CISPR TR 16-4-1:2009

CISPR/TR 16-4-1
Edition 2.0 2009-02
TECHNICAL
REPORT
INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE
Specification for radio disturbance and immunity measuring apparatus and
methods –
Part 4-1: Uncertainties, statistics and limit modelling – Uncertainties in
standardized EMC tests
CISPR/TR 16-4-1:2009(E)
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CISPR/TR 16-4-1
Edition 2.0 2009-02
TECHNICAL
REPORT
INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE
Specification for radio disturbance and immunity measuring apparatus and
methods –
Part 4-1: Uncertainties, statistics and limit modelling – Uncertainties in
standardized EMC tests
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XE
ICS 33.100.10; 33.100.20 ISBN 978-2-88910-014-9
– 2 – TR CISPR 16-4-1 © IEC:2009(E)
CONTENTS
FOREWORD.7
INTRODUCTION.9
1 Scope.10
2 Normative references .10
3 Terms, definitions, and abbreviations .11
3.1 Terms and definitions .12
3.2 Abbreviations .15
4 Basic considerations on uncertainties in emission measurements.15
4.1 Introductory remarks .15
4.2 Types of uncertainties in emission measurements .17
4.2.1 General .17
4.2.2 Purpose of uncertainty considerations .18
4.2.3 Categories of uncertainty sources.19
4.2.4 Summary of types of uncertainties .22
4.2.5 Influence quantities .22
4.2.6 The measurand and the intrinsic uncertainty.23
4.3 Relation between standards compliance uncertainty and interference
probability .25
4.3.1 General .25
4.3.2 The measurand and the associated limit.25
4.3.3 Process of determination and application of uncertainties.26
4.4 Assessment of uncertainties in a standardised emission measurement .27
4.4.1 The process of uncertainty estimation.27
4.4.2 Step 1: Definition of the purpose of the uncertainty consideration.27
4.4.3 Step 2: Identifying the measurand, its uncertainty sources and
influence quantities.28
4.4.4 Step 3: Evaluate the standard uncertainty of each relevant influence
quantity .29
4.4.5 Step 4: Calculation of the combined and expanded uncertainty .30
4.5 Verification of the uncertainty budget .31
4.5.1 Introductory remarks.31
4.5.2 Test laboratory comparison and the measurement compatibility
requirement .32
4.5.3 Interlaboratory comparison and statistical evaluation.34
4.5.4 Application of a ‘calculable EUT’ .35
4.5.5 Application of a ‘reference EUT’ .35
4.6 Reporting of the uncertainty .35
4.6.1 General .35
4.6.2 Reporting results of uncertainty assessments .36
4.6.3 Uncertainty statements in routine compliance measurement results.36
4.6.4 Reporting of the expanded uncertainty .36
4.7 Application of uncertainties in the compliance criterion.37
4.7.1 Introductory remarks.37
4.7.2 Manufacturers’ compliance criterion for compliance measurements .41
4.7.3 Compliance criteria for mass-produced products (80 %/80 % rule) .41
4.7.4 Compliance criteria for quality assurance tests using a reference EUT.42
4.7.5 Application of uncertainties in re-testing .42

TR CISPR 16-4-1 © IEC:2009(E) – 3 –
5 Basic considerations on uncertainties in immunity testing.44
6 Voltage measurements .44
6.1 Introductory remarks .44
6.2 Voltage measurements (general).44
6.2.1 Introductory remarks.44
6.2.2 Voltage measurements basics .44
6.2.3 The disturbance source and types of voltage .46
6.3 Voltage measurements using a voltage probe .48
6.4 Voltage measurement using a V-terminal artificial mains network.48
6.4.1 Introductory remarks.48
6.4.2 Basic circuit diagram of the voltage measurement .49
6.4.3 Voltage measurement and standards compliance uncertainty .50
6.4.4 Combined uncertainty.51
6.4.5 The compliance criterion.52
6.4.6 Influence quantities .52
7 Absorbing clamp measurements .56
7.1 General .56
7.1.1 Objective .56
7.1.2 Introductory remarks.57
7.2 Uncertainties related to the calibration of the absorbing clamp .57
7.2.1 General .57
7.2.2 The measurand .58
7.2.3 Uncertainty sources.58
7.2.4 Influence quantities .59
7.2.5 Application of the uncertainty budget .63
7.2.6 Typical examples of an uncertainty budget .63
7.2.7 Verification of the uncertainty budget.64
7.3 Uncertainties related to the absorbing clamp measurement method .64
7.3.1 General .64
7.3.2 The measurand .64
7.3.3 Uncertainty sources.65
7.3.4 Influence quantities .66
7.3.5 Application of the uncertainty budget .68
7.3.6 Typical examples of the uncertainty budget .68
7.3.7 Verification of the uncertainty budget.69
8 Radiated emission measurements using a SAC or an OATS in the frequency range
of 30 MHz to 1 000 MHz .71
8.1 General .71
8.1.1 Objective .71
8.1.2 Introductory remarks.71
8.2 Uncertainties related to the SAC/OATS radiated emission measurement
method.72
8.2.1 General .72
8.2.2 The measurand .73
8.2.3 Uncertainty sources.74
8.2.4 Influence quantities .75
8.2.5 Application of the uncertainty estimate .86
8.2.6 Typical examples of the uncertainty estimate.86

– 4 – TR CISPR 16-4-1 © IEC:2009(E)
8.2.7 Verification of the uncertainty estimate .87
9 Conducted immunity measurements .88
10 Radiated immunity measurements .88

Annex A (informative) Compliance uncertainty and interference probability.89
Annex B (informative) Numerical example of the consequences of Faraday’s law .91
Annex C (informative) Possible amendments to CISPR publications with regards to
voltage measurements .93
Annex D (informative) Analysis method of results of an interlaboratory test .96
Annex E (informative) Uncertainty budgets for the clamp calibration methods .97
Annex F (informative) Uncertainty budget for the clamp measurement method .99
Annex G (informative) Uncertainty estimates for the radiated emission measurement
methods .101
Annex H (informative) Results of various round robin tests for SAC/OATS-based
radiated emission measurements .106
Annex I (informative) Additional information about distinctions between the terms
measurement uncertainty and standards compliance uncertainty. 112

Bibliography.114

Figure 1 – Illustration of the relation between the overall uncertainty of a measurand
due to contributions from the measurement instrumentation uncertainty and the
intrinsic uncertainty of the measurand.17
Figure 2 – The process of emission compliance measurements and the associated
(categories of) uncertainty sources (see also Table 2) .20
Figure 3 – Relationship between uncertainty sources, influence quantities and
uncertainty categories.25
Figure 4 – Involvement of the subcommittees CISPR/H and CISPR/A in the
determination of the measurands and application of uncertainties.26
Figure 5 – The uncertainty estimation process .27
Figure 6 – Example of a fishbone diagram indicating the various uncertainty sources
for an absorbing clamp compliance measurement in accordance with CISPR 16-2-2 .29
Figure 7 – Illustration of the minimum requirement (interval compatibility requirement)
for the standards compliance uncertainty.33
Figure 8 – Graphical representation of four cases in the compliance determination
process without consideration of measurement uncertainty during limits setting.38
Figure 9 – Graphical representation of four cases in the compliance determination
process with consideration of measurement uncertainty during limits setting. .39
Figure 10 – Generic relation between overall uncertainty of measurand and some
major categories of uncertainties .39
Figure 11 – Graphical representation MIU compliance criterion for compliance
measurements, per CISPR 16-4-2 .41
Figure 12 – Basic circuit of a voltage measurement .45
Figure 13 – Basic circuit of a loaded disturbance source (N = 2) .46
Figure 14 – Relation between the voltages .47
Figure 15 – Basic circuit of the V-AMN voltage measurement (N = 2).49
Figure 16 – Basic circuit of the V-AN measurement during the reading of the received
voltage U (the numbers refer to Figure 15).50
m
TR CISPR 16-4-1 © IEC:2009(E) – 5 –
Figure 17 – The absolute value of the sensitivity coefficient c as a function of the
phase angle difference ϕ of the impedances Z and Z for several values of the
13 d0
ratio |Z /Z | .51
13 d0
Figure 18 – Variation of the parasitic capacitance, and hence of the CM-impedance,
by changing the position of the reference plane (non-conducting EUT housing) .53
Figure 19 – Influence quantities in between the EUT (disturbance source) and the V-
AMN .55
Figure 20 – Schematic overview of the original clamp calibration method .58
Figure 21 – Diagram that illustrates the uncertainty sources associated with the
original clamp calibration method.59
Figure 22 – Schematic overview of the clamp measurement method.64
Figure 23 – Diagram that illustrates the uncertainty sources associated with the clamp
measurement method .65
Figure 24 – Measurement results of an absorbing clamp RRT performed by six test
laboratories in the Netherlands using a drill as EUT.70
Figure 25 – Schematic of a radiated emission measurement set-up in a SAC .72
Figure 26 – Uncertainty sources associated with the SAC/OATS radiated emission
measurement method .74
Figure A.1 – Measured field strength distributions X1 and Y1, emission limit and level
to be protected of relevance in the determination of the corresponding interference
probability determined by distributions X2 and Y2.90
Figure B.1 – Voltage and current limits as given in CISPR 15:2005, Tables 2b and 3,
and the ratio U /I .92
L L
Figure B.2 – Factor K derived from the data in Figure B.1 and Equation (B.4) .92
s
Figure C.1 – Schematic diagram of a V-AMN yielding an improved figure-of-merit about
the actual compliance probability via two current probes.95
Figure H.1 – Expanded uncertainties of emission measurement results for five different
emulated EUTs each with five different cable termination conditions [24]. 108
Figure H.2 – Interlaboratory comparison measurement results of twelve 10 m SACs
[see “HP (2000)” in Table H.1] .108
Figure H.3 – ILC measurement results radiated emission SAC/OATS 3 m (11 sites)
[3 2] 109
Figure H.4 – ILC measurement results radiated emission SAC/OATS 3 m (14 sites)
[ 1 3 ], [2 5] .110
Figure H.5 – Measured correlation curve of 3 m and 10 m SAC/OATS-emission
measurement of a battery-fed table-top type of EUT, compared with the free-space
rule-of-thumb ratio [13], [25] .111

Table 1 – Structure of clauses related to the subject of standards compliance
uncertainty.9
Table 2 – Categories of uncertainty sources in standardised emission measurements .20
Table 3 – Example of detailed standard induced uncertainty sources for a radiated
emission measurement .21
Table 4 – Different types of uncertainties used within CISPR at present .22
Table 5 – Examples (not exhaustive) of the translation of ‘uncertainty sources’ into
‘influence quantities’ for an emission measurement on an OATS per CISPR 22 .23
Table 6 – Influence quantities associated with the uncertainty sources given in
Figure 21 for the original clamp calibration method .60
Table 7 – Influence quantities associated with the uncertainty sources given in
Figure 23 for the clamp measurement method .66

– 6 – TR CISPR 16-4-1 © IEC:2009(E)
Table 8 – Measurement results of an absorbing clamp RRT performed by six test
laboratories in Germany using a vacuum cleaner motor as EUT.70
Table 9 – Summary of various MIU and SCU values (expanded uncertainties) for the
clamp measurement method derived from different sources of information.71
Table 10 – Influence quantities for the SAC/OATS radiated emission measurement
method associated with the uncertainty sources of Figure 26.76
Table 11 – Relation between/and type of EUT and set-up-related uncertainties .77
Table 12 – Example of uncertainty estimate associated with the NSA measurement
method, 30 MHz to 1 000 MHz.82
Table 13 – Relationship between intrinsic and apparent NSA.83
Table E.1 – Uncertainty budget for the original absorbing clamp calibration method in
the frequency range 30 MHz to 300 MHz .97
Table E.2 – Uncertainty budget for the original absorbing clamp calibration method in
the frequency range 300 MHz to 1 000 MHz .98
Table F.1 – Uncertainty budget for the absorbing clamp measurement method in the
frequency range 30 MHz to 300 MHz .99
Table F.2 – Uncertainty budget for the absorbing clamp measurement method in the
frequency range 300 MHz to 1 000 MHz .100
Table G.1 – Uncertainty estimate for the radiated emission measurement method in the
frequency range 30 MHz to 200 MHz at a measurement distance of 3 m. 102
Table G.2 – Uncertainty estimate for the radiated emission measurement method in the
frequency range 200 MHz to 1 000 MHz at a measurement distance of 3 m. 103
Table G.3 – Uncertainty data of some influence quantities for the radiated emission
measurement method in the frequency range 30 MHz to 200 MHz at measurement
distances of 3 m, 10 m, or 30 m .104
Table G.4 – Uncertainty data of some influence quantities for the radiated emission
measurement method in the frequency range 200 MHz to 1 000 MHz at measurement
distances of 3 m, 10 m, or 30 m .105
Table H.1 – Summary of various MIU and SCU uncertainty values for the SAC/OATS-
based radiated emission measurement method, assembled from various sources.107

TR CISPR 16-4-1 © IEC:2009(E) – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SPECIFICATION FOR RADIO DISTURBANCE AND IMMUNITY
MEASURING APPARATUS AND METHODS –

Part 4-1: Uncertainties, statistics and limit modelling –
Uncertainties in standardized EMC tests

FOREWORD
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5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
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6) All users should ensure that they have the latest edition of this publication.
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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) 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.
The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
CISPR 16-4-1, which is a technical report, has been prepared by CISPR subcommittee A:
Radio-interference measurements and statistical methods, of IEC technical committee CISPR:
International special committee on radio interference.
This second edition of CISPR 16-4-1 cancels and replaces the first edition published in 2003,
and its Amendments 1 (2004) and 2 (2007). It constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition. The provisions available for application of uncertainties in the determination of the

– 8 – TR CISPR 16-4-1 © IEC:2009(E)
compliance criterion are explained more generally and a procedure is added for re-testing an
approved EUT by another test house.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
CISPR/A/818/DTR CISPR/A/831/RVC

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.
A list of all parts of the CISPR 16 series can be found, under the general title Specification for
radio disturbance and immunity measuring apparatus and methods, on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

TR CISPR 16-4-1 © IEC:2009(E) – 9 –
INTRODUCTION
The result of the application of basic considerations (Clauses 4 a nd 5) in this part to existing
or new CISPR standards will lead to proposals to improve and harmonise the uncertainty
aspects of those CISPR standards. Such proposals will also be published as reports within
this part and will give the background and rationale for improvement of certain
CISPR standards. Clause 6 is an example of such a report.
The structure of clauses related to the CISPR standards compliance uncertainty work is
depicted in Table 1. Clause 4 deals with the basic considerations of standards compliance
uncertainties in emission measurements. Clauses 6, 7 an d 8 contain uncertainty
considerations related to voltage, absorbing clamp and radiated emission measurements,
respectively.
Uncertainty work will also be considered for immunity compliance tests in the future. Clauses
5, 9 an d 10 are reserved for this material. SCU (see 3.1.16) considerations of immunity tests
differ from the emission SCU considerations in particular points. For instance, in an immunity
test, the measurand is often a functional attribute of the EUT and not a specific quantity. This
may cause additional specific SCU considerations. Priority has been given to the uncertainty
evaluations for emission measurements at this stage of the work.
Table 1 – Structure of clauses related to the subject
of standards compliance uncertainty
STANDARDS COMPLIANCE UNCERTAINTY
Clause 1, 2, an d 3: Gene ral
EMISSION IMMUNITY
Clause 4 B as i c c ons i der at i ons Cl aus e 5 B as i c c ons i der at i ons
Clause 6 V ol t age m eas u r em ent s Cl aus e 9 Conducted immunity tests
Clause 7 Absorbing clamp measurements Clause 10 Radiated immunity tests
Clause 8 Radiated emission measurements

– 10 – TR CISPR 16-4-1 © IEC:2009(E)
SPECIFICATION FOR RADIO DISTURBANCE AND IMMUNITY
MEASURING APPARATUS AND METHODS –

Part 4-1: Uncertainties, statistics and limit modelling –
Uncertainties in standardized EMC tests

1 Scope
This part of CISPR 16-4 gives guidance on the treatment of uncertainties to those who are
involved in the development or modification of CISPR electromagnetic compatibility (EMC)
standards. In addition, this part provides useful background information for those who apply
the standards and the uncertainty aspects in practice.
The objectives of this part are to:
a) identify the parameters or sources governing the uncertainty associated with the
statement that a given product complies with the requirement specified in a
CISPR recommendation. This uncertainty will be called “standards compliance
uncertainty” (SCU, see 3.1.16);
b) give guidance on the estimation of the magnitude of the standards compliance
uncertainty;
c) give guidance for the implementation of the standards compliance uncertainty into the
compliance criterion of a CISPR standardised compliance test.
As such, this part can be considered as a handbook that can be used by standards writers to
incorporate and harmonise uncertainty considerations in existing and future CISPR standards.
This part also gives guidance to regulatory authorities, accreditation bodies and test
engineers to judge the performance quality of an EMC test-laboratory carrying out
CISPR standardised compliance tests. The uncertainty considerations given in this part can
also be used as guidance when comparing test results (and their uncertainties) obtained by
using different alternative test methods.
The uncertainty of a compliance test also relates to the probability of occurrence of an
electromagnetic interference (EMI) problem in practice. This aspect is recognized and
introduced briefly in this part. However, the problem of relating uncertainties of a compliance
test to the occurrence of EMI in practice is not considered within the scope of this part.
The scope of this part is limited to all the relevant uncertainty considerations of a
standardized EMC compliance test.
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 60050-161:1990, International Electrotechnical Vocabulary (IEV) – Chapter 161:
Electromagnetic Compatibility
IEC 60050-300:2001, International Electrotechnical Vocabulary (IEV) – Electrical and
electronic measurements and measuring instruments – Part 311: General terms relating to
measurements – Part 312: General terms relating to electrical measurements – Part 313:
Types of electrical measuring instruments – Part 314: Specific terms according to the type of
instrument
TR CISPR 16-4-1 © IEC:2009(E) – 11 –
IEC 60359:2001, Electrical and electronic measurement equipment – Expression of
performance
CISPR 16-1-2:2003, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 1-2: Radio disturbance and immunity measuring apparatus – Conducted
disturbances
CISPR 16-1-3:2004, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 1-3: Radio disturbance and immunity measuring apparatus – Ancillary
equipment – Disturbance power
CISPR 16-1-4:2007, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 1-4: Radio disturbance and immunity measuring apparatus – Ancillary
equipment – Radiated disturbances
CISPR 16-1-5:2003, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 1-5: Radio disturbance and immunity measuring apparatus – Antenna
calibration test sites for 30 MHz to 1 000 MHz
CISPR 16-2-2:2003, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 2-2: Methods of measurement of disturbances and immunity –
Measurement of disturbance power
Amendment 1 (2004)
Amendment 2 (2005)
CISPR 16-2-3:2006, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 2-3: Methods of measurement of disturbances and immunity – Radiated
disturbance measurements
CISPR 16-4-2:2003, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 4-2: Uncertainties, statistics and limit modelling – Uncertainty in EMC
measurements
CISPR/TR 16-4-3:2004, Specification for radio disturbance and immunity measuring
apparatus and methods – Part 4-3: Uncertainties, statistics and limit modelling – Statistical
considerations in the determination of EMC compliance of mass-produced products
CISPR 22:2008, Information technology equipment – Radio disturbance characteristics –
Limits and methods of measurement
ISO/IEC 17025, General requirements for the competence of testing and calibration
laboratories
ISO/IEC Guide 98-3:2008, Uncertainty of measurement – Part 3: Guide to the expression of
uncertainty in measurement (GUM:1995)
ISO/IEC Guide 99:2007, International vocabulary of metrology – Basic and general concepts
and associated terms (VIM)
3 Terms, definitions, and abbreviations
For the purposes of this document, the following terms, definitions and abbreviations apply.
NOTE 1 Wherever possible, existing terminology, from the normative standards of Clause 2 is used. Additional
terms and definitions not included in those standards are listed below.
NOTE 2 Terms shown in bold are defined in this clause.

– 12 – TR CISPR 16-4-1 © IEC:2009(E)
3.1 Terms and definitions
3.1.1
electromagnetic (EM) disturbance
any electromagnetic phenomenon which may degrade the performance of a device,
equipment or system, or adversely affect living or inert matter
[IEV 161-01-05]
3.1.2
emission level
the level of a given electromagnetic disturbance emitted from a particular device, equipment
or system measured in a specified way
[IEV 161-03-11, modified]
3.1.3
emission limit
the specified maximum emission level of a source of electromagnetic disturbance
NOTE In IEC this limit has been defined as “the maximum permissible emission level”.
[IEV 161-03-12, modified]
3.1.4
influence quantity
quantity that is not the measurand but that affects the result of the measurement
[ISO/IEC Guide 98-3, B.2.10]
NOTE 1 In a standardised compliance test an influence quantity may be specified or non-specified. Specified
influence quantities preferably include tolerance data.
NOTE 2 An example of a specified influence quantity is the measurement impedance of an artificial mains
network. An example of a non-specified influence quantity is the internal impedance of an EM disturbance source.
3.1.5
interference probability
probability that a product complying with the EMC requirements will function satisfactorily
(from an EMC point of view) in its normal use in an electromagnetic environment
3.1.6
intrinsic uncertainty of the measurand
minimum uncertainty that can be assigned in the description of a measured quantity. In
theory, the intrinsic uncertainty of the measurand is obtained if the measurand is measured
using a measurement system having a negligible measurement instrumentation uncertainty
NOTE 1 No quantity can be measured with continually lower uncertainty, inasmuch as any given quantity is
defined or identified at a given level of detail. If one tries to measure a given quantity at an uncertainty lower than
its own intrinsic uncertainty one is compelled to redefine it with higher detail, so that one is actually measuring
another quantity. See also ISO/IEC Guide 98-3, D.1.1.
NOTE 2 The result of a measurement carried out with the intrinsic uncertainty of the measurand may be called the
best measurement of the quantity in question.
[IEC 60359:2001, definition 3.1.11, modified]
3.1.7
intrinsic uncertainty of the measurement instrumentation
uncertainty of a measurement instrumentation when used under reference conditions. In
theory, the intrinsic uncertainty of the measurement instrumentation is obtained if the
intrinsic uncertainty of the measurand is negligible

TR CISPR 16-4-1 © IEC:2009(E) – 13 –
NOTE Application of a reference EUT is a means to create reference conditions in order to obtain the intrinsic
uncertainty of the measurement instrumentation ( 4. 5. 5 ) .
[IEC 60359:2001, definition 3.2.10, modified]
3.1.8
level
value of a quantity, such as a power or a field quantity, measured and/or evaluated in a
specified manner during a specified time interval
NOTE The level may be expressed in logarithmic units, for example in decibels with respect to a reference value.
[IEV 161-03-01, modified]
3.1.9
measurand
particular quantity subject to measurement
[IEV 311-01-03]
EXAMPLE Electric field, measured at a distance of 3 m, of a given sample.
NOTE The specification of a measurand may require statements about influence quantities (see ISO/IEC Guide
98-3, B.2.9).
3.1.10
measurement instrumentation uncertainty
MIU
parameter, associated with the result of a measurement that characterises the dispersion of
the values that can reasonably be attributed to the measurand, induced by all relevant
influence quantities that are related to the measurement instrumentation
[ISO/IEC Guide 99, 4.24, and IEC 60359:2001, 3.1.4, modified]
3.1.11
measuring chain
series of elements of a measuring instrument or system that constitutes the path of the
measuring signal from input to the output
[IEV 311-03-07, modified]
3.1.12
(measurement) compatibility
property satisfied by all the results of measurement of the same measurand, characterized by
an adequate overlap of their intervals
[IEV 311-01-14]
3.1.13
reference conditions
set of specified values and/or ranges of values of influence quantities under which the
uncertainties, or limits of error, admissible for the measurement system are smallest
[IEV 311-06-02, modified]
3.1.14
reproducibility (of results of measurements)
closeness of the agreement between the results of successive measurements of the same
measurand carried out under changed conditions as determined by one or more specified
influence quantities
– 14 – TR CISPR 16-4-1 © IEC:2009(E)
NOTE In general, this reproducibility is also determined by non-specified influence quantities, hence the
closeness of the agreement can only be stated in terms of probability.
[ISO/IEC Guide 98-3, B.2.16, modified]
3.1.15
sensitivity coefficient
coefficient used to relate the change of a physical quantity due to a variation of one of the
specified or non-specified influence quantities
NOTE 1 In mathematical form, the sensitivity coefficient is, in general, the partial derivative of the physical
quantity wit
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