SIST EN IEC 61000-4-41:2025

SLOVENSKI STANDARD
01-marec-2025
Elektromagnetna združljivost (EMC) - 4-41. del: Preskusne in merilne tehnike -
Preskusi odpornosti proti širokopasovnemu sevanju
Electromagnetic compatibility (EMC) - Part 4-41: Testing and measurement techniques -
Broadband radiated immunity tests
Elektromagnetische Verträglichkeit (EMV) - Teil 4-41: Prüf- und Messverfahren -
Prüfungen der breitbandigen Störfestigkeit
Compatibilité électromagnétique (CEM) - Partie 4-41: Techniques d'essai et de mesure -
Essais d'immunité aux rayonnements à large bande
Ta slovenski standard je istoveten z: EN IEC 61000-4-41:2025
ICS:
33.100.20 Imunost Immunity
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 61000-4-41

NORME EUROPÉENNE
EUROPÄISCHE NORM January 2025
ICS 33.100.20
English Version
Electromagnetic compatibility (EMC) - Part 4-41: Testing and
measurement techniques - Broadband radiated immunity tests
(IEC 61000-4-41:2024)
Compatibilité électromagnétique (CEM) - Partie 4-41: Elektromagnetische Verträglichkeit (EMV) - Teil 4-41: Prüf-
Techniques d'essai et de mesure - Essais d'immunité aux und Messverfahren - Prüfungen der breitbandigen
rayonnements à large bande Störfestigkeit
(IEC 61000-4-41:2024) (IEC 61000-4-41:2024)
This European Standard was approved by CENELEC on 2024-12-27. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61000-4-41:2025 E

European foreword
The text of document 77B/892/FDIS, future edition 1 of IEC 61000-4-41, prepared by SC 77B "High
frequency phenomena" of IEC/TC 77 "Electromagnetic compatibility" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN IEC 61000-4-41:2025.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2026-01-31
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-01-31
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61000-4-41:2024 was approved by CENELEC as a
European Standard without any modification.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 61000-4-3 2020 Electromagnetic compatibility (EMC) - Part EN IEC 61000-4-3 2020
4-3 : Testing and measurement techniques
- Radiated, radio-frequency,
electromagnetic field immunity test

IEC 61000-4-41 ®
Edition 1.0 2024-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electromagnetic compatibility (EMC) –

Part 4-41: Testing and measurement techniques – Broadband radiated immunity

tests
Compatibilité électromagnétique (CEM) –

Partie 4-41: Techniques d'essai et de mesure – Essais d'immunité aux

rayonnements à large bande
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.100.20  ISBN 978-2-8327-0019-8

– 2 – IEC 61000-4-41:2024 © IEC 2024
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms . 10
4 General . 11
5 Test levels and test signal . 11
5.1 Test levels . 11
5.2 Test signal . 12
5.3 Frequency range and test signal bandwidth . 14
5.4 Spectrum mask . 15
5.5 Frequency stepping . 16
5.6 Selection of level . 17
6 Test equipment and level adjustment procedure . 17
6.1 Test instrumentation . 17
6.2 Description of the test facility . 18
6.3 UFA and validation of the spectrum shape . 18
6.3.1 General . 18
6.3.2 Saturation check and spectrum validation . 18
7 Test setup . 20
8 Test procedure . 20
8.1 Step size and test signal bandwidth . 20
8.2 Test signal and level setting . 20
9 Evaluation of the test results . 20
10 Test report . 21
Annex A (informative) Information on test signal generation . 22
A.1 General . 22
A.2 True noise generation . 22
A.3 Pseudo-random noise sequence . 23
Annex B (informative) Field generating antennas . 26
Annex C (informative) 4G and 5G signals . 27
C.1 Overview of the radio interface technology of 4G and 5G . 27
C.1.1 General . 27
C.1.2 Overview of the component RIT: E-UTRA/LTE . 27
C.1.3 Overview of the component RIT: NR . 30
C.2 Simulation of the 5G signal . 30
C.3 Application of a test model signal . 33
Annex D (informative) Guidelines for selecting test levels . 35
D.1 General . 35
D.2 Test levels related to general purposes . 36
D.3 Test levels related to the protection against RF emissions from 4G/5G
communications . 36
D.4 Guidelines to derive a test level from a field distribution . 39

IEC 61000-4-41:2024 © IEC 2024 – 3 –
Annex E (informative) Measurement uncertainty due to test instrumentation . 42
Annex F (informative) Test signal characterization . 43
F.1 General . 43
F.2 Test signal generation . 43
F.3 Definition of the crest factor . 43
F.4 Crest factor determination . 44
F.4.1 Mathematical determination for arbitrary waveform generator use . 44
F.4.2 Complementary cumulative distribution function (CCDF) . 44
F.5 Amplifier saturation . 45
F.6 Measurement methods . 46
F.6.1 General . 46
F.6.2 Spectrum analyser method . 46
F.6.3 Time domain measurement with a fast oscilloscope . 47
F.6.4 Power meter method . 48
F.7 Comparison of crest factor measurement results . 49
Bibliography . 50

Figure 1 – Example of the envelope of a 100 MHz wide test signal in frequency domain . 13
Figure 2 – Example of the envelope of a 100 MHz wide test signal in time domain . 13
Figure 3 – Pulse modulated test signal, with a period of 10 ms, and 50 % duty cycle . 14
Figure 4 – Spectrum mask of the broadband test signal at the output of the power

amplifier . 16
Figure A.1 – Principle of true noise generation . 22
Figure A.2 – Example of a 100 MHz wide band-limited true noise signal at a centre
frequency of 1 GHz . 22
Figure A.3 – Principle of band-limited broadband signal generation with an arbitrary
waveform generator . 23
Figure A.4 – Example signal spectrum of a band-limited pseudo random noise signal
(measured with 120 kHz bandwidth) . 24
Figure A.5 – Extract of the band-limited pseudo random noise signal in time domain
(measured with an oscilloscope) . 25
Figure A.6 – Extract of the signal spectrum of a band-limited pseudo random noise
signal (measured with 10 Hz bandwidth, normalized to 1 Hz bandwidth) . 25
Figure C.1 – Uplink/downlink time/frequency structure for FDD and TDD . 28
Figure C.2 – Uplink-downlink asymmetries supported by the E-UTRA/LTE RIT (TDD) . 29
Figure C.3 – Example of an OFDM spectrum . 31
Figure C.4 – Examples of a spectrum of the test signal in frequency domain . 32
Figure C.5 – Examples of a spectrum of the test signal in time domain . 32
Figure C.6 – Example of an equivalent power waveform and spectrum for NR-FR1-

TM1.1 . 34
Figure C.7 – Example of a channel power measurement for NR-FR1-TM1.1 . 34
Figure D.1 – Example of a channel power measurement on a 5G spectrum . 41
Figure F.1 – CCDF of a band-limited white gaussian noise signal . 45
Figure F.2 – CCDF of a band-limited white gaussian noise signal at the output of the
amplifier for different signal generator levels . 45
Figure F.3 – Test setup diagram for radiated immunity testing . 46

– 4 – IEC 61000-4-41:2024 © IEC 2024
Figure F.4 – Oscillogram of a 20 MHz wide gaussian noise signal with a centre
frequency of 700 MHz at the signal generator . 48

Table 1 – Test levels . 11
Table 2 – Pulse modulation of test signal . 12
Table 3 – Frequency ranges and test signal bandwidth . 14
Table 4 – Test signal requirements . 15
Table C.1 – Examples of the test model signal . 33
Table D.1 – Examples of test levels, associated protection distances – Mobile and

portable phones of 4G/5G communications . 37
Table D.2 – Examples of test levels, associated protection distances – Base stations of
4G/5G communications . 38
Table F.1 – Measurement of crest factors with different methods . 49

IEC 61000-4-41:2024 © IEC 2024 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 4-41: Testing and measurement techniques –
Broadband radiated immunity tests

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
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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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
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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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 61000-4-41 has been prepared by subcommittee 77B: High frequency phenomena, of IEC
technical committee 77: Electromagnetic compatibility. It is an International Standard.
It forms Part 4-41 of IEC 61000. It has the status of a basic EMC publication in accordance with
IEC Guide 107.
The text of this International Standard is based on the following documents:
Draft Report on voting
77B/892/FDIS 77B/895/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
– 6 – IEC 61000-4-41:2024 © IEC 2024
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 61000 series, published under the general title Electromagnetic
compatibility (EMC), can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document 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.

IEC 61000-4-41:2024 © IEC 2024 – 7 –
INTRODUCTION
IEC 61000 is published in separate parts 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: IEC 61000-6-1).
This part is an international standard which gives immunity requirements and test procedures
related to radiated disturbances generated by broadband signals.
Modern digital communication signals operate on multiple frequencies such as orthogonal
frequency division multiplexing (OFDM) and use bandwidths ranging from tens of MHz to
hundreds of MHz, all while employing in-band time division duplexing (TDD) or frequency
division duplexing (FDD) transmission technology, or both. Such broadband signals can cause
a performance degradation or malfunction of other equipment, or both. In this document, the
disturbance is not a frequency sweep of a narrowband signal but a broadband signal with
coexisting multiple frequencies which is stepped through the desired frequency range.
Examples of broadband signals are LTE signals and 5G mobile communication signals.

– 8 – IEC 61000-4-41:2024 © IEC 2024
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 4-41: Testing and measurement techniques –
Broadband radiated immunity tests

1 Scope
This part of IEC 61000 relates to broadband radiated disturbances generated by, for example,
communication devices or services, transmitters or industrial electromagnetic sources or any
other devices capable of generating such a signal.
The object of this document is to establish a common reference for evaluating the immunity of
electrical and electronic equipment when subjected to broadband radiated electromagnetic
fields.
This document specifies testing in the frequency ranges above 80 MHz, limited only by the
capabilities of commercially available test instrumentation.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61000-4-3:2020, Electromagnetic compatibility (EMC) – Part 4-3: Testing and
measurement techniques – Radiated, radio-frequency, electromagnetic field immunity test
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61000-4-3 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
auxiliary equipment
AE
equipment necessary to provide the equipment under test (EUT) with the signals required for
normal operation and equipment to verify the performance of the EUT
3.1.2
equivalent carrier electric field strength
electric field strength at carrier frequency equivalent to the square root of the cumulative electric
field power (E ) caused by the radiation of broadband signal
Note 1 to entry: Equivalent carrier electric field strength is expressed in V/m.

IEC 61000-4-41:2024 © IEC 2024 – 9 –
3.1.3
broadband signal
signal where the energy is distributed over several megahertz, either by the broadband nature
of the signal itself or by a modulation, for example by a collection of subcarriers
Note 1 to entry: In typical applications a broadband signal can be as wide as 5 MHz to 100 MHz.
3.1.4
duty cycle
fraction of the period where a repetitive signal is above a specified threshold
Note 1 to entry: That period is the duration of time for one cycle of a repeating event. It is the reciprocal of repetition
frequency.
3.1.5
test generator
generator capable of generating the required test signal
Note 1 to entry: The test generator can, for example, include a vector signal generator, modulation sources,
attenuators, broadband power amplifiers and filters, etc. See Annex A for additional information on test generator.
3.1.6
white noise
random noise which has a continuous spectrum and a constant power spectral density in the
frequency band considered
[SOURCE: IEC 60050-702:1992, 702-08-39, modified – In the term “flat random noise” has
been removed.]
3.1.7
electric field spectral density
quantity derived from the electric power spectral density (PSD) of a broadband signal
Note 1 to entry: Further information can be found in Annex D.
Note 2 to entry: For electric field spectral density, the unit is (V/m)/ Hz .
3.1.8
power spectral density
PSD
distribution as a function of frequency of the power per unit bandwidth of the spectral
components of a signal or a noise having a continuous spectrum and a finite mean power
Note 1 to entry: A PSD is the measure of signal's power content versus frequency. A PSD is typically used to
characterize broadband signals. The amplitude of the PSD is normalized by the spectral resolution employed to
measure the signal.
[SOURCE: IEC 60050-713:1998, 713-09-12, modified – In the term “power spectrum density”
has been removed and Note 1 has been added.]
3.1.9
crest factor
ratio between peak amplitude (envelope) and RMS value, usually expressed in dB

– 10 – IEC 61000-4-41:2024 © IEC 2024
3.2 Abbreviated terms
ACLR adjacent channel leakage power ratio
AE auxiliary equipment
AWG arbitrary waveform generator
BPSK binary phase shift keying
BS base station
BW bandwidth
CA carrier aggregation
CCDF complementary cumulative distribution function
CW continuous wave
DFTS-OFDM discrete Fourier transform spread-OFDM
DL downlink
eMBB enhanced Mobile BroadBand
eMTC enhanced MachineType Communication
eNB evolved Node B
EUT equipment under test
E-UTRA Evolved-Universal mobile telecommunication system Terrestrial Radio
Access
EVM error vector magnitude
FDD frequency division duplexing
GP Guard Period
IMT International Mobile Telecommunications
LTE Long-Term Evolution
mMTC massive Machine Type Communication
NB-IoT narrow band-Internet of Things
NR New Radio
OFDM orthogonal frequency division multiplexing
PAPR peak-to-average power ratio
PM pulse modulation
PSD power spectral density
QAM quadrature amplitude modulation
QPSK quadrature phase shift keying
RB resource block
RF radio frequency
RIT radio interface technology
SEM spectral emission mask
TDD time division duplexing
TTI transmission time interval
UE user equipment
UFA uniform field area
UL uplink
URLLC Ultra Reliable Low Latency Communication
WGN white gaussian noise
IEC 61000-4-41:2024 © IEC 2024 – 11 –
rd
3GPP 3 Generation Partnership Project
4 General
The source of disturbance covered by this document is an electromagnetic field, consisting of
broadband signals, generated by, for example, communication devices or services, transmitters
or industrial electromagnetic sources or any other devices capable of generating such a signal.
The frequency range covered by this document is specified in Table 3.
5 Test levels and test signal
5.1 Test levels
The test levels are given in terms of an equivalent carrier electric field strength consistent with
the level-setting process and the electric field spectral density spread out to the test signal
bandwidth.
The levels in columns 3 to 6 of Table 1 show the electric field spectral density derived from the
power spectral density of the broadband test signal assuming that the different spectrum
components are uncorrelated.
The test level is derived from the uniform field area (UFA) level-setting process. The signal
power to generate the test levels of Table 1 should be equal to the total power of the broadband
signal.
Table 1 – Test levels
Test level Equivalent Electric field spectral density
carrier electric
 µV 
field strength
dB
 
m⋅ Hz
 
V/m
BW = 5 MHz BW = 20 MHz BW = 40 MHz BW = 100 MHz
1 1 53,0 47,0 44,0 40,0
2 3 62,5 56,5 53,5 49,5
3 10 73,0 67,0 64,0 60,0
4 30 82,5 76,5 73,5 69,5
NOTE 5 MHz and 40 MHz bandwidth (BW) are indicated for the convenience of the product committee.

This document does not suggest that a single test level is applicable over the entire frequency
range. The product committees shall select the frequency range(s) to be tested as well as the
appropriate test level(s). Annex D provides guidance for product committees on the selection
of test levels.
Product committees may use test levels other than those listed in Table 1. However, once the
equivalent carrier electric field strength is determined, the test levels for each bandwidth follow
the relationship between the test levels in Table 1.

– 12 – IEC 61000-4-41:2024 © IEC 2024
5.2 Test signal
Real broadband communication signals are largely based on orthogonal frequency division
multiplexing (OFDM). The parameters (number of carriers, modulation per carrier, etc.) are so
diverse that an internationally agreed set of parameters that is representative of all conceivable
broadband communication services does not seem to make sense. In accordance with the
nature of the interference, a band-limited noise is therefore specified as the test signal. The
signal can be generated by a physical noise generator with a filter or by an arbitrary waveform
generator, which periodically plays a pseudo-random code. With the latter, care shall be taken
that the sequence is long enough to produce a spectrum that is as continuous as possible.
An additional important parameter of the test signal is the crest factor. The crest factor of the
signal generator output signal shall be at least 10 dB. Information on test signal characterization
is given in Annex F.
NOTE 1 The higher the crest factor, the higher the demands on the dynamic reserves of the power amplifier.
The broadband signals used as test signals in this document are time variant to simulate
changes in amplitude due to time division transmission scheme. For testing purposes, a pulse
modulation is selected. A 50 % duty cycle is preferred. The modulation is specified in Table 2.
Product committees may select other duty cycles if specific transmission signals are supposed
to be emulated by test signals.
Table 2 – Pulse modulation of test signal
Parameter Value
Modulation frequency 100 Hz ± 10 Hz
Rise/fall time of the envelope < 20 µs
(between 10 % and 90 % of amplitude)
Duty cycle (50 ± 2) %
Figure 1 and Figure 2 show an example of a test signal with a bandwidth of 100 MHz in the
frequency domain and time domain, respectively.

IEC 61000-4-41:2024 © IEC 2024 – 13 –

Figure 1 – Example of the envelope of a 100 MHz wide test signal in frequency domain

Figure 2 – Example of the envelope of a 100 MHz wide test signal in time domain
The characteristics of a modulated test signal are shown in Figure 3. Note that when the pulse
modulation is activated, the energy of the test signal is reduced to 50 % (-3 dB) because the
amplitude is close to zero while the signal is “OFF”. The test amplitude during the “ON” period
should however remain unchanged at the level derived from the UFA level-setting process.

– 14 – IEC 61000-4-41:2024 © IEC 2024

Figure 3 – Pulse modulated test signal, with a period of 10 ms, and 50 % duty cycle
5.3 Frequency range and test signal bandwidth
The test signals for this broadband immunity test standard are selected as being representative
of modern digital radio communication signals in the sense that the signals contain electrical
energy which is distributed over several megahertz.
The test signal used in this document does not contain any information but is considered as
white noise having equal spectral density at all frequencies within the test signal bandwidth.
The test signal bandwidth is specified in Table 3.
Table 3 – Frequency ranges and test signal bandwidth
Start frequency Stop frequency Test signal bandwidth
MHz MHz MHz
80 600 Under consideration
600 1 800 20
1 800 6 000 100
6 000 Upper frequency limit Under consideration

This document specifies testing in the frequency ranges above 80 MHz, limited only by the
capabilities of commercially available test instrumentation.
Product committees may specify frequency ranges (above 80 MHz) and test signal bandwidth
other than those listed in Table 3.

IEC 61000-4-41:2024 © IEC 2024 – 15 –
5.4 Spectrum mask
The test signal shall have the spectral properties as specified in Figure 4 and Table 4, which
shall be verified at the output of the power amplifier.
The spectral density is measured using a receiver bandwidth of 1 MHz and an RMS detector. If
a spectrum analyser is used for the measurement, the resolution bandwidth shall be set to
1 MHz and the video bandwidth shall be set to at least 3 MHz.
The test signal generator shall generate the signal in such a manner that the total RF power
without the pulse modulation of the signal (often referred to as the channel power) is equal to
the output power when the test generator is set to unmodulated sine wave signal (continuous
wave (CW) signal). This will usually be the case for signal generators.
Table 4 – Test signal requirements
Test signal bandwidth a b c d
MHz MHz dB dB dB
5 10 20 6 3
20 10 20 6 3
40 20 20 6 3
100 20 20 6 3
For specification of a, b, c and d, see Figure 4.
The value for a at test signal bandwidth of 5 MHz was specified due to frequency response of the signal generating
equipment.
The upper amplitude limit decays linearly by b dB versus frequency within a MHz of upper and lower band edges.
The lower amplitude limit decays linearly by d dB versus frequency within 500 kHz of upper and lower band edges.
NOTE 5 MHz and 40 MHz test signal bandwidth are indicated for the convenience of product committees.

– 16 – IEC 61000-4-41:2024 © IEC 2024

Key
Red line upper limit
Blue line example test signal
Green line lower limit
NOTE See also Annex A.
Figure 4 – Spectrum mask of the broadband test signal
at the output of the power amplifier
5.5 Frequency stepping
The test signal is scanned using step sizes determined by the test signal bandwidth as specified
below. The intention is that the test signal shall be applied seamlessly over the entire frequency
range in steps of the selected test signal bandwidth.
The start of the frequency stepping shall be performed as specified below. If the specified
frequency range does not match the full steps of the test signal bandwidth, then the test signal
can exceed beyond the highest test frequency.
Examples of frequency stepping are found below:
1) First test frequency f is selected so it is half the test signal bandwidth above the start
frequency.
Example1: Using a 20 MHz test signal bandwidth and starting test at 600 MHz, the first
centre frequency setting is 600 MHz + ½ times 20 MHz = 610 MHz.
Example 2: Using a 100 MHz test signal bandwidth and starting test at 1 800 MHz, the first
frequency setting is 1 800 MHz + ½ times 100 MHz = 1 850 MHz.
2) Next test frequency f is selected so it is one test signal bandwidth above f .
2 1
Example 1: Using a 20 MHz test signal bandwidth, f = 610 MHz + 20 MHz = 630 MHz.
Example 2: Using a 100 MHz test signal bandwidth, f = 1 850 MHz + 100 MHz = 1 950 MHz.
IEC 61000-4-41:2024 © IEC 2024 – 17 –
3) The steps are repeated until the stop frequency is covered by the bandwidth of a test signal.
Example 1: 60 steps are necessary to cover the frequency range 600 MHz to 1 800 MHz
using a 20 MHz test signal bandwidth. The last test frequency is 1 790 MHz.
Example 2: 42 steps are necessary to cover the frequency range 1 800 MHz to 6 000 MHz
using a 100 MHz test signal bandwidth. The last test frequency is 5 950 MHz.
5.6 Selection of level
The test level is set as the signal power at each test frequency. The testing according to this
document is based upon the level-setting process executed for testing with modulated sine
wave signals, as specified in IEC 61000-4-3.
If level-setting data are already available for the UFA in the test laboratory, such data are
preferred, and can be directly applied for the present testing. Data recorded for testing in
accordance with IEC 61000-4-3 are often available at steps of 1 % of the preceding frequency,
starting at 80 MHz.
The level-setting data for the centre frequency of the broadband test signal should be chosen
from the two neighbouring IEC 61000-4-3 level-setting frequencies by interpolation.
If several IEC 61000-4-3 level-setting frequencies are available within one test signal bandwidth,
it is sufficient to select the nearest IEC 61000-4-3 frequency for level setting. For example,
when testing with a 20 MHz test signal bandwidth and starting at 600 MHz (600 MHz to
620 MHz), several IEC 61000-4-3 level-setting frequencies are available (603,016 MHz,
609,046 MHz, 615,137 MHz). The frequency closest to the centre of the test signal is selected
for level setting (609,046 MHz in this example).
It is, however, also allowed to do an individual UFA level-setting process using the highest level
intended for testing (see Table 1), step sizes of 20 MHz or 100 MHz (if not otherwise specified
by a product committee) and covering the centre frequencies of the test signals selected for
testing.
As the test generator provides the same total RF power for an unmodulated sine wave signal
(CW-signal) and for the test signal bandwidth (see 5.4), the test level can be monitored and if
necessary adjusted by measuring the unmodulated output signal from the power amplifier using
a power meter, which is capable of measuring both CW signals and broadband signals.
6 Test equipment and level adjustment procedure
6.1 Test instrumentation
Test equipment and level adjustment procedures adopted for this document are similar to those
specified in IEC 61000-4-3, with minor modifications due to the nature of the test signal:
– Anechoic chamber: of a size adequate to maintain a uniform field of sufficient dimensions
with respect to the equipment under test (EUT).
– RF signal generator(s): capable of covering the frequency band of interest and as a minimum
being capable of generating the test signal as specified in Clause 5. It can either be
equipped with a band-limited white noise generator or an arbitrary waveform generator. In
addition, pulse modulation is required either in hardware or as part of the waveform file for
the arbitrary waveform generator. For the setting of the test level, it shall be able to adjust
the signal amplitude of the broadband signal to a desired channel power (total power).
– EMI filters: if used, the filters shall introduce no additional resonan
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