CISPR TR 16-4-5:2006/AMD2:2021

Amendment 2 - Specification for radio disturbance and immunity measuring apparatus and methods - Part 4-5: Uncertainties, statistics and limit modelling - Conditions for the use of alternative test methods

General Information

• Status: Published
• Publication Date: 28-Oct-2021
• ICS: 33.100.10 - Emission
• ICS: 33.100.20 - Immunity
• Technical Committee: CIS/A - Radio-interference measurements and statistical methods
• Drafting Committee: JWG-A/H - CISPR/CIS/A/JWG JWG-A/H
• Current Stage: PPUB - Publication issued
• Start Date: 14-Jun-2021
• Completion Date: 29-Oct-2021

Relations

• Amends: CISPR TR 16-4-5:2006 - Specification for radio disturbance and immunity measuring apparatus and methods - Part 4-5: Uncertainties, statistics and limit modelling - Conditions for the use of alternative test methods
• Effective Date: 05-Sep-2023

Standards Content (Sample)

CISPR TR 16-4-5
®

Edition 1.0 2021-10
TECHNICAL
REPORT

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inside

INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE

AMENDMENT 2
Specification for radio disturbance and immunity measuring apparatus and
methods –
Part 4-5: Uncertainties, statistics and limit modelling – Conditions for the use of
alternative test methods

CISPR TR 16-4-5:2006-10/AMD2:2021-10(en)

---------------------- Page: 1 ----------------------
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CISPR TR 16-4-5

®


Edition 1.0 2021-10




TECHNICAL



REPORT








colour

inside




INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE





AMENDMENT 2



Specification for radio disturbance and immunity measuring apparatus and

methods –

Part 4-5: Uncertainties, statistics and limit modelling – Conditions for the use of

alternative test methods





















INTERNATIONAL

ELECTROTECHNICAL

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ICS 33.100.10; 33.100.20 ISBN 978-2-8322-9844-2




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– 2 – CISPR TR 16-4-5:2006/AMD2:2021
 IEC 2021
FOREWORD
This amendment has been prepared by subcommittee CISPR A: Radio-interference measure-
ments and statistical methods, of IEC technical committee CISPR: International special com-
mittee on radio interference.
The text of this amendment is based on the following documents:
DTR Report on voting
CIS/A/1321/DTR CIS/A/1324/RVDTR

Full information on the voting for the approval of this amendment can be found in the report on
voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC website under "http://web-
store.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.

_____________

1 Scope
Add, in the second sentence, the following new text “and total radiated power” to the
parentheses to read: “i.e. field strength and total radiated power”.
2 Normative references
Add the following new reference to the existing list:
CISPR 16-1-1:2019, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1-1: Radio disturbance and immunity measuring apparatus – Measuring appa-
ratus
Delete the existing reference to CISPR 16-4-1, modified by Amendment 1.
Replace the existing reference to CISPR 16-4-2:2003 with the following:

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CISPR TR 16-4-5:2006/AMD2:2021 – 3 –
 IEC 2021
CISPR 16-4-2:2011, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 4-2: Uncertainties, statistics and limit modelling – Measurement instrumentation
uncertainty
CISPR 16-4-2:2011/AMD1:2014
CISPR 16-4-2:2011/AMD2:2018
3 Terms and definitions
3.8
intrinsic uncertainty of the measurand
Replace the existing source, modified by Amendment 1, with the following: “[CISPR 16-4-
1:2009, 3.1.6, modified – Deletion of notes]”
Add, after the existing definition 3.10, added by Amendment 1, the following new term and
definition as follows:
3.11
EUT volume
cylinder defined by EUT boundary diameter and height that fully encompasses all portions of
the actual EUT, including cable racks and 1,6 m of cable length (for 30 MHz to 1 GHz), or 0,3 m
of cable length (for 1 GHz and above)
NOTE 1 The test volume is one of several criteria limiting the EUT volume.
NOTE 2 The EUT volume has a diameter D (boundary diameter) and a height h.
4 Symbols and abbreviated terms
Add, to the existing introductory statement, the following new sentence as follows:
The following abbreviations are used in this technical report. Note that the symbol k is used for
four different quantities.
Add the following new lines to the existing list modified by Amendment 1:
FAR fully anechoic room
RC reverberation chamber
SCU standards compliance uncertainty
Replace the two existing lines K and k with the following:
k = 2π/λ, wave number (in this document, k is used in the electrical size ka, where a is the
EUT radius)
k(f) linear conversion factor
K(f) logarithmic conversion factor
k coverage factor
k Boltzmann’s constant

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– 4 – CISPR TR 16-4-5:2006/AMD2:2021
 IEC 2021
5 Introduction
Replace the existing text with the following new text:
Over the years, several test methods and test set-ups for radiated disturbance measurement
have been described in basic standards. One particular combination of test method and test
set-up also having defined disturbance limits is the open area test site (OATS) method, which
has proven to be successful for the protection of radio services. Since the first edition of this
document, limits have been defined for other – alternative – test methods, e.g., fully anechoic
rooms and TEM waveguides, but not for reverberation chambers.
Each alternative method can be used to get measurement results related to disturbance from
an EUT. Although each method gives a disturbance level from an EUT, the different methods
might capture the EUT disturbance differently. For example, considering radiated disturbance
measurements, different methods may capture different EUT radiation pattern lobes, a different
number of lobes, or the test facility might alter the EUT radiation pattern producing a different
apparent disturbance level. Therefore the limits defined for the established test method cannot
be applied directly to the alternative test methods. Consequently, procedures are needed to
derive limits to be used for the results of alternative test methods.
The specification of such procedures considers the general goal of disturbance measurements,
which is to verify whether an EUT satisfies or violates certain compliance criteria. Past experi-
ence has shown that using the present system of established test methods and associated limits
yields a situation without many cases of interference due to conducted disturbance or radiated
disturbance. Applying an established test method with its associated limits will fulfill the protec-
tion requirement with a high probability. To preserve this situation, the most important require-
ment for the use of alternative test methods is the following:
– Use of an alternative test method in a normative standard shall provide the same protection
of radio services as the established test method.
This requirement can be met by developing procedures to derive disturbance limits for alterna-
tive test methods from the existing limits of the established test methods. Such procedures shall
relate the results from an alternative test method to those from an established test method.
Using the relations derived in this document, the limits of the relevant established test method
can be converted into limits for the alternative test method. The measured values of the alter-
native test method can then easily be evaluated against the converted limits. Such procedures
will provide a similar amount of protection, even though an alternative test method is used.
The limit conversion procedures consider the preceding goal of disturbance measurements.
The results of standard disturbance measurements can be considered as an approximation of
the interference potential of an EUT. Depending on the characteristics of an EUT (e.g., radiation
pattern characteristics for radiated disturbance test methods), and the test set-up, the measured
value deviates from the actual interference potential of the EUT. This deviation can be divided
into two parts: 1) a systematic deviation, which can be interpreted as a bias of the test method;
and 2) a random deviation depending on the characteristics of different EUTs, which can be
interpreted as an uncertainty of the test method. Each disturbance test method contains both
quantities, and consequently the established test method does too. In the following clauses, a
procedure based on these two quantities for comparing an alternative test method with the
established test method is described. To determine these quantities, the abstract term “inter-
ference potential” shall be expressed in terms of a physical quantity. For the purposes of this
document, this physical quantity is called the “reference quantity” X. Other details about com-
1
parison of test methods using a reference quantity can be found in [1] .
__________
1
 Figures in square brackets refer to the Bibliography.

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CISPR TR 16-4-5:2006/AMD2:2021 – 5 –
 IEC 2021
The significance of a reference quantity is under discussion (see Magdowski [16]). It is not used
in the derivation of limits for an alternative test method based on measurements (see Clause 7
of CISPR TR 16-4-5:2006/AMD1:2014), and in the derivation of limits for disturbance measure-
ments using a reverberation chamber (i.e. in this document).
Figure 1 – Overview of quantities to estimate for use in conversion procedure
Replace the existing figure with the following:

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– 6 – CISPR TR 16-4-5:2006/AMD2:2021
 IEC 2021
Figure 2 – Overview of limit conversion procedure using estimated quantities
Replace the existing figure with the following:


Table 2 ‒ Overview of quantities and defining equations for conversion process
Add, at the bottom of the existing table, modified by Amendment 1, the following new rows:
E Maximum field strength of an EUT in µV/m measured using the ETM, (35)
max
i.e. at d = 10 m at an OATS/SAC from 80 MHz to 1 000 MHz,
and at d = 3 m at a FSOATS/FAR from 1 GHz to 18 GHz
P Power transmitted from an EUT in pW measured using the reverberation chamber (35)
T
a)
test method (ATM), and virtual power producing the field-strength maximum E
max
measured using the ETM
a)
 The virtual power is the power generating E assuming the EUT directivity is estimated in this document.
max

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CISPR TR 16-4-5:2006/AMD2:2021 – 7 –
 IEC 2021
Add, after the existing Clause 7, modified by Amendment 1, the following new Clause 8:
8 Derivation of limits for the use of reverberation chambers as ATM for
radiated disturbance measurements based on a statistical analysis of all
essential factors
8.1 Conversion factor
Measurement of radiated power from an EUT using the RC method is described in
IEC 61000-4-21 [22]. This clause attempts to provide rules to derive disturbance limits for the
radiated power measured using the RC test method based on existing limits for radiated field
strength measured using the ETM. Radiated field strength and radiated power of an EUT are
related via the EUT directivity, and EUT directivity depends on frequency and EUT volume.
Because the type of an EUT and its directivity are typically unknown for generic and product
standards, this clause uses a statistical estimate based on assumptions described by Krauthäu-
ser [19]. For comparison and easier understanding, the conversion factors using a short dipole
as a model are described in D.2.
With reference to Annex D, conversion factors
– from OATS/SAC to RC for 80 MHz to 1 000 MHz, and
– from FSOATS/FAR to RC for 1 GHz to 40 GHz.
are introduced.
NOTE The start frequency of 80 MHz is selected because IEC 61000-4-21:2011, Table B.2 [22] on field uniformity
requirements starts at 80 MHz. Because there are RCs with lower or higher lowest useable frequencies (LUFs),
80 MHz can be replaced by “LUF.” The highest frequency of 40 GHz is selected because that is under consideration
to be the highest frequency for all CISPR documents pending agreement by NCs.
The linear conversion factor k(f) is defined as in Equation (35)
2

kf( )= E P (35)
max T

where
E is the maximum field strength of an EUT in µV/m measured using the ETM;
max
P is the power transmitted from an EUT in pW measured using the RC test method.
T
2 2 2
The unit of k(f) is V /m W or Ω/m . To convert into logarithmic quantities, Equation (35) can be
written as Equation (36):
2
lgP lgE− lgkf , or
( )
T max
(36)
10lgP 20lgE−10lgkf
( )
T max


The logarithmic conversion factor K(f) is defined as in Equation (37):
K f = 10lgkf
( ) ( ) (37)


=
=

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– 8 – CISPR TR 16-4-5:2006/AMD2:2021
 IEC 2021
The logarithmic conversion factor can be used to convert radiated disturbance limits L in
ETM
dB(µV/m) into limits of the disturbance power L in dB(pW) measured in an RC as shown in
ATM
Equation (38) (see also Equation (15) in 6.10).
L dB pW L dB μV/m− Kf
( ) ( ) ( ) (38)
ATM ETM


2
The logarithmic conversion factor K(f) has the unit dB(Ω/m ).
8.2 Measurement uncertainty
Equation (7) and Equation (9) of 6.7 provide the combined standard uncertainties of ATM and
ETM results with contributions designated in subscripts as: “m” for the instrumentation uncer-
tainty, “intrinsic” for the intrinsic uncertainty of the measurand, and “inherent” for the inherent
uncertainty of the method.
22 2
u=uu++ u

XTM XTM,m XTM,intrinsic XTM,inherent
where X in the subscript terms denotes either E or A (i.e. ETM or ATM).
For the effect of the measurement uncertainties of ETM and ATM on the disturbance limit, the
expanded uncertainties are compared (see Equation (16) in 6.10). The expanded uncertainty
of the conversion factor in Annex D (2σ in Table D.2, Table D.3,Table D.4,Table D.6, Table D.7
and Table D.8) takes into account the inherent uncertainties of the ETM (U ) and ATM
inherent,ETM
(U ). The inherent uncertainty is an indicator of the ability of a measurement proce-
inherent,ATM
dure to account for differences in EUT characteristics. A three-dimensional (3D) spatial scan
would provide the lowest uncertainty for capturing the maximum field strength radiated by an
EUT, but none of the ETMs are ideal in that respect. However, the RC ATM does capture the
radiated power of an EUT across all directions. Consequently, the inherent uncertainty of the
RC ATM is zero whereas the inherent uncertainties of the ETMs are non-zero.
In addition to the uncertainty of the conversion factor, the actual EUT size can deviate from the
EUT size assumed for the conversion factor calculation in Annex D, which justifies a contribution
U .
EUT
As can be seen from Table H.1 of CISPR TR 16-4-1:2009, the SCU U of the ETM
ETM,SC
(OATS/SAC with d = 10 m) is on the order of 10 dB, whereas U is around 5 dB according
XTM,m
to CISPR 16-4-2. Thus,
22
UU + U
ETM,SC ETM,intrinsic ETM,m
and consequently
22
U UU−= 8,7 dB
ETM,intrinsic ETM,SC ETM,m
This means that the intrinsic uncertainty of the ETM is much larger than the uncertainty of the
conversion factor K, so Equation (28) of 7.2.3 does not apply for Annex D. The intrinsic uncer-
tainty is largely dependent on cable layout and cable termination, which is an important topic
for the reproducibility of measurement set-ups. By future standardization of cable layout and
cable termination, intrinsic uncertainty and standards compliance uncertainty can be minimized.
=
=
=

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CISPR TR 16-4-5:2006/AMD2:2021 – 9 –
 IEC 2021
At present values of SCU (and intrinsic uncertainty) are not available for the ETM above 1 GHz,
as well as for the RC ATM below and above 1 GHz. This does not mean that the RC method
should be precluded for radiated disturbance measurements usage; there is no reason to as-
sume that the SCU of the RC method results will be larger than the SCU of the ETM results.
Product committees should provide appropriate investigations and measurements for establish-
ing the SCU.
In addition to any deviation from the EUT size for the conversion factor, the EUT type can be
different from that assumed for the conversion; e.g. with different cable arrangement and cable
termination. This means that Equation (32), Equation (33), and Equation (34) of 7.2.3 also apply
for the use of an RC disturbance measurement method as an ATM.
Details on instrumentation contributions to uncertainty for RC disturbance measurement results
is given in D.4.
B.1.1.5 Estimate the standard uncertainties of the test methods (see 6.6)
Replace the existing first paragraph with the following new paragraph:
Instrumentation uncertainty: At the time of drafting of this Annex, for the alternative test
method (3 m FAR), the instrumentation uncertainty had not yet been given in CISPR standards.
For the antenna and site contributions, numeric values from the final technical report of the EU
FAR project have been used [4]. The other numeric values were taken from CISPR 16-4-2:2003
[24], because these were expected to be the same for OATS and FAR. These instrumentation
measurement uncertainties are given in Table B.1. For the established test method, the meas-
urement instrumentation uncertainty is as shown in the basic standard CISPR 16-4-2:2011.
B.2.1.5 Estimate the standard uncertainties of the test methods (see 6.6)
Replace, in the first paragraph, "CISPR 16-4-2:2003" with " CISPR 16-4-2:2011".
B.2.1.8 Verify the calculated values (see 6.9)
Replace, in the last paragraph, "CISPR 16-4-2:2002" with " CISPR 16-4-2:2011".

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– 10 – CISPR TR 16-4-5:2006/AMD2:2021
 IEC 2021
Add, at the end of the existing Annex C, added by Amendment 1, the following new Annex D:
Annex D
(informative)

Statistical method for conversion of disturbance limits from radiated
disturbance established test methods to the RC test method
D.1 General
Radiated disturbance established test methods (ETMs) measure field strength at a specified
distance from an EUT, whereas the RC test method (alternative test method, ATM) measures
the radiated power from an EUT. Because the EUT directivity varies from type to type, statistical
techniques are used to derive conversion factors from ETM results to ATM results. With in-
creasing electrical size of an EUT, the complexity of an EUT’s radiation pattern increases
(see Wilson [17]).
Wilson [17] explains how the electrical size of an EUT is established by the quantity ka, where
k = 2π/λ is the wave number, and a is the radius of the minimum sphere that encloses the EUT.
The preceding concept applies for this entire annex. An EUT is considered electrically large, if
ka > 1, and it is electrically small, if ka ≤ 1. Figure D.1 shows an example radiation pattern for
a simulated electrically-large emitter. Table D.1 provides the EUT dimensions for the transition
from electrically small to electrically large as a function of frequency.
Wilson [17] also provides a statistical estimate of 3 dB for the probability of finding the maximum
radiation between a planar-cut scan (e.g. an EUT rotation without an antenna height scan) and
a full-sphere scan valid for very large EUTs. Thus, the planar-cut scan is regarded as a reduced
sampling procedure for finding the maximum field strength of an EUT. This also means that the
radiation limit for a full-sphere scan of a large EUT can be reduced by a conservative amount
of 3 dB if the full-sphere scan is replaced by a planar-cut scan.

NOTE The Y-plane and Z-plane patterns have similar characteristics, but normally only a single lobe in one plane
reaches the maximum (i.e. amplitude of 25 in this example).
Figure D.1 – Simulated radiation pattern of an electrically large emitter
(50 cm radius, ka = 10,5 at 1 GHz) in a single plane (X-plane) (Wilson [17])

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CISPR TR 16-4-5:2006/AMD2:2021 – 11 –
 IEC 2021
Table D.1 – Overview of EUT diameters (= 2a) at the transition
from electrically small to electrically large (from [17])
Frequency k ka radius a diameter
MHz 1/m cm cm
30 0,6 1,0 159,2 318,3
100 2,1 1,0 47,8 95,5
200 4,2 1,0 23,9 47,7
500 10,5 1,0 9,6 19,1
1 000 20,9 1,0 4,8 9,6
2 000 41,9 1,0 2,4 4,8
5 000 104,7 1,0 0,9 1,9
10 000 209,4 1,0 0,5 1,0
20 000 418,9 1,0 0,2 0,5
40 000 837,8 1,0 0,1 0,2

D.2 Models for EUT directivity
For a starting point Annex H of IEC 61000-4-20:20— [18] uses a Hertzian, i.e. short, dipole
(D = 3/2, and D is directivity) as a model for an EUT. For the Hertzian dipole in free space
max
(at an FSOATS/FAR) the linear conversion factor k can be calculated using Equation (D.1):
3 η
2
0
E = P
max T
2
2
4πd
2
E 3 η
max 0

k (D.1)
2
P 2
4πd
T

where
η is the free space wave impedance (approximately 120π Ω);
0
d is the measurement distance.
2 2
For d = 3 m, k = 5 V /(m W).
For a Hertzian dipole in half space (at an OATS/SAC) a geometry factor g is included, taking
max
into account the reflection from the ground plane, per Equation (D.2):
3 η
22
0
E = gP
max max T
2
2
4πd
2
E η
3
max 0 2

kg (D.2)
max
2
P 2
4πd
T

2 2
For d = 10 m and g ≈ 2, k = 1,8 V /(m W).
max
==
==

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– 12 – CISPR TR 16-4-5:2006/AMD2:2021
 IEC 2021
For the Hertzian dipole model, the conversion factor is independent of frequency. Using Equa-
tion (36) (see 8.1) the logarithmic conversion factor is K = 2,6 dB for the OATS/SAC to RC
conversion in the frequency range 80 MHz to 1 000 MHz, and K = 7,0 dB for the FSOATS/FAR
to RC conversion in the frequency range 1 GHz to 40 GHz. These conversion factors are useful
for comparison with the values in D.3.
As frequency increases, the directivity increases. Krauthäuser [19] shows and compares differ-
ent expressions; see Figure D.2. For modelling the directivity of unintentional radiators,
Krauthäuser [19] applies two different simulations: 1) the spherical wave expansion, and 2) the
Monte-Carlo method of isotropic point sources. Reference [19] establishes a link between the
two methods − the two models are statistically equivalent for certain values of ka. A relationship
for the number of sources as a function of ka necessary to achieve equivalent distribution func-
tions is given. The number of angle steps to calculate the directivities of large EUTs is also
described.

NOTE The two lines for “Huygen’s Source” and “Short Dipole” are defined for ka = 0,1π only, and therefore are only
visible in the lower left corner.
Figure D.2 ‒ Comparison of different expressions for maximum directivity
of antennas and unintentional emitters as a function of electrical
size ka. µ is the polarization mismatch factor
D.3 Results of modelling
Krauthäuser [19] provides conversion factors as a function of frequency and EUT size from
OATS/SAC to RC, as shown in Figure D.3.
Conversion factors k(f) of Table D.2, Table D.3 and Table D.4 are taken from the ‘mean’ curves.
To convert field-strength limits to limits of the transmitted power, values in dB are more practical
[K(f) = 10lgk(f)]. Consequently, P = E – K(f) [see Equation (15) in 6.10, and Equation (35)
limit limit
and Equation (38) in 8.1]. If conversion factors for other EUT radii are to be determined, inter-
polation should be done between the mean-value curves of Figure D.3.

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CISPR TR 16-4-5:2006/AMD2:2021 – 13 –
 IEC 2021
Table D.5 shows an example of limits for E and P for a = 0,75 m for the residential environment.
The values for the standard deviations σ in the tables are obtained by dividing the difference
between the mean and the quantile values of K(f) by 1,645, assuming a normal distribution (the
factor applies for 5 %, 95 %); e.g. σ = (K(230) − K(230) )/1,645 = 1,34 dB for a = 0,75 m
95 % mean
at 230 MHz. The variable σ is the standard uncertainty of the conversion factor. In the diagrams
of [19], σ increases when k(f) approaches 0.

NOTE Data for a = 0,1 m, 0,75 m and 2,5 m directivities (instead of 100 as in [19]) were provided by Dr. Magdowski
using Krauthäuser’s material.
Figure D.3 – Conversion factors (mean and quantile values) from OATS/SAC
(measurement distance of 10 m) results to RC results and different radii a
of the surrounding sphere as a function of frequency
Table D.2 – Conversion factors (mean, quantile values,
and standard deviation σ) for a = 0,1 m
f
80 230 1 000
MHz
Quantile k(f) K(f) k(f) K(f) k(f) K(f)
σ σ σ
2 2 2 2 2 2
Ω/m dB(Ω/m ) Ω/m dB(Ω/m ) Ω/m dB(Ω/m )
dB dB dB
95 % 2,81 4,49 2,71 4,31 6,34 2,23 5,78 7,62 1,55
Mean 1,05 0,21 1,82 2,60 3,23 5,09
5 % 0,158 −8,0 4,89 0,532 −2,74 3,29 1,47 1,67 2,07

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– 14 – CISPR TR 16-4-5:2006/AMD2:2021
 IEC 2021
Table D.3 – Conversion factors (mean, quantile values,
and standard deviation σ) for a = 0,75 m
f
80 230 1 000
MHz
Quantile k(f) K(f) k(f) K(f) k(f) K(f)
σ σ σ
2 2 2 2 2 2
Ω/m dB(Ω/m ) Ω/m dB(Ω/m ) Ω/m dB(Ω/m )
dB dB dB
95 % 4,31 6,34 2,1 5,86 7,68 1,34 8,93 9,51 1,03
Mean 1,88 2,74 3,57 5,53 6,12 7,87
5 % 0,62 −2,1 3,03 1,87 2,72 1,67 3,64 5,61 1,34

Table D.4 – Conversion factors (mean, quantile values,
and standard deviation σ) for a = 2,5 m
f
80 230 1 000
MHz
Quantile k(f) K(f) k(f) K(f) k(f) K(f)
σ σ σ
2 2 2 2 2 2
Ω/m dB(Ω/m ) Ω/m dB(Ω/m ) Ω/m dB(Ω/m )
dB dB dB
95 % 5,84 7,66 1,92 8,39 9,23 1,24 11,43 10,58 1,3
mean 2,82 4,50 5,18 7,14 8,22 9,15
5 % 1,10 0,41 2,48 3,0 4,77 1,47 5,00 6,99 0,88

Table D.5 – Example of disturbance limits for a = 0,75 m
(EUT diameter 1,5 m) for the residential environment
f
80 230 230 1 000
MHz
E
limit
30 30 37 37
dB(µV/m)
K(f)
2,74 5,53 5,53 7,87
2
dB(Ω/m )
P
limit
27 24 31 29
dB(pW)
P
limit
−63 −66 −59 −61
dBm

Above 1 GHz, the ETM is measurement at an FSOATS/FAR with d = 3 m. Figure D.4 shows the
results of modelling.
The conversion factors of Table D.6, Table D.7, and Table D.8 for frequencies of 1 GHz, 3 GHz,
and 6 GHz are taken from the mean values in Figure D.4 with a = 0,75 m.
Table D.9 shows an example of limits for E and P for a = 0,75 m for the residential environment.

---------------------- Page: 16 ----------------------
CISPR TR 16-4-5:2006/AMD2:2021 – 15 –
 IEC 2021

NOTE Data for a = 0,75 m and 2,5 m, and 1 000 directivities (instead of 100 as in [19]) were provided by Dr.
Magdowski using Krauthäuser’s material.
Figure D.4 – Conversion factors (mean and quantile values) from FSOATS/FAR
(d = 3 m measurement distance) results to RC results and different radii a
of the surrounding sphere as a function of frequency
Table D.6 – Conversion factors (mean, quantile values,
and standard deviation σ) for a = 0,1 m
f
1 3 6
GHz
Quantile k(f) K(f) k(f) K(f) k(f) K(f)
σ σ σ
2 2 2 2 2 2
Ω/m dB(Ω/m ) Ω/m dB(Ω/m ) Ω/m dB(Ω/m )
dB dB dB
95 % 14,80 11,70 1,59 18,54 12,68 1,43 20,02 13,01 1,28
mean 7,97 9,01 10,70 10,29 12,8 11,07
5 % 3,22 5,08 2,43 5,29 7,23 1,88 6,74 8,29 1,59

Table D.7 – Conversion factors (mean, quantile values,
and standard deviation σ) for a = 0,75 m
f
1 3 6
GHz
Quantile k(f
...