE 2 Annex E contains guidance with regard to selecting test levels.
NOTE 3 The measurement ranges for Table 2 are the frequency bands generally allocated to digital radio
telephones (Annex G contains the list of frequencies known to be allocated to specific digital radio telephones at
the time of publication).
NOTE 4 The primary threat above 800 MHz is from radio telephone systems and other intentional RF emitting
devices with power levels similar to that of radio telephones. Other systems operating in this frequency range, e.g.
radio LANs operating at 2,4 GHz or higher frequencies, are generally very low power (typically lower than
100 mW), so they are much less likely to present significant problems.

61000-4-3 © IEC:200661000-4-3 ¤ IEC:2006 –– 25 13 – –
6 Test equipment
The following types of test equipment are recommended:
– Anechoic chamber: of a size adequate to maintain a uniform field of sufficient dimensions
with respect to the equipment under test (EUT). Additional absorbers may be used to
damp reflections in chambers which are not fully lined.
– EMI filters: care shall be taken to ensure that the filters introduce no additional resonance
effects on the connected lines.
– RF signal generator(s) capable of covering the frequency band of interest and of being
amplitude modulated by a 1 kHz sine wave with a modulation depth of 80%. They shall
have manual control (e.g., frequency, amplitude, modulation index) or, in the case of RF
synthesizers, they shall be programmable with frequency-dependent step sizes and dwell
times.
The use of low-pass or band-pass filters may be necessary to avoid problems caused by
harmonics.
– Power amplifiers: to amplify signal (unmodulated and modulated) and provide antenna
drive to the necessary field level. The harmonics generated by the power amplifier shall be
such that any measured field strength in the UFA at each harmonic frequency shall be at
least 6 dB below that of the fundamental frequency (see Annex D).
– Field generating antennas (see Annex B): biconical, log periodic, horn or any other linearly
polarized antenna system capable of satisfying frequency requirements.
– An isotropic field sensor with adequate immunity of any head amplifier and opto-
electronics to the field strength to be measured, and a fibre optic link to the indicator
outside the chamber. An adequately filtered signal link may also be used.
– Associated equipment to record the power levels necessary for the required field strength
and to control the generation of that level for testing.
Care shall be taken to ensure adequate immunity of the auxiliary equipment.
6.1 Description of the test facility
Because of the magnitude of the field strengths generated, the tests shall be made in a
shielded enclosure in order to comply with various national and international laws prohibiting
interference to radio communications. In addition, since most test equipment used to collect
data is sensitive to the local ambient electromagnetic field generated during the execution of
the immunity test, the shielded enclosure provides the necessary "barrier" between the EUT
and the required test instrumentation. Care shall be taken to ensure that the interconnection
wiring penetrating the shielded enclosure adequately attenuates the conducted and radiated
emission and preserves the integrity of the EUT signal and power responses.
The test facility typically consists of an absorber-lined shielded enclosure large enough to
accommodate the EUT whilst allowing adequate control over the field strengths. This includes
anechoic chambers or modified semi-anechoic chambers, an example of which is shown in
Figure 2. Associated shielded enclosures should accommodate the field generating and
monitoring equipment, and the equipment which exercises the EUT.
Anechoic chambers are less effective at lower frequencies. Particular care shall be taken to
ensure the uniformity of the generated field at the lower frequencies. Further guidance is
given in Annex C.
61000-4-3 ¤ IEC:2006 –– 27 14 – – 61000-4-3 © IEC:2006
6.2 Calibration of field
The purpose of field calibration is to ensure that the uniformity of the field over the test
sample is sufficient to ensure the validity of the test results. IEC 61000-4-3 uses the concept
of a uniform field area (UFA, see Figure 3), which is a hypothetical vertical plane of the field
in which variations are acceptably small. In a common procedure (field calibration), the
capability of the test facility and the test equipment to generate such a field is demonstrated.
At the same time, a database for setting the required field strength for the immunity test is
obtained. The field calibration is valid for all EUTs whose individual faces (including any
cabling) can be fully covered by the UFA.
The field calibration is performed with no EUT in place (see Figure 3). In this procedure, the
relationship between field strength within the UFA and forward power applied to the antenna
is determined. During the test, the required forward power is calculated from this relationship
and the target field strength. The calibration is valid as long as the test setup used for it
remains unchanged for testing, therefore the calibration setup (antenna, additional absorber,
cables, etc.) shall be recorded. It is important that the exact position, as much as is
reasonably possible, of the generating antennas and cables is documented. Since even small
displacements may significantly affect the field, the same positions shall be used also for the
immunity test.
It is intended that the full field calibration process should be carried out annually and when
changes have been made in the enclosure configuration (absorber replaced, area moved,
equipment changed, etc.). Before each batch of testing (see Clause 8), the validity of the
calibration shall be checked.
The transmitting antenna shall be placed at a distance sufficient to allow the UFA to fall within
the beam of the transmitted field. The field sensor shall be at least 1 m from the field
generating antenna. A distance of 3 m between the antenna and the UFA is preferred (see
Figure 3). This dimension is measured from the centre of a biconical antenna, or the front tip
of a log periodic or combination antenna, or from the front edge of horn or double ridge wave
guide antenna. The calibration record and the test report shall state the distance used.
Unless the EUT and its wires can be fully illuminated within a smaller surface, the size of the
UFA is at least 1,5 m × 1,5 m with its lower edge established at a height of 0,8 m above the
floor. The size of the UFA shall not be less than 0,5 m × 0,5 m. During the immunity test, the
EUT shall have the face to be illuminated coincident with this UFA (see Figures 5 and 6).
In order to establish the severity of the test for EUTs and cabling which must be tested close
to the floor (earth reference plane), the magnitude of the field is also recorded at 0,4 m
height. The obtained data is documented in the calibration record but is not considered for the
suitability of the test facility and for the calibration database.
Due to reflections at the floor in a semi-anechoic room, it is difficult to establish a UFA close
to an earth reference plane. Additional absorbing material on the earth reference plane may
solve this problem (see Figure 2).
The UFA is subdivided into a grid with a grid spacing of 0,5 m (see Figure 4 as an example of
an 1,5 m × 1,5 m UFA). At each frequency, a field is considered uniform if its magnitude
−0
measured at the grid points is within dB of the nominal value for not less than 75 % of all
+6
grid points (e.g. if at least 12 of the 16 points of an 1,5 m × 1,5 m UFA measured are within
the tolerance). For the minimum UFA of 0,5 m × 0,5 m, the field magnitude for all four grid
points shall lie within this tolerance.

61000-4-3 © IEC:200661000-4-3 ¤ IEC:2006 –– 29 15 – –
NOTE 1 At different frequencies, different measuring points may be within the tolerance.
−0
The tolerance has been expressed as dB to ensure that the field strength does not fall
+6
below nominal with an acceptable probability. The tolerance of 6 dB is considered to be the
minimum achievable in practical test facilities.
In the frequency range up to 1 GHz, a tolerance greater than +6 dB, up to +10 dB, but not
less than -0 dB is allowed for a maximum of 3 % of the test frequencies, provided that the
−0
actual tolerance is stated in the test report. In case of dispute, the dB tolerance takes
+6
precedence.
If the area intended to be occupied by the face of the actual EUT is larger than 1,5 m × 1,5 m
and an UFA with sufficient dimensions (preferred method) can not be realised, then the area
to be occupied by the EUT may be illuminated in a series of tests (“partial illumination”).
Either:
– a calibration shall be performed at different radiating antenna locations so that the
combined UFAs cover the area which will be occupied by the face of the EUT, and the
EUT shall then be tested with the antenna in each of these positions successively,
– or the EUT shall be moved to different positions so that each part of it falls within the UFA
during at least one of these tests.
NOTE 2 Each of the antenna positions requires a full field calibration.
Table 2 below demonstrates the concepts of full illumination and partial illumination as well as
where and how they can be applied.
Table 2 – Requirements for uniform field area for application of full illumination, partial
illumination and independent windows method
Frequency range Requirements of UFA size and Requirements of UFA size and calibration
calibration when the EUT fits when the EUT does not fit completely
completely within UFA (Full within UFA (Partial Illumination and
Illumination, the preferred method) Independent Windows, the alternative
methods)
Less than 1 GHz PARTIAL ILLUMINATION
Minimum UFA size 0,5 m × 0,5 m
UFA size in 0,5 m grid size steps (e.g., Minimum UFA size 1,5 m × 1,5 m
0,5 m × 0,5 m; 0,5 m × 1,0 m; 1,0 m ×
1,0 m; etc)
UFA size in 0,5 m grid size steps (e.g.,
1,5 m × 1,5 m; 1,5 m × 2,0 m; 2,0 m × 2,0 m;
Calibration in 0,5 m × 0,5 m grid steps
etc)
75 % of calibration points within
Calibration in 0,5 m × 0,5 m grid steps
specifications if UFA is larger than
0,5 m × 0,5 m. 100 % (all 4 points) must
75 % of calibration points within
be in specifications for 0,5 m × 0,5 m
specifications
UFA.
61000-4-3 ¤ IEC:2006 –– 31 16 – – 61000-4-3 © IEC:2006
Table 2 (continued)
Frequency range Requirements of UFA size and Requirements of UFA size and calibration
calibration when the EUT fits when the EUT does not fit completely
completely within UFA (Full within UFA (Partial Illumination and
Illumination, the
...